watchdog: Convert txx9wdt driver to watchdog framework
Axel Lin [Fri, 16 Mar 2012 03:53:53 +0000 (11:53 +0800)]
This patch converts txx9wdt driver to watchdog framework.
Also use devm_* APIs to save a few error handling code.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

drivers/watchdog/Kconfig
drivers/watchdog/txx9wdt.c

index e25a464..5d8cd69 100644 (file)
@@ -1003,6 +1003,7 @@ config AR7_WDT
 config TXX9_WDT
        tristate "Toshiba TXx9 Watchdog Timer"
        depends on CPU_TX39XX || CPU_TX49XX
+       select WATCHDOG_CORE
        help
          Hardware driver for the built-in watchdog timer on TXx9 MIPS SoCs.
 
index d02804c..53f1b17 100644 (file)
@@ -15,9 +15,7 @@
 #include <linux/types.h>
 #include <linux/miscdevice.h>
 #include <linux/watchdog.h>
-#include <linux/fs.h>
 #include <linux/init.h>
-#include <linux/uaccess.h>
 #include <linux/platform_device.h>
 #include <linux/clk.h>
 #include <linux/err.h>
@@ -43,20 +41,19 @@ MODULE_PARM_DESC(nowayout,
 #define WD_TIMER_CLK   (clk_get_rate(txx9_imclk) / (2 << WD_TIMER_CCD))
 #define WD_MAX_TIMEOUT ((0xffffffff >> (32 - TXX9_TIMER_BITS)) / WD_TIMER_CLK)
 
-static unsigned long txx9wdt_alive;
-static int expect_close;
 static struct txx9_tmr_reg __iomem *txx9wdt_reg;
 static struct clk *txx9_imclk;
 static DEFINE_SPINLOCK(txx9_lock);
 
-static void txx9wdt_ping(void)
+static int txx9wdt_ping(struct watchdog_device *wdt_dev)
 {
        spin_lock(&txx9_lock);
        __raw_writel(TXx9_TMWTMR_TWIE | TXx9_TMWTMR_TWC, &txx9wdt_reg->wtmr);
        spin_unlock(&txx9_lock);
+       return 0;
 }
 
-static void txx9wdt_start(void)
+static int txx9wdt_start(struct watchdog_device *wdt_dev)
 {
        spin_lock(&txx9_lock);
        __raw_writel(WD_TIMER_CLK * timeout, &txx9wdt_reg->cpra);
@@ -66,120 +63,44 @@ static void txx9wdt_start(void)
                     &txx9wdt_reg->tcr);
        __raw_writel(TXx9_TMWTMR_TWIE | TXx9_TMWTMR_TWC, &txx9wdt_reg->wtmr);
        spin_unlock(&txx9_lock);
+       return 0;
 }
 
-static void txx9wdt_stop(void)
+static int txx9wdt_stop(struct watchdog_device *wdt_dev)
 {
        spin_lock(&txx9_lock);
        __raw_writel(TXx9_TMWTMR_WDIS, &txx9wdt_reg->wtmr);
        __raw_writel(__raw_readl(&txx9wdt_reg->tcr) & ~TXx9_TMTCR_TCE,
                     &txx9wdt_reg->tcr);
        spin_unlock(&txx9_lock);
-}
-
-static int txx9wdt_open(struct inode *inode, struct file *file)
-{
-       if (test_and_set_bit(0, &txx9wdt_alive))
-               return -EBUSY;
-
-       if (__raw_readl(&txx9wdt_reg->tcr) & TXx9_TMTCR_TCE) {
-               clear_bit(0, &txx9wdt_alive);
-               return -EBUSY;
-       }
-
-       if (nowayout)
-               __module_get(THIS_MODULE);
-
-       txx9wdt_start();
-       return nonseekable_open(inode, file);
-}
-
-static int txx9wdt_release(struct inode *inode, struct file *file)
-{
-       if (expect_close)
-               txx9wdt_stop();
-       else {
-               pr_crit("Unexpected close, not stopping watchdog!\n");
-               txx9wdt_ping();
-       }
-       clear_bit(0, &txx9wdt_alive);
-       expect_close = 0;
        return 0;
 }
 
-static ssize_t txx9wdt_write(struct file *file, const char __user *data,
-                            size_t len, loff_t *ppos)
+static int txx9wdt_set_timeout(struct watchdog_device *wdt_dev,
+                              unsigned int new_timeout)
 {
-       if (len) {
-               if (!nowayout) {
-                       size_t i;
-
-                       expect_close = 0;
-                       for (i = 0; i != len; i++) {
-                               char c;
-                               if (get_user(c, data + i))
-                                       return -EFAULT;
-                               if (c == 'V')
-                                       expect_close = 1;
-                       }
-               }
-               txx9wdt_ping();
-       }
-       return len;
+       timeout = new_timeout;
+       txx9wdt_stop(wdt_dev);
+       txx9wdt_start(wdt_dev);
+       return 0;
 }
 
-static long txx9wdt_ioctl(struct file *file, unsigned int cmd,
-                                                       unsigned long arg)
-{
-       void __user *argp = (void __user *)arg;
-       int __user *p = argp;
-       int new_timeout;
-       static const struct watchdog_info ident = {
-               .options =              WDIOF_SETTIMEOUT |
-                                       WDIOF_KEEPALIVEPING |
-                                       WDIOF_MAGICCLOSE,
-               .firmware_version =     0,
-               .identity =             "Hardware Watchdog for TXx9",
-       };
-
-       switch (cmd) {
-       case WDIOC_GETSUPPORT:
-               return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
-       case WDIOC_GETSTATUS:
-       case WDIOC_GETBOOTSTATUS:
-               return put_user(0, p);
-       case WDIOC_KEEPALIVE:
-               txx9wdt_ping();
-               return 0;
-       case WDIOC_SETTIMEOUT:
-               if (get_user(new_timeout, p))
-                       return -EFAULT;
-               if (new_timeout < 1 || new_timeout > WD_MAX_TIMEOUT)
-                       return -EINVAL;
-               timeout = new_timeout;
-               txx9wdt_stop();
-               txx9wdt_start();
-               /* Fall */
-       case WDIOC_GETTIMEOUT:
-               return put_user(timeout, p);
-       default:
-               return -ENOTTY;
-       }
-}
+static const struct watchdog_info txx9wdt_info = {
+       .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+       .identity = "Hardware Watchdog for TXx9",
+};
 
-static const struct file_operations txx9wdt_fops = {
-       .owner          =       THIS_MODULE,
-       .llseek         =       no_llseek,
-       .write          =       txx9wdt_write,
-       .unlocked_ioctl =       txx9wdt_ioctl,
-       .open           =       txx9wdt_open,
-       .release        =       txx9wdt_release,
+static const struct watchdog_ops txx9wdt_ops = {
+       .owner = THIS_MODULE,
+       .start = txx9wdt_start,
+       .stop = txx9wdt_stop,
+       .ping = txx9wdt_ping,
+       .set_timeout = txx9wdt_set_timeout,
 };
 
-static struct miscdevice txx9wdt_miscdev = {
-       .minor  =       WATCHDOG_MINOR,
-       .name   =       "watchdog",
-       .fops   =       &txx9wdt_fops,
+static struct watchdog_device txx9wdt = {
+       .info = &txx9wdt_info,
+       .ops = &txx9wdt_ops,
 };
 
 static int __init txx9wdt_probe(struct platform_device *dev)
@@ -201,26 +122,24 @@ static int __init txx9wdt_probe(struct platform_device *dev)
        }
 
        res = platform_get_resource(dev, IORESOURCE_MEM, 0);
-       if (!res)
-               goto exit_busy;
-       if (!devm_request_mem_region(&dev->dev, res->start, resource_size(res),
-                                    "txx9wdt"))
-               goto exit_busy;
-       txx9wdt_reg = devm_ioremap(&dev->dev, res->start, resource_size(res));
-       if (!txx9wdt_reg)
-               goto exit_busy;
-
-       ret = misc_register(&txx9wdt_miscdev);
-       if (ret) {
+       txx9wdt_reg = devm_request_and_ioremap(&dev->dev, res);
+       if (!txx9wdt_reg) {
+               ret = -EBUSY;
                goto exit;
        }
 
+       txx9wdt.min_timeout = 1;
+       txx9wdt.max_timeout = WD_MAX_TIMEOUT;
+       watchdog_set_nowayout(&txx9wdt, nowayout);
+
+       ret = watchdog_register_device(&txx9wdt);
+       if (ret)
+               goto exit;
+
        pr_info("Hardware Watchdog Timer: timeout=%d sec (max %ld) (nowayout= %d)\n",
                timeout, WD_MAX_TIMEOUT, nowayout);
 
        return 0;
-exit_busy:
-       ret = -EBUSY;
 exit:
        if (txx9_imclk) {
                clk_disable(txx9_imclk);
@@ -231,7 +150,7 @@ exit:
 
 static int __exit txx9wdt_remove(struct platform_device *dev)
 {
-       misc_deregister(&txx9wdt_miscdev);
+       watchdog_unregister_device(&txx9wdt);
        clk_disable(txx9_imclk);
        clk_put(txx9_imclk);
        return 0;
@@ -239,7 +158,7 @@ static int __exit txx9wdt_remove(struct platform_device *dev)
 
 static void txx9wdt_shutdown(struct platform_device *dev)
 {
-       txx9wdt_stop();
+       txx9wdt_stop(&txx9wdt);
 }
 
 static struct platform_driver txx9wdt_driver = {