linux/drivers/comedi/drivers/addi_watchdog.c
Ian Abbott df0e68c1e9 comedi: Move the main COMEDI headers
Move the main COMEDI driver headers out of "drivers/comedi/" into new
directory "include/linux/comedi/".  These are "comedidev.h",
"comedilib.h", "comedi_pci.h", "comedi_pcmcia.h", and "comedi_usb.h".
Additionally, move the user-space API header "comedi.h" into
"include/uapi/linux/" and add "WITH Linux-syscall-note" to its
SPDX-License-Identifier.

Update the "COMEDI DRIVERS" section of the MAINTAINERS file to account
for these changes.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20211117120604.117740-2-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-26 16:48:59 +01:00

141 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* COMEDI driver for the watchdog subdevice found on some addi-data boards
* Copyright (c) 2013 H Hartley Sweeten <hsweeten@visionengravers.com>
*
* Based on implementations in various addi-data COMEDI drivers.
*
* COMEDI - Linux Control and Measurement Device Interface
* Copyright (C) 1998 David A. Schleef <ds@schleef.org>
*/
#include <linux/module.h>
#include <linux/comedi/comedidev.h>
#include "addi_tcw.h"
#include "addi_watchdog.h"
struct addi_watchdog_private {
unsigned long iobase;
unsigned int wdog_ctrl;
};
/*
* The watchdog subdevice is configured with two INSN_CONFIG instructions:
*
* Enable the watchdog and set the reload timeout:
* data[0] = INSN_CONFIG_ARM
* data[1] = timeout reload value
*
* Disable the watchdog:
* data[0] = INSN_CONFIG_DISARM
*/
static int addi_watchdog_insn_config(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn,
unsigned int *data)
{
struct addi_watchdog_private *spriv = s->private;
unsigned int reload;
switch (data[0]) {
case INSN_CONFIG_ARM:
spriv->wdog_ctrl = ADDI_TCW_CTRL_ENA;
reload = data[1] & s->maxdata;
outl(reload, spriv->iobase + ADDI_TCW_RELOAD_REG);
/* Time base is 20ms, let the user know the timeout */
dev_info(dev->class_dev, "watchdog enabled, timeout:%dms\n",
20 * reload + 20);
break;
case INSN_CONFIG_DISARM:
spriv->wdog_ctrl = 0;
break;
default:
return -EINVAL;
}
outl(spriv->wdog_ctrl, spriv->iobase + ADDI_TCW_CTRL_REG);
return insn->n;
}
static int addi_watchdog_insn_read(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn,
unsigned int *data)
{
struct addi_watchdog_private *spriv = s->private;
int i;
for (i = 0; i < insn->n; i++)
data[i] = inl(spriv->iobase + ADDI_TCW_STATUS_REG);
return insn->n;
}
static int addi_watchdog_insn_write(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn,
unsigned int *data)
{
struct addi_watchdog_private *spriv = s->private;
int i;
if (spriv->wdog_ctrl == 0) {
dev_warn(dev->class_dev, "watchdog is disabled\n");
return -EINVAL;
}
/* "ping" the watchdog */
for (i = 0; i < insn->n; i++) {
outl(spriv->wdog_ctrl | ADDI_TCW_CTRL_TRIG,
spriv->iobase + ADDI_TCW_CTRL_REG);
}
return insn->n;
}
void addi_watchdog_reset(unsigned long iobase)
{
outl(0x0, iobase + ADDI_TCW_CTRL_REG);
outl(0x0, iobase + ADDI_TCW_RELOAD_REG);
}
EXPORT_SYMBOL_GPL(addi_watchdog_reset);
int addi_watchdog_init(struct comedi_subdevice *s, unsigned long iobase)
{
struct addi_watchdog_private *spriv;
spriv = comedi_alloc_spriv(s, sizeof(*spriv));
if (!spriv)
return -ENOMEM;
spriv->iobase = iobase;
s->type = COMEDI_SUBD_TIMER;
s->subdev_flags = SDF_WRITABLE;
s->n_chan = 1;
s->maxdata = 0xff;
s->insn_config = addi_watchdog_insn_config;
s->insn_read = addi_watchdog_insn_read;
s->insn_write = addi_watchdog_insn_write;
return 0;
}
EXPORT_SYMBOL_GPL(addi_watchdog_init);
static int __init addi_watchdog_module_init(void)
{
return 0;
}
module_init(addi_watchdog_module_init);
static void __exit addi_watchdog_module_exit(void)
{
}
module_exit(addi_watchdog_module_exit);
MODULE_DESCRIPTION("ADDI-DATA Watchdog subdevice");
MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
MODULE_LICENSE("GPL");