diff options
Diffstat (limited to 'drivers/watchdog')
| -rw-r--r-- | drivers/watchdog/Kconfig | 1 | ||||
| -rw-r--r-- | drivers/watchdog/shwdt.c | 306 |
2 files changed, 94 insertions, 213 deletions
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index eeea76f4dccb..edebaf771f50 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1138,6 +1138,7 @@ config ZVM_WATCHDOG config SH_WDT tristate "SuperH Watchdog" depends on SUPERH && (CPU_SH3 || CPU_SH4) + select WATCHDOG_CORE help This driver adds watchdog support for the integrated watchdog in the SuperH processors. If you have one of these processors and wish diff --git a/drivers/watchdog/shwdt.c b/drivers/watchdog/shwdt.c index 93958a7763e6..e5b59bebcdb1 100644 --- a/drivers/watchdog/shwdt.c +++ b/drivers/watchdog/shwdt.c @@ -3,7 +3,7 @@ * * Watchdog driver for integrated watchdog in the SuperH processors. * - * Copyright (C) 2001 - 2010 Paul Mundt <lethal@linux-sh.org> + * Copyright (C) 2001 - 2012 Paul Mundt <lethal@linux-sh.org> * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the @@ -25,16 +25,15 @@ #include <linux/platform_device.h> #include <linux/init.h> #include <linux/types.h> +#include <linux/spinlock.h> #include <linux/miscdevice.h> #include <linux/watchdog.h> -#include <linux/reboot.h> -#include <linux/notifier.h> -#include <linux/ioport.h> +#include <linux/pm_runtime.h> #include <linux/fs.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/io.h> -#include <linux/uaccess.h> +#include <linux/clk.h> #include <asm/watchdog.h> #define DRV_NAME "sh-wdt" @@ -69,10 +68,6 @@ static int clock_division_ratio = WTCSR_CKS_4096; #define next_ping_period(cks) (jiffies + msecs_to_jiffies(cks - 4)) -static const struct watchdog_info sh_wdt_info; -static struct platform_device *sh_wdt_dev; -static DEFINE_SPINLOCK(shwdt_lock); - #define WATCHDOG_HEARTBEAT 30 /* 30 sec default heartbeat */ static int heartbeat = WATCHDOG_HEARTBEAT; /* in seconds */ static bool nowayout = WATCHDOG_NOWAYOUT; @@ -81,19 +76,22 @@ static unsigned long next_heartbeat; struct sh_wdt { void __iomem *base; struct device *dev; + struct clk *clk; + spinlock_t lock; struct timer_list timer; - - unsigned long enabled; - char expect_close; }; -static void sh_wdt_start(struct sh_wdt *wdt) +static int sh_wdt_start(struct watchdog_device *wdt_dev) { + struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev); unsigned long flags; u8 csr; - spin_lock_irqsave(&shwdt_lock, flags); + pm_runtime_get_sync(wdt->dev); + clk_enable(wdt->clk); + + spin_lock_irqsave(&wdt->lock, flags); next_heartbeat = jiffies + (heartbeat * HZ); mod_timer(&wdt->timer, next_ping_period(clock_division_ratio)); @@ -122,15 +120,18 @@ static void sh_wdt_start(struct sh_wdt *wdt) csr &= ~RSTCSR_RSTS; sh_wdt_write_rstcsr(csr); #endif - spin_unlock_irqrestore(&shwdt_lock, flags); + spin_unlock_irqrestore(&wdt->lock, flags); + + return 0; } -static void sh_wdt_stop(struct sh_wdt *wdt) +static int sh_wdt_stop(struct watchdog_device *wdt_dev) { + struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev); unsigned long flags; u8 csr; - spin_lock_irqsave(&shwdt_lock, flags); + spin_lock_irqsave(&wdt->lock, flags); del_timer(&wdt->timer); @@ -138,28 +139,39 @@ static void sh_wdt_stop(struct sh_wdt *wdt) csr &= ~WTCSR_TME; sh_wdt_write_csr(csr); - spin_unlock_irqrestore(&shwdt_lock, flags); + spin_unlock_irqrestore(&wdt->lock, flags); + + clk_disable(wdt->clk); + pm_runtime_put_sync(wdt->dev); + + return 0; } -static inline void sh_wdt_keepalive(struct sh_wdt *wdt) +static int sh_wdt_keepalive(struct watchdog_device *wdt_dev) { + struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev); unsigned long flags; - spin_lock_irqsave(&shwdt_lock, flags); + spin_lock_irqsave(&wdt->lock, flags); next_heartbeat = jiffies + (heartbeat * HZ); - spin_unlock_irqrestore(&shwdt_lock, flags); + spin_unlock_irqrestore(&wdt->lock, flags); + + return 0; } -static int sh_wdt_set_heartbeat(int t) +static int sh_wdt_set_heartbeat(struct watchdog_device *wdt_dev, unsigned t) { + struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev); unsigned long flags; if (unlikely(t < 1 || t > 3600)) /* arbitrary upper limit */ return -EINVAL; - spin_lock_irqsave(&shwdt_lock, flags); + spin_lock_irqsave(&wdt->lock, flags); heartbeat = t; - spin_unlock_irqrestore(&shwdt_lock, flags); + wdt_dev->timeout = t; + spin_unlock_irqrestore(&wdt->lock, flags); + return 0; } @@ -168,7 +180,7 @@ static void sh_wdt_ping(unsigned long data) struct sh_wdt *wdt = (struct sh_wdt *)data; unsigned long flags; - spin_lock_irqsave(&shwdt_lock, flags); + spin_lock_irqsave(&wdt->lock, flags); if (time_before(jiffies, next_heartbeat)) { u8 csr; @@ -182,137 +194,9 @@ static void sh_wdt_ping(unsigned long data) } else dev_warn(wdt->dev, "Heartbeat lost! Will not ping " "the watchdog\n"); - spin_unlock_irqrestore(&shwdt_lock, flags); -} - -static int sh_wdt_open(struct inode *inode, struct file *file) -{ - struct sh_wdt *wdt = platform_get_drvdata(sh_wdt_dev); - - if (test_and_set_bit(0, &wdt->enabled)) - return -EBUSY; - if (nowayout) - __module_get(THIS_MODULE); - - file->private_data = wdt; - - sh_wdt_start(wdt); - - return nonseekable_open(inode, file); -} - -static int sh_wdt_close(struct inode *inode, struct file *file) -{ - struct sh_wdt *wdt = file->private_data; - - if (wdt->expect_close == 42) { - sh_wdt_stop(wdt); - } else { - dev_crit(wdt->dev, "Unexpected close, not " - "stopping watchdog!\n"); - sh_wdt_keepalive(wdt); - } - - clear_bit(0, &wdt->enabled); - wdt->expect_close = 0; - - return 0; -} - -static ssize_t sh_wdt_write(struct file *file, const char *buf, - size_t count, loff_t *ppos) -{ - struct sh_wdt *wdt = file->private_data; - - if (count) { - if (!nowayout) { - size_t i; - - wdt->expect_close = 0; - - for (i = 0; i != count; i++) { - char c; - if (get_user(c, buf + i)) - return -EFAULT; - if (c == 'V') - wdt->expect_close = 42; - } - } - sh_wdt_keepalive(wdt); - } - - return count; + spin_unlock_irqrestore(&wdt->lock, flags); } -static long sh_wdt_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) -{ - struct sh_wdt *wdt = file->private_data; - int new_heartbeat; - int options, retval = -EINVAL; - - switch (cmd) { - case WDIOC_GETSUPPORT: - return copy_to_user((struct watchdog_info *)arg, - &sh_wdt_info, sizeof(sh_wdt_info)) ? -EFAULT : 0; - case WDIOC_GETSTATUS: - case WDIOC_GETBOOTSTATUS: - return put_user(0, (int *)arg); - case WDIOC_SETOPTIONS: - if (get_user(options, (int *)arg)) - return -EFAULT; - - if (options & WDIOS_DISABLECARD) { - sh_wdt_stop(wdt); - retval = 0; - } - - if (options & WDIOS_ENABLECARD) { - sh_wdt_start(wdt); - retval = 0; - } - - return retval; - case WDIOC_KEEPALIVE: - sh_wdt_keepalive(wdt); - return 0; - case WDIOC_SETTIMEOUT: - if (get_user(new_heartbeat, (int *)arg)) - return -EFAULT; - - if (sh_wdt_set_heartbeat(new_heartbeat)) - return -EINVAL; - - sh_wdt_keepalive(wdt); - /* Fall */ - case WDIOC_GETTIMEOUT: - return put_user(heartbeat, (int *)arg); - default: - return -ENOTTY; - } - return 0; -} - -static int sh_wdt_notify_sys(struct notifier_block *this, - unsigned long code, void *unused) -{ - struct sh_wdt *wdt = platform_get_drvdata(sh_wdt_dev); - - if (code == SYS_DOWN || code == SYS_HALT) - sh_wdt_stop(wdt); - - return NOTIFY_DONE; -} - -static const struct file_operations sh_wdt_fops = { - .owner = THIS_MODULE, - .llseek = no_llseek, - .write = sh_wdt_write, - .unlocked_ioctl = sh_wdt_ioctl, - .open = sh_wdt_open, - .release = sh_wdt_close, -}; - static const struct watchdog_info sh_wdt_info = { .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, @@ -320,14 +204,17 @@ static const struct watchdog_info sh_wdt_info = { .identity = "SH WDT", }; -static struct notifier_block sh_wdt_notifier = { - .notifier_call = sh_wdt_notify_sys, +static const struct watchdog_ops sh_wdt_ops = { + .owner = THIS_MODULE, + .start = sh_wdt_start, + .stop = sh_wdt_stop, + .ping = sh_wdt_keepalive, + .set_timeout = sh_wdt_set_heartbeat, }; -static struct miscdevice sh_wdt_miscdev = { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &sh_wdt_fops, +static struct watchdog_device sh_wdt_dev = { + .info = &sh_wdt_info, + .ops = &sh_wdt_ops, }; static int __devinit sh_wdt_probe(struct platform_device *pdev) @@ -347,39 +234,49 @@ static int __devinit sh_wdt_probe(struct platform_device *pdev) if (unlikely(!res)) return -EINVAL; - if (!devm_request_mem_region(&pdev->dev, res->start, - resource_size(res), DRV_NAME)) - return -EBUSY; - wdt = devm_kzalloc(&pdev->dev, sizeof(struct sh_wdt), GFP_KERNEL); - if (unlikely(!wdt)) { - rc = -ENOMEM; - goto out_release; - } + if (unlikely(!wdt)) + return -ENOMEM; wdt->dev = &pdev->dev; - wdt->base = devm_ioremap(&pdev->dev, res->start, resource_size(res)); + wdt->clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(wdt->clk)) { + /* + * Clock framework support is optional, continue on + * anyways if we don't find a matching clock. + */ + wdt->clk = NULL; + } + + wdt->base = devm_request_and_ioremap(wdt->dev, res); if (unlikely(!wdt->base)) { - rc = -ENXIO; - goto out_err; + rc = -EADDRNOTAVAIL; + goto err; } - rc = register_reboot_notifier(&sh_wdt_notifier); + watchdog_set_nowayout(&sh_wdt_dev, nowayout); + watchdog_set_drvdata(&sh_wdt_dev, wdt); + + spin_lock_init(&wdt->lock); + + rc = sh_wdt_set_heartbeat(&sh_wdt_dev, heartbeat); if (unlikely(rc)) { - dev_err(&pdev->dev, - "Can't register reboot notifier (err=%d)\n", rc); - goto out_unmap; + /* Default timeout if invalid */ + sh_wdt_set_heartbeat(&sh_wdt_dev, WATCHDOG_HEARTBEAT); + + dev_warn(&pdev->dev, + "heartbeat value must be 1<=x<=3600, using %d\n", + sh_wdt_dev.timeout); } - sh_wdt_miscdev.parent = wdt->dev; + dev_info(&pdev->dev, "configured with heartbeat=%d sec (nowayout=%d)\n", + sh_wdt_dev.timeout, nowayout); - rc = misc_register(&sh_wdt_miscdev); + rc = watchdog_register_device(&sh_wdt_dev); if (unlikely(rc)) { - dev_err(&pdev->dev, - "Can't register miscdev on minor=%d (err=%d)\n", - sh_wdt_miscdev.minor, rc); - goto out_unreg; + dev_err(&pdev->dev, "Can't register watchdog (err=%d)\n", rc); + goto err; } init_timer(&wdt->timer); @@ -388,20 +285,15 @@ static int __devinit sh_wdt_probe(struct platform_device *pdev) wdt->timer.expires = next_ping_period(clock_division_ratio); platform_set_drvdata(pdev, wdt); - sh_wdt_dev = pdev; dev_info(&pdev->dev, "initialized.\n"); + pm_runtime_enable(&pdev->dev); + return 0; -out_unreg: - unregister_reboot_notifier(&sh_wdt_notifier); -out_unmap: - devm_iounmap(&pdev->dev, wdt->base); -out_err: - devm_kfree(&pdev->dev, wdt); -out_release: - devm_release_mem_region(&pdev->dev, res->start, resource_size(res)); +err: + clk_put(wdt->clk); return rc; } @@ -409,36 +301,35 @@ out_release: static int __devexit sh_wdt_remove(struct platform_device *pdev) { struct sh_wdt *wdt = platform_get_drvdata(pdev); - struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); platform_set_drvdata(pdev, NULL); - misc_deregister(&sh_wdt_miscdev); + watchdog_unregister_device(&sh_wdt_dev); - sh_wdt_dev = NULL; - - unregister_reboot_notifier(&sh_wdt_notifier); - devm_release_mem_region(&pdev->dev, res->start, resource_size(res)); - devm_iounmap(&pdev->dev, wdt->base); - devm_kfree(&pdev->dev, wdt); + pm_runtime_disable(&pdev->dev); + clk_put(wdt->clk); return 0; } +static void sh_wdt_shutdown(struct platform_device *pdev) +{ + sh_wdt_stop(&sh_wdt_dev); +} + static struct platform_driver sh_wdt_driver = { .driver = { .name = DRV_NAME, .owner = THIS_MODULE, }, - .probe = sh_wdt_probe, - .remove = __devexit_p(sh_wdt_remove), + .probe = sh_wdt_probe, + .remove = __devexit_p(sh_wdt_remove), + .shutdown = sh_wdt_shutdown, }; static int __init sh_wdt_init(void) { - int rc; - if (unlikely(clock_division_ratio < 0x5 || clock_division_ratio > 0x7)) { clock_division_ratio = WTCSR_CKS_4096; @@ -447,17 +338,6 @@ static int __init sh_wdt_init(void) clock_division_ratio); } - rc = sh_wdt_set_heartbeat(heartbeat); - if (unlikely(rc)) { - heartbeat = WATCHDOG_HEARTBEAT; - - pr_info("heartbeat value must be 1<=x<=3600, using %d\n", - heartbeat); - } - - pr_info("configured with heartbeat=%d sec (nowayout=%d)\n", - heartbeat, nowayout); - return platform_driver_register(&sh_wdt_driver); } |
