Commit e73ae66c authored by Wim Van Sebroeck's avatar Wim Van Sebroeck

[WATCHDOG] wafer5823wdt.c - patch2

fix possible wafwdt_is_open race
make wdt_stop and wdt_start module params
change wd_margin to timeout and make it a module_param
make expect_close the same system as in advantechwdt.c
clean-up ioctl handling
added extra printk's to report what problem occured
add MODULE_DESCRIPTION info
parent 7a5aa432
...@@ -44,8 +44,8 @@ ...@@ -44,8 +44,8 @@
#define WD_TIMO 60 /* 60 sec default timeout */ #define WD_TIMO 60 /* 60 sec default timeout */
static unsigned long wafwdt_is_open; static unsigned long wafwdt_is_open;
static char expect_close;
static spinlock_t wafwdt_lock; static spinlock_t wafwdt_lock;
static int expect_close = 0;
/* /*
* You must set these - there is no sane way to probe for this board. * You must set these - there is no sane way to probe for this board.
...@@ -56,10 +56,17 @@ static int expect_close = 0; ...@@ -56,10 +56,17 @@ static int expect_close = 0;
* to restart it again. * to restart it again.
*/ */
#define WDT_START 0x443 static int wdt_stop = 0x843;
#define WDT_STOP 0x843 module_param(wdt_stop, int, 0);
MODULE_PARM_DESC(wdt_stop, "Wafer 5823 WDT 'stop' io port (default 0x843)");
static int wd_margin = WD_TIMO; static int wdt_start = 0x443;
module_param(wdt_start, int, 0);
MODULE_PARM_DESC(wdt_start, "Wafer 5823 WDT 'start' io port (default 0x443)");
static int timeout = WD_TIMO; /* in seconds */
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=255, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
#ifdef CONFIG_WATCHDOG_NOWAYOUT #ifdef CONFIG_WATCHDOG_NOWAYOUT
static int nowayout = 1; static int nowayout = 1;
...@@ -73,24 +80,24 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CON ...@@ -73,24 +80,24 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CON
static void wafwdt_ping(void) static void wafwdt_ping(void)
{ {
/* pat watchdog */ /* pat watchdog */
spin_lock(&wafwdt_lock); spin_lock(&wafwdt_lock);
inb_p(WDT_STOP); inb_p(wdt_stop);
inb_p(WDT_START); inb_p(wdt_start);
spin_unlock(&wafwdt_lock); spin_unlock(&wafwdt_lock);
} }
static void wafwdt_start(void) static void wafwdt_start(void)
{ {
/* start up watchdog */ /* start up watchdog */
outb_p(wd_margin, WDT_START); outb_p(timeout, wdt_start);
inb_p(WDT_START); inb_p(wdt_start);
} }
static void static void
wafwdt_stop(void) wafwdt_stop(void)
{ {
/* stop watchdog */ /* stop watchdog */
inb_p(WDT_STOP); inb_p(wdt_stop);
} }
static ssize_t wafwdt_write(struct file *file, const char *buf, size_t count, loff_t * ppos) static ssize_t wafwdt_write(struct file *file, const char *buf, size_t count, loff_t * ppos)
...@@ -99,6 +106,7 @@ static ssize_t wafwdt_write(struct file *file, const char *buf, size_t count, lo ...@@ -99,6 +106,7 @@ static ssize_t wafwdt_write(struct file *file, const char *buf, size_t count, lo
if (ppos != &file->f_pos) if (ppos != &file->f_pos)
return -ESPIPE; return -ESPIPE;
/* See if we got the magic character 'V' and reload the timer */
if (count) { if (count) {
if (!nowayout) { if (!nowayout) {
size_t i; size_t i;
...@@ -106,30 +114,30 @@ static ssize_t wafwdt_write(struct file *file, const char *buf, size_t count, lo ...@@ -106,30 +114,30 @@ static ssize_t wafwdt_write(struct file *file, const char *buf, size_t count, lo
/* In case it was set long ago */ /* In case it was set long ago */
expect_close = 0; expect_close = 0;
/* scan to see wether or not we got the magic character */
for (i = 0; i != count; i++) { for (i = 0; i != count; i++) {
char c; char c;
if (get_user(c, buf + i)) if (get_user(c, buf + i))
return -EFAULT; return -EFAULT;
if (c == 'V') if (c == 'V')
expect_close = 1; expect_close = 42;
} }
} }
/* Well, anyhow someone wrote to us, we should return that favour */
wafwdt_ping(); wafwdt_ping();
return 1;
} }
return 0; return count;
} }
static int wafwdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, static int wafwdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
unsigned long arg) unsigned long arg)
{ {
int new_margin; int new_timeout;
static struct watchdog_info ident = { static struct watchdog_info ident = {
.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
.firmware_version = 1, .firmware_version = 1,
.identity = "Wafer 5823 WDT", .identity = "Wafer 5823 WDT",
}; };
int one=1;
switch (cmd) { switch (cmd) {
case WDIOC_GETSUPPORT: case WDIOC_GETSUPPORT:
...@@ -139,25 +147,24 @@ static int wafwdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd ...@@ -139,25 +147,24 @@ static int wafwdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd
break; break;
case WDIOC_GETSTATUS: case WDIOC_GETSTATUS:
if (copy_to_user((int *) arg, &one, sizeof (int))) case WDIOC_GETBOOTSTATUS:
return -EFAULT; return put_user(0, (int *)arg);
break;
case WDIOC_KEEPALIVE: case WDIOC_KEEPALIVE:
wafwdt_ping(); wafwdt_ping();
break; break;
case WDIOC_SETTIMEOUT: case WDIOC_SETTIMEOUT:
if (get_user(new_margin, (int *)arg)) if (get_user(new_timeout, (int *)arg))
return -EFAULT; return -EFAULT;
if ((new_margin < 1) || (new_margin > 255)) if ((new_timeout < 1) || (new_timeout > 255))
return -EINVAL; return -EINVAL;
wd_margin = new_margin; timeout = new_timeout;
wafwdt_stop(); wafwdt_stop();
wafwdt_start(); wafwdt_start();
/* Fall */ /* Fall */
case WDIOC_GETTIMEOUT: case WDIOC_GETTIMEOUT:
return put_user(wd_margin, (int *)arg); return put_user(timeout, (int *)arg);
default: default:
return -ENOTTY; return -ENOTTY;
...@@ -169,6 +176,10 @@ static int wafwdt_open(struct inode *inode, struct file *file) ...@@ -169,6 +176,10 @@ static int wafwdt_open(struct inode *inode, struct file *file)
{ {
if (test_and_set_bit(0, &wafwdt_is_open)) if (test_and_set_bit(0, &wafwdt_is_open))
return -EBUSY; return -EBUSY;
/*
* Activate
*/
wafwdt_start(); wafwdt_start();
return 0; return 0;
} }
...@@ -176,12 +187,14 @@ static int wafwdt_open(struct inode *inode, struct file *file) ...@@ -176,12 +187,14 @@ static int wafwdt_open(struct inode *inode, struct file *file)
static int static int
wafwdt_close(struct inode *inode, struct file *file) wafwdt_close(struct inode *inode, struct file *file)
{ {
clear_bit(0, &wafwdt_is_open); if (expect_close == 42) {
if (expect_close) {
wafwdt_stop(); wafwdt_stop();
} else { } else {
printk(KERN_CRIT PFX "WDT device closed unexpectedly. WDT will not stop!\n"); printk(KERN_CRIT PFX "WDT device closed unexpectedly. WDT will not stop!\n");
wafwdt_ping();
} }
clear_bit(0, &wafwdt_is_open);
expect_close = 0;
return 0; return 0;
} }
...@@ -230,37 +243,77 @@ static struct notifier_block wafwdt_notifier = { ...@@ -230,37 +243,77 @@ static struct notifier_block wafwdt_notifier = {
static int __init wafwdt_init(void) static int __init wafwdt_init(void)
{ {
printk(KERN_INFO PFX "WDT driver for Wafer 5823 single board computer initialising.\n"); int ret;
printk(KERN_INFO "WDT driver for Wafer 5823 single board computer initialising.\n");
spin_lock_init(&wafwdt_lock); spin_lock_init(&wafwdt_lock);
if(!request_region(WDT_STOP, 1, "Wafer 5823 WDT"))
goto error; if (timeout < 1 || timeout > 63) {
if(!request_region(WDT_START, 1, "Wafer 5823 WDT")) timeout = WD_TIMO;
printk (KERN_INFO PFX "timeout value must be 1<=x<=255, using %d\n",
timeout);
}
if (wdt_stop != wdt_start) {
if(!request_region(wdt_stop, 1, "Wafer 5823 WDT")) {
printk (KERN_ERR PFX "I/O address 0x%04x already in use\n",
wdt_stop);
ret = -EIO;
goto error;
}
}
if(!request_region(wdt_start, 1, "Wafer 5823 WDT")) {
printk (KERN_ERR PFX "I/O address 0x%04x already in use\n",
wdt_start);
ret = -EIO;
goto error2; goto error2;
if(misc_register(&wafwdt_miscdev)<0) }
ret = register_reboot_notifier(&wafwdt_notifier);
if (ret != 0) {
printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
ret);
goto error3; goto error3;
register_reboot_notifier(&wafwdt_notifier); }
return 0;
ret = misc_register(&wafwdt_miscdev);
if (ret != 0) {
printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
WATCHDOG_MINOR, ret);
goto error4;
}
printk (KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n",
timeout, nowayout);
return ret;
error4:
unregister_reboot_notifier(&wafwdt_notifier);
error3: error3:
release_region(WDT_START, 1); release_region(wdt_start, 1);
error2: error2:
release_region(WDT_STOP, 1); if (wdt_stop != wdt_start)
release_region(wdt_stop, 1);
error: error:
return -ENODEV; return ret;
} }
static void __exit wafwdt_exit(void) static void __exit wafwdt_exit(void)
{ {
misc_deregister(&wafwdt_miscdev); misc_deregister(&wafwdt_miscdev);
unregister_reboot_notifier(&wafwdt_notifier); unregister_reboot_notifier(&wafwdt_notifier);
release_region(WDT_STOP, 1); if(wdt_stop != wdt_start)
release_region(WDT_START, 1); release_region(wdt_stop, 1);
release_region(wdt_start, 1);
} }
module_init(wafwdt_init); module_init(wafwdt_init);
module_exit(wafwdt_exit); module_exit(wafwdt_exit);
MODULE_AUTHOR("Justin Cormack"); MODULE_AUTHOR("Justin Cormack");
MODULE_DESCRIPTION("ICP Wafer 5823 Single Board Computer WDT driver");
MODULE_LICENSE("GPL"); MODULE_LICENSE("GPL");
/* end of wafer5823wdt.c */ /* end of wafer5823wdt.c */
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