From 32ecc6392654a0db34b310e8924b5b2c3b8bf503 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Fri, 25 Dec 2015 16:01:40 -0800 Subject: [PATCH] watchdog: Create watchdog device in watchdog_dev.c The watchdog character device is currently created in watchdog_dev.c, and the watchdog device in watchdog_core.c. This results in cross-dependencies, since device creation needs to know the watchdog character device number as well as the watchdog class, both of which reside in watchdog_dev.c. Create the watchdog device in watchdog_dev.c to simplify the code. Inspired by earlier patch set from Damien Riegel. Cc: Damien Riegel Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/watchdog_core.c | 33 +++------------ drivers/watchdog/watchdog_core.h | 4 +- drivers/watchdog/watchdog_dev.c | 73 ++++++++++++++++++++++++++------ 3 files changed, 69 insertions(+), 41 deletions(-) diff --git a/drivers/watchdog/watchdog_core.c b/drivers/watchdog/watchdog_core.c index 551af042867c..f0293f7d2b80 100644 --- a/drivers/watchdog/watchdog_core.c +++ b/drivers/watchdog/watchdog_core.c @@ -42,7 +42,6 @@ #include "watchdog_core.h" /* For watchdog_dev_register/... */ static DEFINE_IDA(watchdog_ida); -static struct class *watchdog_class; /* * Deferred Registration infrastructure. @@ -194,7 +193,7 @@ 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; @@ -247,16 +246,6 @@ static int __watchdog_register_device(struct watchdog_device *wdd) } } - devno = wdd->cdev.dev; - wdd->dev = device_create(watchdog_class, wdd->parent, devno, - wdd, "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; @@ -265,9 +254,7 @@ static int __watchdog_register_device(struct watchdog_device *wdd) dev_err(wdd->dev, "Cannot register reboot notifier (%d)\n", ret); watchdog_dev_unregister(wdd); - device_destroy(watchdog_class, devno); ida_simple_remove(&watchdog_ida, wdd->id); - wdd->dev = NULL; return ret; } } @@ -311,9 +298,6 @@ EXPORT_SYMBOL_GPL(watchdog_register_device); static void __watchdog_unregister_device(struct watchdog_device *wdd) { - int ret; - int devno; - if (wdd == NULL) return; @@ -323,13 +307,8 @@ static void __watchdog_unregister_device(struct watchdog_device *wdd) if (test_bit(WDOG_STOP_ON_REBOOT, &wdd->status)) unregister_reboot_notifier(&wdd->reboot_nb); - 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); + watchdog_dev_unregister(wdd); ida_simple_remove(&watchdog_ida, wdd->id); - wdd->dev = NULL; } /** @@ -370,9 +349,11 @@ static int __init watchdog_deferred_registration(void) static int __init watchdog_init(void) { - watchdog_class = watchdog_dev_init(); - if (IS_ERR(watchdog_class)) - return PTR_ERR(watchdog_class); + int err; + + err = watchdog_dev_init(); + if (err < 0) + return err; watchdog_deferred_registration(); return 0; diff --git a/drivers/watchdog/watchdog_core.h b/drivers/watchdog/watchdog_core.h index 1c8d6b0e68c7..86ff962d1e15 100644 --- a/drivers/watchdog/watchdog_core.h +++ b/drivers/watchdog/watchdog_core.h @@ -32,6 +32,6 @@ * Functions/procedures to be called by the core */ extern int watchdog_dev_register(struct watchdog_device *); -extern int watchdog_dev_unregister(struct watchdog_device *); -extern struct class * __init watchdog_dev_init(void); +extern void watchdog_dev_unregister(struct watchdog_device *); +extern int __init watchdog_dev_init(void); extern void __exit watchdog_dev_exit(void); diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c index f06fbcf0bea2..7ba3fc6157c7 100644 --- a/drivers/watchdog/watchdog_dev.c +++ b/drivers/watchdog/watchdog_dev.c @@ -628,17 +628,18 @@ static struct miscdevice watchdog_miscdev = { }; /* - * watchdog_dev_register: register a watchdog device + * watchdog_cdev_register: register watchdog character device * @wdd: watchdog device + * @devno: character device number * - * Register a watchdog device including handling the legacy + * Register a watchdog character device including handling the legacy * /dev/watchdog node. /dev/watchdog is actually a miscdevice and * thus we set it up like that. */ -int watchdog_dev_register(struct watchdog_device *wdd) +static int watchdog_cdev_register(struct watchdog_device *wdd, dev_t devno) { - int err, devno; + int err; if (wdd->id == 0) { old_wdd = wdd; @@ -656,7 +657,6 @@ int watchdog_dev_register(struct watchdog_device *wdd) } /* Fill in the data structures */ - devno = MKDEV(MAJOR(watchdog_devt), wdd->id); cdev_init(&wdd->cdev, &watchdog_fops); wdd->cdev.owner = wdd->ops->owner; @@ -674,13 +674,14 @@ int watchdog_dev_register(struct watchdog_device *wdd) } /* - * watchdog_dev_unregister: unregister a watchdog device + * watchdog_cdev_unregister: unregister watchdog character device * @watchdog: watchdog device * - * Unregister the watchdog and if needed the legacy /dev/watchdog device. + * Unregister watchdog character device and if needed the legacy + * /dev/watchdog device. */ -int watchdog_dev_unregister(struct watchdog_device *wdd) +static void watchdog_cdev_unregister(struct watchdog_device *wdd) { mutex_lock(&wdd->lock); set_bit(WDOG_UNREGISTERED, &wdd->status); @@ -691,7 +692,6 @@ int watchdog_dev_unregister(struct watchdog_device *wdd) misc_deregister(&watchdog_miscdev); old_wdd = NULL; } - return 0; } static struct class watchdog_class = { @@ -700,30 +700,77 @@ static struct class watchdog_class = { .dev_groups = wdt_groups, }; +/* + * watchdog_dev_register: register a watchdog device + * @wdd: watchdog device + * + * Register a watchdog device including handling the legacy + * /dev/watchdog node. /dev/watchdog is actually a miscdevice and + * thus we set it up like that. + */ + +int watchdog_dev_register(struct watchdog_device *wdd) +{ + struct device *dev; + dev_t devno; + int ret; + + devno = MKDEV(MAJOR(watchdog_devt), wdd->id); + + ret = watchdog_cdev_register(wdd, devno); + if (ret) + return ret; + + dev = device_create(&watchdog_class, wdd->parent, devno, wdd, + "watchdog%d", wdd->id); + if (IS_ERR(dev)) { + watchdog_cdev_unregister(wdd); + return PTR_ERR(dev); + } + wdd->dev = dev; + + return ret; +} + +/* + * watchdog_dev_unregister: unregister a watchdog device + * @watchdog: watchdog device + * + * Unregister watchdog device and if needed the legacy + * /dev/watchdog device. + */ + +void watchdog_dev_unregister(struct watchdog_device *wdd) +{ + watchdog_cdev_unregister(wdd); + device_destroy(&watchdog_class, wdd->dev->devt); + wdd->dev = NULL; +} + /* * watchdog_dev_init: init dev part of watchdog core * * Allocate a range of chardev nodes to use for watchdog devices */ -struct class * __init watchdog_dev_init(void) +int __init watchdog_dev_init(void) { int err; err = class_register(&watchdog_class); if (err < 0) { pr_err("couldn't register class\n"); - return ERR_PTR(err); + return err; } err = alloc_chrdev_region(&watchdog_devt, 0, MAX_DOGS, "watchdog"); if (err < 0) { pr_err("watchdog: unable to allocate char dev region\n"); class_unregister(&watchdog_class); - return ERR_PTR(err); + return err; } - return &watchdog_class; + return 0; } /* -- 2.20.1