| Message ID | 20190730035050.15321-1-mbalant3@gmail.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | Revision of pc87413_wdt driver to use watchdog subsystem | expand |
On 7/29/19 8:50 PM, Mark Balantzyan wrote: > This patch rewrites the pc87413_wdt driver to use the watchdog subsystem. In > doing so, it also addresses a potential race condition owing from the > swc_base_addr variable being used before being set. > > Signed-off-by: Mark Balantzyan <mbalant3@gmail.com> > "Revision of ..." is an odd subject line. Also, please start the subject line with "watchdog: pc87413: ". > --- > drivers/watchdog/Kconfig | 1 + > drivers/watchdog/pc87413_wdt.c | 294 +++++---------------------------- > 2 files changed, 39 insertions(+), 256 deletions(-) > > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index 9af07fd9..84a7326d 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -1166,6 +1166,7 @@ config SCx200_WDT > > config PC87413_WDT > tristate "NS PC87413 watchdog" > + select WATCHDOG_CORE > depends on X86 > ---help--- > This is the driver for the hardware watchdog on the PC87413 chipset > diff --git a/drivers/watchdog/pc87413_wdt.c b/drivers/watchdog/pc87413_wdt.c > index 06a892e3..d1d32771 100644 > --- a/drivers/watchdog/pc87413_wdt.c > +++ b/drivers/watchdog/pc87413_wdt.c > @@ -22,12 +22,10 @@ > > #include <linux/module.h> > #include <linux/types.h> > -#include <linux/miscdevice.h> > #include <linux/watchdog.h> > #include <linux/ioport.h> > #include <linux/delay.h> Is this used anywhere ? > #include <linux/notifier.h> > -#include <linux/fs.h> > #include <linux/reboot.h> notifier.h and reboot.h should not be needed if the code is changed to use watchdog_stop_on_reboot(). > #include <linux/init.h> > #include <linux/spinlock.h> No longer needed. > @@ -65,7 +63,6 @@ static char expect_close; /* is the close expected? */ > > static DEFINE_SPINLOCK(io_lock); /* to guard us from io races */ > No longer needed. > -static bool nowayout = WATCHDOG_NOWAYOUT; > > /* -- Low level function ----------------------------------------*/ > > @@ -216,41 +213,32 @@ static inline void pc87413_disable_sw_wd_trg(void) > > /* -- Higher level functions ------------------------------------*/ > > -/* Enable the watchdog */ > +/* Enable/start the watchdog */ > > -static void pc87413_enable(void) > +static void pc87413_start(void) I am quite sure you still see a warning here, or rather where the function is referenced. > { > - spin_lock(&io_lock); > - > pc87413_swc_bank3(); > pc87413_programm_wdto(timeout); > pc87413_enable_wden(); > pc87413_enable_sw_wd_tren(); > pc87413_enable_sw_wd_trg(); > > - spin_unlock(&io_lock); > } > > -/* Disable the watchdog */ > +/* Disable/stop the watchdog */ > > -static void pc87413_disable(void) > +static void pc87413_stop(void) Same here. > { > - spin_lock(&io_lock); > - > pc87413_swc_bank3(); > pc87413_disable_sw_wd_tren(); > pc87413_disable_sw_wd_trg(); > pc87413_programm_wdto(0); > - > - spin_unlock(&io_lock); > } > > -/* Refresh the watchdog */ > +/* Refresh/keepalive the watchdog */ > > -static void pc87413_refresh(void) > +static void pc87413_keepalive(struct watchdog_device *wdd) > { > - spin_lock(&io_lock); > - > pc87413_swc_bank3(); > pc87413_disable_sw_wd_tren(); > pc87413_disable_sw_wd_trg(); > @@ -258,195 +246,11 @@ static void pc87413_refresh(void) > pc87413_enable_wden(); > pc87413_enable_sw_wd_tren(); > pc87413_enable_sw_wd_trg(); > - > - spin_unlock(&io_lock); > -} > - > -/* -- File operations -------------------------------------------*/ > - > -/** > - * pc87413_open: > - * @inode: inode of device > - * @file: file handle to device > - * > - */ > - > -static int pc87413_open(struct inode *inode, struct file *file) > -{ > - /* /dev/watchdog can only be opened once */ > - > - if (test_and_set_bit(0, &timer_enabled)) > - return -EBUSY; > - > - if (nowayout) > - __module_get(THIS_MODULE); > - > - /* Reload and activate timer */ > - pc87413_refresh(); > - > - pr_info("Watchdog enabled. Timeout set to %d minute(s).\n", timeout); > - > - return nonseekable_open(inode, file); > -} > - > -/** > - * pc87413_release: > - * @inode: inode to board > - * @file: file handle to board > - * > - * The watchdog has a configurable API. There is a religious dispute > - * between people who want their watchdog to be able to shut down and > - * those who want to be sure if the watchdog manager dies the machine > - * reboots. In the former case we disable the counters, in the latter > - * case you have to open it again very soon. > - */ > - > -static int pc87413_release(struct inode *inode, struct file *file) > -{ > - /* Shut off the timer. */ > - > - if (expect_close == 42) { > - pc87413_disable(); > - pr_info("Watchdog disabled, sleeping again...\n"); > - } else { > - pr_crit("Unexpected close, not stopping watchdog!\n"); > - pc87413_refresh(); > - } > - clear_bit(0, &timer_enabled); > - expect_close = 0; > return 0; > } > > -/** > - * pc87413_status: > - * > - * return, if the watchdog is enabled (timeout is set...) > - */ > - > - > -static int pc87413_status(void) > -{ > - return 0; /* currently not supported */ > -} > - > -/** > - * pc87413_write: > - * @file: file handle to the watchdog > - * @data: data buffer to write > - * @len: length in bytes > - * @ppos: pointer to the position to write. No seeks allowed > - * > - * A write to a watchdog device is defined as a keepalive signal. Any > - * write of data will do, as we we don't define content meaning. > - */ > - > -static ssize_t pc87413_write(struct file *file, const char __user *data, > - 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; > - > - /* reset expect flag */ > - expect_close = 0; > - > - /* 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)) > - return -EFAULT; > - if (c == 'V') > - expect_close = 42; > - } > - } > - > - /* someone wrote to us, we should reload the timer */ > - pc87413_refresh(); > - } > - return len; > -} > - > -/** > - * pc87413_ioctl: > - * @file: file handle to the device > - * @cmd: watchdog command > - * @arg: argument pointer > - * > - * The watchdog API defines a common set of functions for all watchdogs > - * according to their available features. We only actually usefully support > - * querying capabilities and current status. > - */ > - > -static long pc87413_ioctl(struct file *file, unsigned int cmd, > - unsigned long arg) > -{ > - int new_timeout; > - > - union { > - struct watchdog_info __user *ident; > - int __user *i; > - } uarg; > - > - static const struct watchdog_info ident = { > - .options = WDIOF_KEEPALIVEPING | > - WDIOF_SETTIMEOUT | > - WDIOF_MAGICCLOSE, > - .firmware_version = 1, > - .identity = "PC87413(HF/F) watchdog", > - }; > - > - uarg.i = (int __user *)arg; > - > - switch (cmd) { > - case WDIOC_GETSUPPORT: > - return copy_to_user(uarg.ident, &ident, > - sizeof(ident)) ? -EFAULT : 0; > - case WDIOC_GETSTATUS: > - return put_user(pc87413_status(), uarg.i); > - case WDIOC_GETBOOTSTATUS: > - return put_user(0, uarg.i); > - case WDIOC_SETOPTIONS: > - { > - int options, retval = -EINVAL; > - if (get_user(options, uarg.i)) > - return -EFAULT; > - if (options & WDIOS_DISABLECARD) { > - pc87413_disable(); > - retval = 0; > - } > - if (options & WDIOS_ENABLECARD) { > - pc87413_enable(); > - retval = 0; > - } > - return retval; > - } > - case WDIOC_KEEPALIVE: > - pc87413_refresh(); > -#ifdef DEBUG > - pr_info(DPFX "keepalive\n"); > -#endif > - return 0; > - case WDIOC_SETTIMEOUT: > - if (get_user(new_timeout, uarg.i)) > - return -EFAULT; > - /* the API states this is given in secs */ > - new_timeout /= 60; > - if (new_timeout < 0 || new_timeout > MAX_TIMEOUT) > - return -EINVAL; > - timeout = new_timeout; > - pc87413_refresh(); > - /* fall through and return the new timeout... */ > - case WDIOC_GETTIMEOUT: > - new_timeout = timeout * 60; > - return put_user(new_timeout, uarg.i); > - default: > - return -ENOTTY; > - } > -} > > -/* -- Notifier funtions -----------------------------------------*/ > +/* -- Notifier functions -----------------------------------------*/ > > /** > * notify_sys: > @@ -460,37 +264,43 @@ static long pc87413_ioctl(struct file *file, unsigned int cmd, > * trust me - if it happens it does suck. > */ > > -static int pc87413_notify_sys(struct notifier_block *this, > - unsigned long code, > - void *unused) > + > +/* -- Module's structures ---------------------------------------*/ > + > + > +static int watchdog_restart_notifier(struct notifier_block *nb, > + unsigned long code, void *data) > { > - if (code == SYS_DOWN || code == SYS_HALT) > - /* Turn the card off */ > - pc87413_disable(); > + struct watchdog_device *wdd = container_of(nb, struct watchdog_device, > + reboot_nb); > + > + if (code == SYS_DOWN || code == SYS_HALT) { > + int ret; > + > + ret = wdd->ops->stop(wdd); > + if (ret) > + return NOTIFY_BAD; > + } > + > return NOTIFY_DONE; > } > As mentioned, please drop the notifier function and call watchdog_stop_on_reboot() prior to registering the watchdog. > -/* -- Module's structures ---------------------------------------*/ > > -static const struct file_operations pc87413_fops = { > - .owner = THIS_MODULE, > - .llseek = no_llseek, > - .write = pc87413_write, > - .unlocked_ioctl = pc87413_ioctl, > - .open = pc87413_open, > - .release = pc87413_release, > -}; > > -static struct notifier_block pc87413_notifier = { > - .notifier_call = pc87413_notify_sys, > +static struct watchdog_ops pc87413wdt_ops = { > + .owner = THIS_MODULE, > + .start = pc87413_start, > + .stop = pc87413_stop, > + .ping = pc87413_keepalive, I don't immediately see how timeouts are now handled, and I am not sure if they are handled correctly, especially with the removed /* the API states this is given in secs */ new_timeout /= 60; above, and the datasheet says that timeouts are in multiples of minutes. This means that a set_)timeout function will be needed to calculate and set the correct timeout values. > + .restart = watchdog_restart_notifier, Bad alignment > }; > > -static struct miscdevice pc87413_miscdev = { > - .minor = WATCHDOG_MINOR, > - .name = "watchdog", > - .fops = &pc87413_fops, > +static struct watchdog_device pc87413wdt_wdd = { > + .ops = &pc87413wdt_ops, > + .status = WATCHDOG_NOWAYOUT_INIT_STATUS, > }; > > + > /* -- Module init functions -------------------------------------*/ > > /** > @@ -498,7 +308,6 @@ static struct miscdevice pc87413_miscdev = { > * > * Set up the WDT watchdog board. All we have to do is grab the > * resources we require and bitch if anyone beat us to them. > - * The open() function will actually kick the board off. > */ > > static int __init pc87413_init(void) > @@ -511,16 +320,7 @@ static int __init pc87413_init(void) > if (!request_muxed_region(io, 2, MODNAME)) > return -EBUSY; > > - ret = register_reboot_notifier(&pc87413_notifier); > - if (ret != 0) > - pr_err("cannot register reboot notifier (err=%d)\n", ret); > - > - ret = misc_register(&pc87413_miscdev); > - if (ret != 0) { > - pr_err("cannot register miscdev on minor=%d (err=%d)\n", > - WATCHDOG_MINOR, ret); > - goto reboot_unreg; > - } > + ret = watchdog_register_device(&pc87413wdt_wdd); > pr_info("initialized. timeout=%d min\n", timeout); > > pc87413_select_wdt_out(); > @@ -533,17 +333,12 @@ static int __init pc87413_init(void) > goto misc_unreg; > } > > - pc87413_enable(); > - > release_region(io, 2); > + pc87413_keepalive(&pc87413wdt_wdd); Not needed: The watchdog is not (or should not be) running. > return 0; > > misc_unreg: Wrong label name. > - misc_deregister(&pc87413_miscdev); > -reboot_unreg: > - unregister_reboot_notifier(&pc87413_notifier); > - release_region(io, 2); > - return ret; > + watchdog_unregister_device(&pc87413wdt_wdd); I am getting a bit lost here, but it seems to me this is called if watchdog registration failed. The cleanup is wrong. You still need to call release_region(), you don't need to unregister the watchdog, and you still need to return ret. > } > > /** > @@ -558,14 +353,7 @@ reboot_unreg: > > static void __exit pc87413_exit(void) > { > - /* Stop the timer before we leave */ > - if (!nowayout) { > - pc87413_disable(); > - pr_info("Watchdog disabled\n"); > - } > - > - misc_deregister(&pc87413_miscdev); > - unregister_reboot_notifier(&pc87413_notifier); > + watchdog_unregister_device(&pc87413wdt_wdd); > release_region(swc_base_addr, 0x20); > > pr_info("watchdog component driver removed\n"); > @@ -587,9 +375,3 @@ module_param(timeout, int, 0); > MODULE_PARM_DESC(timeout, > "Watchdog timeout in minutes (default=" > __MODULE_STRING(DEFAULT_TIMEOUT) ")."); > - > -module_param(nowayout, bool, 0); > -MODULE_PARM_DESC(nowayout, > - "Watchdog cannot be stopped once started (default=" > - __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); > - Again, why drop this module parameter ? >
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 9af07fd9..84a7326d 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1166,6 +1166,7 @@ config SCx200_WDT config PC87413_WDT tristate "NS PC87413 watchdog" + select WATCHDOG_CORE depends on X86 ---help--- This is the driver for the hardware watchdog on the PC87413 chipset diff --git a/drivers/watchdog/pc87413_wdt.c b/drivers/watchdog/pc87413_wdt.c index 06a892e3..d1d32771 100644 --- a/drivers/watchdog/pc87413_wdt.c +++ b/drivers/watchdog/pc87413_wdt.c @@ -22,12 +22,10 @@ #include <linux/module.h> #include <linux/types.h> -#include <linux/miscdevice.h> #include <linux/watchdog.h> #include <linux/ioport.h> #include <linux/delay.h> #include <linux/notifier.h> -#include <linux/fs.h> #include <linux/reboot.h> #include <linux/init.h> #include <linux/spinlock.h> @@ -65,7 +63,6 @@ static char expect_close; /* is the close expected? */ static DEFINE_SPINLOCK(io_lock); /* to guard us from io races */ -static bool nowayout = WATCHDOG_NOWAYOUT; /* -- Low level function ----------------------------------------*/ @@ -216,41 +213,32 @@ static inline void pc87413_disable_sw_wd_trg(void) /* -- Higher level functions ------------------------------------*/ -/* Enable the watchdog */ +/* Enable/start the watchdog */ -static void pc87413_enable(void) +static void pc87413_start(void) { - spin_lock(&io_lock); - pc87413_swc_bank3(); pc87413_programm_wdto(timeout); pc87413_enable_wden(); pc87413_enable_sw_wd_tren(); pc87413_enable_sw_wd_trg(); - spin_unlock(&io_lock); } -/* Disable the watchdog */ +/* Disable/stop the watchdog */ -static void pc87413_disable(void) +static void pc87413_stop(void) { - spin_lock(&io_lock); - pc87413_swc_bank3(); pc87413_disable_sw_wd_tren(); pc87413_disable_sw_wd_trg(); pc87413_programm_wdto(0); - - spin_unlock(&io_lock); } -/* Refresh the watchdog */ +/* Refresh/keepalive the watchdog */ -static void pc87413_refresh(void) +static void pc87413_keepalive(struct watchdog_device *wdd) { - spin_lock(&io_lock); - pc87413_swc_bank3(); pc87413_disable_sw_wd_tren(); pc87413_disable_sw_wd_trg(); @@ -258,195 +246,11 @@ static void pc87413_refresh(void) pc87413_enable_wden(); pc87413_enable_sw_wd_tren(); pc87413_enable_sw_wd_trg(); - - spin_unlock(&io_lock); -} - -/* -- File operations -------------------------------------------*/ - -/** - * pc87413_open: - * @inode: inode of device - * @file: file handle to device - * - */ - -static int pc87413_open(struct inode *inode, struct file *file) -{ - /* /dev/watchdog can only be opened once */ - - if (test_and_set_bit(0, &timer_enabled)) - return -EBUSY; - - if (nowayout) - __module_get(THIS_MODULE); - - /* Reload and activate timer */ - pc87413_refresh(); - - pr_info("Watchdog enabled. Timeout set to %d minute(s).\n", timeout); - - return nonseekable_open(inode, file); -} - -/** - * pc87413_release: - * @inode: inode to board - * @file: file handle to board - * - * The watchdog has a configurable API. There is a religious dispute - * between people who want their watchdog to be able to shut down and - * those who want to be sure if the watchdog manager dies the machine - * reboots. In the former case we disable the counters, in the latter - * case you have to open it again very soon. - */ - -static int pc87413_release(struct inode *inode, struct file *file) -{ - /* Shut off the timer. */ - - if (expect_close == 42) { - pc87413_disable(); - pr_info("Watchdog disabled, sleeping again...\n"); - } else { - pr_crit("Unexpected close, not stopping watchdog!\n"); - pc87413_refresh(); - } - clear_bit(0, &timer_enabled); - expect_close = 0; return 0; } -/** - * pc87413_status: - * - * return, if the watchdog is enabled (timeout is set...) - */ - - -static int pc87413_status(void) -{ - return 0; /* currently not supported */ -} - -/** - * pc87413_write: - * @file: file handle to the watchdog - * @data: data buffer to write - * @len: length in bytes - * @ppos: pointer to the position to write. No seeks allowed - * - * A write to a watchdog device is defined as a keepalive signal. Any - * write of data will do, as we we don't define content meaning. - */ - -static ssize_t pc87413_write(struct file *file, const char __user *data, - 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; - - /* reset expect flag */ - expect_close = 0; - - /* 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)) - return -EFAULT; - if (c == 'V') - expect_close = 42; - } - } - - /* someone wrote to us, we should reload the timer */ - pc87413_refresh(); - } - return len; -} - -/** - * pc87413_ioctl: - * @file: file handle to the device - * @cmd: watchdog command - * @arg: argument pointer - * - * The watchdog API defines a common set of functions for all watchdogs - * according to their available features. We only actually usefully support - * querying capabilities and current status. - */ - -static long pc87413_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) -{ - int new_timeout; - - union { - struct watchdog_info __user *ident; - int __user *i; - } uarg; - - static const struct watchdog_info ident = { - .options = WDIOF_KEEPALIVEPING | - WDIOF_SETTIMEOUT | - WDIOF_MAGICCLOSE, - .firmware_version = 1, - .identity = "PC87413(HF/F) watchdog", - }; - - uarg.i = (int __user *)arg; - - switch (cmd) { - case WDIOC_GETSUPPORT: - return copy_to_user(uarg.ident, &ident, - sizeof(ident)) ? -EFAULT : 0; - case WDIOC_GETSTATUS: - return put_user(pc87413_status(), uarg.i); - case WDIOC_GETBOOTSTATUS: - return put_user(0, uarg.i); - case WDIOC_SETOPTIONS: - { - int options, retval = -EINVAL; - if (get_user(options, uarg.i)) - return -EFAULT; - if (options & WDIOS_DISABLECARD) { - pc87413_disable(); - retval = 0; - } - if (options & WDIOS_ENABLECARD) { - pc87413_enable(); - retval = 0; - } - return retval; - } - case WDIOC_KEEPALIVE: - pc87413_refresh(); -#ifdef DEBUG - pr_info(DPFX "keepalive\n"); -#endif - return 0; - case WDIOC_SETTIMEOUT: - if (get_user(new_timeout, uarg.i)) - return -EFAULT; - /* the API states this is given in secs */ - new_timeout /= 60; - if (new_timeout < 0 || new_timeout > MAX_TIMEOUT) - return -EINVAL; - timeout = new_timeout; - pc87413_refresh(); - /* fall through and return the new timeout... */ - case WDIOC_GETTIMEOUT: - new_timeout = timeout * 60; - return put_user(new_timeout, uarg.i); - default: - return -ENOTTY; - } -} -/* -- Notifier funtions -----------------------------------------*/ +/* -- Notifier functions -----------------------------------------*/ /** * notify_sys: @@ -460,37 +264,43 @@ static long pc87413_ioctl(struct file *file, unsigned int cmd, * trust me - if it happens it does suck. */ -static int pc87413_notify_sys(struct notifier_block *this, - unsigned long code, - void *unused) + +/* -- Module's structures ---------------------------------------*/ + + +static int watchdog_restart_notifier(struct notifier_block *nb, + unsigned long code, void *data) { - if (code == SYS_DOWN || code == SYS_HALT) - /* Turn the card off */ - pc87413_disable(); + struct watchdog_device *wdd = container_of(nb, struct watchdog_device, + reboot_nb); + + if (code == SYS_DOWN || code == SYS_HALT) { + int ret; + + ret = wdd->ops->stop(wdd); + if (ret) + return NOTIFY_BAD; + } + return NOTIFY_DONE; } -/* -- Module's structures ---------------------------------------*/ -static const struct file_operations pc87413_fops = { - .owner = THIS_MODULE, - .llseek = no_llseek, - .write = pc87413_write, - .unlocked_ioctl = pc87413_ioctl, - .open = pc87413_open, - .release = pc87413_release, -}; -static struct notifier_block pc87413_notifier = { - .notifier_call = pc87413_notify_sys, +static struct watchdog_ops pc87413wdt_ops = { + .owner = THIS_MODULE, + .start = pc87413_start, + .stop = pc87413_stop, + .ping = pc87413_keepalive, + .restart = watchdog_restart_notifier, }; -static struct miscdevice pc87413_miscdev = { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &pc87413_fops, +static struct watchdog_device pc87413wdt_wdd = { + .ops = &pc87413wdt_ops, + .status = WATCHDOG_NOWAYOUT_INIT_STATUS, }; + /* -- Module init functions -------------------------------------*/ /** @@ -498,7 +308,6 @@ static struct miscdevice pc87413_miscdev = { * * Set up the WDT watchdog board. All we have to do is grab the * resources we require and bitch if anyone beat us to them. - * The open() function will actually kick the board off. */ static int __init pc87413_init(void) @@ -511,16 +320,7 @@ static int __init pc87413_init(void) if (!request_muxed_region(io, 2, MODNAME)) return -EBUSY; - ret = register_reboot_notifier(&pc87413_notifier); - if (ret != 0) - pr_err("cannot register reboot notifier (err=%d)\n", ret); - - ret = misc_register(&pc87413_miscdev); - if (ret != 0) { - pr_err("cannot register miscdev on minor=%d (err=%d)\n", - WATCHDOG_MINOR, ret); - goto reboot_unreg; - } + ret = watchdog_register_device(&pc87413wdt_wdd); pr_info("initialized. timeout=%d min\n", timeout); pc87413_select_wdt_out(); @@ -533,17 +333,12 @@ static int __init pc87413_init(void) goto misc_unreg; } - pc87413_enable(); - release_region(io, 2); + pc87413_keepalive(&pc87413wdt_wdd); return 0; misc_unreg: - misc_deregister(&pc87413_miscdev); -reboot_unreg: - unregister_reboot_notifier(&pc87413_notifier); - release_region(io, 2); - return ret; + watchdog_unregister_device(&pc87413wdt_wdd); } /** @@ -558,14 +353,7 @@ reboot_unreg: static void __exit pc87413_exit(void) { - /* Stop the timer before we leave */ - if (!nowayout) { - pc87413_disable(); - pr_info("Watchdog disabled\n"); - } - - misc_deregister(&pc87413_miscdev); - unregister_reboot_notifier(&pc87413_notifier); + watchdog_unregister_device(&pc87413wdt_wdd); release_region(swc_base_addr, 0x20); pr_info("watchdog component driver removed\n"); @@ -587,9 +375,3 @@ module_param(timeout, int, 0); MODULE_PARM_DESC(timeout, "Watchdog timeout in minutes (default=" __MODULE_STRING(DEFAULT_TIMEOUT) ")."); - -module_param(nowayout, bool, 0); -MODULE_PARM_DESC(nowayout, - "Watchdog cannot be stopped once started (default=" - __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); -
This patch rewrites the pc87413_wdt driver to use the watchdog subsystem. In doing so, it also addresses a potential race condition owing from the swc_base_addr variable being used before being set. Signed-off-by: Mark Balantzyan <mbalant3@gmail.com> --- drivers/watchdog/Kconfig | 1 + drivers/watchdog/pc87413_wdt.c | 294 +++++---------------------------- 2 files changed, 39 insertions(+), 256 deletions(-)