[WATCHDOG] Mixcom Watchdog - checkcard

[safe/jmp/linux-2.6] / drivers / char / watchdog / pnx4008_wdt.c

diff --git a/drivers/char/watchdog/pnx4008_wdt.c b/drivers/char/watchdog/pnx4008_wdt.c
index 465dfd3..22f8873 100644 (file)
--- a/drivers/char/watchdog/pnx4008_wdt.c
+++ b/drivers/char/watchdog/pnx4008_wdt.c
@@ -14,7 +14,6 @@
  * or implied.
  */
 
-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/types.h>
@@ -28,6 +27,7 @@
 #include <linux/device.h>
 #include <linux/platform_device.h>
 #include <linux/clk.h>
+#include <linux/spinlock.h>
 
 #include <asm/hardware.h>
 #include <asm/uaccess.h>
@@ -80,6 +80,7 @@
 static int nowayout = WATCHDOG_NOWAYOUT;
 static int heartbeat = DEFAULT_HEARTBEAT;
 
+static spinlock_t io_lock;
 static unsigned long wdt_status;
 #define WDT_IN_USE        0
 #define WDT_OK_TO_CLOSE   1
@@ -94,13 +95,16 @@ struct clk          *wdt_clk;
 
 static void wdt_enable(void)
 {
+       spin_lock(&io_lock);
+
        if (wdt_clk)
                clk_set_rate(wdt_clk, 1);
 
        /* stop counter, initiate counter reset */
        __raw_writel(RESET_COUNT, WDTIM_CTRL(wdt_base));
        /*wait for reset to complete. 100% guarantee event */
-       while (__raw_readl(WDTIM_COUNTER(wdt_base)));
+       while (__raw_readl(WDTIM_COUNTER(wdt_base)))
+               cpu_relax();
        /* internal and external reset, stop after that */
        __raw_writel(M_RES2 | STOP_COUNT0 | RESET_COUNT0,
                WDTIM_MCTRL(wdt_base));
@@ -113,13 +117,19 @@ static void wdt_enable(void)
        __raw_writel(heartbeat * WDOG_COUNTER_RATE, WDTIM_MATCH0(wdt_base));
        /*enable counter, stop when debugger active */
        __raw_writel(COUNT_ENAB | DEBUG_EN, WDTIM_CTRL(wdt_base));
+
+       spin_unlock(&io_lock);
 }
 
 static void wdt_disable(void)
 {
+       spin_lock(&io_lock);
+
        __raw_writel(0, WDTIM_CTRL(wdt_base));  /*stop counter */
        if (wdt_clk)
                clk_set_rate(wdt_clk, 0);
+
+       spin_unlock(&io_lock);
 }
 
 static int pnx4008_wdt_open(struct inode *inode, struct file *file)
@@ -138,10 +148,6 @@ static ssize_t
 pnx4008_wdt_write(struct file *file, const char *data, size_t len,
                  loff_t * ppos)
 {
-       /*  Can't seek (pwrite) on this device  */
-       if (ppos != &file->f_pos)
-               return -ESPIPE;
-
        if (len) {
                if (!nowayout) {
                        size_t i;
@@ -173,7 +179,7 @@ static int
 pnx4008_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
                  unsigned long arg)
 {
-       int ret = -ENOIOCTLCMD;
+       int ret = -ENOTTY;
        int time;
 
        switch (cmd) {
@@ -228,7 +234,7 @@ static int pnx4008_wdt_release(struct inode *inode, struct file *file)
        return 0;
 }
 
-static struct file_operations pnx4008_wdt_fops = {
+static const struct file_operations pnx4008_wdt_fops = {
        .owner = THIS_MODULE,
        .llseek = no_llseek,
        .write = pnx4008_wdt_write,
@@ -248,6 +254,8 @@ static int pnx4008_wdt_probe(struct platform_device *pdev)
        int ret = 0, size;
        struct resource *res;
 
+       spin_lock_init(&io_lock);
+
        if (heartbeat < 1 || heartbeat > MAX_HEARTBEAT)
                heartbeat = DEFAULT_HEARTBEAT;
 
@@ -271,7 +279,8 @@ static int pnx4008_wdt_probe(struct platform_device *pdev)
        wdt_base = (void __iomem *)IO_ADDRESS(res->start);
 
        wdt_clk = clk_get(&pdev->dev, "wdt_ck");
-       if (!wdt_clk) {
+       if (IS_ERR(wdt_clk)) {
+               ret = PTR_ERR(wdt_clk);
                release_resource(wdt_mem);
                kfree(wdt_mem);
                goto out;