From: Alan Cox Date: Mon, 19 May 2008 13:04:57 +0000 (+0100) Subject: [WATCHDOG 03/57] ali: watchdog locking and style X-Git-Tag: v2.6.27-rc3~81^2~13^2~54 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=173d95bc2e68baf73eb89fb9ef1cc63a66f581a5;p=linux-2.6-omap-h63xx.git [WATCHDOG 03/57] ali: watchdog locking and style Clean up and check locking Signed-off-by: Alan Cox Signed-off-by: Wim Van Sebroeck --- diff --git a/drivers/watchdog/alim1535_wdt.c b/drivers/watchdog/alim1535_wdt.c index 2b1fbdb2fcf..88760cb5ec1 100644 --- a/drivers/watchdog/alim1535_wdt.c +++ b/drivers/watchdog/alim1535_wdt.c @@ -19,8 +19,8 @@ #include #include -#include -#include +#include +#include #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= 18000) { timeout = WATCHDOG_TIMEOUT; - printk(KERN_INFO PFX "timeout value must be 0 #include -#include -#include +#include +#include #include #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; - - 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; - } + int new_options, retval = -EINVAL; - 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);