[WATCHDOG 27/57] mpcore watchdog: unlocked_ioctl and BKl work
authorAlan Cox <alan@redhat.com>
Mon, 19 May 2008 13:07:15 +0000 (14:07 +0100)
committerWim Van Sebroeck <wim@iguana.be>
Fri, 13 Jun 2008 19:51:55 +0000 (19:51 +0000)
Review and switch to unlocked_ioctl

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
drivers/watchdog/mpcore_wdt.c

index 009573b81496fa060bc8bb33722bf46337be1641..5e58f8b73d00d0c56769121ddd4e35b921df3da1 100644 (file)
@@ -29,9 +29,9 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
+#include <linux/uaccess.h>
 
 #include <asm/hardware/arm_twd.h>
-#include <asm/uaccess.h>
 
 struct mpcore_wdt {
        unsigned long   timer_alive;
@@ -43,17 +43,20 @@ struct mpcore_wdt {
 };
 
 static struct platform_device *mpcore_wdt_dev;
-
 extern unsigned int mpcore_timer_rate;
 
 #define TIMER_MARGIN   60
 static int mpcore_margin = TIMER_MARGIN;
 module_param(mpcore_margin, int, 0);
-MODULE_PARM_DESC(mpcore_margin, "MPcore timer margin in seconds. (0<mpcore_margin<65536, default=" __MODULE_STRING(TIMER_MARGIN) ")");
+MODULE_PARM_DESC(mpcore_margin,
+       "MPcore timer margin in seconds. (0 < mpcore_margin < 65536, default="
+                               __MODULE_STRING(TIMER_MARGIN) ")");
 
 static int nowayout = WATCHDOG_NOWAYOUT;
 module_param(nowayout, int, 0);
-MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+MODULE_PARM_DESC(nowayout,
+       "Watchdog cannot be stopped once started (default="
+                               __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 
 #define ONLY_TESTING   0
 static int mpcore_noboot = ONLY_TESTING;
@@ -70,14 +73,12 @@ static irqreturn_t mpcore_wdt_fire(int irq, void *arg)
 
        /* Check it really was our interrupt */
        if (readl(wdt->base + TWD_WDOG_INTSTAT)) {
-               dev_printk(KERN_CRIT, wdt->dev, "Triggered - Reboot ignored.\n");
-
+               dev_printk(KERN_CRIT, wdt->dev,
+                                       "Triggered - Reboot ignored.\n");
                /* Clear the interrupt on the watchdog */
                writel(1, wdt->base + TWD_WDOG_INTSTAT);
-
                return IRQ_HANDLED;
        }
-
        return IRQ_NONE;
 }
 
@@ -96,22 +97,26 @@ static void mpcore_wdt_keepalive(struct mpcore_wdt *wdt)
        count = (mpcore_timer_rate / 256) * mpcore_margin;
 
        /* Reload the counter */
+       spin_lock(&wdt_lock);
        writel(count + wdt->perturb, wdt->base + TWD_WDOG_LOAD);
-
        wdt->perturb = wdt->perturb ? 0 : 1;
+       spin_unlock(&wdt_lock);
 }
 
 static void mpcore_wdt_stop(struct mpcore_wdt *wdt)
 {
+       spin_lock(&wdt_lock);
        writel(0x12345678, wdt->base + TWD_WDOG_DISABLE);
        writel(0x87654321, wdt->base + TWD_WDOG_DISABLE);
        writel(0x0, wdt->base + TWD_WDOG_CONTROL);
+       spin_unlock(&wdt_lock);
 }
 
 static void mpcore_wdt_start(struct mpcore_wdt *wdt)
 {
        dev_printk(KERN_INFO, wdt->dev, "enabling watchdog.\n");
 
+       spin_lock(&wdt_lock);
        /* This loads the count register but does NOT start the count yet */
        mpcore_wdt_keepalive(wdt);
 
@@ -122,6 +127,7 @@ static void mpcore_wdt_start(struct mpcore_wdt *wdt)
                /* Enable watchdog - prescale=256, watchdog mode=1, enable=1 */
                writel(0x0000FF09, wdt->base + TWD_WDOG_CONTROL);
        }
+       spin_unlock(&wdt_lock);
 }
 
 static int mpcore_wdt_set_heartbeat(int t)
@@ -164,10 +170,11 @@ static int mpcore_wdt_release(struct inode *inode, struct file *file)
         *      Shut off the timer.
         *      Lock it in if it's a module and we set nowayout
         */
-       if (wdt->expect_close == 42) {
+       if (wdt->expect_close == 42)
                mpcore_wdt_stop(wdt);
-       } else {
-               dev_printk(KERN_CRIT, wdt->dev, "unexpected close, not stopping watchdog!\n");
+       else {
+               dev_printk(KERN_CRIT, wdt->dev,
+                               "unexpected close, not stopping watchdog!\n");
                mpcore_wdt_keepalive(wdt);
        }
        clear_bit(0, &wdt->timer_alive);
@@ -175,7 +182,8 @@ static int mpcore_wdt_release(struct inode *inode, struct file *file)
        return 0;
 }
 
-static ssize_t mpcore_wdt_write(struct file *file, const char *data, size_t len, loff_t *ppos)
+static ssize_t mpcore_wdt_write(struct file *file, const char *data,
+                                               size_t len, loff_t *ppos)
 {
        struct mpcore_wdt *wdt = file->private_data;
 
@@ -210,8 +218,8 @@ static struct watchdog_info ident = {
        .identity               = "MPcore Watchdog",
 };
 
-static int mpcore_wdt_ioctl(struct inode *inode, struct file *file,
-                            unsigned int cmd, unsigned long arg)
+static long mpcore_wdt_ioctl(struct file *file, unsigned int cmd,
+                                                       unsigned long arg)
 {
        struct mpcore_wdt *wdt = file->private_data;
        int ret;
@@ -301,7 +309,7 @@ static const struct file_operations mpcore_wdt_fops = {
        .owner          = THIS_MODULE,
        .llseek         = no_llseek,
        .write          = mpcore_wdt_write,
-       .ioctl          = mpcore_wdt_ioctl,
+       .unlocked_ioctl = mpcore_wdt_ioctl,
        .open           = mpcore_wdt_open,
        .release        = mpcore_wdt_release,
 };
@@ -349,14 +357,17 @@ static int __devinit mpcore_wdt_probe(struct platform_device *dev)
        mpcore_wdt_miscdev.parent = &dev->dev;
        ret = misc_register(&mpcore_wdt_miscdev);
        if (ret) {
-               dev_printk(KERN_ERR, _dev, "cannot register miscdev on minor=%d (err=%d)\n",
-                          WATCHDOG_MINOR, ret);
+               dev_printk(KERN_ERR, _dev,
+                       "cannot register miscdev on minor=%d (err=%d)\n",
+                                                       WATCHDOG_MINOR, ret);
                goto err_misc;
        }
 
-       ret = request_irq(wdt->irq, mpcore_wdt_fire, IRQF_DISABLED, "mpcore_wdt", wdt);
+       ret = request_irq(wdt->irq, mpcore_wdt_fire, IRQF_DISABLED,
+                                                       "mpcore_wdt", wdt);
        if (ret) {
-               dev_printk(KERN_ERR, _dev, "cannot register IRQ%d for watchdog\n", wdt->irq);
+               dev_printk(KERN_ERR, _dev,
+                       "cannot register IRQ%d for watchdog\n", wdt->irq);
                goto err_irq;
        }
 
@@ -415,7 +426,7 @@ static int __init mpcore_wdt_init(void)
         */
        if (mpcore_wdt_set_heartbeat(mpcore_margin)) {
                mpcore_wdt_set_heartbeat(TIMER_MARGIN);
-               printk(KERN_INFO "mpcore_margin value must be 0<mpcore_margin<65536, using %d\n",
+               printk(KERN_INFO "mpcore_margin value must be 0 < mpcore_margin < 65536, using %d\n",
                        TIMER_MARGIN);
        }