forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
340 lines
7.6 KiB
340 lines
7.6 KiB
// SPDX-License-Identifier: GPL-2.0+ |
|
/* |
|
* Advantech Single Board Computer WDT driver |
|
* |
|
* (c) Copyright 2000-2001 Marek Michalkiewicz <[email protected]> |
|
* |
|
* Based on acquirewdt.c which is based on wdt.c. |
|
* Original copyright messages: |
|
* |
|
* (c) Copyright 1996 Alan Cox <[email protected]>, |
|
* All Rights Reserved. |
|
* |
|
* Neither Alan Cox nor CymruNet Ltd. admit liability nor provide |
|
* warranty for any of this software. This material is provided |
|
* "AS-IS" and at no charge. |
|
* |
|
* (c) Copyright 1995 Alan Cox <[email protected]> |
|
* |
|
* 14-Dec-2001 Matt Domsch <[email protected]> |
|
* Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT |
|
* |
|
* 16-Oct-2002 Rob Radez <[email protected]> |
|
* Clean up ioctls, clean up init + exit, add expect close support, |
|
* add wdt_start and wdt_stop as parameters. |
|
*/ |
|
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
|
|
|
#include <linux/module.h> |
|
#include <linux/moduleparam.h> |
|
#include <linux/types.h> |
|
#include <linux/miscdevice.h> |
|
#include <linux/watchdog.h> |
|
#include <linux/fs.h> |
|
#include <linux/ioport.h> |
|
#include <linux/platform_device.h> |
|
#include <linux/init.h> |
|
#include <linux/io.h> |
|
#include <linux/uaccess.h> |
|
|
|
|
|
#define DRV_NAME "advantechwdt" |
|
#define WATCHDOG_NAME "Advantech WDT" |
|
#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */ |
|
|
|
/* the watchdog platform device */ |
|
static struct platform_device *advwdt_platform_device; |
|
static unsigned long advwdt_is_open; |
|
static char adv_expect_close; |
|
|
|
/* |
|
* You must set these - there is no sane way to probe for this board. |
|
* |
|
* To enable or restart, write the timeout value in seconds (1 to 63) |
|
* to I/O port wdt_start. To disable, read I/O port wdt_stop. |
|
* Both are 0x443 for most boards (tested on a PCA-6276VE-00B1), but |
|
* check your manual (at least the PCA-6159 seems to be different - |
|
* the manual says wdt_stop is 0x43, not 0x443). |
|
* (0x43 is also a write-only control register for the 8254 timer!) |
|
*/ |
|
|
|
static int wdt_stop = 0x443; |
|
module_param(wdt_stop, int, 0); |
|
MODULE_PARM_DESC(wdt_stop, "Advantech WDT 'stop' io port (default 0x443)"); |
|
|
|
static int wdt_start = 0x443; |
|
module_param(wdt_start, int, 0); |
|
MODULE_PARM_DESC(wdt_start, "Advantech WDT 'start' io port (default 0x443)"); |
|
|
|
static int timeout = WATCHDOG_TIMEOUT; /* in seconds */ |
|
module_param(timeout, int, 0); |
|
MODULE_PARM_DESC(timeout, |
|
"Watchdog timeout in seconds. 1<= timeout <=63, default=" |
|
__MODULE_STRING(WATCHDOG_TIMEOUT) "."); |
|
|
|
static bool nowayout = WATCHDOG_NOWAYOUT; |
|
module_param(nowayout, bool, 0); |
|
MODULE_PARM_DESC(nowayout, |
|
"Watchdog cannot be stopped once started (default=" |
|
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); |
|
|
|
/* |
|
* Watchdog Operations |
|
*/ |
|
|
|
static void advwdt_ping(void) |
|
{ |
|
/* Write a watchdog value */ |
|
outb_p(timeout, wdt_start); |
|
} |
|
|
|
static void advwdt_disable(void) |
|
{ |
|
inb_p(wdt_stop); |
|
} |
|
|
|
static int advwdt_set_heartbeat(int t) |
|
{ |
|
if (t < 1 || t > 63) |
|
return -EINVAL; |
|
timeout = t; |
|
return 0; |
|
} |
|
|
|
/* |
|
* /dev/watchdog handling |
|
*/ |
|
|
|
static ssize_t advwdt_write(struct file *file, const char __user *buf, |
|
size_t count, loff_t *ppos) |
|
{ |
|
if (count) { |
|
if (!nowayout) { |
|
size_t i; |
|
|
|
adv_expect_close = 0; |
|
|
|
for (i = 0; i != count; i++) { |
|
char c; |
|
if (get_user(c, buf + i)) |
|
return -EFAULT; |
|
if (c == 'V') |
|
adv_expect_close = 42; |
|
} |
|
} |
|
advwdt_ping(); |
|
} |
|
return count; |
|
} |
|
|
|
static long advwdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
|
{ |
|
int new_timeout; |
|
void __user *argp = (void __user *)arg; |
|
int __user *p = argp; |
|
static const struct watchdog_info ident = { |
|
.options = WDIOF_KEEPALIVEPING | |
|
WDIOF_SETTIMEOUT | |
|
WDIOF_MAGICCLOSE, |
|
.firmware_version = 1, |
|
.identity = WATCHDOG_NAME, |
|
}; |
|
|
|
switch (cmd) { |
|
case WDIOC_GETSUPPORT: |
|
if (copy_to_user(argp, &ident, sizeof(ident))) |
|
return -EFAULT; |
|
break; |
|
|
|
case WDIOC_GETSTATUS: |
|
case WDIOC_GETBOOTSTATUS: |
|
return put_user(0, p); |
|
|
|
case WDIOC_SETOPTIONS: |
|
{ |
|
int options, retval = -EINVAL; |
|
|
|
if (get_user(options, p)) |
|
return -EFAULT; |
|
if (options & WDIOS_DISABLECARD) { |
|
advwdt_disable(); |
|
retval = 0; |
|
} |
|
if (options & WDIOS_ENABLECARD) { |
|
advwdt_ping(); |
|
retval = 0; |
|
} |
|
return retval; |
|
} |
|
case WDIOC_KEEPALIVE: |
|
advwdt_ping(); |
|
break; |
|
|
|
case WDIOC_SETTIMEOUT: |
|
if (get_user(new_timeout, p)) |
|
return -EFAULT; |
|
if (advwdt_set_heartbeat(new_timeout)) |
|
return -EINVAL; |
|
advwdt_ping(); |
|
fallthrough; |
|
case WDIOC_GETTIMEOUT: |
|
return put_user(timeout, p); |
|
default: |
|
return -ENOTTY; |
|
} |
|
return 0; |
|
} |
|
|
|
static int advwdt_open(struct inode *inode, struct file *file) |
|
{ |
|
if (test_and_set_bit(0, &advwdt_is_open)) |
|
return -EBUSY; |
|
/* |
|
* Activate |
|
*/ |
|
|
|
advwdt_ping(); |
|
return stream_open(inode, file); |
|
} |
|
|
|
static int advwdt_close(struct inode *inode, struct file *file) |
|
{ |
|
if (adv_expect_close == 42) { |
|
advwdt_disable(); |
|
} else { |
|
pr_crit("Unexpected close, not stopping watchdog!\n"); |
|
advwdt_ping(); |
|
} |
|
clear_bit(0, &advwdt_is_open); |
|
adv_expect_close = 0; |
|
return 0; |
|
} |
|
|
|
/* |
|
* Kernel Interfaces |
|
*/ |
|
|
|
static const struct file_operations advwdt_fops = { |
|
.owner = THIS_MODULE, |
|
.llseek = no_llseek, |
|
.write = advwdt_write, |
|
.unlocked_ioctl = advwdt_ioctl, |
|
.compat_ioctl = compat_ptr_ioctl, |
|
.open = advwdt_open, |
|
.release = advwdt_close, |
|
}; |
|
|
|
static struct miscdevice advwdt_miscdev = { |
|
.minor = WATCHDOG_MINOR, |
|
.name = "watchdog", |
|
.fops = &advwdt_fops, |
|
}; |
|
|
|
/* |
|
* Init & exit routines |
|
*/ |
|
|
|
static int __init advwdt_probe(struct platform_device *dev) |
|
{ |
|
int ret; |
|
|
|
if (wdt_stop != wdt_start) { |
|
if (!request_region(wdt_stop, 1, WATCHDOG_NAME)) { |
|
pr_err("I/O address 0x%04x already in use\n", |
|
wdt_stop); |
|
ret = -EIO; |
|
goto out; |
|
} |
|
} |
|
|
|
if (!request_region(wdt_start, 1, WATCHDOG_NAME)) { |
|
pr_err("I/O address 0x%04x already in use\n", wdt_start); |
|
ret = -EIO; |
|
goto unreg_stop; |
|
} |
|
|
|
/* Check that the heartbeat value is within it's range ; |
|
* if not reset to the default */ |
|
if (advwdt_set_heartbeat(timeout)) { |
|
advwdt_set_heartbeat(WATCHDOG_TIMEOUT); |
|
pr_info("timeout value must be 1<=x<=63, using %d\n", timeout); |
|
} |
|
|
|
ret = misc_register(&advwdt_miscdev); |
|
if (ret != 0) { |
|
pr_err("cannot register miscdev on minor=%d (err=%d)\n", |
|
WATCHDOG_MINOR, ret); |
|
goto unreg_regions; |
|
} |
|
pr_info("initialized. timeout=%d sec (nowayout=%d)\n", |
|
timeout, nowayout); |
|
out: |
|
return ret; |
|
unreg_regions: |
|
release_region(wdt_start, 1); |
|
unreg_stop: |
|
if (wdt_stop != wdt_start) |
|
release_region(wdt_stop, 1); |
|
goto out; |
|
} |
|
|
|
static int advwdt_remove(struct platform_device *dev) |
|
{ |
|
misc_deregister(&advwdt_miscdev); |
|
release_region(wdt_start, 1); |
|
if (wdt_stop != wdt_start) |
|
release_region(wdt_stop, 1); |
|
|
|
return 0; |
|
} |
|
|
|
static void advwdt_shutdown(struct platform_device *dev) |
|
{ |
|
/* Turn the WDT off if we have a soft shutdown */ |
|
advwdt_disable(); |
|
} |
|
|
|
static struct platform_driver advwdt_driver = { |
|
.remove = advwdt_remove, |
|
.shutdown = advwdt_shutdown, |
|
.driver = { |
|
.name = DRV_NAME, |
|
}, |
|
}; |
|
|
|
static int __init advwdt_init(void) |
|
{ |
|
int err; |
|
|
|
pr_info("WDT driver for Advantech single board computer initialising\n"); |
|
|
|
advwdt_platform_device = platform_device_register_simple(DRV_NAME, |
|
-1, NULL, 0); |
|
if (IS_ERR(advwdt_platform_device)) |
|
return PTR_ERR(advwdt_platform_device); |
|
|
|
err = platform_driver_probe(&advwdt_driver, advwdt_probe); |
|
if (err) |
|
goto unreg_platform_device; |
|
|
|
return 0; |
|
|
|
unreg_platform_device: |
|
platform_device_unregister(advwdt_platform_device); |
|
return err; |
|
} |
|
|
|
static void __exit advwdt_exit(void) |
|
{ |
|
platform_device_unregister(advwdt_platform_device); |
|
platform_driver_unregister(&advwdt_driver); |
|
pr_info("Watchdog Module Unloaded\n"); |
|
} |
|
|
|
module_init(advwdt_init); |
|
module_exit(advwdt_exit); |
|
|
|
MODULE_LICENSE("GPL"); |
|
MODULE_AUTHOR("Marek Michalkiewicz <[email protected]>"); |
|
MODULE_DESCRIPTION("Advantech Single Board Computer WDT driver");
|
|
|