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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/cris/arch-v10/drivers/ds1302.c
downloadconfigs-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/cris/arch-v10/drivers/ds1302.c')
-rw-r--r--arch/cris/arch-v10/drivers/ds1302.c602
1 files changed, 602 insertions, 0 deletions
diff --git a/arch/cris/arch-v10/drivers/ds1302.c b/arch/cris/arch-v10/drivers/ds1302.c
new file mode 100644
index 00000000000..fba530fcfae
--- /dev/null
+++ b/arch/cris/arch-v10/drivers/ds1302.c
@@ -0,0 +1,602 @@
+/*!***************************************************************************
+*!
+*! FILE NAME : ds1302.c
+*!
+*! DESCRIPTION: Implements an interface for the DS1302 RTC through Etrax I/O
+*!
+*! Functions exported: ds1302_readreg, ds1302_writereg, ds1302_init
+*!
+*! $Log: ds1302.c,v $
+*! Revision 1.14 2004/08/24 06:48:43 starvik
+*! Whitespace cleanup
+*!
+*! Revision 1.13 2004/05/28 09:26:59 starvik
+*! Modified I2C initialization to work in 2.6.
+*!
+*! Revision 1.12 2004/05/14 07:58:03 starvik
+*! Merge of changes from 2.4
+*!
+*! Revision 1.10 2004/02/04 09:25:12 starvik
+*! Merge of Linux 2.6.2
+*!
+*! Revision 1.9 2003/07/04 08:27:37 starvik
+*! Merge of Linux 2.5.74
+*!
+*! Revision 1.8 2003/04/09 05:20:47 starvik
+*! Merge of Linux 2.5.67
+*!
+*! Revision 1.6 2003/01/09 14:42:51 starvik
+*! Merge of Linux 2.5.55
+*!
+*! Revision 1.4 2002/12/11 13:13:57 starvik
+*! Added arch/ to v10 specific includes
+*! Added fix from Linux 2.4 in serial.c (flush_to_flip_buffer)
+*!
+*! Revision 1.3 2002/11/20 11:56:10 starvik
+*! Merge of Linux 2.5.48
+*!
+*! Revision 1.2 2002/11/18 13:16:06 starvik
+*! Linux 2.5 port of latest 2.4 drivers
+*!
+*! Revision 1.15 2002/10/11 16:14:33 johana
+*! Added CONFIG_ETRAX_DS1302_TRICKLE_CHARGE and initial setting of the
+*! trcklecharge register.
+*!
+*! Revision 1.14 2002/10/10 12:15:38 magnusmn
+*! Added support for having the RST signal on bit g0
+*!
+*! Revision 1.13 2002/05/29 15:16:08 johana
+*! Removed unused variables.
+*!
+*! Revision 1.12 2002/04/10 15:35:25 johana
+*! Moved probe function closer to init function and marked it __init.
+*!
+*! Revision 1.11 2001/06/14 12:35:52 jonashg
+*! The ATA hack is back. It is unfortunately the only way to set g27 to output.
+*!
+*! Revision 1.9 2001/06/14 10:00:14 jonashg
+*! No need for tempudelay to be inline anymore (had to adjust the usec to
+*! loops conversion because of this to make it slow enough to be a udelay).
+*!
+*! Revision 1.8 2001/06/14 08:06:32 jonashg
+*! Made tempudelay delay usecs (well, just a tad more).
+*!
+*! Revision 1.7 2001/06/13 14:18:11 jonashg
+*! Only allow processes with SYS_TIME capability to set time and charge.
+*!
+*! Revision 1.6 2001/06/12 15:22:07 jonashg
+*! * Made init function __init.
+*! * Parameter to out_byte() is unsigned char.
+*! * The magic number 42 has got a name.
+*! * Removed comment about /proc (nothing is exported there).
+*!
+*! Revision 1.5 2001/06/12 14:35:13 jonashg
+*! Gave the module a name and added it to printk's.
+*!
+*! Revision 1.4 2001/05/31 14:53:40 jonashg
+*! Made tempudelay() inline so that the watchdog doesn't reset (see
+*! function comment).
+*!
+*! Revision 1.3 2001/03/26 16:03:06 bjornw
+*! Needs linux/config.h
+*!
+*! Revision 1.2 2001/03/20 19:42:00 bjornw
+*! Use the ETRAX prefix on the DS1302 options
+*!
+*! Revision 1.1 2001/03/20 09:13:50 magnusmn
+*! Linux 2.4 port
+*!
+*! Revision 1.10 2000/07/05 15:38:23 bjornw
+*! Dont update kernel time when a RTC_SET_TIME is done
+*!
+*! Revision 1.9 2000/03/02 15:42:59 macce
+*! * Hack to make RTC work on all 2100/2400
+*!
+*! Revision 1.8 2000/02/23 16:59:18 torbjore
+*! added setup of R_GEN_CONFIG when RTC is connected to the generic port.
+*!
+*! Revision 1.7 2000/01/17 15:51:43 johana
+*! Added RTC_SET_CHARGE ioctl to enable trickle charger.
+*!
+*! Revision 1.6 1999/10/27 13:19:47 bjornw
+*! Added update_xtime_from_cmos which reads back the updated RTC into the kernel.
+*! /dev/rtc calls it now.
+*!
+*! Revision 1.5 1999/10/27 12:39:37 bjornw
+*! Disabled superuser check. Anyone can now set the time.
+*!
+*! Revision 1.4 1999/09/02 13:27:46 pkj
+*! Added shadow for R_PORT_PB_CONFIG.
+*! Renamed port_g_shadow to port_g_data_shadow.
+*!
+*! Revision 1.3 1999/09/02 08:28:06 pkj
+*! Made it possible to select either port PB or the generic port for the RST
+*! signal line to the DS1302 RTC.
+*! Also make sure the RST bit is configured as output on Port PB (if used).
+*!
+*! Revision 1.2 1999/09/01 14:47:20 bjornw
+*! Added support for /dev/rtc operations with ioctl RD_TIME and SET_TIME to read
+*! and set the date. Register as major 121.
+*!
+*! Revision 1.1 1999/09/01 09:45:29 bjornw
+*! Implemented a DS1302 RTC driver.
+*!
+*!
+*! ---------------------------------------------------------------------------
+*!
+*! (C) Copyright 1999, 2000, 2001 Axis Communications AB, LUND, SWEDEN
+*!
+*! $Id: ds1302.c,v 1.14 2004/08/24 06:48:43 starvik Exp $
+*!
+*!***************************************************************************/
+
+#include <linux/config.h>
+
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/miscdevice.h>
+#include <linux/delay.h>
+#include <linux/bcd.h>
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/arch/svinto.h>
+#include <asm/io.h>
+#include <asm/rtc.h>
+
+#define RTC_MAJOR_NR 121 /* local major, change later */
+
+static const char ds1302_name[] = "ds1302";
+
+/* The DS1302 might be connected to different bits on different products.
+ * It has three signals - SDA, SCL and RST. RST and SCL are always outputs,
+ * but SDA can have a selected direction.
+ * For now, only PORT_PB is hardcoded.
+ */
+
+/* The RST bit may be on either the Generic Port or Port PB. */
+#ifdef CONFIG_ETRAX_DS1302_RST_ON_GENERIC_PORT
+#define TK_RST_OUT(x) REG_SHADOW_SET(R_PORT_G_DATA, port_g_data_shadow, CONFIG_ETRAX_DS1302_RSTBIT, x)
+#define TK_RST_DIR(x)
+#else
+#define TK_RST_OUT(x) REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, CONFIG_ETRAX_DS1302_RSTBIT, x)
+#define TK_RST_DIR(x) REG_SHADOW_SET(R_PORT_PB_DIR, port_pb_dir_shadow, CONFIG_ETRAX_DS1302_RSTBIT, x)
+#endif
+
+
+#define TK_SDA_OUT(x) REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, CONFIG_ETRAX_DS1302_SDABIT, x)
+#define TK_SCL_OUT(x) REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, CONFIG_ETRAX_DS1302_SCLBIT, x)
+
+#define TK_SDA_IN() ((*R_PORT_PB_READ >> CONFIG_ETRAX_DS1302_SDABIT) & 1)
+/* 1 is out, 0 is in */
+#define TK_SDA_DIR(x) REG_SHADOW_SET(R_PORT_PB_DIR, port_pb_dir_shadow, CONFIG_ETRAX_DS1302_SDABIT, x)
+#define TK_SCL_DIR(x) REG_SHADOW_SET(R_PORT_PB_DIR, port_pb_dir_shadow, CONFIG_ETRAX_DS1302_SCLBIT, x)
+
+
+/*
+ * The reason for tempudelay and not udelay is that loops_per_usec
+ * (used in udelay) is not set when functions here are called from time.c
+ */
+
+static void tempudelay(int usecs)
+{
+ volatile int loops;
+
+ for(loops = usecs * 12; loops > 0; loops--)
+ /* nothing */;
+}
+
+
+/* Send 8 bits. */
+static void
+out_byte(unsigned char x)
+{
+ int i;
+ TK_SDA_DIR(1);
+ for (i = 8; i--;) {
+ /* The chip latches incoming bits on the rising edge of SCL. */
+ TK_SCL_OUT(0);
+ TK_SDA_OUT(x & 1);
+ tempudelay(1);
+ TK_SCL_OUT(1);
+ tempudelay(1);
+ x >>= 1;
+ }
+ TK_SDA_DIR(0);
+}
+
+static unsigned char
+in_byte(void)
+{
+ unsigned char x = 0;
+ int i;
+
+ /* Read byte. Bits come LSB first, on the falling edge of SCL.
+ * Assume SDA is in input direction already.
+ */
+ TK_SDA_DIR(0);
+
+ for (i = 8; i--;) {
+ TK_SCL_OUT(0);
+ tempudelay(1);
+ x >>= 1;
+ x |= (TK_SDA_IN() << 7);
+ TK_SCL_OUT(1);
+ tempudelay(1);
+ }
+
+ return x;
+}
+
+/* Prepares for a transaction by de-activating RST (active-low). */
+
+static void
+start(void)
+{
+ TK_SCL_OUT(0);
+ tempudelay(1);
+ TK_RST_OUT(0);
+ tempudelay(5);
+ TK_RST_OUT(1);
+}
+
+/* Ends a transaction by taking RST active again. */
+
+static void
+stop(void)
+{
+ tempudelay(2);
+ TK_RST_OUT(0);
+}
+
+/* Enable writing. */
+
+static void
+ds1302_wenable(void)
+{
+ start();
+ out_byte(0x8e); /* Write control register */
+ out_byte(0x00); /* Disable write protect bit 7 = 0 */
+ stop();
+}
+
+/* Disable writing. */
+
+static void
+ds1302_wdisable(void)
+{
+ start();
+ out_byte(0x8e); /* Write control register */
+ out_byte(0x80); /* Disable write protect bit 7 = 0 */
+ stop();
+}
+
+
+
+/* Read a byte from the selected register in the DS1302. */
+
+unsigned char
+ds1302_readreg(int reg)
+{
+ unsigned char x;
+
+ start();
+ out_byte(0x81 | (reg << 1)); /* read register */
+ x = in_byte();
+ stop();
+
+ return x;
+}
+
+/* Write a byte to the selected register. */
+
+void
+ds1302_writereg(int reg, unsigned char val)
+{
+#ifndef CONFIG_ETRAX_RTC_READONLY
+ int do_writereg = 1;
+#else
+ int do_writereg = 0;
+
+ if (reg == RTC_TRICKLECHARGER)
+ do_writereg = 1;
+#endif
+
+ if (do_writereg) {
+ ds1302_wenable();
+ start();
+ out_byte(0x80 | (reg << 1)); /* write register */
+ out_byte(val);
+ stop();
+ ds1302_wdisable();
+ }
+}
+
+void
+get_rtc_time(struct rtc_time *rtc_tm)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ local_irq_disable();
+
+ rtc_tm->tm_sec = CMOS_READ(RTC_SECONDS);
+ rtc_tm->tm_min = CMOS_READ(RTC_MINUTES);
+ rtc_tm->tm_hour = CMOS_READ(RTC_HOURS);
+ rtc_tm->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH);
+ rtc_tm->tm_mon = CMOS_READ(RTC_MONTH);
+ rtc_tm->tm_year = CMOS_READ(RTC_YEAR);
+
+ local_irq_restore(flags);
+
+ BCD_TO_BIN(rtc_tm->tm_sec);
+ BCD_TO_BIN(rtc_tm->tm_min);
+ BCD_TO_BIN(rtc_tm->tm_hour);
+ BCD_TO_BIN(rtc_tm->tm_mday);
+ BCD_TO_BIN(rtc_tm->tm_mon);
+ BCD_TO_BIN(rtc_tm->tm_year);
+
+ /*
+ * Account for differences between how the RTC uses the values
+ * and how they are defined in a struct rtc_time;
+ */
+
+ if (rtc_tm->tm_year <= 69)
+ rtc_tm->tm_year += 100;
+
+ rtc_tm->tm_mon--;
+}
+
+static unsigned char days_in_mo[] =
+ {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
+
+/* ioctl that supports RTC_RD_TIME and RTC_SET_TIME (read and set time/date). */
+
+static int
+rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ unsigned long flags;
+
+ switch(cmd) {
+ case RTC_RD_TIME: /* read the time/date from RTC */
+ {
+ struct rtc_time rtc_tm;
+
+ memset(&rtc_tm, 0, sizeof (struct rtc_time));
+ get_rtc_time(&rtc_tm);
+ if (copy_to_user((struct rtc_time*)arg, &rtc_tm, sizeof(struct rtc_time)))
+ return -EFAULT;
+ return 0;
+ }
+
+ case RTC_SET_TIME: /* set the RTC */
+ {
+ struct rtc_time rtc_tm;
+ unsigned char mon, day, hrs, min, sec, leap_yr;
+ unsigned int yrs;
+
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+
+ if (copy_from_user(&rtc_tm, (struct rtc_time*)arg, sizeof(struct rtc_time)))
+ return -EFAULT;
+
+ yrs = rtc_tm.tm_year + 1900;
+ mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */
+ day = rtc_tm.tm_mday;
+ hrs = rtc_tm.tm_hour;
+ min = rtc_tm.tm_min;
+ sec = rtc_tm.tm_sec;
+
+
+ if ((yrs < 1970) || (yrs > 2069))
+ return -EINVAL;
+
+ leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
+
+ if ((mon > 12) || (day == 0))
+ return -EINVAL;
+
+ if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
+ return -EINVAL;
+
+ if ((hrs >= 24) || (min >= 60) || (sec >= 60))
+ return -EINVAL;
+
+ if (yrs >= 2000)
+ yrs -= 2000; /* RTC (0, 1, ... 69) */
+ else
+ yrs -= 1900; /* RTC (70, 71, ... 99) */
+
+ BIN_TO_BCD(sec);
+ BIN_TO_BCD(min);
+ BIN_TO_BCD(hrs);
+ BIN_TO_BCD(day);
+ BIN_TO_BCD(mon);
+ BIN_TO_BCD(yrs);
+
+ local_irq_save(flags);
+ local_irq_disable();
+ CMOS_WRITE(yrs, RTC_YEAR);
+ CMOS_WRITE(mon, RTC_MONTH);
+ CMOS_WRITE(day, RTC_DAY_OF_MONTH);
+ CMOS_WRITE(hrs, RTC_HOURS);
+ CMOS_WRITE(min, RTC_MINUTES);
+ CMOS_WRITE(sec, RTC_SECONDS);
+ local_irq_restore(flags);
+
+ /* Notice that at this point, the RTC is updated but
+ * the kernel is still running with the old time.
+ * You need to set that separately with settimeofday
+ * or adjtimex.
+ */
+ return 0;
+ }
+
+ case RTC_SET_CHARGE: /* set the RTC TRICKLE CHARGE register */
+ {
+ int tcs_val;
+
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+
+ if(copy_from_user(&tcs_val, (int*)arg, sizeof(int)))
+ return -EFAULT;
+
+ tcs_val = RTC_TCR_PATTERN | (tcs_val & 0x0F);
+ ds1302_writereg(RTC_TRICKLECHARGER, tcs_val);
+ return 0;
+ }
+ case RTC_VLOW_RD:
+ {
+ /* TODO:
+ * Implement voltage low detection support
+ */
+ printk(KERN_WARNING "DS1302: RTC Voltage Low detection"
+ " is not supported\n");
+ return 0;
+ }
+ case RTC_VLOW_SET:
+ {
+ /* TODO:
+ * Nothing to do since Voltage Low detection is not supported
+ */
+ return 0;
+ }
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+static void
+print_rtc_status(void)
+{
+ struct rtc_time tm;
+
+ get_rtc_time(&tm);
+
+ /*
+ * There is no way to tell if the luser has the RTC set for local
+ * time or for Universal Standard Time (GMT). Probably local though.
+ */
+
+ printk(KERN_INFO "rtc_time\t: %02d:%02d:%02d\n",
+ tm.tm_hour, tm.tm_min, tm.tm_sec);
+ printk(KERN_INFO "rtc_date\t: %04d-%02d-%02d\n",
+ tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
+}
+
+/* The various file operations we support. */
+
+static struct file_operations rtc_fops = {
+ .owner = THIS_MODULE,
+ .ioctl = rtc_ioctl,
+};
+
+/* Probe for the chip by writing something to its RAM and try reading it back. */
+
+#define MAGIC_PATTERN 0x42
+
+static int __init
+ds1302_probe(void)
+{
+ int retval, res;
+
+ TK_RST_DIR(1);
+ TK_SCL_DIR(1);
+ TK_SDA_DIR(0);
+
+ /* Try to talk to timekeeper. */
+
+ ds1302_wenable();
+ start();
+ out_byte(0xc0); /* write RAM byte 0 */
+ out_byte(MAGIC_PATTERN); /* write something magic */
+ start();
+ out_byte(0xc1); /* read RAM byte 0 */
+
+ if((res = in_byte()) == MAGIC_PATTERN) {
+ stop();
+ ds1302_wdisable();
+ printk(KERN_INFO "%s: RTC found.\n", ds1302_name);
+ printk(KERN_INFO "%s: SDA, SCL, RST on PB%i, PB%i, %s%i\n",
+ ds1302_name,
+ CONFIG_ETRAX_DS1302_SDABIT,
+ CONFIG_ETRAX_DS1302_SCLBIT,
+#ifdef CONFIG_ETRAX_DS1302_RST_ON_GENERIC_PORT
+ "GENIO",
+#else
+ "PB",
+#endif
+ CONFIG_ETRAX_DS1302_RSTBIT);
+ print_rtc_status();
+ retval = 1;
+ } else {
+ stop();
+ retval = 0;
+ }
+
+ return retval;
+}
+
+
+/* Just probe for the RTC and register the device to handle the ioctl needed. */
+
+int __init
+ds1302_init(void)
+{
+ i2c_init();
+
+ if (!ds1302_probe()) {
+#ifdef CONFIG_ETRAX_DS1302_RST_ON_GENERIC_PORT
+#if CONFIG_ETRAX_DS1302_RSTBIT == 27
+ /*
+ * The only way to set g27 to output is to enable ATA.
+ *
+ * Make sure that R_GEN_CONFIG is setup correct.
+ */
+ genconfig_shadow = ((genconfig_shadow &
+ ~IO_MASK(R_GEN_CONFIG, ata)) |
+ (IO_STATE(R_GEN_CONFIG, ata, select)));
+ *R_GEN_CONFIG = genconfig_shadow;
+#elif CONFIG_ETRAX_DS1302_RSTBIT == 0
+
+ /* Set the direction of this bit to out. */
+ genconfig_shadow = ((genconfig_shadow &
+ ~IO_MASK(R_GEN_CONFIG, g0dir)) |
+ (IO_STATE(R_GEN_CONFIG, g0dir, out)));
+ *R_GEN_CONFIG = genconfig_shadow;
+#endif
+ if (!ds1302_probe()) {
+ printk(KERN_WARNING "%s: RTC not found.\n", ds1302_name);
+ return -1;
+ }
+#else
+ printk(KERN_WARNING "%s: RTC not found.\n", ds1302_name);
+ return -1;
+#endif
+ }
+ /* Initialise trickle charger */
+ ds1302_writereg(RTC_TRICKLECHARGER,
+ RTC_TCR_PATTERN |(CONFIG_ETRAX_DS1302_TRICKLE_CHARGE & 0x0F));
+ /* Start clock by resetting CLOCK_HALT */
+ ds1302_writereg(RTC_SECONDS, (ds1302_readreg(RTC_SECONDS) & 0x7F));
+ return 0;
+}
+
+static int __init ds1302_register(void)
+{
+ ds1302_init();
+ if (register_chrdev(RTC_MAJOR_NR, ds1302_name, &rtc_fops)) {
+ printk(KERN_INFO "%s: unable to get major %d for rtc\n",
+ ds1302_name, RTC_MAJOR_NR);
+ return -1;
+ }
+ return 0;
+
+}
+
+module_init(ds1302_register);