[WATCHDOG 03/57] ali: watchdog locking and style

Clean up and check locking

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This commit is contained in:
Alan Cox 2008-05-19 14:04:57 +01:00 committed by Wim Van Sebroeck
parent b6b4d9b8d0
commit 173d95bc2e
2 changed files with 208 additions and 200 deletions

View file

@ -19,8 +19,8 @@
#include <linux/fs.h>
#include <linux/pci.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#define WATCHDOG_NAME "ALi_M1535"
#define PFX WATCHDOG_NAME ": "
@ -30,17 +30,21 @@
static unsigned long ali_is_open;
static char ali_expect_release;
static struct pci_dev *ali_pci;
static u32 ali_timeout_bits; /* stores the computed timeout */
static u32 ali_timeout_bits; /* stores the computed timeout */
static DEFINE_SPINLOCK(ali_lock); /* Guards the hardware */
/* module parameters */
static int timeout = WATCHDOG_TIMEOUT;
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (0<timeout<18000, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
MODULE_PARM_DESC(timeout,
"Watchdog timeout in seconds. (0 < timeout < 18000, default="
__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
static int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, int, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
/*
* ali_start - start watchdog countdown
@ -103,15 +107,16 @@ static void ali_keepalive(void)
static int ali_settimer(int t)
{
if(t < 0)
if (t < 0)
return -EINVAL;
else if(t < 60)
else if (t < 60)
ali_timeout_bits = t|(1<<6);
else if(t < 3600)
else if (t < 3600)
ali_timeout_bits = (t/60)|(1<<7);
else if(t < 18000)
else if (t < 18000)
ali_timeout_bits = (t/300)|(1<<6)|(1<<7);
else return -EINVAL;
else
return -EINVAL;
timeout = t;
return 0;
@ -134,21 +139,22 @@ static int ali_settimer(int t)
*/
static ssize_t ali_write(struct file *file, const char __user *data,
size_t len, loff_t * ppos)
size_t len, loff_t *ppos)
{
/* See if we got the magic character 'V' and reload the timer */
if (len) {
if (!nowayout) {
size_t i;
/* note: just in case someone wrote the magic character
* five months ago... */
/* note: just in case someone wrote the
magic character five months ago... */
ali_expect_release = 0;
/* scan to see whether or not we got the magic character */
/* scan to see whether or not we got
the magic character */
for (i = 0; i != len; i++) {
char c;
if(get_user(c, data+i))
if (get_user(c, data+i))
return -EFAULT;
if (c == 'V')
ali_expect_release = 42;
@ -163,7 +169,6 @@ static ssize_t ali_write(struct file *file, const char __user *data,
/*
* ali_ioctl - handle watchdog ioctls
* @inode: VFS inode
* @file: VFS file pointer
* @cmd: ioctl number
* @arg: arguments to the ioctl
@ -172,8 +177,7 @@ static ssize_t ali_write(struct file *file, const char __user *data,
* we want an extension to enable irq ack monitoring and the like
*/
static int ali_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
static long ali_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
void __user *argp = (void __user *)arg;
int __user *p = argp;
@ -186,57 +190,45 @@ static int ali_ioctl(struct inode *inode, struct file *file,
};
switch (cmd) {
case WDIOC_GETSUPPORT:
return copy_to_user(argp, &ident,
sizeof (ident)) ? -EFAULT : 0;
case WDIOC_GETSUPPORT:
return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
return put_user(0, p);
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
return put_user(0, p);
case WDIOC_KEEPALIVE:
ali_keepalive();
return 0;
case WDIOC_SETOPTIONS:
{
int new_options, retval = -EINVAL;
case WDIOC_KEEPALIVE:
ali_keepalive();
return 0;
case WDIOC_SETOPTIONS:
{
int new_options, retval = -EINVAL;
if (get_user (new_options, p))
return -EFAULT;
if (new_options & WDIOS_DISABLECARD) {
ali_stop();
retval = 0;
}
if (new_options & WDIOS_ENABLECARD) {
ali_start();
retval = 0;
}
return retval;
if (get_user(new_options, p))
return -EFAULT;
if (new_options & WDIOS_DISABLECARD) {
ali_stop();
retval = 0;
}
case WDIOC_SETTIMEOUT:
{
int new_timeout;
if (get_user(new_timeout, p))
return -EFAULT;
if (ali_settimer(new_timeout))
return -EINVAL;
ali_keepalive();
/* Fall */
if (new_options & WDIOS_ENABLECARD) {
ali_start();
retval = 0;
}
case WDIOC_GETTIMEOUT:
return put_user(timeout, p);
default:
return -ENOTTY;
return retval;
}
case WDIOC_SETTIMEOUT:
{
int new_timeout;
if (get_user(new_timeout, p))
return -EFAULT;
if (ali_settimer(new_timeout))
return -EINVAL;
ali_keepalive();
/* Fall */
}
case WDIOC_GETTIMEOUT:
return put_user(timeout, p);
default:
return -ENOTTY;
}
}
@ -274,10 +266,11 @@ static int ali_release(struct inode *inode, struct file *file)
/*
* Shut off the timer.
*/
if (ali_expect_release == 42) {
if (ali_expect_release == 42)
ali_stop();
} else {
printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
else {
printk(KERN_CRIT PFX
"Unexpected close, not stopping watchdog!\n");
ali_keepalive();
}
clear_bit(0, &ali_is_open);
@ -292,13 +285,11 @@ static int ali_release(struct inode *inode, struct file *file)
*/
static int ali_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
static int ali_notify_sys(struct notifier_block *this,
unsigned long code, void *unused)
{
if (code==SYS_DOWN || code==SYS_HALT) {
/* Turn the WDT off */
ali_stop();
}
if (code == SYS_DOWN || code == SYS_HALT)
ali_stop(); /* Turn the WDT off */
return NOTIFY_DONE;
}
@ -340,10 +331,10 @@ static int __init ali_find_watchdog(void)
/* Check for the a 7101 PMU */
pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x7101, NULL);
if(pdev == NULL)
if (pdev == NULL)
return -ENODEV;
if(pci_enable_device(pdev)) {
if (pci_enable_device(pdev)) {
pci_dev_put(pdev);
return -EIO;
}
@ -355,9 +346,12 @@ static int __init ali_find_watchdog(void)
*/
pci_read_config_dword(pdev, 0xCC, &wdog);
wdog &= ~0x3F; /* Timer bits */
wdog &= ~((1<<27)|(1<<26)|(1<<25)|(1<<24)); /* Issued events */
wdog &= ~((1<<16)|(1<<13)|(1<<12)|(1<<11)|(1<<10)|(1<<9)); /* No monitor bits */
/* Timer bits */
wdog &= ~0x3F;
/* Issued events */
wdog &= ~((1<<27)|(1<<26)|(1<<25)|(1<<24));
/* No monitor bits */
wdog &= ~((1<<16)|(1<<13)|(1<<12)|(1<<11)|(1<<10)|(1<<9));
pci_write_config_dword(pdev, 0xCC, wdog);
@ -369,12 +363,12 @@ static int __init ali_find_watchdog(void)
*/
static const struct file_operations ali_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = ali_write,
.ioctl = ali_ioctl,
.open = ali_open,
.release = ali_release,
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = ali_write,
.unlocked_ioctl = ali_ioctl,
.open = ali_open,
.release = ali_release,
};
static struct miscdevice ali_miscdev = {
@ -399,15 +393,16 @@ static int __init watchdog_init(void)
int ret;
/* Check whether or not the hardware watchdog is there */
if (ali_find_watchdog() != 0) {
if (ali_find_watchdog() != 0)
return -ENODEV;
}
/* Check that the timeout value is within it's range ; if not reset to the default */
/* Check that the timeout value is within it's range;
if not reset to the default */
if (timeout < 1 || timeout >= 18000) {
timeout = WATCHDOG_TIMEOUT;
printk(KERN_INFO PFX "timeout value must be 0<timeout<18000, using %d\n",
timeout);
printk(KERN_INFO PFX
"timeout value must be 0 < timeout < 18000, using %d\n",
timeout);
}
/* Calculate the watchdog's timeout */
@ -415,15 +410,16 @@ static int __init watchdog_init(void)
ret = register_reboot_notifier(&ali_notifier);
if (ret != 0) {
printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
ret);
printk(KERN_ERR PFX
"cannot register reboot notifier (err=%d)\n", ret);
goto out;
}
ret = misc_register(&ali_miscdev);
if (ret != 0) {
printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
WATCHDOG_MINOR, ret);
printk(KERN_ERR PFX
"cannot register miscdev on minor=%d (err=%d)\n",
WATCHDOG_MINOR, ret);
goto unreg_reboot;
}

View file

@ -32,8 +32,8 @@
#include <linux/fs.h>
#include <linux/pci.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <linux/io.h>
#include <linux/uaccess.h>
#include <asm/system.h>
#define OUR_NAME "alim7101_wdt"
@ -60,13 +60,17 @@
*/
#define WATCHDOG_TIMEOUT 30 /* 30 sec default timeout */
static int timeout = WATCHDOG_TIMEOUT; /* in seconds, will be multiplied by HZ to get seconds to wait for a ping */
/* in seconds, will be multiplied by HZ to get seconds to wait for a ping */
static int timeout = WATCHDOG_TIMEOUT;
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (1<=timeout<=3600, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
MODULE_PARM_DESC(timeout,
"Watchdog timeout in seconds. (1<=timeout<=3600, default="
__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
static int use_gpio = 0; /* Use the pic (for a1d revision alim7101) */
static int use_gpio; /* Use the pic (for a1d revision alim7101) */
module_param(use_gpio, int, 0);
MODULE_PARM_DESC(use_gpio, "Use the gpio watchdog. (required by old cobalt boards)");
MODULE_PARM_DESC(use_gpio,
"Use the gpio watchdog (required by old cobalt boards).");
static void wdt_timer_ping(unsigned long);
static DEFINE_TIMER(timer, wdt_timer_ping, 0, 1);
@ -77,8 +81,9 @@ static struct pci_dev *alim7101_pmu;
static int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, int, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
/*
* Whack the dog
@ -89,23 +94,26 @@ static void wdt_timer_ping(unsigned long data)
/* If we got a heartbeat pulse within the WDT_US_INTERVAL
* we agree to ping the WDT
*/
char tmp;
char tmp;
if(time_before(jiffies, next_heartbeat))
{
if (time_before(jiffies, next_heartbeat)) {
/* Ping the WDT (this is actually a disarm/arm sequence) */
pci_read_config_byte(alim7101_pmu, 0x92, &tmp);
pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, (tmp | ALI_WDT_ARM));
pci_write_config_byte(alim7101_pmu,
ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
pci_write_config_byte(alim7101_pmu,
ALI_7101_WDT, (tmp | ALI_WDT_ARM));
if (use_gpio) {
pci_read_config_byte(alim7101_pmu, ALI_7101_GPIO_O, &tmp);
pci_write_config_byte(alim7101_pmu, ALI_7101_GPIO_O, tmp
| 0x20);
pci_write_config_byte(alim7101_pmu, ALI_7101_GPIO_O, tmp
& ~0x20);
pci_read_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, &tmp);
pci_write_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, tmp | 0x20);
pci_write_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, tmp & ~0x20);
}
} else {
printk(KERN_WARNING PFX "Heartbeat lost! Will not ping the watchdog\n");
printk(KERN_WARNING PFX
"Heartbeat lost! Will not ping the watchdog\n");
}
/* Re-set the timer interval */
mod_timer(&timer, jiffies + WDT_INTERVAL);
@ -121,17 +129,23 @@ static void wdt_change(int writeval)
pci_read_config_byte(alim7101_pmu, ALI_7101_WDT, &tmp);
if (writeval == WDT_ENABLE) {
pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, (tmp | ALI_WDT_ARM));
pci_write_config_byte(alim7101_pmu,
ALI_7101_WDT, (tmp | ALI_WDT_ARM));
if (use_gpio) {
pci_read_config_byte(alim7101_pmu, ALI_7101_GPIO_O, &tmp);
pci_write_config_byte(alim7101_pmu, ALI_7101_GPIO_O, tmp & ~0x20);
pci_read_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, &tmp);
pci_write_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, tmp & ~0x20);
}
} else {
pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
pci_write_config_byte(alim7101_pmu,
ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
if (use_gpio) {
pci_read_config_byte(alim7101_pmu, ALI_7101_GPIO_O, &tmp);
pci_write_config_byte(alim7101_pmu, ALI_7101_GPIO_O, tmp | 0x20);
pci_read_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, &tmp);
pci_write_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, tmp | 0x20);
}
}
}
@ -169,10 +183,11 @@ static void wdt_keepalive(void)
* /dev/watchdog handling
*/
static ssize_t fop_write(struct file * file, const char __user * buf, size_t count, loff_t * ppos)
static ssize_t fop_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
/* See if we got the magic character 'V' and reload the timer */
if(count) {
if (count) {
if (!nowayout) {
size_t ofs;
@ -195,119 +210,116 @@ static ssize_t fop_write(struct file * file, const char __user * buf, size_t cou
return count;
}
static int fop_open(struct inode * inode, struct file * file)
static int fop_open(struct inode *inode, struct file *file)
{
/* Just in case we're already talking to someone... */
if(test_and_set_bit(0, &wdt_is_open))
if (test_and_set_bit(0, &wdt_is_open))
return -EBUSY;
/* Good, fire up the show */
wdt_startup();
return nonseekable_open(inode, file);
}
static int fop_close(struct inode * inode, struct file * file)
static int fop_close(struct inode *inode, struct file *file)
{
if(wdt_expect_close == 42)
if (wdt_expect_close == 42)
wdt_turnoff();
else {
/* wim: shouldn't there be a: del_timer(&timer); */
printk(KERN_CRIT PFX "device file closed unexpectedly. Will not stop the WDT!\n");
printk(KERN_CRIT PFX
"device file closed unexpectedly. Will not stop the WDT!\n");
}
clear_bit(0, &wdt_is_open);
wdt_expect_close = 0;
return 0;
}
static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
static long fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
void __user *argp = (void __user *)arg;
int __user *p = argp;
static struct watchdog_info ident =
{
.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
static struct watchdog_info ident = {
.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT
| WDIOF_MAGICCLOSE,
.firmware_version = 1,
.identity = "ALiM7101",
};
switch(cmd)
switch (cmd) {
case WDIOC_GETSUPPORT:
return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
return put_user(0, p);
case WDIOC_KEEPALIVE:
wdt_keepalive();
return 0;
case WDIOC_SETOPTIONS:
{
case WDIOC_GETSUPPORT:
return copy_to_user(argp, &ident, sizeof(ident))?-EFAULT:0;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
return put_user(0, p);
case WDIOC_KEEPALIVE:
wdt_keepalive();
return 0;
case WDIOC_SETOPTIONS:
{
int new_options, retval = -EINVAL;
int new_options, retval = -EINVAL;
if(get_user(new_options, p))
return -EFAULT;
if(new_options & WDIOS_DISABLECARD) {
wdt_turnoff();
retval = 0;
}
if(new_options & WDIOS_ENABLECARD) {
wdt_startup();
retval = 0;
}
return retval;
if (get_user(new_options, p))
return -EFAULT;
if (new_options & WDIOS_DISABLECARD) {
wdt_turnoff();
retval = 0;
}
case WDIOC_SETTIMEOUT:
{
int new_timeout;
if(get_user(new_timeout, p))
return -EFAULT;
if(new_timeout < 1 || new_timeout > 3600) /* arbitrary upper limit */
return -EINVAL;
timeout = new_timeout;
wdt_keepalive();
/* Fall through */
if (new_options & WDIOS_ENABLECARD) {
wdt_startup();
retval = 0;
}
case WDIOC_GETTIMEOUT:
return put_user(timeout, p);
default:
return -ENOTTY;
return retval;
}
case WDIOC_SETTIMEOUT:
{
int new_timeout;
if (get_user(new_timeout, p))
return -EFAULT;
/* arbitrary upper limit */
if (new_timeout < 1 || new_timeout > 3600)
return -EINVAL;
timeout = new_timeout;
wdt_keepalive();
/* Fall through */
}
case WDIOC_GETTIMEOUT:
return put_user(timeout, p);
default:
return -ENOTTY;
}
}
static const struct file_operations wdt_fops = {
.owner= THIS_MODULE,
.llseek= no_llseek,
.write= fop_write,
.open= fop_open,
.release= fop_close,
.ioctl= fop_ioctl,
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = fop_write,
.open = fop_open,
.release = fop_close,
.unlocked_ioctl = fop_ioctl,
};
static struct miscdevice wdt_miscdev = {
.minor=WATCHDOG_MINOR,
.name="watchdog",
.fops=&wdt_fops,
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &wdt_fops,
};
/*
* Notifier for system down
*/
static int wdt_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
static int wdt_notify_sys(struct notifier_block *this,
unsigned long code, void *unused)
{
if (code==SYS_DOWN || code==SYS_HALT)
if (code == SYS_DOWN || code == SYS_HALT)
wdt_turnoff();
if (code==SYS_RESTART) {
if (code == SYS_RESTART) {
/*
* Cobalt devices have no way of rebooting themselves other than
* getting the watchdog to pull reset, so we restart the watchdog on
* reboot with no heartbeat
* Cobalt devices have no way of rebooting themselves other
* than getting the watchdog to pull reset, so we restart the
* watchdog on reboot with no heartbeat
*/
wdt_change(WDT_ENABLE);
printk(KERN_INFO PFX "Watchdog timer is now enabled with no heartbeat - should reboot in ~1 second.\n");
@ -320,8 +332,7 @@ static int wdt_notify_sys(struct notifier_block *this, unsigned long code, void
* turn the timebomb registers off.
*/
static struct notifier_block wdt_notifier=
{
static struct notifier_block wdt_notifier = {
.notifier_call = wdt_notify_sys,
};
@ -354,7 +365,8 @@ static int __init alim7101_wdt_init(void)
ali1543_south = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533,
NULL);
if (!ali1543_south) {
printk(KERN_INFO PFX "ALi 1543 South-Bridge not present - WDT not set\n");
printk(KERN_INFO PFX
"ALi 1543 South-Bridge not present - WDT not set\n");
goto err_out;
}
pci_read_config_byte(ali1543_south, 0x5e, &tmp);
@ -363,24 +375,25 @@ static int __init alim7101_wdt_init(void)
if (!use_gpio) {
printk(KERN_INFO PFX "Detected old alim7101 revision 'a1d'. If this is a cobalt board, set the 'use_gpio' module parameter.\n");
goto err_out;
}
}
nowayout = 1;
} else if ((tmp & 0x1e) != 0x12 && (tmp & 0x1e) != 0x00) {
printk(KERN_INFO PFX "ALi 1543 South-Bridge does not have the correct revision number (???1001?) - WDT not set\n");
goto err_out;
}
if(timeout < 1 || timeout > 3600) /* arbitrary upper limit */
{
if (timeout < 1 || timeout > 3600) {
/* arbitrary upper limit */
timeout = WATCHDOG_TIMEOUT;
printk(KERN_INFO PFX "timeout value must be 1<=x<=3600, using %d\n",
timeout);
printk(KERN_INFO PFX
"timeout value must be 1 <= x <= 3600, using %d\n",
timeout);
}
rc = register_reboot_notifier(&wdt_notifier);
if (rc) {
printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
rc);
printk(KERN_ERR PFX
"cannot register reboot notifier (err=%d)\n", rc);
goto err_out;
}
@ -391,9 +404,8 @@ static int __init alim7101_wdt_init(void)
goto err_out_reboot;
}
if (nowayout) {
if (nowayout)
__module_get(THIS_MODULE);
}
printk(KERN_INFO PFX "WDT driver for ALi M7101 initialised. timeout=%d sec (nowayout=%d)\n",
timeout, nowayout);