From fb551405c0f8e15d6fc7ae6e16a5e15382f8b8ac Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Tue, 22 May 2012 11:40:24 +0200 Subject: [PATCH] watchdog: sch56xx: Use watchdog core Convert sch56xx drivers to the generic watchdog core. Note this patch depends on the "watchdog: Add multiple device support" patch from Alan Cox. Signed-off-by: Hans de Goede Signed-off-by: Wim Van Sebroeck --- drivers/hwmon/sch5627.c | 2 +- drivers/hwmon/sch5636.c | 2 +- drivers/hwmon/sch56xx-common.c | 371 ++++++--------------------------- drivers/hwmon/sch56xx-common.h | 2 +- 4 files changed, 61 insertions(+), 316 deletions(-) diff --git a/drivers/hwmon/sch5627.c b/drivers/hwmon/sch5627.c index 8ec6dfbccb64..8342275378b8 100644 --- a/drivers/hwmon/sch5627.c +++ b/drivers/hwmon/sch5627.c @@ -579,7 +579,7 @@ static int __devinit sch5627_probe(struct platform_device *pdev) } /* Note failing to register the watchdog is not a fatal error */ - data->watchdog = sch56xx_watchdog_register(data->addr, + data->watchdog = sch56xx_watchdog_register(&pdev->dev, data->addr, (build_code << 24) | (build_id << 8) | hwmon_rev, &data->update_lock, 1); diff --git a/drivers/hwmon/sch5636.c b/drivers/hwmon/sch5636.c index 906d4ed32d81..96a7e68718ca 100644 --- a/drivers/hwmon/sch5636.c +++ b/drivers/hwmon/sch5636.c @@ -510,7 +510,7 @@ static int __devinit sch5636_probe(struct platform_device *pdev) } /* Note failing to register the watchdog is not a fatal error */ - data->watchdog = sch56xx_watchdog_register(data->addr, + data->watchdog = sch56xx_watchdog_register(&pdev->dev, data->addr, (revision[0] << 8) | revision[1], &data->update_lock, 0); diff --git a/drivers/hwmon/sch56xx-common.c b/drivers/hwmon/sch56xx-common.c index ce52fc57d41d..419a8e8f5191 100644 --- a/drivers/hwmon/sch56xx-common.c +++ b/drivers/hwmon/sch56xx-common.c @@ -66,15 +66,9 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" struct sch56xx_watchdog_data { u16 addr; - u32 revision; struct mutex *io_lock; - struct mutex watchdog_lock; - struct list_head list; /* member of the watchdog_data_list */ - struct kref kref; - struct miscdevice watchdog_miscdev; - unsigned long watchdog_is_open; - char watchdog_name[10]; /* must be unique to avoid sysfs conflict */ - char watchdog_expect_close; + struct watchdog_info wdinfo; + struct watchdog_device wddev; u8 watchdog_preset; u8 watchdog_control; u8 watchdog_output_enable; @@ -82,15 +76,6 @@ struct sch56xx_watchdog_data { static struct platform_device *sch56xx_pdev; -/* - * Somewhat ugly :( global data pointer list with all sch56xx devices, so that - * we can find our device data as when using misc_register there is no other - * method to get to ones device data from the open fop. - */ -static LIST_HEAD(watchdog_data_list); -/* Note this lock not only protect list access, but also data.kref access */ -static DEFINE_MUTEX(watchdog_data_mutex); - /* Super I/O functions */ static inline int superio_inb(int base, int reg) { @@ -272,22 +257,13 @@ EXPORT_SYMBOL(sch56xx_read_virtual_reg12); * Watchdog routines */ -/* - * Release our data struct when the platform device has been released *and* - * all references to our watchdog device are released. - */ -static void sch56xx_watchdog_release_resources(struct kref *r) -{ - struct sch56xx_watchdog_data *data = - container_of(r, struct sch56xx_watchdog_data, kref); - kfree(data); -} - -static int watchdog_set_timeout(struct sch56xx_watchdog_data *data, - int timeout) +static int watchdog_set_timeout(struct watchdog_device *wddev, + unsigned int timeout) { - int ret, resolution; + struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev); + unsigned int resolution; u8 control; + int ret; /* 1 second or 60 second resolution? */ if (timeout <= 255) @@ -298,12 +274,6 @@ static int watchdog_set_timeout(struct sch56xx_watchdog_data *data, if (timeout < resolution || timeout > (resolution * 255)) return -EINVAL; - mutex_lock(&data->watchdog_lock); - if (!data->addr) { - ret = -ENODEV; - goto leave; - } - if (resolution == 1) control = data->watchdog_control | SCH56XX_WDOG_TIME_BASE_SEC; else @@ -316,7 +286,7 @@ static int watchdog_set_timeout(struct sch56xx_watchdog_data *data, control); mutex_unlock(data->io_lock); if (ret) - goto leave; + return ret; data->watchdog_control = control; } @@ -326,38 +296,17 @@ static int watchdog_set_timeout(struct sch56xx_watchdog_data *data, * the watchdog countdown. */ data->watchdog_preset = DIV_ROUND_UP(timeout, resolution); + wddev->timeout = data->watchdog_preset * resolution; - ret = data->watchdog_preset * resolution; -leave: - mutex_unlock(&data->watchdog_lock); - return ret; -} - -static int watchdog_get_timeout(struct sch56xx_watchdog_data *data) -{ - int timeout; - - mutex_lock(&data->watchdog_lock); - if (data->watchdog_control & SCH56XX_WDOG_TIME_BASE_SEC) - timeout = data->watchdog_preset; - else - timeout = data->watchdog_preset * 60; - mutex_unlock(&data->watchdog_lock); - - return timeout; + return 0; } -static int watchdog_start(struct sch56xx_watchdog_data *data) +static int watchdog_start(struct watchdog_device *wddev) { + struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev); int ret; u8 val; - mutex_lock(&data->watchdog_lock); - if (!data->addr) { - ret = -ENODEV; - goto leave_unlock_watchdog; - } - /* * The sch56xx's watchdog cannot really be started / stopped * it is always running, but we can avoid the timer expiring @@ -405,39 +354,29 @@ static int watchdog_start(struct sch56xx_watchdog_data *data) leave: mutex_unlock(data->io_lock); -leave_unlock_watchdog: - mutex_unlock(&data->watchdog_lock); return ret; } -static int watchdog_trigger(struct sch56xx_watchdog_data *data) +static int watchdog_trigger(struct watchdog_device *wddev) { + struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev); int ret; - mutex_lock(&data->watchdog_lock); - if (!data->addr) { - ret = -ENODEV; - goto leave; - } - /* Reset the watchdog countdown counter */ mutex_lock(data->io_lock); ret = sch56xx_write_virtual_reg(data->addr, SCH56XX_REG_WDOG_PRESET, data->watchdog_preset); mutex_unlock(data->io_lock); -leave: - mutex_unlock(&data->watchdog_lock); + return ret; } -static int watchdog_stop_unlocked(struct sch56xx_watchdog_data *data) +static int watchdog_stop(struct watchdog_device *wddev) { + struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev); int ret = 0; u8 val; - if (!data->addr) - return -ENODEV; - if (data->watchdog_output_enable & SCH56XX_WDOG_OUTPUT_ENABLE) { val = data->watchdog_output_enable & ~SCH56XX_WDOG_OUTPUT_ENABLE; @@ -455,184 +394,19 @@ static int watchdog_stop_unlocked(struct sch56xx_watchdog_data *data) return ret; } -static int watchdog_stop(struct sch56xx_watchdog_data *data) -{ - int ret; - - mutex_lock(&data->watchdog_lock); - ret = watchdog_stop_unlocked(data); - mutex_unlock(&data->watchdog_lock); - - return ret; -} - -static int watchdog_release(struct inode *inode, struct file *filp) -{ - struct sch56xx_watchdog_data *data = filp->private_data; - - if (data->watchdog_expect_close) { - watchdog_stop(data); - data->watchdog_expect_close = 0; - } else { - watchdog_trigger(data); - pr_crit("unexpected close, not stopping watchdog!\n"); - } - - clear_bit(0, &data->watchdog_is_open); - - mutex_lock(&watchdog_data_mutex); - kref_put(&data->kref, sch56xx_watchdog_release_resources); - mutex_unlock(&watchdog_data_mutex); - - return 0; -} - -static int watchdog_open(struct inode *inode, struct file *filp) -{ - struct sch56xx_watchdog_data *pos, *data = NULL; - int ret, watchdog_is_open; - - /* - * We get called from drivers/char/misc.c with misc_mtx hold, and we - * call misc_register() from sch56xx_watchdog_probe() with - * watchdog_data_mutex hold, as misc_register() takes the misc_mtx - * lock, this is a possible deadlock, so we use mutex_trylock here. - */ - if (!mutex_trylock(&watchdog_data_mutex)) - return -ERESTARTSYS; - list_for_each_entry(pos, &watchdog_data_list, list) { - if (pos->watchdog_miscdev.minor == iminor(inode)) { - data = pos; - break; - } - } - /* Note we can never not have found data, so we don't check for this */ - watchdog_is_open = test_and_set_bit(0, &data->watchdog_is_open); - if (!watchdog_is_open) - kref_get(&data->kref); - mutex_unlock(&watchdog_data_mutex); - - if (watchdog_is_open) - return -EBUSY; - - filp->private_data = data; - - /* Start the watchdog */ - ret = watchdog_start(data); - if (ret) { - watchdog_release(inode, filp); - return ret; - } - - return nonseekable_open(inode, filp); -} - -static ssize_t watchdog_write(struct file *filp, const char __user *buf, - size_t count, loff_t *offset) -{ - int ret; - struct sch56xx_watchdog_data *data = filp->private_data; - - if (count) { - if (!nowayout) { - size_t i; - - /* Clear it in case it was set with a previous write */ - data->watchdog_expect_close = 0; - - for (i = 0; i != count; i++) { - char c; - if (get_user(c, buf + i)) - return -EFAULT; - if (c == 'V') - data->watchdog_expect_close = 1; - } - } - ret = watchdog_trigger(data); - if (ret) - return ret; - } - return count; -} - -static long watchdog_ioctl(struct file *filp, unsigned int cmd, - unsigned long arg) -{ - struct watchdog_info ident = { - .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT, - .identity = "sch56xx watchdog" - }; - int i, ret = 0; - struct sch56xx_watchdog_data *data = filp->private_data; - - switch (cmd) { - case WDIOC_GETSUPPORT: - ident.firmware_version = data->revision; - if (!nowayout) - ident.options |= WDIOF_MAGICCLOSE; - if (copy_to_user((void __user *)arg, &ident, sizeof(ident))) - ret = -EFAULT; - break; - - case WDIOC_GETSTATUS: - case WDIOC_GETBOOTSTATUS: - ret = put_user(0, (int __user *)arg); - break; - - case WDIOC_KEEPALIVE: - ret = watchdog_trigger(data); - break; - - case WDIOC_GETTIMEOUT: - i = watchdog_get_timeout(data); - ret = put_user(i, (int __user *)arg); - break; - - case WDIOC_SETTIMEOUT: - if (get_user(i, (int __user *)arg)) { - ret = -EFAULT; - break; - } - ret = watchdog_set_timeout(data, i); - if (ret >= 0) - ret = put_user(ret, (int __user *)arg); - break; - - case WDIOC_SETOPTIONS: - if (get_user(i, (int __user *)arg)) { - ret = -EFAULT; - break; - } - - if (i & WDIOS_DISABLECARD) - ret = watchdog_stop(data); - else if (i & WDIOS_ENABLECARD) - ret = watchdog_trigger(data); - else - ret = -EINVAL; - break; - - default: - ret = -ENOTTY; - } - return ret; -} - -static const struct file_operations watchdog_fops = { - .owner = THIS_MODULE, - .llseek = no_llseek, - .open = watchdog_open, - .release = watchdog_release, - .write = watchdog_write, - .unlocked_ioctl = watchdog_ioctl, +static const struct watchdog_ops watchdog_ops = { + .owner = THIS_MODULE, + .start = watchdog_start, + .stop = watchdog_stop, + .ping = watchdog_trigger, + .set_timeout = watchdog_set_timeout, }; -struct sch56xx_watchdog_data *sch56xx_watchdog_register( +struct sch56xx_watchdog_data *sch56xx_watchdog_register(struct device *parent, u16 addr, u32 revision, struct mutex *io_lock, int check_enabled) { struct sch56xx_watchdog_data *data; - int i, err, control, output_enable; - const int watchdog_minors[] = { WATCHDOG_MINOR, 212, 213, 214, 215 }; + int err, control, output_enable; /* Cache the watchdog registers */ mutex_lock(io_lock); @@ -656,82 +430,53 @@ struct sch56xx_watchdog_data *sch56xx_watchdog_register( return NULL; data->addr = addr; - data->revision = revision; data->io_lock = io_lock; - data->watchdog_control = control; - data->watchdog_output_enable = output_enable; - mutex_init(&data->watchdog_lock); - INIT_LIST_HEAD(&data->list); - kref_init(&data->kref); - - err = watchdog_set_timeout(data, 60); - if (err < 0) - goto error; - /* - * We take the data_mutex lock early so that watchdog_open() cannot - * run when misc_register() has completed, but we've not yet added - * our data to the watchdog_data_list. - */ - mutex_lock(&watchdog_data_mutex); - for (i = 0; i < ARRAY_SIZE(watchdog_minors); i++) { - /* Register our watchdog part */ - snprintf(data->watchdog_name, sizeof(data->watchdog_name), - "watchdog%c", (i == 0) ? '\0' : ('0' + i)); - data->watchdog_miscdev.name = data->watchdog_name; - data->watchdog_miscdev.fops = &watchdog_fops; - data->watchdog_miscdev.minor = watchdog_minors[i]; - err = misc_register(&data->watchdog_miscdev); - if (err == -EBUSY) - continue; - if (err) - break; + strlcpy(data->wdinfo.identity, "sch56xx watchdog", + sizeof(data->wdinfo.identity)); + data->wdinfo.firmware_version = revision; + data->wdinfo.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT; + if (!nowayout) + data->wdinfo.options |= WDIOF_MAGICCLOSE; + + data->wddev.info = &data->wdinfo; + data->wddev.ops = &watchdog_ops; + data->wddev.parent = parent; + data->wddev.timeout = 60; + data->wddev.min_timeout = 1; + data->wddev.max_timeout = 255 * 60; + if (nowayout) + data->wddev.status |= WDOG_NO_WAY_OUT; + if (output_enable & SCH56XX_WDOG_OUTPUT_ENABLE) + data->wddev.status |= WDOG_ACTIVE; + + /* Since the watchdog uses a downcounter there is no register to read + the BIOS set timeout from (if any was set at all) -> + Choose a preset which will give us a 1 minute timeout */ + if (control & SCH56XX_WDOG_TIME_BASE_SEC) + data->watchdog_preset = 60; /* seconds */ + else + data->watchdog_preset = 1; /* minute */ - list_add(&data->list, &watchdog_data_list); - pr_info("Registered /dev/%s chardev major 10, minor: %d\n", - data->watchdog_name, watchdog_minors[i]); - break; - } - mutex_unlock(&watchdog_data_mutex); + data->watchdog_control = control; + data->watchdog_output_enable = output_enable; + watchdog_set_drvdata(&data->wddev, data); + err = watchdog_register_device(&data->wddev); if (err) { pr_err("Registering watchdog chardev: %d\n", err); - goto error; - } - if (i == ARRAY_SIZE(watchdog_minors)) { - pr_warn("Couldn't register watchdog (no free minor)\n"); - goto error; + kfree(data); + return NULL; } return data; - -error: - kfree(data); - return NULL; } EXPORT_SYMBOL(sch56xx_watchdog_register); void sch56xx_watchdog_unregister(struct sch56xx_watchdog_data *data) { - mutex_lock(&watchdog_data_mutex); - misc_deregister(&data->watchdog_miscdev); - list_del(&data->list); - mutex_unlock(&watchdog_data_mutex); - - mutex_lock(&data->watchdog_lock); - if (data->watchdog_is_open) { - pr_warn("platform device unregistered with watchdog " - "open! Stopping watchdog.\n"); - watchdog_stop_unlocked(data); - } - /* Tell the wdog start/stop/trigger functions our dev is gone */ - data->addr = 0; - data->io_lock = NULL; - mutex_unlock(&data->watchdog_lock); - - mutex_lock(&watchdog_data_mutex); - kref_put(&data->kref, sch56xx_watchdog_release_resources); - mutex_unlock(&watchdog_data_mutex); + watchdog_unregister_device(&data->wddev); + kfree(data); } EXPORT_SYMBOL(sch56xx_watchdog_unregister); diff --git a/drivers/hwmon/sch56xx-common.h b/drivers/hwmon/sch56xx-common.h index 7475086eb978..704ea2c6d28a 100644 --- a/drivers/hwmon/sch56xx-common.h +++ b/drivers/hwmon/sch56xx-common.h @@ -27,6 +27,6 @@ int sch56xx_read_virtual_reg16(u16 addr, u16 reg); int sch56xx_read_virtual_reg12(u16 addr, u16 msb_reg, u16 lsn_reg, int high_nibble); -struct sch56xx_watchdog_data *sch56xx_watchdog_register( +struct sch56xx_watchdog_data *sch56xx_watchdog_register(struct device *parent, u16 addr, u32 revision, struct mutex *io_lock, int check_enabled); void sch56xx_watchdog_unregister(struct sch56xx_watchdog_data *data); -- 2.30.2