diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-03-25 03:53:42 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-03-25 03:53:42 -0300 |
commit | 03dd4cb26d967f9588437b0fc9cc0e8353322bb7 (patch) | |
tree | fa581f6dc1c0596391690d1f67eceef3af8246dc /drivers/watchdog/watchdog_core.c | |
parent | d4e493caf788ef44982e131ff9c786546904d934 (diff) |
Linux-libre 4.5-gnu
Diffstat (limited to 'drivers/watchdog/watchdog_core.c')
-rw-r--r-- | drivers/watchdog/watchdog_core.c | 115 |
1 files changed, 84 insertions, 31 deletions
diff --git a/drivers/watchdog/watchdog_core.c b/drivers/watchdog/watchdog_core.c index 873f13972..e600fd93b 100644 --- a/drivers/watchdog/watchdog_core.c +++ b/drivers/watchdog/watchdog_core.c @@ -32,6 +32,7 @@ #include <linux/types.h> /* For standard types */ #include <linux/errno.h> /* For the -ENODEV/... values */ #include <linux/kernel.h> /* For printk/panic/... */ +#include <linux/reboot.h> /* For restart handler */ #include <linux/watchdog.h> /* For watchdog specific items */ #include <linux/init.h> /* For __init/__exit/... */ #include <linux/idr.h> /* For ida_* macros */ @@ -41,7 +42,6 @@ #include "watchdog_core.h" /* For watchdog_dev_register/... */ static DEFINE_IDA(watchdog_ida); -static struct class *watchdog_class; /* * Deferred Registration infrastructure. @@ -137,9 +137,63 @@ int watchdog_init_timeout(struct watchdog_device *wdd, } EXPORT_SYMBOL_GPL(watchdog_init_timeout); +static int watchdog_reboot_notifier(struct notifier_block *nb, + unsigned long code, void *data) +{ + struct watchdog_device *wdd = container_of(nb, struct watchdog_device, + reboot_nb); + + if (code == SYS_DOWN || code == SYS_HALT) { + if (watchdog_active(wdd)) { + int ret; + + ret = wdd->ops->stop(wdd); + if (ret) + return NOTIFY_BAD; + } + } + + return NOTIFY_DONE; +} + +static int watchdog_restart_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct watchdog_device *wdd = container_of(nb, struct watchdog_device, + restart_nb); + + int ret; + + ret = wdd->ops->restart(wdd); + if (ret) + return NOTIFY_BAD; + + return NOTIFY_DONE; +} + +/** + * watchdog_set_restart_priority - Change priority of restart handler + * @wdd: watchdog device + * @priority: priority of the restart handler, should follow these guidelines: + * 0: use watchdog's restart function as last resort, has limited restart + * capabilies + * 128: default restart handler, use if no other handler is expected to be + * available and/or if restart is sufficient to restart the entire system + * 255: preempt all other handlers + * + * If a wdd->ops->restart function is provided when watchdog_register_device is + * called, it will be registered as a restart handler with the priority given + * here. + */ +void watchdog_set_restart_priority(struct watchdog_device *wdd, int priority) +{ + wdd->restart_nb.priority = priority; +} +EXPORT_SYMBOL_GPL(watchdog_set_restart_priority); + static int __watchdog_register_device(struct watchdog_device *wdd) { - int ret, id = -1, devno; + int ret, id = -1; if (wdd == NULL || wdd->info == NULL || wdd->ops == NULL) return -EINVAL; @@ -156,8 +210,6 @@ static int __watchdog_register_device(struct watchdog_device *wdd) * corrupted in a later stage then we expect a kernel panic! */ - mutex_init(&wdd->lock); - /* Use alias for watchdog id if possible */ if (wdd->parent) { ret = of_alias_get_id(wdd->parent->of_node, "watchdog"); @@ -192,14 +244,26 @@ static int __watchdog_register_device(struct watchdog_device *wdd) } } - devno = wdd->cdev.dev; - wdd->dev = device_create(watchdog_class, wdd->parent, devno, - NULL, "watchdog%d", wdd->id); - if (IS_ERR(wdd->dev)) { - watchdog_dev_unregister(wdd); - ida_simple_remove(&watchdog_ida, id); - ret = PTR_ERR(wdd->dev); - return ret; + if (test_bit(WDOG_STOP_ON_REBOOT, &wdd->status)) { + wdd->reboot_nb.notifier_call = watchdog_reboot_notifier; + + ret = register_reboot_notifier(&wdd->reboot_nb); + if (ret) { + pr_err("watchdog%d: Cannot register reboot notifier (%d)\n", + wdd->id, ret); + watchdog_dev_unregister(wdd); + ida_simple_remove(&watchdog_ida, wdd->id); + return ret; + } + } + + if (wdd->ops->restart) { + wdd->restart_nb.notifier_call = watchdog_restart_notifier; + + ret = register_restart_handler(&wdd->restart_nb); + if (ret) + pr_warn("watchog%d: Cannot register restart handler (%d)\n", + wdd->id, ret); } return 0; @@ -232,19 +296,17 @@ EXPORT_SYMBOL_GPL(watchdog_register_device); static void __watchdog_unregister_device(struct watchdog_device *wdd) { - int ret; - int devno; - if (wdd == NULL) return; - devno = wdd->cdev.dev; - ret = watchdog_dev_unregister(wdd); - if (ret) - pr_err("error unregistering /dev/watchdog (err=%d)\n", ret); - device_destroy(watchdog_class, devno); + if (wdd->ops->restart) + unregister_restart_handler(&wdd->restart_nb); + + if (test_bit(WDOG_STOP_ON_REBOOT, &wdd->status)) + unregister_reboot_notifier(&wdd->reboot_nb); + + watchdog_dev_unregister(wdd); ida_simple_remove(&watchdog_ida, wdd->id); - wdd->dev = NULL; } /** @@ -287,17 +349,9 @@ static int __init watchdog_init(void) { int err; - watchdog_class = class_create(THIS_MODULE, "watchdog"); - if (IS_ERR(watchdog_class)) { - pr_err("couldn't create class\n"); - return PTR_ERR(watchdog_class); - } - err = watchdog_dev_init(); - if (err < 0) { - class_destroy(watchdog_class); + if (err < 0) return err; - } watchdog_deferred_registration(); return 0; @@ -306,7 +360,6 @@ static int __init watchdog_init(void) static void __exit watchdog_exit(void) { watchdog_dev_exit(); - class_destroy(watchdog_class); ida_destroy(&watchdog_ida); } |