diff options
Diffstat (limited to 'drivers/staging/comedi/drivers/comedi_rt_timer.c')
| -rw-r--r-- | drivers/staging/comedi/drivers/comedi_rt_timer.c | 728 |
1 files changed, 0 insertions, 728 deletions
diff --git a/drivers/staging/comedi/drivers/comedi_rt_timer.c b/drivers/staging/comedi/drivers/comedi_rt_timer.c deleted file mode 100644 index f40c8cffd4bb..000000000000 --- a/drivers/staging/comedi/drivers/comedi_rt_timer.c +++ /dev/null @@ -1,728 +0,0 @@ -/* - comedi/drivers/comedi_rt_timer.c - virtual driver for using RTL timing sources - - Authors: David A. Schleef, Frank M. Hess - - COMEDI - Linux Control and Measurement Device Interface - Copyright (C) 1999,2001 David A. Schleef <ds@schleef.org> - - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or - (at your option) any later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - -************************************************************************** -*/ -/* -Driver: comedi_rt_timer -Description: Command emulator using real-time tasks -Author: ds, fmhess -Devices: -Status: works - -This driver requires RTAI or RTLinux to work correctly. It doesn't -actually drive hardware directly, but calls other drivers and uses -a real-time task to emulate commands for drivers and devices that -are incapable of native commands. Thus, you can get accurately -timed I/O on any device. - -Since the timing is all done in software, sampling jitter is much -higher than with a device that has an on-board timer, and maximum -sample rate is much lower. - -Configuration options: - [0] - minor number of device you wish to emulate commands for - [1] - subdevice number you wish to emulate commands for -*/ -/* -TODO: - Support for digital io commands could be added, except I can't see why - anyone would want to use them - What happens if device we are emulating for is de-configured? -*/ - -#include "../comedidev.h" -#include "../comedilib.h" - -#include "comedi_fc.h" - -#ifdef CONFIG_COMEDI_RTL_V1 -#include <rtl_sched.h> -#include <asm/rt_irq.h> -#endif -#ifdef CONFIG_COMEDI_RTL -#include <rtl.h> -#include <rtl_sched.h> -#include <rtl_compat.h> -#include <asm/div64.h> - -#ifndef RTLINUX_VERSION_CODE -#define RTLINUX_VERSION_CODE 0 -#endif -#ifndef RTLINUX_VERSION -#define RTLINUX_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c)) -#endif - -// begin hack to workaround broken HRT_TO_8254() function on rtlinux -#if RTLINUX_VERSION_CODE <= RTLINUX_VERSION(3,0,100) -// this function sole purpose is to divide a long long by 838 -static inline RTIME nano2count(long long ns) -{ - do_div(ns, 838); - return ns; -} - -#ifdef rt_get_time() -#undef rt_get_time() -#endif -#define rt_get_time() nano2count(gethrtime()) - -#else - -#define nano2count(x) HRT_TO_8254(x) -#endif -// end hack - -// rtl-rtai compatibility -#define rt_task_wait_period() rt_task_wait() -#define rt_pend_linux_srq(irq) rtl_global_pend_irq(irq) -#define rt_free_srq(irq) rtl_free_soft_irq(irq) -#define rt_request_srq(x,y,z) rtl_get_soft_irq(y,"timer") -#define rt_task_init(a,b,c,d,e,f,g) rt_task_init(a,b,c,d,(e)+1) -#define rt_task_resume(x) rt_task_wakeup(x) -#define rt_set_oneshot_mode() -#define start_rt_timer(x) -#define stop_rt_timer() - -#endif -#ifdef CONFIG_COMEDI_RTAI -#include <rtai.h> -#include <rtai_sched.h> - -#if RTAI_VERSION_CODE < RTAI_MANGLE_VERSION(3,3,0) -#define comedi_rt_task_context_t int -#else -#define comedi_rt_task_context_t long -#endif - -#endif - -/* This defines the fastest speed we will emulate. Note that - * without a watchdog (like in RTAI), we could easily overrun our - * task period because analog input tends to be slow. */ -#define SPEED_LIMIT 100000 /* in nanoseconds */ - -static int timer_attach(struct comedi_device * dev, struct comedi_devconfig * it); -static int timer_detach(struct comedi_device * dev); -static int timer_inttrig(struct comedi_device * dev, struct comedi_subdevice * s, - unsigned int trig_num); -static int timer_start_cmd(struct comedi_device * dev, struct comedi_subdevice * s); - -static struct comedi_driver driver_timer = { - module:THIS_MODULE, - driver_name:"comedi_rt_timer", - attach:timer_attach, - detach:timer_detach, -// open: timer_open, -}; - -COMEDI_INITCLEANUP(driver_timer); - -struct timer_private { - comedi_t *device; // device we are emulating commands for - int subd; // subdevice we are emulating commands for - RT_TASK *rt_task; // rt task that starts scans - RT_TASK *scan_task; // rt task that controls conversion timing in a scan - /* io_function can point to either an input or output function - * depending on what kind of subdevice we are emulating for */ - int (*io_function) (struct comedi_device * dev, struct comedi_cmd * cmd, - unsigned int index); - // RTIME has units of 1 = 838 nanoseconds - // time at which first scan started, used to check scan timing - RTIME start; - // time between scans - RTIME scan_period; - // time between conversions in a scan - RTIME convert_period; - // flags - volatile int stop; // indicates we should stop - volatile int rt_task_active; // indicates rt_task is servicing a struct comedi_cmd - volatile int scan_task_active; // indicates scan_task is servicing a struct comedi_cmd - unsigned timer_running:1; -}; -#define devpriv ((struct timer_private *)dev->private) - -static int timer_cancel(struct comedi_device * dev, struct comedi_subdevice * s) -{ - devpriv->stop = 1; - - return 0; -} - -// checks for scan timing error -inline static int check_scan_timing(struct comedi_device * dev, - unsigned long long scan) -{ - RTIME now, timing_error; - - now = rt_get_time(); - timing_error = now - (devpriv->start + scan * devpriv->scan_period); - if (timing_error > devpriv->scan_period) { - comedi_error(dev, "timing error"); - rt_printk("scan started %i ns late\n", timing_error * 838); - return -1; - } - - return 0; -} - -// checks for conversion timing error -inline static int check_conversion_timing(struct comedi_device * dev, - RTIME scan_start, unsigned int conversion) -{ - RTIME now, timing_error; - - now = rt_get_time(); - timing_error = - now - (scan_start + conversion * devpriv->convert_period); - if (timing_error > devpriv->convert_period) { - comedi_error(dev, "timing error"); - rt_printk("conversion started %i ns late\n", - timing_error * 838); - return -1; - } - - return 0; -} - -// devpriv->io_function for an input subdevice -static int timer_data_read(struct comedi_device * dev, struct comedi_cmd * cmd, - unsigned int index) -{ - struct comedi_subdevice *s = dev->read_subdev; - int ret; - unsigned int data; - - ret = comedi_data_read(devpriv->device, devpriv->subd, - CR_CHAN(cmd->chanlist[index]), - CR_RANGE(cmd->chanlist[index]), - CR_AREF(cmd->chanlist[index]), &data); - if (ret < 0) { - comedi_error(dev, "read error"); - return -EIO; - } - if (s->flags & SDF_LSAMPL) { - cfc_write_long_to_buffer(s, data); - } else { - comedi_buf_put(s->async, data); - } - - return 0; -} - -// devpriv->io_function for an output subdevice -static int timer_data_write(struct comedi_device * dev, struct comedi_cmd * cmd, - unsigned int index) -{ - struct comedi_subdevice *s = dev->write_subdev; - unsigned int num_bytes; - short data; - unsigned int long_data; - int ret; - - if (s->flags & SDF_LSAMPL) { - num_bytes = - cfc_read_array_from_buffer(s, &long_data, - sizeof(long_data)); - } else { - num_bytes = cfc_read_array_from_buffer(s, &data, sizeof(data)); - long_data = data; - } - - if (num_bytes == 0) { - comedi_error(dev, "buffer underrun"); - return -EAGAIN; - } - ret = comedi_data_write(devpriv->device, devpriv->subd, - CR_CHAN(cmd->chanlist[index]), - CR_RANGE(cmd->chanlist[index]), - CR_AREF(cmd->chanlist[index]), long_data); - if (ret < 0) { - comedi_error(dev, "write error"); - return -EIO; - } - - return 0; -} - -// devpriv->io_function for DIO subdevices -static int timer_dio_read(struct comedi_device * dev, struct comedi_cmd * cmd, - unsigned int index) -{ - struct comedi_subdevice *s = dev->read_subdev; - int ret; - unsigned int data; - - ret = comedi_dio_bitfield(devpriv->device, devpriv->subd, 0, &data); - if (ret < 0) { - comedi_error(dev, "read error"); - return -EIO; - } - - if (s->flags & SDF_LSAMPL) - cfc_write_long_to_buffer(s, data); - else - cfc_write_to_buffer(s, data); - - return 0; -} - -// performs scans -static void scan_task_func(comedi_rt_task_context_t d) -{ - struct comedi_device *dev = (struct comedi_device *) d; - struct comedi_subdevice *s = dev->subdevices + 0; - struct comedi_async *async = s->async; - struct comedi_cmd *cmd = &async->cmd; - int i, ret; - unsigned long long n; - RTIME scan_start; - - // every struct comedi_cmd causes one execution of while loop - while (1) { - devpriv->scan_task_active = 1; - // each for loop completes one scan - for (n = 0; n < cmd->stop_arg || cmd->stop_src == TRIG_NONE; - n++) { - if (n) { - // suspend task until next scan - ret = rt_task_suspend(devpriv->scan_task); - if (ret < 0) { - comedi_error(dev, - "error suspending scan task"); - async->events |= COMEDI_CB_ERROR; - goto cleanup; - } - } - // check if stop flag was set (by timer_cancel()) - if (devpriv->stop) - goto cleanup; - ret = check_scan_timing(dev, n); - if (ret < 0) { - async->events |= COMEDI_CB_ERROR; - goto cleanup; - } - scan_start = rt_get_time(); - for (i = 0; i < cmd->scan_end_arg; i++) { - // conversion timing - if (cmd->convert_src == TRIG_TIMER && i) { - rt_task_wait_period(); - ret = check_conversion_timing(dev, - scan_start, i); - if (ret < 0) { - async->events |= - COMEDI_CB_ERROR; - goto cleanup; - } - } - ret = devpriv->io_function(dev, cmd, i); - if (ret < 0) { - async->events |= COMEDI_CB_ERROR; - goto cleanup; - } - } - s->async->events |= COMEDI_CB_BLOCK; - comedi_event(dev, s); - s->async->events = 0; - } - - cleanup: - - comedi_unlock(devpriv->device, devpriv->subd); - async->events |= COMEDI_CB_EOA; - comedi_event(dev, s); - async->events = 0; - devpriv->scan_task_active = 0; - // suspend task until next struct comedi_cmd - rt_task_suspend(devpriv->scan_task); - } -} - -static void timer_task_func(comedi_rt_task_context_t d) -{ - struct comedi_device *dev = (struct comedi_device *) d; - struct comedi_subdevice *s = dev->subdevices + 0; - struct comedi_cmd *cmd = &s->async->cmd; - int ret; - unsigned long long n; - - // every struct comedi_cmd causes one execution of while loop - while (1) { - devpriv->rt_task_active = 1; - devpriv->scan_task_active = 1; - devpriv->start = rt_get_time(); - - for (n = 0; n < cmd->stop_arg || cmd->stop_src == TRIG_NONE; - n++) { - // scan timing - if (n) - rt_task_wait_period(); - if (devpriv->scan_task_active == 0) { - goto cleanup; - } - ret = rt_task_make_periodic(devpriv->scan_task, - devpriv->start + devpriv->scan_period * n, - devpriv->convert_period); - if (ret < 0) { - comedi_error(dev, "bug!"); - } - } - - cleanup: - - devpriv->rt_task_active = 0; - // suspend until next struct comedi_cmd - rt_task_suspend(devpriv->rt_task); - } -} - -static int timer_insn(struct comedi_device * dev, struct comedi_subdevice * s, - struct comedi_insn * insn, unsigned int * data) -{ - struct comedi_insn xinsn = *insn; - - xinsn.data = data; - xinsn.subdev = devpriv->subd; - - return comedi_do_insn(devpriv->device, &xinsn); -} - -static int cmdtest_helper(struct comedi_cmd * cmd, - unsigned int start_src, - unsigned int scan_begin_src, - unsigned int convert_src, - unsigned int scan_end_src, unsigned int stop_src) -{ - int err = 0; - int tmp; - - tmp = cmd->start_src; - cmd->start_src &= start_src; - if (!cmd->start_src || tmp != cmd->start_src) - err++; - - tmp = cmd->scan_begin_src; - cmd->scan_begin_src &= scan_begin_src; - if (!cmd->scan_begin_src || tmp != cmd->scan_begin_src) - err++; - - tmp = cmd->convert_src; - cmd->convert_src &= convert_src; - if (!cmd->convert_src || tmp != cmd->convert_src) - err++; - - tmp = cmd->scan_end_src; - cmd->scan_end_src &= scan_end_src; - if (!cmd->scan_end_src || tmp != cmd->scan_end_src) - err++; - - tmp = cmd->stop_src; - cmd->stop_src &= stop_src; - if (!cmd->stop_src || tmp != cmd->stop_src) - err++; - - return err; -} - -static int timer_cmdtest(struct comedi_device * dev, struct comedi_subdevice * s, - struct comedi_cmd * cmd) -{ - int err = 0; - unsigned int start_src = 0; - - if (s->type == COMEDI_SUBD_AO) - start_src = TRIG_INT; - else - start_src = TRIG_NOW; - - err = cmdtest_helper(cmd, start_src, /* start_src */ - TRIG_TIMER | TRIG_FOLLOW, /* scan_begin_src */ - TRIG_NOW | TRIG_TIMER, /* convert_src */ - TRIG_COUNT, /* scan_end_src */ - TRIG_COUNT | TRIG_NONE); /* stop_src */ - if (err) - return 1; - - /* step 2: make sure trigger sources are unique and mutually - * compatible */ - - if (cmd->start_src != TRIG_NOW && cmd->start_src != TRIG_INT) - err++; - if (cmd->scan_begin_src != TRIG_TIMER && - cmd->scan_begin_src != TRIG_FOLLOW) - err++; - if (cmd->convert_src != TRIG_TIMER && cmd->convert_src != TRIG_NOW) - err++; - if (cmd->stop_src != TRIG_COUNT && cmd->stop_src != TRIG_NONE) - err++; - if (cmd->scan_begin_src == TRIG_FOLLOW - && cmd->convert_src != TRIG_TIMER) - err++; - if (cmd->convert_src == TRIG_NOW && cmd->scan_begin_src != TRIG_TIMER) - err++; - - if (err) - return 2; - - /* step 3: make sure arguments are trivially compatible */ - // limit frequency, this is fairly arbitrary - if (cmd->scan_begin_src == TRIG_TIMER) { - if (cmd->scan_begin_arg < SPEED_LIMIT) { - cmd->scan_begin_arg = SPEED_LIMIT; - err++; - } - } - if (cmd->convert_src == TRIG_TIMER) { - if (cmd->convert_arg < SPEED_LIMIT) { - cmd->convert_arg = SPEED_LIMIT; - err++; - } - } - // make sure conversion and scan frequencies are compatible - if (cmd->convert_src == TRIG_TIMER && cmd->scan_begin_src == TRIG_TIMER) { - if (cmd->convert_arg * cmd->scan_end_arg > cmd->scan_begin_arg) { - cmd->scan_begin_arg = - cmd->convert_arg * cmd->scan_end_arg; - err++; - } - } - if (err) - return 3; - - /* step 4: fix up and arguments */ - if (err) - return 4; - - return 0; -} - -static int timer_cmd(struct comedi_device * dev, struct comedi_subdevice * s) -{ - int ret; - struct comedi_cmd *cmd = &s->async->cmd; - - /* hack attack: drivers are not supposed to do this: */ - dev->rt = 1; - - // make sure tasks have finished cleanup of last struct comedi_cmd - if (devpriv->rt_task_active || devpriv->scan_task_active) - return -EBUSY; - - ret = comedi_lock(devpriv->device, devpriv->subd); - if (ret < 0) { - comedi_error(dev, "failed to obtain lock"); - return ret; - } - switch (cmd->scan_begin_src) { - case TRIG_TIMER: - devpriv->scan_period = nano2count(cmd->scan_begin_arg); - break; - case TRIG_FOLLOW: - devpriv->scan_period = - nano2count(cmd->convert_arg * cmd->scan_end_arg); - break; - default: - comedi_error(dev, "bug setting scan period!"); - return -1; - break; - } - switch (cmd->convert_src) { - case TRIG_TIMER: - devpriv->convert_period = nano2count(cmd->convert_arg); - break; - case TRIG_NOW: - devpriv->convert_period = 1; - break; - default: - comedi_error(dev, "bug setting conversion period!"); - return -1; - break; - } - - if (cmd->start_src == TRIG_NOW) - return timer_start_cmd(dev, s); - - s->async->inttrig = timer_inttrig; - - return 0; -} - -static int timer_inttrig(struct comedi_device * dev, struct comedi_subdevice * s, - unsigned int trig_num) -{ - if (trig_num != 0) - return -EINVAL; - - s->async->inttrig = NULL; - - return timer_start_cmd(dev, s); -} - -static int timer_start_cmd(struct comedi_device * dev, struct comedi_subdevice * s) -{ - struct comedi_async *async = s->async; - struct comedi_cmd *cmd = &async->cmd; - RTIME now, delay, period; - int ret; - - devpriv->stop = 0; - s->async->events = 0; - - if (cmd->start_src == TRIG_NOW) - delay = nano2count(cmd->start_arg); - else - delay = 0; - - now = rt_get_time(); - /* Using 'period' this way gets around some weird bug in gcc-2.95.2 - * that generates the compile error 'internal error--unrecognizable insn' - * when rt_task_make_period() is called (observed with rtlinux-3.1, linux-2.2.19). - * - fmhess */ - period = devpriv->scan_period; - ret = rt_task_make_periodic(devpriv->rt_task, now + delay, period); - if (ret < 0) { - comedi_error(dev, "error starting rt_task"); - return ret; - } - return 0; -} - -static int timer_attach(struct comedi_device * dev, struct comedi_devconfig * it) -{ - int ret; - struct comedi_subdevice *s, *emul_s; - struct comedi_device *emul_dev; - /* These should probably be devconfig options[] */ - const int timer_priority = 4; - const int scan_priority = timer_priority + 1; - char path[20]; - - printk("comedi%d: timer: ", dev->minor); - - dev->board_name = "timer"; - - if ((ret = alloc_subdevices(dev, 1)) < 0) - return ret; - if ((ret = alloc_private(dev, sizeof(struct timer_private))) < 0) - return ret; - - sprintf(path, "/dev/comedi%d", it->options[0]); - devpriv->device = comedi_open(path); - devpriv->subd = it->options[1]; - - printk("emulating commands for minor %i, subdevice %d\n", - it->options[0], devpriv->subd); - - emul_dev = devpriv->device; - emul_s = emul_dev->subdevices + devpriv->subd; - - // input or output subdevice - s = dev->subdevices + 0; - s->type = emul_s->type; - s->subdev_flags = emul_s->subdev_flags; /* SDF_GROUND (to fool check_driver) */ - s->n_chan = emul_s->n_chan; - s->len_chanlist = 1024; - s->do_cmd = timer_cmd; - s->do_cmdtest = timer_cmdtest; - s->cancel = timer_cancel; - s->maxdata = emul_s->maxdata; - s->range_table = emul_s->range_table; - s->range_table_list = emul_s->range_table_list; - switch (emul_s->type) { - case COMEDI_SUBD_AI: - s->insn_read = timer_insn; - dev->read_subdev = s; - s->subdev_flags |= SDF_CMD_READ; - devpriv->io_function = timer_data_read; - break; - case COMEDI_SUBD_AO: - s->insn_write = timer_insn; - s->insn_read = timer_insn; - dev->write_subdev = s; - s->subdev_flags |= SDF_CMD_WRITE; - devpriv->io_function = timer_data_write; - break; - case COMEDI_SUBD_DIO: - s->insn_write = timer_insn; - s->insn_read = timer_insn; - s->insn_bits = timer_insn; - dev->read_subdev = s; - s->subdev_flags |= SDF_CMD_READ; - devpriv->io_function = timer_dio_read; - break; - default: - comedi_error(dev, "failed to determine subdevice type!"); - return -EINVAL; - } - - rt_set_oneshot_mode(); - start_rt_timer(1); - devpriv->timer_running = 1; - - devpriv->rt_task = kzalloc(sizeof(RT_TASK), GFP_KERNEL); - - // initialize real-time tasks - ret = rt_task_init(devpriv->rt_task, timer_task_func, - (comedi_rt_task_context_t) dev, 3000, timer_priority, 0, 0); - if (ret < 0) { - comedi_error(dev, "error initalizing rt_task"); - kfree(devpriv->rt_task); - devpriv->rt_task = 0; - return ret; - } - - devpriv->scan_task = kzalloc(sizeof(RT_TASK), GFP_KERNEL); - - ret = rt_task_init(devpriv->scan_task, scan_task_func, - (comedi_rt_task_context_t) dev, 3000, scan_priority, 0, 0); - if (ret < 0) { - comedi_error(dev, "error initalizing scan_task"); - kfree(devpriv->scan_task); - devpriv->scan_task = 0; - return ret; - } - - return 1; -} - -// free allocated resources -static int timer_detach(struct comedi_device * dev) -{ - printk("comedi%d: timer: remove\n", dev->minor); - - if (devpriv) { - if (devpriv->rt_task) { - rt_task_delete(devpriv->rt_task); - kfree(devpriv->rt_task); - } - if (devpriv->scan_task) { - rt_task_delete(devpriv->scan_task); - kfree(devpriv->scan_task); - } - if (devpriv->timer_running) - stop_rt_timer(); - if (devpriv->device) - comedi_close(devpriv->device); - } - return 0; -} |