*
* 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
#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"
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;
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));
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);
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;
}
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;
} 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,
.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)
+static int sh_wdt_probe(struct platform_device *pdev)
{
struct sh_wdt *wdt;
struct resource *res;
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);
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;
}
-static int __devexit sh_wdt_remove(struct platform_device *pdev)
+static int 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 = 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;
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);
}
projects / karo-tx-linux.git / blobdiff