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-rw-r--r--Documentation/laptops/00-INDEX18
-rw-r--r--Documentation/laptops/Makefile8
-rw-r--r--Documentation/laptops/asus-laptop.txt257
-rw-r--r--Documentation/laptops/disk-shock-protection.txt149
-rw-r--r--Documentation/laptops/dslm.c166
-rw-r--r--Documentation/laptops/hpfall.c146
-rw-r--r--Documentation/laptops/laptop-mode.txt782
-rw-r--r--Documentation/laptops/sony-laptop.txt144
-rw-r--r--Documentation/laptops/sonypi.txt152
-rw-r--r--Documentation/laptops/thinkpad-acpi.txt1519
10 files changed, 3341 insertions, 0 deletions
diff --git a/Documentation/laptops/00-INDEX b/Documentation/laptops/00-INDEX
new file mode 100644
index 00000000..fa688538
--- /dev/null
+++ b/Documentation/laptops/00-INDEX
@@ -0,0 +1,18 @@
+00-INDEX
+ - This file
+acer-wmi.txt
+ - information on the Acer Laptop WMI Extras driver.
+asus-laptop.txt
+ - information on the Asus Laptop Extras driver.
+disk-shock-protection.txt
+ - information on hard disk shock protection.
+dslm.c
+ - Simple Disk Sleep Monitor program
+laptop-mode.txt
+ - how to conserve battery power using laptop-mode.
+sony-laptop.txt
+ - Sony Notebook Control Driver (SNC) Readme.
+sonypi.txt
+ - info on Linux Sony Programmable I/O Device support.
+thinkpad-acpi.txt
+ - information on the (IBM and Lenovo) ThinkPad ACPI Extras driver.
diff --git a/Documentation/laptops/Makefile b/Documentation/laptops/Makefile
new file mode 100644
index 00000000..5cb144af
--- /dev/null
+++ b/Documentation/laptops/Makefile
@@ -0,0 +1,8 @@
+# kbuild trick to avoid linker error. Can be omitted if a module is built.
+obj- := dummy.o
+
+# List of programs to build
+hostprogs-y := dslm
+
+# Tell kbuild to always build the programs
+always := $(hostprogs-y)
diff --git a/Documentation/laptops/asus-laptop.txt b/Documentation/laptops/asus-laptop.txt
new file mode 100644
index 00000000..69f9fb37
--- /dev/null
+++ b/Documentation/laptops/asus-laptop.txt
@@ -0,0 +1,257 @@
+Asus Laptop Extras
+
+Version 0.1
+August 6, 2009
+
+Corentin Chary <corentincj@iksaif.net>
+http://acpi4asus.sf.net/
+
+ This driver provides support for extra features of ACPI-compatible ASUS laptops.
+ It may also support some MEDION, JVC or VICTOR laptops (such as MEDION 9675 or
+ VICTOR XP7210 for example). It makes all the extra buttons generate standard
+ ACPI events that go through /proc/acpi/events and input events (like keyboards).
+ On some models adds support for changing the display brightness and output,
+ switching the LCD backlight on and off, and most importantly, allows you to
+ blink those fancy LEDs intended for reporting mail and wireless status.
+
+This driver supercedes the old asus_acpi driver.
+
+Requirements
+------------
+
+ Kernel 2.6.X sources, configured for your computer, with ACPI support.
+ You also need CONFIG_INPUT and CONFIG_ACPI.
+
+Status
+------
+
+ The features currently supported are the following (see below for
+ detailed description):
+
+ - Fn key combinations
+ - Bluetooth enable and disable
+ - Wlan enable and disable
+ - GPS enable and disable
+ - Video output switching
+ - Ambient Light Sensor on and off
+ - LED control
+ - LED Display control
+ - LCD brightness control
+ - LCD on and off
+
+ A compatibility table by model and feature is maintained on the web
+ site, http://acpi4asus.sf.net/.
+
+Usage
+-----
+
+ Try "modprobe asus-laptop". Check your dmesg (simply type dmesg). You should
+ see some lines like this :
+
+ Asus Laptop Extras version 0.42
+ L2D model detected.
+
+ If it is not the output you have on your laptop, send it (and the laptop's
+ DSDT) to me.
+
+ That's all, now, all the events generated by the hotkeys of your laptop
+ should be reported in your /proc/acpi/event entry. You can check with
+ "acpi_listen".
+
+ Hotkeys are also reported as input keys (like keyboards) you can check
+ which key are supported using "xev" under X11.
+
+ You can get information on the version of your DSDT table by reading the
+ /sys/devices/platform/asus-laptop/infos entry. If you have a question or a
+ bug report to do, please include the output of this entry.
+
+LEDs
+----
+
+ You can modify LEDs be echoing values to /sys/class/leds/asus::*/brightness :
+ echo 1 > /sys/class/leds/asus::mail/brightness
+ will switch the mail LED on.
+ You can also know if they are on/off by reading their content and use
+ kernel triggers like ide-disk or heartbeat.
+
+Backlight
+---------
+
+ You can control lcd backlight power and brightness with
+ /sys/class/backlight/asus-laptop/. Brightness Values are between 0 and 15.
+
+Wireless devices
+---------------
+
+ You can turn the internal Bluetooth adapter on/off with the bluetooth entry
+ (only on models with Bluetooth). This usually controls the associated LED.
+ Same for Wlan adapter.
+
+Display switching
+-----------------
+
+ Note: the display switching code is currently considered EXPERIMENTAL.
+
+ Switching works for the following models:
+ L3800C
+ A2500H
+ L5800C
+ M5200N
+ W1000N (albeit with some glitches)
+ M6700R
+ A6JC
+ F3J
+
+ Switching doesn't work for the following:
+ M3700N
+ L2X00D (locks the laptop under certain conditions)
+
+ To switch the displays, echo values from 0 to 15 to
+ /sys/devices/platform/asus-laptop/display. The significance of those values
+ is as follows:
+
+ +-------+-----+-----+-----+-----+-----+
+ | Bin | Val | DVI | TV | CRT | LCD |
+ +-------+-----+-----+-----+-----+-----+
+ + 0000 + 0 + + + + +
+ +-------+-----+-----+-----+-----+-----+
+ + 0001 + 1 + + + + X +
+ +-------+-----+-----+-----+-----+-----+
+ + 0010 + 2 + + + X + +
+ +-------+-----+-----+-----+-----+-----+
+ + 0011 + 3 + + + X + X +
+ +-------+-----+-----+-----+-----+-----+
+ + 0100 + 4 + + X + + +
+ +-------+-----+-----+-----+-----+-----+
+ + 0101 + 5 + + X + + X +
+ +-------+-----+-----+-----+-----+-----+
+ + 0110 + 6 + + X + X + +
+ +-------+-----+-----+-----+-----+-----+
+ + 0111 + 7 + + X + X + X +
+ +-------+-----+-----+-----+-----+-----+
+ + 1000 + 8 + X + + + +
+ +-------+-----+-----+-----+-----+-----+
+ + 1001 + 9 + X + + + X +
+ +-------+-----+-----+-----+-----+-----+
+ + 1010 + 10 + X + + X + +
+ +-------+-----+-----+-----+-----+-----+
+ + 1011 + 11 + X + + X + X +
+ +-------+-----+-----+-----+-----+-----+
+ + 1100 + 12 + X + X + + +
+ +-------+-----+-----+-----+-----+-----+
+ + 1101 + 13 + X + X + + X +
+ +-------+-----+-----+-----+-----+-----+
+ + 1110 + 14 + X + X + X + +
+ +-------+-----+-----+-----+-----+-----+
+ + 1111 + 15 + X + X + X + X +
+ +-------+-----+-----+-----+-----+-----+
+
+ In most cases, the appropriate displays must be plugged in for the above
+ combinations to work. TV-Out may need to be initialized at boot time.
+
+ Debugging:
+ 1) Check whether the Fn+F8 key:
+ a) does not lock the laptop (try a boot with noapic / nolapic if it does)
+ b) generates events (0x6n, where n is the value corresponding to the
+ configuration above)
+ c) actually works
+ Record the disp value at every configuration.
+ 2) Echo values from 0 to 15 to /sys/devices/platform/asus-laptop/display.
+ Record its value, note any change. If nothing changes, try a broader range,
+ up to 65535.
+ 3) Send ANY output (both positive and negative reports are needed, unless your
+ machine is already listed above) to the acpi4asus-user mailing list.
+
+ Note: on some machines (e.g. L3C), after the module has been loaded, only 0x6n
+ events are generated and no actual switching occurs. In such a case, a line
+ like:
+
+ echo $((10#$arg-60)) > /sys/devices/platform/asus-laptop/display
+
+ will usually do the trick ($arg is the 0000006n-like event passed to acpid).
+
+ Note: there is currently no reliable way to read display status on xxN
+ (Centrino) models.
+
+LED display
+-----------
+
+ Some models like the W1N have a LED display that can be used to display
+ several items of information.
+
+ LED display works for the following models:
+ W1000N
+ W1J
+
+ To control the LED display, use the following :
+
+ echo 0x0T000DDD > /sys/devices/platform/asus-laptop/
+
+ where T control the 3 letters display, and DDD the 3 digits display,
+ according to the tables below.
+
+ DDD (digits)
+ 000 to 999 = display digits
+ AAA = ---
+ BBB to FFF = turn-off
+
+ T (type)
+ 0 = off
+ 1 = dvd
+ 2 = vcd
+ 3 = mp3
+ 4 = cd
+ 5 = tv
+ 6 = cpu
+ 7 = vol
+
+ For example "echo 0x01000001 >/sys/devices/platform/asus-laptop/ledd"
+ would display "DVD001".
+
+Driver options:
+---------------
+
+ Options can be passed to the asus-laptop driver using the standard
+ module argument syntax (<param>=<value> when passing the option to the
+ module or asus-laptop.<param>=<value> on the kernel boot line when
+ asus-laptop is statically linked into the kernel).
+
+ wapf: WAPF defines the behavior of the Fn+Fx wlan key
+ The significance of values is yet to be found, but
+ most of the time:
+ - 0x0 should do nothing
+ - 0x1 should allow to control the device with Fn+Fx key.
+ - 0x4 should send an ACPI event (0x88) while pressing the Fn+Fx key
+ - 0x5 like 0x1 or 0x4
+
+ The default value is 0x1.
+
+Unsupported models
+------------------
+
+ These models will never be supported by this module, as they use a completely
+ different mechanism to handle LEDs and extra stuff (meaning we have no clue
+ how it works):
+
+ - ASUS A1300 (A1B), A1370D
+ - ASUS L7300G
+ - ASUS L8400
+
+Patches, Errors, Questions:
+--------------------------
+
+ I appreciate any success or failure
+ reports, especially if they add to or correct the compatibility table.
+ Please include the following information in your report:
+
+ - Asus model name
+ - a copy of your ACPI tables, using the "acpidump" utility
+ - a copy of /sys/devices/platform/asus-laptop/infos
+ - which driver features work and which don't
+ - the observed behavior of non-working features
+
+ Any other comments or patches are also more than welcome.
+
+ acpi4asus-user@lists.sourceforge.net
+ http://sourceforge.net/projects/acpi4asus
+
diff --git a/Documentation/laptops/disk-shock-protection.txt b/Documentation/laptops/disk-shock-protection.txt
new file mode 100644
index 00000000..0e6ba266
--- /dev/null
+++ b/Documentation/laptops/disk-shock-protection.txt
@@ -0,0 +1,149 @@
+Hard disk shock protection
+==========================
+
+Author: Elias Oltmanns <eo@nebensachen.de>
+Last modified: 2008-10-03
+
+
+0. Contents
+-----------
+
+1. Intro
+2. The interface
+3. References
+4. CREDITS
+
+
+1. Intro
+--------
+
+ATA/ATAPI-7 specifies the IDLE IMMEDIATE command with unload feature.
+Issuing this command should cause the drive to switch to idle mode and
+unload disk heads. This feature is being used in modern laptops in
+conjunction with accelerometers and appropriate software to implement
+a shock protection facility. The idea is to stop all I/O operations on
+the internal hard drive and park its heads on the ramp when critical
+situations are anticipated. The desire to have such a feature
+available on GNU/Linux systems has been the original motivation to
+implement a generic disk head parking interface in the Linux kernel.
+Please note, however, that other components have to be set up on your
+system in order to get disk shock protection working (see
+section 3. References below for pointers to more information about
+that).
+
+
+2. The interface
+----------------
+
+For each ATA device, the kernel exports the file
+block/*/device/unload_heads in sysfs (here assumed to be mounted under
+/sys). Access to /sys/block/*/device/unload_heads is denied with
+-EOPNOTSUPP if the device does not support the unload feature.
+Otherwise, writing an integer value to this file will take the heads
+of the respective drive off the platter and block all I/O operations
+for the specified number of milliseconds. When the timeout expires and
+no further disk head park request has been issued in the meantime,
+normal operation will be resumed. The maximal value accepted for a
+timeout is 30000 milliseconds. Exceeding this limit will return
+-EOVERFLOW, but heads will be parked anyway and the timeout will be
+set to 30 seconds. However, you can always change a timeout to any
+value between 0 and 30000 by issuing a subsequent head park request
+before the timeout of the previous one has expired. In particular, the
+total timeout can exceed 30 seconds and, more importantly, you can
+cancel a previously set timeout and resume normal operation
+immediately by specifying a timeout of 0. Values below -2 are rejected
+with -EINVAL (see below for the special meaning of -1 and -2). If the
+timeout specified for a recent head park request has not yet expired,
+reading from /sys/block/*/device/unload_heads will report the number
+of milliseconds remaining until normal operation will be resumed;
+otherwise, reading the unload_heads attribute will return 0.
+
+For example, do the following in order to park the heads of drive
+/dev/sda and stop all I/O operations for five seconds:
+
+# echo 5000 > /sys/block/sda/device/unload_heads
+
+A simple
+
+# cat /sys/block/sda/device/unload_heads
+
+will show you how many milliseconds are left before normal operation
+will be resumed.
+
+A word of caution: The fact that the interface operates on a basis of
+milliseconds may raise expectations that cannot be satisfied in
+reality. In fact, the ATA specs clearly state that the time for an
+unload operation to complete is vendor specific. The hint in ATA-7
+that this will typically be within 500 milliseconds apparently has
+been dropped in ATA-8.
+
+There is a technical detail of this implementation that may cause some
+confusion and should be discussed here. When a head park request has
+been issued to a device successfully, all I/O operations on the
+controller port this device is attached to will be deferred. That is
+to say, any other device that may be connected to the same port will
+be affected too. The only exception is that a subsequent head unload
+request to that other device will be executed immediately. Further
+operations on that port will be deferred until the timeout specified
+for either device on the port has expired. As far as PATA (old style
+IDE) configurations are concerned, there can only be two devices
+attached to any single port. In SATA world we have port multipliers
+which means that a user-issued head parking request to one device may
+actually result in stopping I/O to a whole bunch of devices. However,
+since this feature is supposed to be used on laptops and does not seem
+to be very useful in any other environment, there will be mostly one
+device per port. Even if the CD/DVD writer happens to be connected to
+the same port as the hard drive, it generally *should* recover just
+fine from the occasional buffer under-run incurred by a head park
+request to the HD. Actually, when you are using an ide driver rather
+than its libata counterpart (i.e. your disk is called /dev/hda
+instead of /dev/sda), then parking the heads of one drive (drive X)
+will generally not affect the mode of operation of another drive
+(drive Y) on the same port as described above. It is only when a port
+reset is required to recover from an exception on drive Y that further
+I/O operations on that drive (and the reset itself) will be delayed
+until drive X is no longer in the parked state.
+
+Finally, there are some hard drives that only comply with an earlier
+version of the ATA standard than ATA-7, but do support the unload
+feature nonetheless. Unfortunately, there is no safe way Linux can
+detect these devices, so you won't be able to write to the
+unload_heads attribute. If you know that your device really does
+support the unload feature (for instance, because the vendor of your
+laptop or the hard drive itself told you so), then you can tell the
+kernel to enable the usage of this feature for that drive by writing
+the special value -1 to the unload_heads attribute:
+
+# echo -1 > /sys/block/sda/device/unload_heads
+
+will enable the feature for /dev/sda, and giving -2 instead of -1 will
+disable it again.
+
+
+3. References
+-------------
+
+There are several laptops from different vendors featuring shock
+protection capabilities. As manufacturers have refused to support open
+source development of the required software components so far, Linux
+support for shock protection varies considerably between different
+hardware implementations. Ideally, this section should contain a list
+of pointers at different projects aiming at an implementation of shock
+protection on different systems. Unfortunately, I only know of a
+single project which, although still considered experimental, is fit
+for use. Please feel free to add projects that have been the victims
+of my ignorance.
+
+- http://www.thinkwiki.org/wiki/HDAPS
+ See this page for information about Linux support of the hard disk
+ active protection system as implemented in IBM/Lenovo Thinkpads.
+
+
+4. CREDITS
+----------
+
+This implementation of disk head parking has been inspired by a patch
+originally published by Jon Escombe <lists@dresco.co.uk>. My efforts
+to develop an implementation of this feature that is fit to be merged
+into mainline have been aided by various kernel developers, in
+particular by Tejun Heo and Bartlomiej Zolnierkiewicz.
diff --git a/Documentation/laptops/dslm.c b/Documentation/laptops/dslm.c
new file mode 100644
index 00000000..72ff290c
--- /dev/null
+++ b/Documentation/laptops/dslm.c
@@ -0,0 +1,166 @@
+/*
+ * dslm.c
+ * Simple Disk Sleep Monitor
+ * by Bartek Kania
+ * Licenced under the GPL
+ */
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <time.h>
+#include <string.h>
+#include <signal.h>
+#include <sys/ioctl.h>
+#include <linux/hdreg.h>
+
+#ifdef DEBUG
+#define D(x) x
+#else
+#define D(x)
+#endif
+
+int endit = 0;
+
+/* Check if the disk is in powersave-mode
+ * Most of the code is stolen from hdparm.
+ * 1 = active, 0 = standby/sleep, -1 = unknown */
+static int check_powermode(int fd)
+{
+ unsigned char args[4] = {WIN_CHECKPOWERMODE1,0,0,0};
+ int state;
+
+ if (ioctl(fd, HDIO_DRIVE_CMD, &args)
+ && (args[0] = WIN_CHECKPOWERMODE2) /* try again with 0x98 */
+ && ioctl(fd, HDIO_DRIVE_CMD, &args)) {
+ if (errno != EIO || args[0] != 0 || args[1] != 0) {
+ state = -1; /* "unknown"; */
+ } else
+ state = 0; /* "sleeping"; */
+ } else {
+ state = (args[2] == 255) ? 1 : 0;
+ }
+ D(printf(" drive state is: %d\n", state));
+
+ return state;
+}
+
+static char *state_name(int i)
+{
+ if (i == -1) return "unknown";
+ if (i == 0) return "sleeping";
+ if (i == 1) return "active";
+
+ return "internal error";
+}
+
+static char *myctime(time_t time)
+{
+ char *ts = ctime(&time);
+ ts[strlen(ts) - 1] = 0;
+
+ return ts;
+}
+
+static void measure(int fd)
+{
+ time_t start_time;
+ int last_state;
+ time_t last_time;
+ int curr_state;
+ time_t curr_time = 0;
+ time_t time_diff;
+ time_t active_time = 0;
+ time_t sleep_time = 0;
+ time_t unknown_time = 0;
+ time_t total_time = 0;
+ int changes = 0;
+ float tmp;
+
+ printf("Starting measurements\n");
+
+ last_state = check_powermode(fd);
+ start_time = last_time = time(0);
+ printf(" System is in state %s\n\n", state_name(last_state));
+
+ while(!endit) {
+ sleep(1);
+ curr_state = check_powermode(fd);
+
+ if (curr_state != last_state || endit) {
+ changes++;
+ curr_time = time(0);
+ time_diff = curr_time - last_time;
+
+ if (last_state == 1) active_time += time_diff;
+ else if (last_state == 0) sleep_time += time_diff;
+ else unknown_time += time_diff;
+
+ last_state = curr_state;
+ last_time = curr_time;
+
+ printf("%s: State-change to %s\n", myctime(curr_time),
+ state_name(curr_state));
+ }
+ }
+ changes--; /* Compensate for SIGINT */
+
+ total_time = time(0) - start_time;
+ printf("\nTotal running time: %lus\n", curr_time - start_time);
+ printf(" State changed %d times\n", changes);
+
+ tmp = (float)sleep_time / (float)total_time * 100;
+ printf(" Time in sleep state: %lus (%.2f%%)\n", sleep_time, tmp);
+ tmp = (float)active_time / (float)total_time * 100;
+ printf(" Time in active state: %lus (%.2f%%)\n", active_time, tmp);
+ tmp = (float)unknown_time / (float)total_time * 100;
+ printf(" Time in unknown state: %lus (%.2f%%)\n", unknown_time, tmp);
+}
+
+static void ender(int s)
+{
+ endit = 1;
+}
+
+static void usage(void)
+{
+ puts("usage: dslm [-w <time>] <disk>");
+ exit(0);
+}
+
+int main(int argc, char **argv)
+{
+ int fd;
+ char *disk = 0;
+ int settle_time = 60;
+
+ /* Parse the simple command-line */
+ if (argc == 2)
+ disk = argv[1];
+ else if (argc == 4) {
+ settle_time = atoi(argv[2]);
+ disk = argv[3];
+ } else
+ usage();
+
+ if (!(fd = open(disk, O_RDONLY|O_NONBLOCK))) {
+ printf("Can't open %s, because: %s\n", disk, strerror(errno));
+ exit(-1);
+ }
+
+ if (settle_time) {
+ printf("Waiting %d seconds for the system to settle down to "
+ "'normal'\n", settle_time);
+ sleep(settle_time);
+ } else
+ puts("Not waiting for system to settle down");
+
+ signal(SIGINT, ender);
+
+ measure(fd);
+
+ close(fd);
+
+ return 0;
+}
diff --git a/Documentation/laptops/hpfall.c b/Documentation/laptops/hpfall.c
new file mode 100644
index 00000000..a4a8fc5d
--- /dev/null
+++ b/Documentation/laptops/hpfall.c
@@ -0,0 +1,146 @@
+/* Disk protection for HP machines.
+ *
+ * Copyright 2008 Eric Piel
+ * Copyright 2009 Pavel Machek <pavel@ucw.cz>
+ *
+ * GPLv2.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <string.h>
+#include <stdint.h>
+#include <errno.h>
+#include <signal.h>
+#include <sys/mman.h>
+#include <sched.h>
+
+char unload_heads_path[64];
+
+int set_unload_heads_path(char *device)
+{
+ char devname[64];
+
+ if (strlen(device) <= 5 || strncmp(device, "/dev/", 5) != 0)
+ return -EINVAL;
+ strncpy(devname, device + 5, sizeof(devname));
+
+ snprintf(unload_heads_path, sizeof(unload_heads_path),
+ "/sys/block/%s/device/unload_heads", devname);
+ return 0;
+}
+int valid_disk(void)
+{
+ int fd = open(unload_heads_path, O_RDONLY);
+ if (fd < 0) {
+ perror(unload_heads_path);
+ return 0;
+ }
+
+ close(fd);
+ return 1;
+}
+
+void write_int(char *path, int i)
+{
+ char buf[1024];
+ int fd = open(path, O_RDWR);
+ if (fd < 0) {
+ perror("open");
+ exit(1);
+ }
+ sprintf(buf, "%d", i);
+ if (write(fd, buf, strlen(buf)) != strlen(buf)) {
+ perror("write");
+ exit(1);
+ }
+ close(fd);
+}
+
+void set_led(int on)
+{
+ write_int("/sys/class/leds/hp::hddprotect/brightness", on);
+}
+
+void protect(int seconds)
+{
+ write_int(unload_heads_path, seconds*1000);
+}
+
+int on_ac(void)
+{
+// /sys/class/power_supply/AC0/online
+}
+
+int lid_open(void)
+{
+// /proc/acpi/button/lid/LID/state
+}
+
+void ignore_me(void)
+{
+ protect(0);
+ set_led(0);
+}
+
+int main(int argc, char **argv)
+{
+ int fd, ret;
+ struct sched_param param;
+
+ if (argc == 1)
+ ret = set_unload_heads_path("/dev/sda");
+ else if (argc == 2)
+ ret = set_unload_heads_path(argv[1]);
+ else
+ ret = -EINVAL;
+
+ if (ret || !valid_disk()) {
+ fprintf(stderr, "usage: %s <device> (default: /dev/sda)\n",
+ argv[0]);
+ exit(1);
+ }
+
+ fd = open("/dev/freefall", O_RDONLY);
+ if (fd < 0) {
+ perror("/dev/freefall");
+ return EXIT_FAILURE;
+ }
+
+ daemon(0, 0);
+ param.sched_priority = sched_get_priority_max(SCHED_FIFO);
+ sched_setscheduler(0, SCHED_FIFO, &param);
+ mlockall(MCL_CURRENT|MCL_FUTURE);
+
+ signal(SIGALRM, ignore_me);
+
+ for (;;) {
+ unsigned char count;
+
+ ret = read(fd, &count, sizeof(count));
+ alarm(0);
+ if ((ret == -1) && (errno == EINTR)) {
+ /* Alarm expired, time to unpark the heads */
+ continue;
+ }
+
+ if (ret != sizeof(count)) {
+ perror("read");
+ break;
+ }
+
+ protect(21);
+ set_led(1);
+ if (1 || on_ac() || lid_open())
+ alarm(2);
+ else
+ alarm(20);
+ }
+
+ close(fd);
+ return EXIT_SUCCESS;
+}
diff --git a/Documentation/laptops/laptop-mode.txt b/Documentation/laptops/laptop-mode.txt
new file mode 100644
index 00000000..4ebbfc3f
--- /dev/null
+++ b/Documentation/laptops/laptop-mode.txt
@@ -0,0 +1,782 @@
+How to conserve battery power using laptop-mode
+-----------------------------------------------
+
+Document Author: Bart Samwel (bart@samwel.tk)
+Date created: January 2, 2004
+Last modified: December 06, 2004
+
+Introduction
+------------
+
+Laptop mode is used to minimize the time that the hard disk needs to be spun up,
+to conserve battery power on laptops. It has been reported to cause significant
+power savings.
+
+Contents
+--------
+
+* Introduction
+* Installation
+* Caveats
+* The Details
+* Tips & Tricks
+* Control script
+* ACPI integration
+* Monitoring tool
+
+
+Installation
+------------
+
+To use laptop mode, you don't need to set any kernel configuration options
+or anything. Simply install all the files included in this document, and
+laptop mode will automatically be started when you're on battery. For
+your convenience, a tarball containing an installer can be downloaded at:
+
+http://www.samwel.tk/laptop_mode/laptop_mode/
+
+To configure laptop mode, you need to edit the configuration file, which is
+located in /etc/default/laptop-mode on Debian-based systems, or in
+/etc/sysconfig/laptop-mode on other systems.
+
+Unfortunately, automatic enabling of laptop mode does not work for
+laptops that don't have ACPI. On those laptops, you need to start laptop
+mode manually. To start laptop mode, run "laptop_mode start", and to
+stop it, run "laptop_mode stop". (Note: The laptop mode tools package now
+has experimental support for APM, you might want to try that first.)
+
+
+Caveats
+-------
+
+* The downside of laptop mode is that you have a chance of losing up to 10
+ minutes of work. If you cannot afford this, don't use it! The supplied ACPI
+ scripts automatically turn off laptop mode when the battery almost runs out,
+ so that you won't lose any data at the end of your battery life.
+
+* Most desktop hard drives have a very limited lifetime measured in spindown
+ cycles, typically about 50.000 times (it's usually listed on the spec sheet).
+ Check your drive's rating, and don't wear down your drive's lifetime if you
+ don't need to.
+
+* If you mount some of your ext3/reiserfs filesystems with the -n option, then
+ the control script will not be able to remount them correctly. You must set
+ DO_REMOUNTS=0 in the control script, otherwise it will remount them with the
+ wrong options -- or it will fail because it cannot write to /etc/mtab.
+
+* If you have your filesystems listed as type "auto" in fstab, like I did, then
+ the control script will not recognize them as filesystems that need remounting.
+ You must list the filesystems with their true type instead.
+
+* It has been reported that some versions of the mutt mail client use file access
+ times to determine whether a folder contains new mail. If you use mutt and
+ experience this, you must disable the noatime remounting by setting the option
+ DO_REMOUNT_NOATIME to 0 in the configuration file.
+
+
+The Details
+-----------
+
+Laptop mode is controlled by the knob /proc/sys/vm/laptop_mode. This knob is
+present for all kernels that have the laptop mode patch, regardless of any
+configuration options. When the knob is set, any physical disk I/O (that might
+have caused the hard disk to spin up) causes Linux to flush all dirty blocks. The
+result of this is that after a disk has spun down, it will not be spun up
+anymore to write dirty blocks, because those blocks had already been written
+immediately after the most recent read operation. The value of the laptop_mode
+knob determines the time between the occurrence of disk I/O and when the flush
+is triggered. A sensible value for the knob is 5 seconds. Setting the knob to
+0 disables laptop mode.
+
+To increase the effectiveness of the laptop_mode strategy, the laptop_mode
+control script increases dirty_expire_centisecs and dirty_writeback_centisecs in
+/proc/sys/vm to about 10 minutes (by default), which means that pages that are
+dirtied are not forced to be written to disk as often. The control script also
+changes the dirty background ratio, so that background writeback of dirty pages
+is not done anymore. Combined with a higher commit value (also 10 minutes) for
+ext3 or ReiserFS filesystems (also done automatically by the control script),
+this results in concentration of disk activity in a small time interval which
+occurs only once every 10 minutes, or whenever the disk is forced to spin up by
+a cache miss. The disk can then be spun down in the periods of inactivity.
+
+If you want to find out which process caused the disk to spin up, you can
+gather information by setting the flag /proc/sys/vm/block_dump. When this flag
+is set, Linux reports all disk read and write operations that take place, and
+all block dirtyings done to files. This makes it possible to debug why a disk
+needs to spin up, and to increase battery life even more. The output of
+block_dump is written to the kernel output, and it can be retrieved using
+"dmesg". When you use block_dump and your kernel logging level also includes
+kernel debugging messages, you probably want to turn off klogd, otherwise
+the output of block_dump will be logged, causing disk activity that is not
+normally there.
+
+
+Configuration
+-------------
+
+The laptop mode configuration file is located in /etc/default/laptop-mode on
+Debian-based systems, or in /etc/sysconfig/laptop-mode on other systems. It
+contains the following options:
+
+MAX_AGE:
+
+Maximum time, in seconds, of hard drive spindown time that you are
+comfortable with. Worst case, it's possible that you could lose this
+amount of work if your battery fails while you're in laptop mode.
+
+MINIMUM_BATTERY_MINUTES:
+
+Automatically disable laptop mode if the remaining number of minutes of
+battery power is less than this value. Default is 10 minutes.
+
+AC_HD/BATT_HD:
+
+The idle timeout that should be set on your hard drive when laptop mode
+is active (BATT_HD) and when it is not active (AC_HD). The defaults are
+20 seconds (value 4) for BATT_HD and 2 hours (value 244) for AC_HD. The
+possible values are those listed in the manual page for "hdparm" for the
+"-S" option.
+
+HD:
+
+The devices for which the spindown timeout should be adjusted by laptop mode.
+Default is /dev/hda. If you specify multiple devices, separate them by a space.
+
+READAHEAD:
+
+Disk readahead, in 512-byte sectors, while laptop mode is active. A large
+readahead can prevent disk accesses for things like executable pages (which are
+loaded on demand while the application executes) and sequentially accessed data
+(MP3s).
+
+DO_REMOUNTS:
+
+The control script automatically remounts any mounted journaled filesystems
+with appropriate commit interval options. When this option is set to 0, this
+feature is disabled.
+
+DO_REMOUNT_NOATIME:
+
+When remounting, should the filesystems be remounted with the noatime option?
+Normally, this is set to "1" (enabled), but there may be programs that require
+access time recording.
+
+DIRTY_RATIO:
+
+The percentage of memory that is allowed to contain "dirty" or unsaved data
+before a writeback is forced, while laptop mode is active. Corresponds to
+the /proc/sys/vm/dirty_ratio sysctl.
+
+DIRTY_BACKGROUND_RATIO:
+
+The percentage of memory that is allowed to contain "dirty" or unsaved data
+after a forced writeback is done due to an exceeding of DIRTY_RATIO. Set
+this nice and low. This corresponds to the /proc/sys/vm/dirty_background_ratio
+sysctl.
+
+Note that the behaviour of dirty_background_ratio is quite different
+when laptop mode is active and when it isn't. When laptop mode is inactive,
+dirty_background_ratio is the threshold percentage at which background writeouts
+start taking place. When laptop mode is active, however, background writeouts
+are disabled, and the dirty_background_ratio only determines how much writeback
+is done when dirty_ratio is reached.
+
+DO_CPU:
+
+Enable CPU frequency scaling when in laptop mode. (Requires CPUFreq to be setup.
+See Documentation/cpu-freq/user-guide.txt for more info. Disabled by default.)
+
+CPU_MAXFREQ:
+
+When on battery, what is the maximum CPU speed that the system should use? Legal
+values are "slowest" for the slowest speed that your CPU is able to operate at,
+or a value listed in /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies.
+
+
+Tips & Tricks
+-------------
+
+* Bartek Kania reports getting up to 50 minutes of extra battery life (on top
+ of his regular 3 to 3.5 hours) using a spindown time of 5 seconds (BATT_HD=1).
+
+* You can spin down the disk while playing MP3, by setting disk readahead
+ to 8MB (READAHEAD=16384). Effectively, the disk will read a complete MP3 at
+ once, and will then spin down while the MP3 is playing. (Thanks to Bartek
+ Kania.)
+
+* Drew Scott Daniels observed: "I don't know why, but when I decrease the number
+ of colours that my display uses it consumes less battery power. I've seen
+ this on powerbooks too. I hope that this is a piece of information that
+ might be useful to the Laptop Mode patch or its users."
+
+* In syslog.conf, you can prefix entries with a dash ``-'' to omit syncing the
+ file after every logging. When you're using laptop-mode and your disk doesn't
+ spin down, this is a likely culprit.
+
+* Richard Atterer observed that laptop mode does not work well with noflushd
+ (http://noflushd.sourceforge.net/), it seems that noflushd prevents laptop-mode
+ from doing its thing.
+
+* If you're worried about your data, you might want to consider using a USB
+ memory stick or something like that as a "working area". (Be aware though
+ that flash memory can only handle a limited number of writes, and overuse
+ may wear out your memory stick pretty quickly. Do _not_ use journalling
+ filesystems on flash memory sticks.)
+
+
+Configuration file for control and ACPI battery scripts
+-------------------------------------------------------
+
+This allows the tunables to be changed for the scripts via an external
+configuration file
+
+It should be installed as /etc/default/laptop-mode on Debian, and as
+/etc/sysconfig/laptop-mode on Red Hat, SUSE, Mandrake, and other work-alikes.
+
+--------------------CONFIG FILE BEGIN-------------------------------------------
+# Maximum time, in seconds, of hard drive spindown time that you are
+# comfortable with. Worst case, it's possible that you could lose this
+# amount of work if your battery fails you while in laptop mode.
+#MAX_AGE=600
+
+# Automatically disable laptop mode when the number of minutes of battery
+# that you have left goes below this threshold.
+MINIMUM_BATTERY_MINUTES=10
+
+# Read-ahead, in 512-byte sectors. You can spin down the disk while playing MP3/OGG
+# by setting the disk readahead to 8MB (READAHEAD=16384). Effectively, the disk
+# will read a complete MP3 at once, and will then spin down while the MP3/OGG is
+# playing.
+#READAHEAD=4096
+
+# Shall we remount journaled fs. with appropriate commit interval? (1=yes)
+#DO_REMOUNTS=1
+
+# And shall we add the "noatime" option to that as well? (1=yes)
+#DO_REMOUNT_NOATIME=1
+
+# Dirty synchronous ratio. At this percentage of dirty pages the process
+# which
+# calls write() does its own writeback
+#DIRTY_RATIO=40
+
+#
+# Allowed dirty background ratio, in percent. Once DIRTY_RATIO has been
+# exceeded, the kernel will wake flusher threads which will then reduce the
+# amount of dirty memory to dirty_background_ratio. Set this nice and low,
+# so once some writeout has commenced, we do a lot of it.
+#
+#DIRTY_BACKGROUND_RATIO=5
+
+# kernel default dirty buffer age
+#DEF_AGE=30
+#DEF_UPDATE=5
+#DEF_DIRTY_BACKGROUND_RATIO=10
+#DEF_DIRTY_RATIO=40
+#DEF_XFS_AGE_BUFFER=15
+#DEF_XFS_SYNC_INTERVAL=30
+#DEF_XFS_BUFD_INTERVAL=1
+
+# This must be adjusted manually to the value of HZ in the running kernel
+# on 2.4, until the XFS people change their 2.4 external interfaces to work in
+# centisecs. This can be automated, but it's a work in progress that still
+# needs# some fixes. On 2.6 kernels, XFS uses USER_HZ instead of HZ for
+# external interfaces, and that is currently always set to 100. So you don't
+# need to change this on 2.6.
+#XFS_HZ=100
+
+# Should the maximum CPU frequency be adjusted down while on battery?
+# Requires CPUFreq to be setup.
+# See Documentation/cpu-freq/user-guide.txt for more info
+#DO_CPU=0
+
+# When on battery what is the maximum CPU speed that the system should
+# use? Legal values are "slowest" for the slowest speed that your
+# CPU is able to operate at, or a value listed in:
+# /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies
+# Only applicable if DO_CPU=1.
+#CPU_MAXFREQ=slowest
+
+# Idle timeout for your hard drive (man hdparm for valid values, -S option)
+# Default is 2 hours on AC (AC_HD=244) and 20 seconds for battery (BATT_HD=4).
+#AC_HD=244
+#BATT_HD=4
+
+# The drives for which to adjust the idle timeout. Separate them by a space,
+# e.g. HD="/dev/hda /dev/hdb".
+#HD="/dev/hda"
+
+# Set the spindown timeout on a hard drive?
+#DO_HD=1
+
+--------------------CONFIG FILE END---------------------------------------------
+
+
+Control script
+--------------
+
+Please note that this control script works for the Linux 2.4 and 2.6 series (thanks
+to Kiko Piris).
+
+--------------------CONTROL SCRIPT BEGIN----------------------------------------
+#!/bin/bash
+
+# start or stop laptop_mode, best run by a power management daemon when
+# ac gets connected/disconnected from a laptop
+#
+# install as /sbin/laptop_mode
+#
+# Contributors to this script: Kiko Piris
+# Bart Samwel
+# Micha Feigin
+# Andrew Morton
+# Herve Eychenne
+# Dax Kelson
+#
+# Original Linux 2.4 version by: Jens Axboe
+
+#############################################################################
+
+# Source config
+if [ -f /etc/default/laptop-mode ] ; then
+ # Debian
+ . /etc/default/laptop-mode
+elif [ -f /etc/sysconfig/laptop-mode ] ; then
+ # Others
+ . /etc/sysconfig/laptop-mode
+fi
+
+# Don't raise an error if the config file is incomplete
+# set defaults instead:
+
+# Maximum time, in seconds, of hard drive spindown time that you are
+# comfortable with. Worst case, it's possible that you could lose this
+# amount of work if your battery fails you while in laptop mode.
+MAX_AGE=${MAX_AGE:-'600'}
+
+# Read-ahead, in kilobytes
+READAHEAD=${READAHEAD:-'4096'}
+
+# Shall we remount journaled fs. with appropriate commit interval? (1=yes)
+DO_REMOUNTS=${DO_REMOUNTS:-'1'}
+
+# And shall we add the "noatime" option to that as well? (1=yes)
+DO_REMOUNT_NOATIME=${DO_REMOUNT_NOATIME:-'1'}
+
+# Shall we adjust the idle timeout on a hard drive?
+DO_HD=${DO_HD:-'1'}
+
+# Adjust idle timeout on which hard drive?
+HD="${HD:-'/dev/hda'}"
+
+# spindown time for HD (hdparm -S values)
+AC_HD=${AC_HD:-'244'}
+BATT_HD=${BATT_HD:-'4'}
+
+# Dirty synchronous ratio. At this percentage of dirty pages the process which
+# calls write() does its own writeback
+DIRTY_RATIO=${DIRTY_RATIO:-'40'}
+
+# cpu frequency scaling
+# See Documentation/cpu-freq/user-guide.txt for more info
+DO_CPU=${CPU_MANAGE:-'0'}
+CPU_MAXFREQ=${CPU_MAXFREQ:-'slowest'}
+
+#
+# Allowed dirty background ratio, in percent. Once DIRTY_RATIO has been
+# exceeded, the kernel will wake flusher threads which will then reduce the
+# amount of dirty memory to dirty_background_ratio. Set this nice and low,
+# so once some writeout has commenced, we do a lot of it.
+#
+DIRTY_BACKGROUND_RATIO=${DIRTY_BACKGROUND_RATIO:-'5'}
+
+# kernel default dirty buffer age
+DEF_AGE=${DEF_AGE:-'30'}
+DEF_UPDATE=${DEF_UPDATE:-'5'}
+DEF_DIRTY_BACKGROUND_RATIO=${DEF_DIRTY_BACKGROUND_RATIO:-'10'}
+DEF_DIRTY_RATIO=${DEF_DIRTY_RATIO:-'40'}
+DEF_XFS_AGE_BUFFER=${DEF_XFS_AGE_BUFFER:-'15'}
+DEF_XFS_SYNC_INTERVAL=${DEF_XFS_SYNC_INTERVAL:-'30'}
+DEF_XFS_BUFD_INTERVAL=${DEF_XFS_BUFD_INTERVAL:-'1'}
+
+# This must be adjusted manually to the value of HZ in the running kernel
+# on 2.4, until the XFS people change their 2.4 external interfaces to work in
+# centisecs. This can be automated, but it's a work in progress that still needs
+# some fixes. On 2.6 kernels, XFS uses USER_HZ instead of HZ for external
+# interfaces, and that is currently always set to 100. So you don't need to
+# change this on 2.6.
+XFS_HZ=${XFS_HZ:-'100'}
+
+#############################################################################
+
+KLEVEL="$(uname -r |
+ {
+ IFS='.' read a b c
+ echo $a.$b
+ }
+)"
+case "$KLEVEL" in
+ "2.4"|"2.6")
+ ;;
+ *)
+ echo "Unhandled kernel version: $KLEVEL ('uname -r' = '$(uname -r)')" >&2
+ exit 1
+ ;;
+esac
+
+if [ ! -e /proc/sys/vm/laptop_mode ] ; then
+ echo "Kernel is not patched with laptop_mode patch." >&2
+ exit 1
+fi
+
+if [ ! -w /proc/sys/vm/laptop_mode ] ; then
+ echo "You do not have enough privileges to enable laptop_mode." >&2
+ exit 1
+fi
+
+# Remove an option (the first parameter) of the form option=<number> from
+# a mount options string (the rest of the parameters).
+parse_mount_opts () {
+ OPT="$1"
+ shift
+ echo ",$*," | sed \
+ -e 's/,'"$OPT"'=[0-9]*,/,/g' \
+ -e 's/,,*/,/g' \
+ -e 's/^,//' \
+ -e 's/,$//'
+}
+
+# Remove an option (the first parameter) without any arguments from
+# a mount option string (the rest of the parameters).
+parse_nonumber_mount_opts () {
+ OPT="$1"
+ shift
+ echo ",$*," | sed \
+ -e 's/,'"$OPT"',/,/g' \
+ -e 's/,,*/,/g' \
+ -e 's/^,//' \
+ -e 's/,$//'
+}
+
+# Find out the state of a yes/no option (e.g. "atime"/"noatime") in
+# fstab for a given filesystem, and use this state to replace the
+# value of the option in another mount options string. The device
+# is the first argument, the option name the second, and the default
+# value the third. The remainder is the mount options string.
+#
+# Example:
+# parse_yesno_opts_wfstab /dev/hda1 atime atime defaults,noatime
+#
+# If fstab contains, say, "rw" for this filesystem, then the result
+# will be "defaults,atime".
+parse_yesno_opts_wfstab () {
+ L_DEV="$1"
+ OPT="$2"
+ DEF_OPT="$3"
+ shift 3
+ L_OPTS="$*"
+ PARSEDOPTS1="$(parse_nonumber_mount_opts $OPT $L_OPTS)"
+ PARSEDOPTS1="$(parse_nonumber_mount_opts no$OPT $PARSEDOPTS1)"
+ # Watch for a default atime in fstab
+ FSTAB_OPTS="$(awk '$1 == "'$L_DEV'" { print $4 }' /etc/fstab)"
+ if echo "$FSTAB_OPTS" | grep "$OPT" > /dev/null ; then
+ # option specified in fstab: extract the value and use it
+ if echo "$FSTAB_OPTS" | grep "no$OPT" > /dev/null ; then
+ echo "$PARSEDOPTS1,no$OPT"
+ else
+ # no$OPT not found -- so we must have $OPT.
+ echo "$PARSEDOPTS1,$OPT"
+ fi
+ else
+ # option not specified in fstab -- choose the default.
+ echo "$PARSEDOPTS1,$DEF_OPT"
+ fi
+}
+
+# Find out the state of a numbered option (e.g. "commit=NNN") in
+# fstab for a given filesystem, and use this state to replace the
+# value of the option in another mount options string. The device
+# is the first argument, and the option name the second. The
+# remainder is the mount options string in which the replacement
+# must be done.
+#
+# Example:
+# parse_mount_opts_wfstab /dev/hda1 commit defaults,commit=7
+#
+# If fstab contains, say, "commit=3,rw" for this filesystem, then the
+# result will be "rw,commit=3".
+parse_mount_opts_wfstab () {
+ L_DEV="$1"
+ OPT="$2"
+ shift 2
+ L_OPTS="$*"
+ PARSEDOPTS1="$(parse_mount_opts $OPT $L_OPTS)"
+ # Watch for a default commit in fstab
+ FSTAB_OPTS="$(awk '$1 == "'$L_DEV'" { print $4 }' /etc/fstab)"
+ if echo "$FSTAB_OPTS" | grep "$OPT=" > /dev/null ; then
+ # option specified in fstab: extract the value, and use it
+ echo -n "$PARSEDOPTS1,$OPT="
+ echo ",$FSTAB_OPTS," | sed \
+ -e 's/.*,'"$OPT"'=//' \
+ -e 's/,.*//'
+ else
+ # option not specified in fstab: set it to 0
+ echo "$PARSEDOPTS1,$OPT=0"
+ fi
+}
+
+deduce_fstype () {
+ MP="$1"
+ # My root filesystem unfortunately has
+ # type "unknown" in /etc/mtab. If we encounter
+ # "unknown", we try to get the type from fstab.
+ cat /etc/fstab |
+ grep -v '^#' |
+ while read FSTAB_DEV FSTAB_MP FSTAB_FST FSTAB_OPTS FSTAB_DUMP FSTAB_DUMP ; do
+ if [ "$FSTAB_MP" = "$MP" ]; then
+ echo $FSTAB_FST
+ exit 0
+ fi
+ done
+}
+
+if [ $DO_REMOUNT_NOATIME -eq 1 ] ; then
+ NOATIME_OPT=",noatime"
+fi
+
+case "$1" in
+ start)
+ AGE=$((100*$MAX_AGE))
+ XFS_AGE=$(($XFS_HZ*$MAX_AGE))
+ echo -n "Starting laptop_mode"
+
+ if [ -d /proc/sys/vm/pagebuf ] ; then
+ # (For 2.4 and early 2.6.)
+ # This only needs to be set, not reset -- it is only used when
+ # laptop mode is enabled.
+ echo $XFS_AGE > /proc/sys/vm/pagebuf/lm_flush_age
+ echo $XFS_AGE > /proc/sys/fs/xfs/lm_sync_interval
+ elif [ -f /proc/sys/fs/xfs/lm_age_buffer ] ; then
+ # (A couple of early 2.6 laptop mode patches had these.)
+ # The same goes for these.
+ echo $XFS_AGE > /proc/sys/fs/xfs/lm_age_buffer
+ echo $XFS_AGE > /proc/sys/fs/xfs/lm_sync_interval
+ elif [ -f /proc/sys/fs/xfs/age_buffer ] ; then
+ # (2.6.6)
+ # But not for these -- they are also used in normal
+ # operation.
+ echo $XFS_AGE > /proc/sys/fs/xfs/age_buffer
+ echo $XFS_AGE > /proc/sys/fs/xfs/sync_interval
+ elif [ -f /proc/sys/fs/xfs/age_buffer_centisecs ] ; then
+ # (2.6.7 upwards)
+ # And not for these either. These are in centisecs,
+ # not USER_HZ, so we have to use $AGE, not $XFS_AGE.
+ echo $AGE > /proc/sys/fs/xfs/age_buffer_centisecs
+ echo $AGE > /proc/sys/fs/xfs/xfssyncd_centisecs
+ echo 3000 > /proc/sys/fs/xfs/xfsbufd_centisecs
+ fi
+
+ case "$KLEVEL" in
+ "2.4")
+ echo 1 > /proc/sys/vm/laptop_mode
+ echo "30 500 0 0 $AGE $AGE 60 20 0" > /proc/sys/vm/bdflush
+ ;;
+ "2.6")
+ echo 5 > /proc/sys/vm/laptop_mode
+ echo "$AGE" > /proc/sys/vm/dirty_writeback_centisecs
+ echo "$AGE" > /proc/sys/vm/dirty_expire_centisecs
+ echo "$DIRTY_RATIO" > /proc/sys/vm/dirty_ratio
+ echo "$DIRTY_BACKGROUND_RATIO" > /proc/sys/vm/dirty_background_ratio
+ ;;
+ esac
+ if [ $DO_REMOUNTS -eq 1 ]; then
+ cat /etc/mtab | while read DEV MP FST OPTS DUMP PASS ; do
+ PARSEDOPTS="$(parse_mount_opts "$OPTS")"
+ if [ "$FST" = 'unknown' ]; then
+ FST=$(deduce_fstype $MP)
+ fi
+ case "$FST" in
+ "ext3"|"reiserfs")
+ PARSEDOPTS="$(parse_mount_opts commit "$OPTS")"
+ mount $DEV -t $FST $MP -o remount,$PARSEDOPTS,commit=$MAX_AGE$NOATIME_OPT
+ ;;
+ "xfs")
+ mount $DEV -t $FST $MP -o remount,$OPTS$NOATIME_OPT
+ ;;
+ esac
+ if [ -b $DEV ] ; then
+ blockdev --setra $(($READAHEAD * 2)) $DEV
+ fi
+ done
+ fi
+ if [ $DO_HD -eq 1 ] ; then
+ for THISHD in $HD ; do
+ /sbin/hdparm -S $BATT_HD $THISHD > /dev/null 2>&1
+ /sbin/hdparm -B 1 $THISHD > /dev/null 2>&1
+ done
+ fi
+ if [ $DO_CPU -eq 1 -a -e /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq ]; then
+ if [ $CPU_MAXFREQ = 'slowest' ]; then
+ CPU_MAXFREQ=`cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq`
+ fi
+ echo $CPU_MAXFREQ > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
+ fi
+ echo "."
+ ;;
+ stop)
+ U_AGE=$((100*$DEF_UPDATE))
+ B_AGE=$((100*$DEF_AGE))
+ echo -n "Stopping laptop_mode"
+ echo 0 > /proc/sys/vm/laptop_mode
+ if [ -f /proc/sys/fs/xfs/age_buffer -a ! -f /proc/sys/fs/xfs/lm_age_buffer ] ; then
+ # These need to be restored, if there are no lm_*.
+ echo $(($XFS_HZ*$DEF_XFS_AGE_BUFFER)) > /proc/sys/fs/xfs/age_buffer
+ echo $(($XFS_HZ*$DEF_XFS_SYNC_INTERVAL)) > /proc/sys/fs/xfs/sync_interval
+ elif [ -f /proc/sys/fs/xfs/age_buffer_centisecs ] ; then
+ # These need to be restored as well.
+ echo $((100*$DEF_XFS_AGE_BUFFER)) > /proc/sys/fs/xfs/age_buffer_centisecs
+ echo $((100*$DEF_XFS_SYNC_INTERVAL)) > /proc/sys/fs/xfs/xfssyncd_centisecs
+ echo $((100*$DEF_XFS_BUFD_INTERVAL)) > /proc/sys/fs/xfs/xfsbufd_centisecs
+ fi
+ case "$KLEVEL" in
+ "2.4")
+ echo "30 500 0 0 $U_AGE $B_AGE 60 20 0" > /proc/sys/vm/bdflush
+ ;;
+ "2.6")
+ echo "$U_AGE" > /proc/sys/vm/dirty_writeback_centisecs
+ echo "$B_AGE" > /proc/sys/vm/dirty_expire_centisecs
+ echo "$DEF_DIRTY_RATIO" > /proc/sys/vm/dirty_ratio
+ echo "$DEF_DIRTY_BACKGROUND_RATIO" > /proc/sys/vm/dirty_background_ratio
+ ;;
+ esac
+ if [ $DO_REMOUNTS -eq 1 ] ; then
+ cat /etc/mtab | while read DEV MP FST OPTS DUMP PASS ; do
+ # Reset commit and atime options to defaults.
+ if [ "$FST" = 'unknown' ]; then
+ FST=$(deduce_fstype $MP)
+ fi
+ case "$FST" in
+ "ext3"|"reiserfs")
+ PARSEDOPTS="$(parse_mount_opts_wfstab $DEV commit $OPTS)"
+ PARSEDOPTS="$(parse_yesno_opts_wfstab $DEV atime atime $PARSEDOPTS)"
+ mount $DEV -t $FST $MP -o remount,$PARSEDOPTS
+ ;;
+ "xfs")
+ PARSEDOPTS="$(parse_yesno_opts_wfstab $DEV atime atime $OPTS)"
+ mount $DEV -t $FST $MP -o remount,$PARSEDOPTS
+ ;;
+ esac
+ if [ -b $DEV ] ; then
+ blockdev --setra 256 $DEV
+ fi
+ done
+ fi
+ if [ $DO_HD -eq 1 ] ; then
+ for THISHD in $HD ; do
+ /sbin/hdparm -S $AC_HD $THISHD > /dev/null 2>&1
+ /sbin/hdparm -B 255 $THISHD > /dev/null 2>&1
+ done
+ fi
+ if [ $DO_CPU -eq 1 -a -e /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq ]; then
+ echo `cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq` > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
+ fi
+ echo "."
+ ;;
+ *)
+ echo "Usage: $0 {start|stop}" 2>&1
+ exit 1
+ ;;
+
+esac
+
+exit 0
+--------------------CONTROL SCRIPT END------------------------------------------
+
+
+ACPI integration
+----------------
+
+Dax Kelson submitted this so that the ACPI acpid daemon will
+kick off the laptop_mode script and run hdparm. The part that
+automatically disables laptop mode when the battery is low was
+written by Jan Topinski.
+
+-----------------/etc/acpi/events/ac_adapter BEGIN------------------------------
+event=ac_adapter
+action=/etc/acpi/actions/ac.sh %e
+----------------/etc/acpi/events/ac_adapter END---------------------------------
+
+
+-----------------/etc/acpi/events/battery BEGIN---------------------------------
+event=battery.*
+action=/etc/acpi/actions/battery.sh %e
+----------------/etc/acpi/events/battery END------------------------------------
+
+
+----------------/etc/acpi/actions/ac.sh BEGIN-----------------------------------
+#!/bin/bash
+
+# ac on/offline event handler
+
+status=`awk '/^state: / { print $2 }' /proc/acpi/ac_adapter/$2/state`
+
+case $status in
+ "on-line")
+ /sbin/laptop_mode stop
+ exit 0
+ ;;
+ "off-line")
+ /sbin/laptop_mode start
+ exit 0
+ ;;
+esac
+---------------------------/etc/acpi/actions/ac.sh END--------------------------
+
+
+---------------------------/etc/acpi/actions/battery.sh BEGIN-------------------
+#! /bin/bash
+
+# Automatically disable laptop mode when the battery almost runs out.
+
+BATT_INFO=/proc/acpi/battery/$2/state
+
+if [[ -f /proc/sys/vm/laptop_mode ]]
+then
+ LM=`cat /proc/sys/vm/laptop_mode`
+ if [[ $LM -gt 0 ]]
+ then
+ if [[ -f $BATT_INFO ]]
+ then
+ # Source the config file only now that we know we need
+ if [ -f /etc/default/laptop-mode ] ; then
+ # Debian
+ . /etc/default/laptop-mode
+ elif [ -f /etc/sysconfig/laptop-mode ] ; then
+ # Others
+ . /etc/sysconfig/laptop-mode
+ fi
+ MINIMUM_BATTERY_MINUTES=${MINIMUM_BATTERY_MINUTES:-'10'}
+
+ ACTION="`cat $BATT_INFO | grep charging | cut -c 26-`"
+ if [[ ACTION -eq "discharging" ]]
+ then
+ PRESENT_RATE=`cat $BATT_INFO | grep "present rate:" | sed "s/.* \([0-9][0-9]* \).*/\1/" `
+ REMAINING=`cat $BATT_INFO | grep "remaining capacity:" | sed "s/.* \([0-9][0-9]* \).*/\1/" `
+ fi
+ if (($REMAINING * 60 / $PRESENT_RATE < $MINIMUM_BATTERY_MINUTES))
+ then
+ /sbin/laptop_mode stop
+ fi
+ else
+ logger -p daemon.warning "You are using laptop mode and your battery interface $BATT_INFO is missing. This may lead to loss of data when the battery runs out. Check kernel ACPI support and /proc/acpi/battery folder, and edit /etc/acpi/battery.sh to set BATT_INFO to the correct path."
+ fi
+ fi
+fi
+---------------------------/etc/acpi/actions/battery.sh END--------------------
+
+
+Monitoring tool
+---------------
+
+Bartek Kania submitted this, it can be used to measure how much time your disk
+spends spun up/down. See Documentation/laptops/dslm.c
diff --git a/Documentation/laptops/sony-laptop.txt b/Documentation/laptops/sony-laptop.txt
new file mode 100644
index 00000000..0d5ac7f5
--- /dev/null
+++ b/Documentation/laptops/sony-laptop.txt
@@ -0,0 +1,144 @@
+Sony Notebook Control Driver (SNC) Readme
+-----------------------------------------
+ Copyright (C) 2004- 2005 Stelian Pop <stelian@popies.net>
+ Copyright (C) 2007 Mattia Dongili <malattia@linux.it>
+
+This mini-driver drives the SNC and SPIC device present in the ACPI BIOS of the
+Sony Vaio laptops. This driver mixes both devices functions under the same
+(hopefully consistent) interface. This also means that the sonypi driver is
+obsoleted by sony-laptop now.
+
+Fn keys (hotkeys):
+------------------
+Some models report hotkeys through the SNC or SPIC devices, such events are
+reported both through the ACPI subsystem as acpi events and through the INPUT
+subsystem. See the logs of acpid or /proc/acpi/event and
+/proc/bus/input/devices to find out what those events are and which input
+devices are created by the driver. Additionally, loading the driver with the
+debug option will report all events in the kernel log.
+
+The "scancodes" passed to the input system (that can be remapped with udev)
+are indexes to the table "sony_laptop_input_keycode_map" in the sony-laptop.c
+module. For example the "FN/E" key combination (EJECTCD on some models)
+generates the scancode 20 (0x14).
+
+Backlight control:
+------------------
+If your laptop model supports it, you will find sysfs files in the
+/sys/class/backlight/sony/
+directory. You will be able to query and set the current screen
+brightness:
+ brightness get/set screen brightness (an integer
+ between 0 and 7)
+ actual_brightness reading from this file will query the HW
+ to get real brightness value
+ max_brightness the maximum brightness value
+
+
+Platform specific:
+------------------
+Loading the sony-laptop module will create a
+/sys/devices/platform/sony-laptop/
+directory populated with some files.
+
+You then read/write integer values from/to those files by using
+standard UNIX tools.
+
+The files are:
+ brightness_default screen brightness which will be set
+ when the laptop will be rebooted
+ cdpower power on/off the internal CD drive
+ audiopower power on/off the internal sound card
+ lanpower power on/off the internal ethernet card
+ (only in debug mode)
+ bluetoothpower power on/off the internal bluetooth device
+ fanspeed get/set the fan speed
+
+Note that some files may be missing if they are not supported
+by your particular laptop model.
+
+Example usage:
+ # echo "1" > /sys/devices/platform/sony-laptop/brightness_default
+sets the lowest screen brightness for the next and later reboots,
+ # echo "8" > /sys/devices/platform/sony-laptop/brightness_default
+sets the highest screen brightness for the next and later reboots,
+ # cat /sys/devices/platform/sony-laptop/brightness_default
+retrieves the value.
+
+ # echo "0" > /sys/devices/platform/sony-laptop/audiopower
+powers off the sound card,
+ # echo "1" > /sys/devices/platform/sony-laptop/audiopower
+powers on the sound card.
+
+
+RFkill control:
+---------------
+More recent Vaio models expose a consistent set of ACPI methods to
+control radio frequency emitting devices. If you are a lucky owner of
+such a laptop you will find the necessary rfkill devices under
+/sys/class/rfkill. Check those starting with sony-* in
+ # grep . /sys/class/rfkill/*/{state,name}
+
+
+Development:
+------------
+
+If you want to help with the development of this driver (and
+you are not afraid of any side effects doing strange things with
+your ACPI BIOS could have on your laptop), load the driver and
+pass the option 'debug=1'.
+
+REPEAT: DON'T DO THIS IF YOU DON'T LIKE RISKY BUSINESS.
+
+In your kernel logs you will find the list of all ACPI methods
+the SNC device has on your laptop.
+
+* For new models you will see a long list of meaningless method names,
+reading the DSDT table source should reveal that:
+(1) the SNC device uses an internal capability lookup table
+(2) SN00 is used to find values in the lookup table
+(3) SN06 and SN07 are used to call into the real methods based on
+ offsets you can obtain iterating the table using SN00
+(4) SN02 used to enable events.
+Some values in the capability lookup table are more or less known, see
+the code for all sony_call_snc_handle calls, others are more obscure.
+
+* For old models you can see the GCDP/GCDP methods used to pwer on/off
+the CD drive, but there are others and they are usually different from
+model to model.
+
+I HAVE NO IDEA WHAT THOSE METHODS DO.
+
+The sony-laptop driver creates, for some of those methods (the most
+current ones found on several Vaio models), an entry under
+/sys/devices/platform/sony-laptop, just like the 'cdpower' one.
+You can create other entries corresponding to your own laptop methods by
+further editing the source (see the 'sony_nc_values' table, and add a new
+entry to this table with your get/set method names using the
+SNC_HANDLE_NAMES macro).
+
+Your mission, should you accept it, is to try finding out what
+those entries are for, by reading/writing random values from/to those
+files and find out what is the impact on your laptop.
+
+Should you find anything interesting, please report it back to me,
+I will not disavow all knowledge of your actions :)
+
+See also http://www.linux.it/~malattia/wiki/index.php/Sony_drivers for other
+useful info.
+
+Bugs/Limitations:
+-----------------
+
+* This driver is not based on official documentation from Sony
+ (because there is none), so there is no guarantee this driver
+ will work at all, or do the right thing. Although this hasn't
+ happened to me, this driver could do very bad things to your
+ laptop, including permanent damage.
+
+* The sony-laptop and sonypi drivers do not interact at all. In the
+ future, sonypi will be removed and replaced by sony-laptop.
+
+* spicctrl, which is the userspace tool used to communicate with the
+ sonypi driver (through /dev/sonypi) is deprecated as well since all
+ its features are now available under the sysfs tree via sony-laptop.
diff --git a/Documentation/laptops/sonypi.txt b/Documentation/laptops/sonypi.txt
new file mode 100644
index 00000000..606bdb9c
--- /dev/null
+++ b/Documentation/laptops/sonypi.txt
@@ -0,0 +1,152 @@
+Sony Programmable I/O Control Device Driver Readme
+--------------------------------------------------
+ Copyright (C) 2001-2004 Stelian Pop <stelian@popies.net>
+ Copyright (C) 2001-2002 AlcĂ´ve <www.alcove.com>
+ Copyright (C) 2001 Michael Ashley <m.ashley@unsw.edu.au>
+ Copyright (C) 2001 Junichi Morita <jun1m@mars.dti.ne.jp>
+ Copyright (C) 2000 Takaya Kinjo <t-kinjo@tc4.so-net.ne.jp>
+ Copyright (C) 2000 Andrew Tridgell <tridge@samba.org>
+
+This driver enables access to the Sony Programmable I/O Control Device which
+can be found in many Sony Vaio laptops. Some newer Sony laptops (seems to be
+limited to new FX series laptops, at least the FX501 and the FX702) lack a
+sonypi device and are not supported at all by this driver.
+
+It will give access (through a user space utility) to some events those laptops
+generate, like:
+ - jogdial events (the small wheel on the side of Vaios)
+ - capture button events (only on Vaio Picturebook series)
+ - Fn keys
+ - bluetooth button (only on C1VR model)
+ - programmable keys, back, help, zoom, thumbphrase buttons, etc.
+ (when available)
+
+Those events (see linux/sonypi.h) can be polled using the character device node
+/dev/sonypi (major 10, minor auto allocated or specified as a option).
+A simple daemon which translates the jogdial movements into mouse wheel events
+can be downloaded at: <http://popies.net/sonypi/>
+
+Another option to intercept the events is to get them directly through the
+input layer.
+
+This driver supports also some ioctl commands for setting the LCD screen
+brightness and querying the batteries charge information (some more
+commands may be added in the future).
+
+This driver can also be used to set the camera controls on Picturebook series
+(brightness, contrast etc), and is used by the video4linux driver for the
+Motion Eye camera.
+
+Please note that this driver was created by reverse engineering the Windows
+driver and the ACPI BIOS, because Sony doesn't agree to release any programming
+specs for its laptops. If someone convinces them to do so, drop me a note.
+
+Driver options:
+---------------
+
+Several options can be passed to the sonypi driver using the standard
+module argument syntax (<param>=<value> when passing the option to the
+module or sonypi.<param>=<value> on the kernel boot line when sonypi is
+statically linked into the kernel). Those options are:
+
+ minor: minor number of the misc device /dev/sonypi,
+ default is -1 (automatic allocation, see /proc/misc
+ or kernel logs)
+
+ camera: if you have a PictureBook series Vaio (with the
+ integrated MotionEye camera), set this parameter to 1
+ in order to let the driver access to the camera
+
+ fnkeyinit: on some Vaios (C1VE, C1VR etc), the Fn key events don't
+ get enabled unless you set this parameter to 1.
+ Do not use this option unless it's actually necessary,
+ some Vaio models don't deal well with this option.
+ This option is available only if the kernel is
+ compiled without ACPI support (since it conflicts
+ with it and it shouldn't be required anyway if
+ ACPI is already enabled).
+
+ verbose: set to 1 to print unknown events received from the
+ sonypi device.
+ set to 2 to print all events received from the
+ sonypi device.
+
+ compat: uses some compatibility code for enabling the sonypi
+ events. If the driver worked for you in the past
+ (prior to version 1.5) and does not work anymore,
+ add this option and report to the author.
+
+ mask: event mask telling the driver what events will be
+ reported to the user. This parameter is required for
+ some Vaio models where the hardware reuses values
+ used in other Vaio models (like the FX series who does
+ not have a jogdial but reuses the jogdial events for
+ programmable keys events). The default event mask is
+ set to 0xffffffff, meaning that all possible events
+ will be tried. You can use the following bits to
+ construct your own event mask (from
+ drivers/char/sonypi.h):
+ SONYPI_JOGGER_MASK 0x0001
+ SONYPI_CAPTURE_MASK 0x0002
+ SONYPI_FNKEY_MASK 0x0004
+ SONYPI_BLUETOOTH_MASK 0x0008
+ SONYPI_PKEY_MASK 0x0010
+ SONYPI_BACK_MASK 0x0020
+ SONYPI_HELP_MASK 0x0040
+ SONYPI_LID_MASK 0x0080
+ SONYPI_ZOOM_MASK 0x0100
+ SONYPI_THUMBPHRASE_MASK 0x0200
+ SONYPI_MEYE_MASK 0x0400
+ SONYPI_MEMORYSTICK_MASK 0x0800
+ SONYPI_BATTERY_MASK 0x1000
+ SONYPI_WIRELESS_MASK 0x2000
+
+ useinput: if set (which is the default) two input devices are
+ created, one which interprets the jogdial events as
+ mouse events, the other one which acts like a
+ keyboard reporting the pressing of the special keys.
+
+Module use:
+-----------
+
+In order to automatically load the sonypi module on use, you can put those
+lines a configuration file in /etc/modprobe.d/:
+
+ alias char-major-10-250 sonypi
+ options sonypi minor=250
+
+This supposes the use of minor 250 for the sonypi device:
+
+ # mknod /dev/sonypi c 10 250
+
+Bugs:
+-----
+
+ - several users reported that this driver disables the BIOS-managed
+ Fn-keys which put the laptop in sleeping state, or switch the
+ external monitor on/off. There is no workaround yet, since this
+ driver disables all APM management for those keys, by enabling the
+ ACPI management (and the ACPI core stuff is not complete yet). If
+ you have one of those laptops with working Fn keys and want to
+ continue to use them, don't use this driver.
+
+ - some users reported that the laptop speed is lower (dhrystone
+ tested) when using the driver with the fnkeyinit parameter. I cannot
+ reproduce it on my laptop and not all users have this problem.
+ This happens because the fnkeyinit parameter enables the ACPI
+ mode (but without additional ACPI control, like processor
+ speed handling etc). Use ACPI instead of APM if it works on your
+ laptop.
+
+ - sonypi lacks the ability to distinguish between certain key
+ events on some models.
+
+ - some models with the nvidia card (geforce go 6200 tc) uses a
+ different way to adjust the backlighting of the screen. There
+ is a userspace utility to adjust the brightness on those models,
+ which can be downloaded from
+ http://www.acc.umu.se/~erikw/program/smartdimmer-0.1.tar.bz2
+
+ - since all development was done by reverse engineering, there is
+ _absolutely no guarantee_ that this driver will not crash your
+ laptop. Permanently.
diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt
new file mode 100644
index 00000000..cf7bc6cb
--- /dev/null
+++ b/Documentation/laptops/thinkpad-acpi.txt
@@ -0,0 +1,1519 @@
+ ThinkPad ACPI Extras Driver
+
+ Version 0.24
+ December 11th, 2009
+
+ Borislav Deianov <borislav@users.sf.net>
+ Henrique de Moraes Holschuh <hmh@hmh.eng.br>
+ http://ibm-acpi.sf.net/
+
+
+This is a Linux driver for the IBM and Lenovo ThinkPad laptops. It
+supports various features of these laptops which are accessible
+through the ACPI and ACPI EC framework, but not otherwise fully
+supported by the generic Linux ACPI drivers.
+
+This driver used to be named ibm-acpi until kernel 2.6.21 and release
+0.13-20070314. It used to be in the drivers/acpi tree, but it was
+moved to the drivers/misc tree and renamed to thinkpad-acpi for kernel
+2.6.22, and release 0.14. It was moved to drivers/platform/x86 for
+kernel 2.6.29 and release 0.22.
+
+The driver is named "thinkpad-acpi". In some places, like module
+names and log messages, "thinkpad_acpi" is used because of userspace
+issues.
+
+"tpacpi" is used as a shorthand where "thinkpad-acpi" would be too
+long due to length limitations on some Linux kernel versions.
+
+Status
+------
+
+The features currently supported are the following (see below for
+detailed description):
+
+ - Fn key combinations
+ - Bluetooth enable and disable
+ - video output switching, expansion control
+ - ThinkLight on and off
+ - CMOS/UCMS control
+ - LED control
+ - ACPI sounds
+ - temperature sensors
+ - Experimental: embedded controller register dump
+ - LCD brightness control
+ - Volume control
+ - Fan control and monitoring: fan speed, fan enable/disable
+ - WAN enable and disable
+ - UWB enable and disable
+
+A compatibility table by model and feature is maintained on the web
+site, http://ibm-acpi.sf.net/. I appreciate any success or failure
+reports, especially if they add to or correct the compatibility table.
+Please include the following information in your report:
+
+ - ThinkPad model name
+ - a copy of your ACPI tables, using the "acpidump" utility
+ - a copy of the output of dmidecode, with serial numbers
+ and UUIDs masked off
+ - which driver features work and which don't
+ - the observed behavior of non-working features
+
+Any other comments or patches are also more than welcome.
+
+
+Installation
+------------
+
+If you are compiling this driver as included in the Linux kernel
+sources, look for the CONFIG_THINKPAD_ACPI Kconfig option.
+It is located on the menu path: "Device Drivers" -> "X86 Platform
+Specific Device Drivers" -> "ThinkPad ACPI Laptop Extras".
+
+
+Features
+--------
+
+The driver exports two different interfaces to userspace, which can be
+used to access the features it provides. One is a legacy procfs-based
+interface, which will be removed at some time in the future. The other
+is a new sysfs-based interface which is not complete yet.
+
+The procfs interface creates the /proc/acpi/ibm directory. There is a
+file under that directory for each feature it supports. The procfs
+interface is mostly frozen, and will change very little if at all: it
+will not be extended to add any new functionality in the driver, instead
+all new functionality will be implemented on the sysfs interface.
+
+The sysfs interface tries to blend in the generic Linux sysfs subsystems
+and classes as much as possible. Since some of these subsystems are not
+yet ready or stabilized, it is expected that this interface will change,
+and any and all userspace programs must deal with it.
+
+
+Notes about the sysfs interface:
+
+Unlike what was done with the procfs interface, correctness when talking
+to the sysfs interfaces will be enforced, as will correctness in the
+thinkpad-acpi's implementation of sysfs interfaces.
+
+Also, any bugs in the thinkpad-acpi sysfs driver code or in the
+thinkpad-acpi's implementation of the sysfs interfaces will be fixed for
+maximum correctness, even if that means changing an interface in
+non-compatible ways. As these interfaces mature both in the kernel and
+in thinkpad-acpi, such changes should become quite rare.
+
+Applications interfacing to the thinkpad-acpi sysfs interfaces must
+follow all sysfs guidelines and correctly process all errors (the sysfs
+interface makes extensive use of errors). File descriptors and open /
+close operations to the sysfs inodes must also be properly implemented.
+
+The version of thinkpad-acpi's sysfs interface is exported by the driver
+as a driver attribute (see below).
+
+Sysfs driver attributes are on the driver's sysfs attribute space,
+for 2.6.23+ this is /sys/bus/platform/drivers/thinkpad_acpi/ and
+/sys/bus/platform/drivers/thinkpad_hwmon/
+
+Sysfs device attributes are on the thinkpad_acpi device sysfs attribute
+space, for 2.6.23+ this is /sys/devices/platform/thinkpad_acpi/.
+
+Sysfs device attributes for the sensors and fan are on the
+thinkpad_hwmon device's sysfs attribute space, but you should locate it
+looking for a hwmon device with the name attribute of "thinkpad", or
+better yet, through libsensors.
+
+
+Driver version
+--------------
+
+procfs: /proc/acpi/ibm/driver
+sysfs driver attribute: version
+
+The driver name and version. No commands can be written to this file.
+
+
+Sysfs interface version
+-----------------------
+
+sysfs driver attribute: interface_version
+
+Version of the thinkpad-acpi sysfs interface, as an unsigned long
+(output in hex format: 0xAAAABBCC), where:
+ AAAA - major revision
+ BB - minor revision
+ CC - bugfix revision
+
+The sysfs interface version changelog for the driver can be found at the
+end of this document. Changes to the sysfs interface done by the kernel
+subsystems are not documented here, nor are they tracked by this
+attribute.
+
+Changes to the thinkpad-acpi sysfs interface are only considered
+non-experimental when they are submitted to Linux mainline, at which
+point the changes in this interface are documented and interface_version
+may be updated. If you are using any thinkpad-acpi features not yet
+sent to mainline for merging, you do so on your own risk: these features
+may disappear, or be implemented in a different and incompatible way by
+the time they are merged in Linux mainline.
+
+Changes that are backwards-compatible by nature (e.g. the addition of
+attributes that do not change the way the other attributes work) do not
+always warrant an update of interface_version. Therefore, one must
+expect that an attribute might not be there, and deal with it properly
+(an attribute not being there *is* a valid way to make it clear that a
+feature is not available in sysfs).
+
+
+Hot keys
+--------
+
+procfs: /proc/acpi/ibm/hotkey
+sysfs device attribute: hotkey_*
+
+In a ThinkPad, the ACPI HKEY handler is responsible for communicating
+some important events and also keyboard hot key presses to the operating
+system. Enabling the hotkey functionality of thinkpad-acpi signals the
+firmware that such a driver is present, and modifies how the ThinkPad
+firmware will behave in many situations.
+
+The driver enables the HKEY ("hot key") event reporting automatically
+when loaded, and disables it when it is removed.
+
+The driver will report HKEY events in the following format:
+
+ ibm/hotkey HKEY 00000080 0000xxxx
+
+Some of these events refer to hot key presses, but not all of them.
+
+The driver will generate events over the input layer for hot keys and
+radio switches, and over the ACPI netlink layer for other events. The
+input layer support accepts the standard IOCTLs to remap the keycodes
+assigned to each hot key.
+
+The hot key bit mask allows some control over which hot keys generate
+events. If a key is "masked" (bit set to 0 in the mask), the firmware
+will handle it. If it is "unmasked", it signals the firmware that
+thinkpad-acpi would prefer to handle it, if the firmware would be so
+kind to allow it (and it often doesn't!).
+
+Not all bits in the mask can be modified. Not all bits that can be
+modified do anything. Not all hot keys can be individually controlled
+by the mask. Some models do not support the mask at all. The behaviour
+of the mask is, therefore, highly dependent on the ThinkPad model.
+
+The driver will filter out any unmasked hotkeys, so even if the firmware
+doesn't allow disabling an specific hotkey, the driver will not report
+events for unmasked hotkeys.
+
+Note that unmasking some keys prevents their default behavior. For
+example, if Fn+F5 is unmasked, that key will no longer enable/disable
+Bluetooth by itself in firmware.
+
+Note also that not all Fn key combinations are supported through ACPI
+depending on the ThinkPad model and firmware version. On those
+ThinkPads, it is still possible to support some extra hotkeys by
+polling the "CMOS NVRAM" at least 10 times per second. The driver
+attempts to enables this functionality automatically when required.
+
+procfs notes:
+
+The following commands can be written to the /proc/acpi/ibm/hotkey file:
+
+ echo 0xffffffff > /proc/acpi/ibm/hotkey -- enable all hot keys
+ echo 0 > /proc/acpi/ibm/hotkey -- disable all possible hot keys
+ ... any other 8-hex-digit mask ...
+ echo reset > /proc/acpi/ibm/hotkey -- restore the recommended mask
+
+The following commands have been deprecated and will cause the kernel
+to log a warning:
+
+ echo enable > /proc/acpi/ibm/hotkey -- does nothing
+ echo disable > /proc/acpi/ibm/hotkey -- returns an error
+
+The procfs interface does not support NVRAM polling control. So as to
+maintain maximum bug-to-bug compatibility, it does not report any masks,
+nor does it allow one to manipulate the hot key mask when the firmware
+does not support masks at all, even if NVRAM polling is in use.
+
+sysfs notes:
+
+ hotkey_bios_enabled:
+ DEPRECATED, WILL BE REMOVED SOON.
+
+ Returns 0.
+
+ hotkey_bios_mask:
+ DEPRECATED, DON'T USE, WILL BE REMOVED IN THE FUTURE.
+
+ Returns the hot keys mask when thinkpad-acpi was loaded.
+ Upon module unload, the hot keys mask will be restored
+ to this value. This is always 0x80c, because those are
+ the hotkeys that were supported by ancient firmware
+ without mask support.
+
+ hotkey_enable:
+ DEPRECATED, WILL BE REMOVED SOON.
+
+ 0: returns -EPERM
+ 1: does nothing
+
+ hotkey_mask:
+ bit mask to enable reporting (and depending on
+ the firmware, ACPI event generation) for each hot key
+ (see above). Returns the current status of the hot keys
+ mask, and allows one to modify it.
+
+ hotkey_all_mask:
+ bit mask that should enable event reporting for all
+ supported hot keys, when echoed to hotkey_mask above.
+ Unless you know which events need to be handled
+ passively (because the firmware *will* handle them
+ anyway), do *not* use hotkey_all_mask. Use
+ hotkey_recommended_mask, instead. You have been warned.
+
+ hotkey_recommended_mask:
+ bit mask that should enable event reporting for all
+ supported hot keys, except those which are always
+ handled by the firmware anyway. Echo it to
+ hotkey_mask above, to use. This is the default mask
+ used by the driver.
+
+ hotkey_source_mask:
+ bit mask that selects which hot keys will the driver
+ poll the NVRAM for. This is auto-detected by the driver
+ based on the capabilities reported by the ACPI firmware,
+ but it can be overridden at runtime.
+
+ Hot keys whose bits are set in hotkey_source_mask are
+ polled for in NVRAM, and reported as hotkey events if
+ enabled in hotkey_mask. Only a few hot keys are
+ available through CMOS NVRAM polling.
+
+ Warning: when in NVRAM mode, the volume up/down/mute
+ keys are synthesized according to changes in the mixer,
+ which uses a single volume up or volume down hotkey
+ press to unmute, as per the ThinkPad volume mixer user
+ interface. When in ACPI event mode, volume up/down/mute
+ events are reported by the firmware and can behave
+ differently (and that behaviour changes with firmware
+ version -- not just with firmware models -- as well as
+ OSI(Linux) state).
+
+ hotkey_poll_freq:
+ frequency in Hz for hot key polling. It must be between
+ 0 and 25 Hz. Polling is only carried out when strictly
+ needed.
+
+ Setting hotkey_poll_freq to zero disables polling, and
+ will cause hot key presses that require NVRAM polling
+ to never be reported.
+
+ Setting hotkey_poll_freq too low may cause repeated
+ pressings of the same hot key to be misreported as a
+ single key press, or to not even be detected at all.
+ The recommended polling frequency is 10Hz.
+
+ hotkey_radio_sw:
+ If the ThinkPad has a hardware radio switch, this
+ attribute will read 0 if the switch is in the "radios
+ disabled" position, and 1 if the switch is in the
+ "radios enabled" position.
+
+ This attribute has poll()/select() support.
+
+ hotkey_tablet_mode:
+ If the ThinkPad has tablet capabilities, this attribute
+ will read 0 if the ThinkPad is in normal mode, and
+ 1 if the ThinkPad is in tablet mode.
+
+ This attribute has poll()/select() support.
+
+ hotkey_report_mode:
+ Returns the state of the procfs ACPI event report mode
+ filter for hot keys. If it is set to 1 (the default),
+ all hot key presses are reported both through the input
+ layer and also as ACPI events through procfs (but not
+ through netlink). If it is set to 2, hot key presses
+ are reported only through the input layer.
+
+ This attribute is read-only in kernels 2.6.23 or later,
+ and read-write on earlier kernels.
+
+ May return -EPERM (write access locked out by module
+ parameter) or -EACCES (read-only).
+
+ wakeup_reason:
+ Set to 1 if the system is waking up because the user
+ requested a bay ejection. Set to 2 if the system is
+ waking up because the user requested the system to
+ undock. Set to zero for normal wake-ups or wake-ups
+ due to unknown reasons.
+
+ This attribute has poll()/select() support.
+
+ wakeup_hotunplug_complete:
+ Set to 1 if the system was waken up because of an
+ undock or bay ejection request, and that request
+ was successfully completed. At this point, it might
+ be useful to send the system back to sleep, at the
+ user's choice. Refer to HKEY events 0x4003 and
+ 0x3003, below.
+
+ This attribute has poll()/select() support.
+
+input layer notes:
+
+A Hot key is mapped to a single input layer EV_KEY event, possibly
+followed by an EV_MSC MSC_SCAN event that shall contain that key's scan
+code. An EV_SYN event will always be generated to mark the end of the
+event block.
+
+Do not use the EV_MSC MSC_SCAN events to process keys. They are to be
+used as a helper to remap keys, only. They are particularly useful when
+remapping KEY_UNKNOWN keys.
+
+The events are available in an input device, with the following id:
+
+ Bus: BUS_HOST
+ vendor: 0x1014 (PCI_VENDOR_ID_IBM) or
+ 0x17aa (PCI_VENDOR_ID_LENOVO)
+ product: 0x5054 ("TP")
+ version: 0x4101
+
+The version will have its LSB incremented if the keymap changes in a
+backwards-compatible way. The MSB shall always be 0x41 for this input
+device. If the MSB is not 0x41, do not use the device as described in
+this section, as it is either something else (e.g. another input device
+exported by a thinkpad driver, such as HDAPS) or its functionality has
+been changed in a non-backwards compatible way.
+
+Adding other event types for other functionalities shall be considered a
+backwards-compatible change for this input device.
+
+Thinkpad-acpi Hot Key event map (version 0x4101):
+
+ACPI Scan
+event code Key Notes
+
+0x1001 0x00 FN+F1 -
+
+0x1002 0x01 FN+F2 IBM: battery (rare)
+ Lenovo: Screen lock
+
+0x1003 0x02 FN+F3 Many IBM models always report
+ this hot key, even with hot keys
+ disabled or with Fn+F3 masked
+ off
+ IBM: screen lock, often turns
+ off the ThinkLight as side-effect
+ Lenovo: battery
+
+0x1004 0x03 FN+F4 Sleep button (ACPI sleep button
+ semantics, i.e. sleep-to-RAM).
+ It always generates some kind
+ of event, either the hot key
+ event or an ACPI sleep button
+ event. The firmware may
+ refuse to generate further FN+F4
+ key presses until a S3 or S4 ACPI
+ sleep cycle is performed or some
+ time passes.
+
+0x1005 0x04 FN+F5 Radio. Enables/disables
+ the internal Bluetooth hardware
+ and W-WAN card if left in control
+ of the firmware. Does not affect
+ the WLAN card.
+ Should be used to turn on/off all
+ radios (Bluetooth+W-WAN+WLAN),
+ really.
+
+0x1006 0x05 FN+F6 -
+
+0x1007 0x06 FN+F7 Video output cycle.
+ Do you feel lucky today?
+
+0x1008 0x07 FN+F8 IBM: toggle screen expand
+ Lenovo: configure UltraNav,
+ or toggle screen expand
+
+0x1009 0x08 FN+F9 -
+ .. .. ..
+0x100B 0x0A FN+F11 -
+
+0x100C 0x0B FN+F12 Sleep to disk. You are always
+ supposed to handle it yourself,
+ either through the ACPI event,
+ or through a hotkey event.
+ The firmware may refuse to
+ generate further FN+F12 key
+ press events until a S3 or S4
+ ACPI sleep cycle is performed,
+ or some time passes.
+
+0x100D 0x0C FN+BACKSPACE -
+0x100E 0x0D FN+INSERT -
+0x100F 0x0E FN+DELETE -
+
+0x1010 0x0F FN+HOME Brightness up. This key is
+ always handled by the firmware
+ in IBM ThinkPads, even when
+ unmasked. Just leave it alone.
+ For Lenovo ThinkPads with a new
+ BIOS, it has to be handled either
+ by the ACPI OSI, or by userspace.
+ The driver does the right thing,
+ never mess with this.
+0x1011 0x10 FN+END Brightness down. See brightness
+ up for details.
+
+0x1012 0x11 FN+PGUP ThinkLight toggle. This key is
+ always handled by the firmware,
+ even when unmasked.
+
+0x1013 0x12 FN+PGDOWN -
+
+0x1014 0x13 FN+SPACE Zoom key
+
+0x1015 0x14 VOLUME UP Internal mixer volume up. This
+ key is always handled by the
+ firmware, even when unmasked.
+ NOTE: Lenovo seems to be changing
+ this.
+0x1016 0x15 VOLUME DOWN Internal mixer volume up. This
+ key is always handled by the
+ firmware, even when unmasked.
+ NOTE: Lenovo seems to be changing
+ this.
+0x1017 0x16 MUTE Mute internal mixer. This
+ key is always handled by the
+ firmware, even when unmasked.
+
+0x1018 0x17 THINKPAD ThinkPad/Access IBM/Lenovo key
+
+0x1019 0x18 unknown
+.. .. ..
+0x1020 0x1F unknown
+
+The ThinkPad firmware does not allow one to differentiate when most hot
+keys are pressed or released (either that, or we don't know how to, yet).
+For these keys, the driver generates a set of events for a key press and
+immediately issues the same set of events for a key release. It is
+unknown by the driver if the ThinkPad firmware triggered these events on
+hot key press or release, but the firmware will do it for either one, not
+both.
+
+If a key is mapped to KEY_RESERVED, it generates no input events at all.
+If a key is mapped to KEY_UNKNOWN, it generates an input event that
+includes an scan code. If a key is mapped to anything else, it will
+generate input device EV_KEY events.
+
+In addition to the EV_KEY events, thinkpad-acpi may also issue EV_SW
+events for switches:
+
+SW_RFKILL_ALL T60 and later hardware rfkill rocker switch
+SW_TABLET_MODE Tablet ThinkPads HKEY events 0x5009 and 0x500A
+
+Non hotkey ACPI HKEY event map:
+-------------------------------
+
+Events that are not propagated by the driver, except for legacy
+compatibility purposes when hotkey_report_mode is set to 1:
+
+0x5001 Lid closed
+0x5002 Lid opened
+0x5009 Tablet swivel: switched to tablet mode
+0x500A Tablet swivel: switched to normal mode
+0x7000 Radio Switch may have changed state
+
+Events that are never propagated by the driver:
+
+0x2304 System is waking up from suspend to undock
+0x2305 System is waking up from suspend to eject bay
+0x2404 System is waking up from hibernation to undock
+0x2405 System is waking up from hibernation to eject bay
+0x5010 Brightness level changed/control event
+0x6000 KEYBOARD: Numlock key pressed
+0x6005 KEYBOARD: Fn key pressed (TO BE VERIFIED)
+
+Events that are propagated by the driver to userspace:
+
+0x2313 ALARM: System is waking up from suspend because
+ the battery is nearly empty
+0x2413 ALARM: System is waking up from hibernation because
+ the battery is nearly empty
+0x3003 Bay ejection (see 0x2x05) complete, can sleep again
+0x3006 Bay hotplug request (hint to power up SATA link when
+ the optical drive tray is ejected)
+0x4003 Undocked (see 0x2x04), can sleep again
+0x4010 Docked into hotplug port replicator (non-ACPI dock)
+0x4011 Undocked from hotplug port replicator (non-ACPI dock)
+0x500B Tablet pen inserted into its storage bay
+0x500C Tablet pen removed from its storage bay
+0x6011 ALARM: battery is too hot
+0x6012 ALARM: battery is extremely hot
+0x6021 ALARM: a sensor is too hot
+0x6022 ALARM: a sensor is extremely hot
+0x6030 System thermal table changed
+0x6040 Nvidia Optimus/AC adapter related (TO BE VERIFIED)
+
+Battery nearly empty alarms are a last resort attempt to get the
+operating system to hibernate or shutdown cleanly (0x2313), or shutdown
+cleanly (0x2413) before power is lost. They must be acted upon, as the
+wake up caused by the firmware will have negated most safety nets...
+
+When any of the "too hot" alarms happen, according to Lenovo the user
+should suspend or hibernate the laptop (and in the case of battery
+alarms, unplug the AC adapter) to let it cool down. These alarms do
+signal that something is wrong, they should never happen on normal
+operating conditions.
+
+The "extremely hot" alarms are emergencies. According to Lenovo, the
+operating system is to force either an immediate suspend or hibernate
+cycle, or a system shutdown. Obviously, something is very wrong if this
+happens.
+
+Compatibility notes:
+
+ibm-acpi and thinkpad-acpi 0.15 (mainline kernels before 2.6.23) never
+supported the input layer, and sent events over the procfs ACPI event
+interface.
+
+To avoid sending duplicate events over the input layer and the ACPI
+event interface, thinkpad-acpi 0.16 implements a module parameter
+(hotkey_report_mode), and also a sysfs device attribute with the same
+name.
+
+Make no mistake here: userspace is expected to switch to using the input
+layer interface of thinkpad-acpi, together with the ACPI netlink event
+interface in kernels 2.6.23 and later, or with the ACPI procfs event
+interface in kernels 2.6.22 and earlier.
+
+If no hotkey_report_mode module parameter is specified (or it is set to
+zero), the driver defaults to mode 1 (see below), and on kernels 2.6.22
+and earlier, also allows one to change the hotkey_report_mode through
+sysfs. In kernels 2.6.23 and later, where the netlink ACPI event
+interface is available, hotkey_report_mode cannot be changed through
+sysfs (it is read-only).
+
+If the hotkey_report_mode module parameter is set to 1 or 2, it cannot
+be changed later through sysfs (any writes will return -EPERM to signal
+that hotkey_report_mode was locked. On 2.6.23 and later, where
+hotkey_report_mode cannot be changed at all, writes will return -EACCES).
+
+hotkey_report_mode set to 1 makes the driver export through the procfs
+ACPI event interface all hot key presses (which are *also* sent to the
+input layer). This is a legacy compatibility behaviour, and it is also
+the default mode of operation for the driver.
+
+hotkey_report_mode set to 2 makes the driver filter out the hot key
+presses from the procfs ACPI event interface, so these events will only
+be sent through the input layer. Userspace that has been updated to use
+the thinkpad-acpi input layer interface should set hotkey_report_mode to
+2.
+
+Hot key press events are never sent to the ACPI netlink event interface.
+Really up-to-date userspace under kernel 2.6.23 and later is to use the
+netlink interface and the input layer interface, and don't bother at all
+with hotkey_report_mode.
+
+
+Brightness hotkey notes:
+
+Don't mess with the brightness hotkeys in a Thinkpad. If you want
+notifications for OSD, use the sysfs backlight class event support.
+
+The driver will issue KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN events
+automatically for the cases were userspace has to do something to
+implement brightness changes. When you override these events, you will
+either fail to handle properly the ThinkPads that require explicit
+action to change backlight brightness, or the ThinkPads that require
+that no action be taken to work properly.
+
+
+Bluetooth
+---------
+
+procfs: /proc/acpi/ibm/bluetooth
+sysfs device attribute: bluetooth_enable (deprecated)
+sysfs rfkill class: switch "tpacpi_bluetooth_sw"
+
+This feature shows the presence and current state of a ThinkPad
+Bluetooth device in the internal ThinkPad CDC slot.
+
+If the ThinkPad supports it, the Bluetooth state is stored in NVRAM,
+so it is kept across reboots and power-off.
+
+Procfs notes:
+
+If Bluetooth is installed, the following commands can be used:
+
+ echo enable > /proc/acpi/ibm/bluetooth
+ echo disable > /proc/acpi/ibm/bluetooth
+
+Sysfs notes:
+
+ If the Bluetooth CDC card is installed, it can be enabled /
+ disabled through the "bluetooth_enable" thinkpad-acpi device
+ attribute, and its current status can also be queried.
+
+ enable:
+ 0: disables Bluetooth / Bluetooth is disabled
+ 1: enables Bluetooth / Bluetooth is enabled.
+
+ Note: this interface has been superseded by the generic rfkill
+ class. It has been deprecated, and it will be removed in year
+ 2010.
+
+ rfkill controller switch "tpacpi_bluetooth_sw": refer to
+ Documentation/rfkill.txt for details.
+
+
+Video output control -- /proc/acpi/ibm/video
+--------------------------------------------
+
+This feature allows control over the devices used for video output -
+LCD, CRT or DVI (if available). The following commands are available:
+
+ echo lcd_enable > /proc/acpi/ibm/video
+ echo lcd_disable > /proc/acpi/ibm/video
+ echo crt_enable > /proc/acpi/ibm/video
+ echo crt_disable > /proc/acpi/ibm/video
+ echo dvi_enable > /proc/acpi/ibm/video
+ echo dvi_disable > /proc/acpi/ibm/video
+ echo auto_enable > /proc/acpi/ibm/video
+ echo auto_disable > /proc/acpi/ibm/video
+ echo expand_toggle > /proc/acpi/ibm/video
+ echo video_switch > /proc/acpi/ibm/video
+
+NOTE: Access to this feature is restricted to processes owning the
+CAP_SYS_ADMIN capability for safety reasons, as it can interact badly
+enough with some versions of X.org to crash it.
+
+Each video output device can be enabled or disabled individually.
+Reading /proc/acpi/ibm/video shows the status of each device.
+
+Automatic video switching can be enabled or disabled. When automatic
+video switching is enabled, certain events (e.g. opening the lid,
+docking or undocking) cause the video output device to change
+automatically. While this can be useful, it also causes flickering
+and, on the X40, video corruption. By disabling automatic switching,
+the flickering or video corruption can be avoided.
+
+The video_switch command cycles through the available video outputs
+(it simulates the behavior of Fn-F7).
+
+Video expansion can be toggled through this feature. This controls
+whether the display is expanded to fill the entire LCD screen when a
+mode with less than full resolution is used. Note that the current
+video expansion status cannot be determined through this feature.
+
+Note that on many models (particularly those using Radeon graphics
+chips) the X driver configures the video card in a way which prevents
+Fn-F7 from working. This also disables the video output switching
+features of this driver, as it uses the same ACPI methods as
+Fn-F7. Video switching on the console should still work.
+
+UPDATE: refer to https://bugs.freedesktop.org/show_bug.cgi?id=2000
+
+
+ThinkLight control
+------------------
+
+procfs: /proc/acpi/ibm/light
+sysfs attributes: as per LED class, for the "tpacpi::thinklight" LED
+
+procfs notes:
+
+The ThinkLight status can be read and set through the procfs interface. A
+few models which do not make the status available will show the ThinkLight
+status as "unknown". The available commands are:
+
+ echo on > /proc/acpi/ibm/light
+ echo off > /proc/acpi/ibm/light
+
+sysfs notes:
+
+The ThinkLight sysfs interface is documented by the LED class
+documentation, in Documentation/leds/leds-class.txt. The ThinkLight LED name
+is "tpacpi::thinklight".
+
+Due to limitations in the sysfs LED class, if the status of the ThinkLight
+cannot be read or if it is unknown, thinkpad-acpi will report it as "off".
+It is impossible to know if the status returned through sysfs is valid.
+
+
+CMOS/UCMS control
+-----------------
+
+procfs: /proc/acpi/ibm/cmos
+sysfs device attribute: cmos_command
+
+This feature is mostly used internally by the ACPI firmware to keep the legacy
+CMOS NVRAM bits in sync with the current machine state, and to record this
+state so that the ThinkPad will retain such settings across reboots.
+
+Some of these commands actually perform actions in some ThinkPad models, but
+this is expected to disappear more and more in newer models. As an example, in
+a T43 and in a X40, commands 12 and 13 still control the ThinkLight state for
+real, but commands 0 to 2 don't control the mixer anymore (they have been
+phased out) and just update the NVRAM.
+
+The range of valid cmos command numbers is 0 to 21, but not all have an
+effect and the behavior varies from model to model. Here is the behavior
+on the X40 (tpb is the ThinkPad Buttons utility):
+
+ 0 - Related to "Volume down" key press
+ 1 - Related to "Volume up" key press
+ 2 - Related to "Mute on" key press
+ 3 - Related to "Access IBM" key press
+ 4 - Related to "LCD brightness up" key press
+ 5 - Related to "LCD brightness down" key press
+ 11 - Related to "toggle screen expansion" key press/function
+ 12 - Related to "ThinkLight on"
+ 13 - Related to "ThinkLight off"
+ 14 - Related to "ThinkLight" key press (toggle ThinkLight)
+
+The cmos command interface is prone to firmware split-brain problems, as
+in newer ThinkPads it is just a compatibility layer. Do not use it, it is
+exported just as a debug tool.
+
+
+LED control
+-----------
+
+procfs: /proc/acpi/ibm/led
+sysfs attributes: as per LED class, see below for names
+
+Some of the LED indicators can be controlled through this feature. On
+some older ThinkPad models, it is possible to query the status of the
+LED indicators as well. Newer ThinkPads cannot query the real status
+of the LED indicators.
+
+Because misuse of the LEDs could induce an unaware user to perform
+dangerous actions (like undocking or ejecting a bay device while the
+buses are still active), or mask an important alarm (such as a nearly
+empty battery, or a broken battery), access to most LEDs is
+restricted.
+
+Unrestricted access to all LEDs requires that thinkpad-acpi be
+compiled with the CONFIG_THINKPAD_ACPI_UNSAFE_LEDS option enabled.
+Distributions must never enable this option. Individual users that
+are aware of the consequences are welcome to enabling it.
+
+procfs notes:
+
+The available commands are:
+
+ echo '<LED number> on' >/proc/acpi/ibm/led
+ echo '<LED number> off' >/proc/acpi/ibm/led
+ echo '<LED number> blink' >/proc/acpi/ibm/led
+
+The <LED number> range is 0 to 15. The set of LEDs that can be
+controlled varies from model to model. Here is the common ThinkPad
+mapping:
+
+ 0 - power
+ 1 - battery (orange)
+ 2 - battery (green)
+ 3 - UltraBase/dock
+ 4 - UltraBay
+ 5 - UltraBase battery slot
+ 6 - (unknown)
+ 7 - standby
+ 8 - dock status 1
+ 9 - dock status 2
+ 10, 11 - (unknown)
+ 12 - thinkvantage
+ 13, 14, 15 - (unknown)
+
+All of the above can be turned on and off and can be made to blink.
+
+sysfs notes:
+
+The ThinkPad LED sysfs interface is described in detail by the LED class
+documentation, in Documentation/leds/leds-class.txt.
+
+The LEDs are named (in LED ID order, from 0 to 12):
+"tpacpi::power", "tpacpi:orange:batt", "tpacpi:green:batt",
+"tpacpi::dock_active", "tpacpi::bay_active", "tpacpi::dock_batt",
+"tpacpi::unknown_led", "tpacpi::standby", "tpacpi::dock_status1",
+"tpacpi::dock_status2", "tpacpi::unknown_led2", "tpacpi::unknown_led3",
+"tpacpi::thinkvantage".
+
+Due to limitations in the sysfs LED class, if the status of the LED
+indicators cannot be read due to an error, thinkpad-acpi will report it as
+a brightness of zero (same as LED off).
+
+If the thinkpad firmware doesn't support reading the current status,
+trying to read the current LED brightness will just return whatever
+brightness was last written to that attribute.
+
+These LEDs can blink using hardware acceleration. To request that a
+ThinkPad indicator LED should blink in hardware accelerated mode, use the
+"timer" trigger, and leave the delay_on and delay_off parameters set to
+zero (to request hardware acceleration autodetection).
+
+LEDs that are known not to exist in a given ThinkPad model are not
+made available through the sysfs interface. If you have a dock and you
+notice there are LEDs listed for your ThinkPad that do not exist (and
+are not in the dock), or if you notice that there are missing LEDs,
+a report to ibm-acpi-devel@lists.sourceforge.net is appreciated.
+
+
+ACPI sounds -- /proc/acpi/ibm/beep
+----------------------------------
+
+The BEEP method is used internally by the ACPI firmware to provide
+audible alerts in various situations. This feature allows the same
+sounds to be triggered manually.
+
+The commands are non-negative integer numbers:
+
+ echo <number> >/proc/acpi/ibm/beep
+
+The valid <number> range is 0 to 17. Not all numbers trigger sounds
+and the sounds vary from model to model. Here is the behavior on the
+X40:
+
+ 0 - stop a sound in progress (but use 17 to stop 16)
+ 2 - two beeps, pause, third beep ("low battery")
+ 3 - single beep
+ 4 - high, followed by low-pitched beep ("unable")
+ 5 - single beep
+ 6 - very high, followed by high-pitched beep ("AC/DC")
+ 7 - high-pitched beep
+ 9 - three short beeps
+ 10 - very long beep
+ 12 - low-pitched beep
+ 15 - three high-pitched beeps repeating constantly, stop with 0
+ 16 - one medium-pitched beep repeating constantly, stop with 17
+ 17 - stop 16
+
+
+Temperature sensors
+-------------------
+
+procfs: /proc/acpi/ibm/thermal
+sysfs device attributes: (hwmon "thinkpad") temp*_input
+
+Most ThinkPads include six or more separate temperature sensors but only
+expose the CPU temperature through the standard ACPI methods. This
+feature shows readings from up to eight different sensors on older
+ThinkPads, and up to sixteen different sensors on newer ThinkPads.
+
+For example, on the X40, a typical output may be:
+temperatures: 42 42 45 41 36 -128 33 -128
+
+On the T43/p, a typical output may be:
+temperatures: 48 48 36 52 38 -128 31 -128 48 52 48 -128 -128 -128 -128 -128
+
+The mapping of thermal sensors to physical locations varies depending on
+system-board model (and thus, on ThinkPad model).
+
+http://thinkwiki.org/wiki/Thermal_Sensors is a public wiki page that
+tries to track down these locations for various models.
+
+Most (newer?) models seem to follow this pattern:
+
+1: CPU
+2: (depends on model)
+3: (depends on model)
+4: GPU
+5: Main battery: main sensor
+6: Bay battery: main sensor
+7: Main battery: secondary sensor
+8: Bay battery: secondary sensor
+9-15: (depends on model)
+
+For the R51 (source: Thomas Gruber):
+2: Mini-PCI
+3: Internal HDD
+
+For the T43, T43/p (source: Shmidoax/Thinkwiki.org)
+http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_T43.2C_T43p
+2: System board, left side (near PCMCIA slot), reported as HDAPS temp
+3: PCMCIA slot
+9: MCH (northbridge) to DRAM Bus
+10: Clock-generator, mini-pci card and ICH (southbridge), under Mini-PCI
+ card, under touchpad
+11: Power regulator, underside of system board, below F2 key
+
+The A31 has a very atypical layout for the thermal sensors
+(source: Milos Popovic, http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_A31)
+1: CPU
+2: Main Battery: main sensor
+3: Power Converter
+4: Bay Battery: main sensor
+5: MCH (northbridge)
+6: PCMCIA/ambient
+7: Main Battery: secondary sensor
+8: Bay Battery: secondary sensor
+
+
+Procfs notes:
+ Readings from sensors that are not available return -128.
+ No commands can be written to this file.
+
+Sysfs notes:
+ Sensors that are not available return the ENXIO error. This
+ status may change at runtime, as there are hotplug thermal
+ sensors, like those inside the batteries and docks.
+
+ thinkpad-acpi thermal sensors are reported through the hwmon
+ subsystem, and follow all of the hwmon guidelines at
+ Documentation/hwmon.
+
+EXPERIMENTAL: Embedded controller register dump
+-----------------------------------------------
+
+This feature is not included in the thinkpad driver anymore.
+Instead the EC can be accessed through /sys/kernel/debug/ec with
+a userspace tool which can be found here:
+ftp://ftp.suse.com/pub/people/trenn/sources/ec
+
+Use it to determine the register holding the fan
+speed on some models. To do that, do the following:
+ - make sure the battery is fully charged
+ - make sure the fan is running
+ - use above mentioned tool to read out the EC
+
+Often fan and temperature values vary between
+readings. Since temperatures don't change vary fast, you can take
+several quick dumps to eliminate them.
+
+You can use a similar method to figure out the meaning of other
+embedded controller registers - e.g. make sure nothing else changes
+except the charging or discharging battery to determine which
+registers contain the current battery capacity, etc. If you experiment
+with this, do send me your results (including some complete dumps with
+a description of the conditions when they were taken.)
+
+
+LCD brightness control
+----------------------
+
+procfs: /proc/acpi/ibm/brightness
+sysfs backlight device "thinkpad_screen"
+
+This feature allows software control of the LCD brightness on ThinkPad
+models which don't have a hardware brightness slider.
+
+It has some limitations: the LCD backlight cannot be actually turned
+on or off by this interface, it just controls the backlight brightness
+level.
+
+On IBM (and some of the earlier Lenovo) ThinkPads, the backlight control
+has eight brightness levels, ranging from 0 to 7. Some of the levels
+may not be distinct. Later Lenovo models that implement the ACPI
+display backlight brightness control methods have 16 levels, ranging
+from 0 to 15.
+
+For IBM ThinkPads, there are two interfaces to the firmware for direct
+brightness control, EC and UCMS (or CMOS). To select which one should be
+used, use the brightness_mode module parameter: brightness_mode=1 selects
+EC mode, brightness_mode=2 selects UCMS mode, brightness_mode=3 selects EC
+mode with NVRAM backing (so that brightness changes are remembered across
+shutdown/reboot).
+
+The driver tries to select which interface to use from a table of
+defaults for each ThinkPad model. If it makes a wrong choice, please
+report this as a bug, so that we can fix it.
+
+Lenovo ThinkPads only support brightness_mode=2 (UCMS).
+
+When display backlight brightness controls are available through the
+standard ACPI interface, it is best to use it instead of this direct
+ThinkPad-specific interface. The driver will disable its native
+backlight brightness control interface if it detects that the standard
+ACPI interface is available in the ThinkPad.
+
+If you want to use the thinkpad-acpi backlight brightness control
+instead of the generic ACPI video backlight brightness control for some
+reason, you should use the acpi_backlight=vendor kernel parameter.
+
+The brightness_enable module parameter can be used to control whether
+the LCD brightness control feature will be enabled when available.
+brightness_enable=0 forces it to be disabled. brightness_enable=1
+forces it to be enabled when available, even if the standard ACPI
+interface is also available.
+
+Procfs notes:
+
+ The available commands are:
+
+ echo up >/proc/acpi/ibm/brightness
+ echo down >/proc/acpi/ibm/brightness
+ echo 'level <level>' >/proc/acpi/ibm/brightness
+
+Sysfs notes:
+
+The interface is implemented through the backlight sysfs class, which is
+poorly documented at this time.
+
+Locate the thinkpad_screen device under /sys/class/backlight, and inside
+it there will be the following attributes:
+
+ max_brightness:
+ Reads the maximum brightness the hardware can be set to.
+ The minimum is always zero.
+
+ actual_brightness:
+ Reads what brightness the screen is set to at this instant.
+
+ brightness:
+ Writes request the driver to change brightness to the
+ given value. Reads will tell you what brightness the
+ driver is trying to set the display to when "power" is set
+ to zero and the display has not been dimmed by a kernel
+ power management event.
+
+ power:
+ power management mode, where 0 is "display on", and 1 to 3
+ will dim the display backlight to brightness level 0
+ because thinkpad-acpi cannot really turn the backlight
+ off. Kernel power management events can temporarily
+ increase the current power management level, i.e. they can
+ dim the display.
+
+
+WARNING:
+
+ Whatever you do, do NOT ever call thinkpad-acpi backlight-level change
+ interface and the ACPI-based backlight level change interface
+ (available on newer BIOSes, and driven by the Linux ACPI video driver)
+ at the same time. The two will interact in bad ways, do funny things,
+ and maybe reduce the life of the backlight lamps by needlessly kicking
+ its level up and down at every change.
+
+
+Volume control (Console Audio control)
+--------------------------------------
+
+procfs: /proc/acpi/ibm/volume
+ALSA: "ThinkPad Console Audio Control", default ID: "ThinkPadEC"
+
+NOTE: by default, the volume control interface operates in read-only
+mode, as it is supposed to be used for on-screen-display purposes.
+The read/write mode can be enabled through the use of the
+"volume_control=1" module parameter.
+
+NOTE: distros are urged to not enable volume_control by default, this
+should be done by the local admin only. The ThinkPad UI is for the
+console audio control to be done through the volume keys only, and for
+the desktop environment to just provide on-screen-display feedback.
+Software volume control should be done only in the main AC97/HDA
+mixer.
+
+
+About the ThinkPad Console Audio control:
+
+ThinkPads have a built-in amplifier and muting circuit that drives the
+console headphone and speakers. This circuit is after the main AC97
+or HDA mixer in the audio path, and under exclusive control of the
+firmware.
+
+ThinkPads have three special hotkeys to interact with the console
+audio control: volume up, volume down and mute.
+
+It is worth noting that the normal way the mute function works (on
+ThinkPads that do not have a "mute LED") is:
+
+1. Press mute to mute. It will *always* mute, you can press it as
+ many times as you want, and the sound will remain mute.
+
+2. Press either volume key to unmute the ThinkPad (it will _not_
+ change the volume, it will just unmute).
+
+This is a very superior design when compared to the cheap software-only
+mute-toggle solution found on normal consumer laptops: you can be
+absolutely sure the ThinkPad will not make noise if you press the mute
+button, no matter the previous state.
+
+The IBM ThinkPads, and the earlier Lenovo ThinkPads have variable-gain
+amplifiers driving the speakers and headphone output, and the firmware
+also handles volume control for the headphone and speakers on these
+ThinkPads without any help from the operating system (this volume
+control stage exists after the main AC97 or HDA mixer in the audio
+path).
+
+The newer Lenovo models only have firmware mute control, and depend on
+the main HDA mixer to do volume control (which is done by the operating
+system). In this case, the volume keys are filtered out for unmute
+key press (there are some firmware bugs in this area) and delivered as
+normal key presses to the operating system (thinkpad-acpi is not
+involved).
+
+
+The ThinkPad-ACPI volume control:
+
+The preferred way to interact with the Console Audio control is the
+ALSA interface.
+
+The legacy procfs interface allows one to read the current state,
+and if volume control is enabled, accepts the following commands:
+
+ echo up >/proc/acpi/ibm/volume
+ echo down >/proc/acpi/ibm/volume
+ echo mute >/proc/acpi/ibm/volume
+ echo unmute >/proc/acpi/ibm/volume
+ echo 'level <level>' >/proc/acpi/ibm/volume
+
+The <level> number range is 0 to 14 although not all of them may be
+distinct. To unmute the volume after the mute command, use either the
+up or down command (the level command will not unmute the volume), or
+the unmute command.
+
+You can use the volume_capabilities parameter to tell the driver
+whether your thinkpad has volume control or mute-only control:
+volume_capabilities=1 for mixers with mute and volume control,
+volume_capabilities=2 for mixers with only mute control.
+
+If the driver misdetects the capabilities for your ThinkPad model,
+please report this to ibm-acpi-devel@lists.sourceforge.net, so that we
+can update the driver.
+
+There are two strategies for volume control. To select which one
+should be used, use the volume_mode module parameter: volume_mode=1
+selects EC mode, and volume_mode=3 selects EC mode with NVRAM backing
+(so that volume/mute changes are remembered across shutdown/reboot).
+
+The driver will operate in volume_mode=3 by default. If that does not
+work well on your ThinkPad model, please report this to
+ibm-acpi-devel@lists.sourceforge.net.
+
+The driver supports the standard ALSA module parameters. If the ALSA
+mixer is disabled, the driver will disable all volume functionality.
+
+
+Fan control and monitoring: fan speed, fan enable/disable
+---------------------------------------------------------
+
+procfs: /proc/acpi/ibm/fan
+sysfs device attributes: (hwmon "thinkpad") fan1_input, pwm1,
+ pwm1_enable, fan2_input
+sysfs hwmon driver attributes: fan_watchdog
+
+NOTE NOTE NOTE: fan control operations are disabled by default for
+safety reasons. To enable them, the module parameter "fan_control=1"
+must be given to thinkpad-acpi.
+
+This feature attempts to show the current fan speed, control mode and
+other fan data that might be available. The speed is read directly
+from the hardware registers of the embedded controller. This is known
+to work on later R, T, X and Z series ThinkPads but may show a bogus
+value on other models.
+
+Some Lenovo ThinkPads support a secondary fan. This fan cannot be
+controlled separately, it shares the main fan control.
+
+Fan levels:
+
+Most ThinkPad fans work in "levels" at the firmware interface. Level 0
+stops the fan. The higher the level, the higher the fan speed, although
+adjacent levels often map to the same fan speed. 7 is the highest
+level, where the fan reaches the maximum recommended speed.
+
+Level "auto" means the EC changes the fan level according to some
+internal algorithm, usually based on readings from the thermal sensors.
+
+There is also a "full-speed" level, also known as "disengaged" level.
+In this level, the EC disables the speed-locked closed-loop fan control,
+and drives the fan as fast as it can go, which might exceed hardware
+limits, so use this level with caution.
+
+The fan usually ramps up or down slowly from one speed to another, and
+it is normal for the EC to take several seconds to react to fan
+commands. The full-speed level may take up to two minutes to ramp up to
+maximum speed, and in some ThinkPads, the tachometer readings go stale
+while the EC is transitioning to the full-speed level.
+
+WARNING WARNING WARNING: do not leave the fan disabled unless you are
+monitoring all of the temperature sensor readings and you are ready to
+enable it if necessary to avoid overheating.
+
+An enabled fan in level "auto" may stop spinning if the EC decides the
+ThinkPad is cool enough and doesn't need the extra airflow. This is
+normal, and the EC will spin the fan up if the various thermal readings
+rise too much.
+
+On the X40, this seems to depend on the CPU and HDD temperatures.
+Specifically, the fan is turned on when either the CPU temperature
+climbs to 56 degrees or the HDD temperature climbs to 46 degrees. The
+fan is turned off when the CPU temperature drops to 49 degrees and the
+HDD temperature drops to 41 degrees. These thresholds cannot
+currently be controlled.
+
+The ThinkPad's ACPI DSDT code will reprogram the fan on its own when
+certain conditions are met. It will override any fan programming done
+through thinkpad-acpi.
+
+The thinkpad-acpi kernel driver can be programmed to revert the fan
+level to a safe setting if userspace does not issue one of the procfs
+fan commands: "enable", "disable", "level" or "watchdog", or if there
+are no writes to pwm1_enable (or to pwm1 *if and only if* pwm1_enable is
+set to 1, manual mode) within a configurable amount of time of up to
+120 seconds. This functionality is called fan safety watchdog.
+
+Note that the watchdog timer stops after it enables the fan. It will be
+rearmed again automatically (using the same interval) when one of the
+above mentioned fan commands is received. The fan watchdog is,
+therefore, not suitable to protect against fan mode changes made through
+means other than the "enable", "disable", and "level" procfs fan
+commands, or the hwmon fan control sysfs interface.
+
+Procfs notes:
+
+The fan may be enabled or disabled with the following commands:
+
+ echo enable >/proc/acpi/ibm/fan
+ echo disable >/proc/acpi/ibm/fan
+
+Placing a fan on level 0 is the same as disabling it. Enabling a fan
+will try to place it in a safe level if it is too slow or disabled.
+
+The fan level can be controlled with the command:
+
+ echo 'level <level>' > /proc/acpi/ibm/fan
+
+Where <level> is an integer from 0 to 7, or one of the words "auto" or
+"full-speed" (without the quotes). Not all ThinkPads support the "auto"
+and "full-speed" levels. The driver accepts "disengaged" as an alias for
+"full-speed", and reports it as "disengaged" for backwards
+compatibility.
+
+On the X31 and X40 (and ONLY on those models), the fan speed can be
+controlled to a certain degree. Once the fan is running, it can be
+forced to run faster or slower with the following command:
+
+ echo 'speed <speed>' > /proc/acpi/ibm/fan
+
+The sustainable range of fan speeds on the X40 appears to be from about
+3700 to about 7350. Values outside this range either do not have any
+effect or the fan speed eventually settles somewhere in that range. The
+fan cannot be stopped or started with this command. This functionality
+is incomplete, and not available through the sysfs interface.
+
+To program the safety watchdog, use the "watchdog" command.
+
+ echo 'watchdog <interval in seconds>' > /proc/acpi/ibm/fan
+
+If you want to disable the watchdog, use 0 as the interval.
+
+Sysfs notes:
+
+The sysfs interface follows the hwmon subsystem guidelines for the most
+part, and the exception is the fan safety watchdog.
+
+Writes to any of the sysfs attributes may return the EINVAL error if
+that operation is not supported in a given ThinkPad or if the parameter
+is out-of-bounds, and EPERM if it is forbidden. They may also return
+EINTR (interrupted system call), and EIO (I/O error while trying to talk
+to the firmware).
+
+Features not yet implemented by the driver return ENOSYS.
+
+hwmon device attribute pwm1_enable:
+ 0: PWM offline (fan is set to full-speed mode)
+ 1: Manual PWM control (use pwm1 to set fan level)
+ 2: Hardware PWM control (EC "auto" mode)
+ 3: reserved (Software PWM control, not implemented yet)
+
+ Modes 0 and 2 are not supported by all ThinkPads, and the
+ driver is not always able to detect this. If it does know a
+ mode is unsupported, it will return -EINVAL.
+
+hwmon device attribute pwm1:
+ Fan level, scaled from the firmware values of 0-7 to the hwmon
+ scale of 0-255. 0 means fan stopped, 255 means highest normal
+ speed (level 7).
+
+ This attribute only commands the fan if pmw1_enable is set to 1
+ (manual PWM control).
+
+hwmon device attribute fan1_input:
+ Fan tachometer reading, in RPM. May go stale on certain
+ ThinkPads while the EC transitions the PWM to offline mode,
+ which can take up to two minutes. May return rubbish on older
+ ThinkPads.
+
+hwmon device attribute fan2_input:
+ Fan tachometer reading, in RPM, for the secondary fan.
+ Available only on some ThinkPads. If the secondary fan is
+ not installed, will always read 0.
+
+hwmon driver attribute fan_watchdog:
+ Fan safety watchdog timer interval, in seconds. Minimum is
+ 1 second, maximum is 120 seconds. 0 disables the watchdog.
+
+To stop the fan: set pwm1 to zero, and pwm1_enable to 1.
+
+To start the fan in a safe mode: set pwm1_enable to 2. If that fails
+with EINVAL, try to set pwm1_enable to 1 and pwm1 to at least 128 (255
+would be the safest choice, though).
+
+
+WAN
+---
+
+procfs: /proc/acpi/ibm/wan
+sysfs device attribute: wwan_enable (deprecated)
+sysfs rfkill class: switch "tpacpi_wwan_sw"
+
+This feature shows the presence and current state of the built-in
+Wireless WAN device.
+
+If the ThinkPad supports it, the WWAN state is stored in NVRAM,
+so it is kept across reboots and power-off.
+
+It was tested on a Lenovo ThinkPad X60. It should probably work on other
+ThinkPad models which come with this module installed.
+
+Procfs notes:
+
+If the W-WAN card is installed, the following commands can be used:
+
+ echo enable > /proc/acpi/ibm/wan
+ echo disable > /proc/acpi/ibm/wan
+
+Sysfs notes:
+
+ If the W-WAN card is installed, it can be enabled /
+ disabled through the "wwan_enable" thinkpad-acpi device
+ attribute, and its current status can also be queried.
+
+ enable:
+ 0: disables WWAN card / WWAN card is disabled
+ 1: enables WWAN card / WWAN card is enabled.
+
+ Note: this interface has been superseded by the generic rfkill
+ class. It has been deprecated, and it will be removed in year
+ 2010.
+
+ rfkill controller switch "tpacpi_wwan_sw": refer to
+ Documentation/rfkill.txt for details.
+
+
+EXPERIMENTAL: UWB
+-----------------
+
+This feature is considered EXPERIMENTAL because it has not been extensively
+tested and validated in various ThinkPad models yet. The feature may not
+work as expected. USE WITH CAUTION! To use this feature, you need to supply
+the experimental=1 parameter when loading the module.
+
+sysfs rfkill class: switch "tpacpi_uwb_sw"
+
+This feature exports an rfkill controller for the UWB device, if one is
+present and enabled in the BIOS.
+
+Sysfs notes:
+
+ rfkill controller switch "tpacpi_uwb_sw": refer to
+ Documentation/rfkill.txt for details.
+
+
+Multiple Commands, Module Parameters
+------------------------------------
+
+Multiple commands can be written to the proc files in one shot by
+separating them with commas, for example:
+
+ echo enable,0xffff > /proc/acpi/ibm/hotkey
+ echo lcd_disable,crt_enable > /proc/acpi/ibm/video
+
+Commands can also be specified when loading the thinkpad-acpi module,
+for example:
+
+ modprobe thinkpad_acpi hotkey=enable,0xffff video=auto_disable
+
+
+Enabling debugging output
+-------------------------
+
+The module takes a debug parameter which can be used to selectively
+enable various classes of debugging output, for example:
+
+ modprobe thinkpad_acpi debug=0xffff
+
+will enable all debugging output classes. It takes a bitmask, so
+to enable more than one output class, just add their values.
+
+ Debug bitmask Description
+ 0x8000 Disclose PID of userspace programs
+ accessing some functions of the driver
+ 0x0001 Initialization and probing
+ 0x0002 Removal
+ 0x0004 RF Transmitter control (RFKILL)
+ (bluetooth, WWAN, UWB...)
+ 0x0008 HKEY event interface, hotkeys
+ 0x0010 Fan control
+ 0x0020 Backlight brightness
+ 0x0040 Audio mixer/volume control
+
+There is also a kernel build option to enable more debugging
+information, which may be necessary to debug driver problems.
+
+The level of debugging information output by the driver can be changed
+at runtime through sysfs, using the driver attribute debug_level. The
+attribute takes the same bitmask as the debug module parameter above.
+
+
+Force loading of module
+-----------------------
+
+If thinkpad-acpi refuses to detect your ThinkPad, you can try to specify
+the module parameter force_load=1. Regardless of whether this works or
+not, please contact ibm-acpi-devel@lists.sourceforge.net with a report.
+
+
+Sysfs interface changelog:
+
+0x000100: Initial sysfs support, as a single platform driver and
+ device.
+0x000200: Hot key support for 32 hot keys, and radio slider switch
+ support.
+0x010000: Hot keys are now handled by default over the input
+ layer, the radio switch generates input event EV_RADIO,
+ and the driver enables hot key handling by default in
+ the firmware.
+
+0x020000: ABI fix: added a separate hwmon platform device and
+ driver, which must be located by name (thinkpad)
+ and the hwmon class for libsensors4 (lm-sensors 3)
+ compatibility. Moved all hwmon attributes to this
+ new platform device.
+
+0x020100: Marker for thinkpad-acpi with hot key NVRAM polling
+ support. If you must, use it to know you should not
+ start a userspace NVRAM poller (allows to detect when
+ NVRAM is compiled out by the user because it is
+ unneeded/undesired in the first place).
+0x020101: Marker for thinkpad-acpi with hot key NVRAM polling
+ and proper hotkey_mask semantics (version 8 of the
+ NVRAM polling patch). Some development snapshots of
+ 0.18 had an earlier version that did strange things
+ to hotkey_mask.
+
+0x020200: Add poll()/select() support to the following attributes:
+ hotkey_radio_sw, wakeup_hotunplug_complete, wakeup_reason
+
+0x020300: hotkey enable/disable support removed, attributes
+ hotkey_bios_enabled and hotkey_enable deprecated and
+ marked for removal.
+
+0x020400: Marker for 16 LEDs support. Also, LEDs that are known
+ to not exist in a given model are not registered with
+ the LED sysfs class anymore.
+
+0x020500: Updated hotkey driver, hotkey_mask is always available
+ and it is always able to disable hot keys. Very old
+ thinkpads are properly supported. hotkey_bios_mask
+ is deprecated and marked for removal.
+
+0x020600: Marker for backlight change event support.
+
+0x020700: Support for mute-only mixers.
+ Volume control in read-only mode by default.
+ Marker for ALSA mixer support.