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path: root/drivers/watchdog/rc32434_wdt.c
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Diffstat (limited to 'drivers/watchdog/rc32434_wdt.c')
-rw-r--r--drivers/watchdog/rc32434_wdt.c153
1 files changed, 95 insertions, 58 deletions
diff --git a/drivers/watchdog/rc32434_wdt.c b/drivers/watchdog/rc32434_wdt.c
index f3553fa..f6cccc9 100644
--- a/drivers/watchdog/rc32434_wdt.c
+++ b/drivers/watchdog/rc32434_wdt.c
@@ -17,27 +17,29 @@
*
*/
-#include <linux/module.h>
-#include <linux/types.h>
-#include <linux/kernel.h>
-#include <linux/fs.h>
-#include <linux/mm.h>
-#include <linux/miscdevice.h>
-#include <linux/watchdog.h>
-#include <linux/reboot.h>
-#include <linux/smp_lock.h>
-#include <linux/init.h>
-#include <linux/platform_device.h>
-#include <linux/uaccess.h>
-
-#include <asm/bootinfo.h>
-#include <asm/time.h>
-#include <asm/mach-rc32434/integ.h>
-
-#define VERSION "0.4"
+#include <linux/module.h> /* For module specific items */
+#include <linux/moduleparam.h> /* For new moduleparam's */
+#include <linux/types.h> /* For standard types (like size_t) */
+#include <linux/errno.h> /* For the -ENODEV/... values */
+#include <linux/kernel.h> /* For printk/panic/... */
+#include <linux/fs.h> /* For file operations */
+#include <linux/miscdevice.h> /* For MODULE_ALIAS_MISCDEV
+ (WATCHDOG_MINOR) */
+#include <linux/watchdog.h> /* For the watchdog specific items */
+#include <linux/init.h> /* For __init/__exit/... */
+#include <linux/platform_device.h> /* For platform_driver framework */
+#include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */
+#include <linux/uaccess.h> /* For copy_to_user/put_user/... */
+
+#include <asm/mach-rc32434/integ.h> /* For the Watchdog registers */
+
+#define PFX KBUILD_MODNAME ": "
+
+#define VERSION "1.0"
static struct {
unsigned long inuse;
+ spinlock_t io_lock;
} rc32434_wdt_device;
static struct integ __iomem *wdt_reg;
@@ -58,6 +60,9 @@ extern unsigned int idt_cpu_freq;
#define WATCHDOG_TIMEOUT 20
static int timeout = WATCHDOG_TIMEOUT;
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout, "Watchdog timeout value, in seconds (default="
+ WATCHDOG_TIMEOUT ")");
static int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, int, 0);
@@ -68,10 +73,29 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
#define SET_BITS(addr, or, nand) \
writel((readl(&addr) | or) & ~nand, &addr)
+static int rc32434_wdt_set(int new_timeout)
+{
+ int max_to = WTCOMP2SEC((u32)-1);
+
+ if (new_timeout < 0 || new_timeout > max_to) {
+ printk(KERN_ERR PFX "timeout value must be between 0 and %d",
+ max_to);
+ return -EINVAL;
+ }
+ timeout = new_timeout;
+ spin_lock(&rc32434_wdt_device.io_lock);
+ writel(SEC2WTCOMP(timeout), &wdt_reg->wtcompare);
+ spin_unlock(&rc32434_wdt_device.io_lock);
+
+ return 0;
+}
+
static void rc32434_wdt_start(void)
{
u32 or, nand;
+ spin_lock(&rc32434_wdt_device.io_lock);
+
/* zero the counter before enabling */
writel(0, &wdt_reg->wtcount);
@@ -85,38 +109,35 @@ static void rc32434_wdt_start(void)
SET_BITS(wdt_reg->errcs, or, nand);
+ /* set the timeout (either default or based on module param) */
+ rc32434_wdt_set(timeout);
+
/* reset WTC timeout bit and enable WDT */
nand = 1 << RC32434_WTC_TO;
or = 1 << RC32434_WTC_EN;
SET_BITS(wdt_reg->wtc, or, nand);
+
+ spin_unlock(&rc32434_wdt_device.io_lock);
+ printk(KERN_INFO PFX "Started watchdog timer.\n");
}
static void rc32434_wdt_stop(void)
{
+ spin_lock(&rc32434_wdt_device.io_lock);
+
/* Disable WDT */
SET_BITS(wdt_reg->wtc, 0, 1 << RC32434_WTC_EN);
-}
-
-static int rc32434_wdt_set(int new_timeout)
-{
- int max_to = WTCOMP2SEC((u32)-1);
-
- if (new_timeout < 0 || new_timeout > max_to) {
- printk(KERN_ERR KBUILD_MODNAME
- ": timeout value must be between 0 and %d",
- max_to);
- return -EINVAL;
- }
- timeout = new_timeout;
- writel(SEC2WTCOMP(timeout), &wdt_reg->wtcompare);
- return 0;
+ spin_unlock(&rc32434_wdt_device.io_lock);
+ printk(KERN_INFO PFX "Stopped watchdog timer.\n");
}
static void rc32434_wdt_ping(void)
{
+ spin_lock(&rc32434_wdt_device.io_lock);
writel(0, &wdt_reg->wtcount);
+ spin_unlock(&rc32434_wdt_device.io_lock);
}
static int rc32434_wdt_open(struct inode *inode, struct file *file)
@@ -137,11 +158,10 @@ static int rc32434_wdt_release(struct inode *inode, struct file *file)
{
if (expect_close == 42) {
rc32434_wdt_stop();
- printk(KERN_INFO KBUILD_MODNAME ": disabling watchdog timer\n");
module_put(THIS_MODULE);
} else {
- printk(KERN_CRIT KBUILD_MODNAME
- ": device closed unexpectedly. WDT will not stop !\n");
+ printk(KERN_CRIT PFX
+ "device closed unexpectedly. WDT will not stop!\n");
rc32434_wdt_ping();
}
clear_bit(0, &rc32434_wdt_device.inuse);
@@ -185,8 +205,9 @@ static long rc32434_wdt_ioctl(struct file *file, unsigned int cmd,
.identity = "RC32434_WDT Watchdog",
};
switch (cmd) {
- case WDIOC_KEEPALIVE:
- rc32434_wdt_ping();
+ case WDIOC_GETSUPPORT:
+ if (copy_to_user(argp, &ident, sizeof(ident)))
+ return -EFAULT;
break;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
@@ -194,10 +215,6 @@ static long rc32434_wdt_ioctl(struct file *file, unsigned int cmd,
if (copy_to_user(argp, &value, sizeof(int)))
return -EFAULT;
break;
- case WDIOC_GETSUPPORT:
- if (copy_to_user(argp, &ident, sizeof(ident)))
- return -EFAULT;
- break;
case WDIOC_SETOPTIONS:
if (copy_from_user(&value, argp, sizeof(int)))
return -EFAULT;
@@ -212,6 +229,9 @@ static long rc32434_wdt_ioctl(struct file *file, unsigned int cmd,
return -EINVAL;
}
break;
+ case WDIOC_KEEPALIVE:
+ rc32434_wdt_ping();
+ break;
case WDIOC_SETTIMEOUT:
if (copy_from_user(&new_timeout, argp, sizeof(int)))
return -EFAULT;
@@ -227,7 +247,7 @@ static long rc32434_wdt_ioctl(struct file *file, unsigned int cmd,
return 0;
}
-static struct file_operations rc32434_wdt_fops = {
+static const struct file_operations rc32434_wdt_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = rc32434_wdt_write,
@@ -242,8 +262,8 @@ static struct miscdevice rc32434_wdt_miscdev = {
.fops = &rc32434_wdt_fops,
};
-static char banner[] __devinitdata = KERN_INFO KBUILD_MODNAME
- ": Watchdog Timer version " VERSION ", timer margin: %d sec\n";
+static char banner[] __devinitdata = KERN_INFO PFX
+ "Watchdog Timer version " VERSION ", timer margin: %d sec\n";
static int __devinit rc32434_wdt_probe(struct platform_device *pdev)
{
@@ -252,22 +272,33 @@ static int __devinit rc32434_wdt_probe(struct platform_device *pdev)
r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rb532_wdt_res");
if (!r) {
- printk(KERN_ERR KBUILD_MODNAME
- "failed to retrieve resources\n");
+ printk(KERN_ERR PFX "failed to retrieve resources\n");
return -ENODEV;
}
wdt_reg = ioremap_nocache(r->start, r->end - r->start);
if (!wdt_reg) {
- printk(KERN_ERR KBUILD_MODNAME
- "failed to remap I/O resources\n");
+ printk(KERN_ERR PFX "failed to remap I/O resources\n");
return -ENXIO;
}
+ spin_lock_init(&rc32434_wdt_device.io_lock);
+
+ /* Make sure the watchdog is not running */
+ rc32434_wdt_stop();
+
+ /* Check that the heartbeat value is within it's range;
+ * if not reset to the default */
+ if (rc32434_wdt_set(timeout)) {
+ rc32434_wdt_set(WATCHDOG_TIMEOUT);
+ printk(KERN_INFO PFX
+ "timeout value must be between 0 and %d\n",
+ WTCOMP2SEC((u32)-1));
+ }
+
ret = misc_register(&rc32434_wdt_miscdev);
if (ret < 0) {
- printk(KERN_ERR KBUILD_MODNAME
- "failed to register watchdog device\n");
+ printk(KERN_ERR PFX "failed to register watchdog device\n");
goto unmap;
}
@@ -287,22 +318,28 @@ static int __devexit rc32434_wdt_remove(struct platform_device *pdev)
return 0;
}
-static struct platform_driver rc32434_wdt = {
- .probe = rc32434_wdt_probe,
- .remove = __devexit_p(rc32434_wdt_remove),
- .driver = {
- .name = "rc32434_wdt",
+static void rc32434_wdt_shutdown(struct platform_device *pdev)
+{
+ rc32434_wdt_stop();
+}
+
+static struct platform_driver rc32434_wdt_driver = {
+ .probe = rc32434_wdt_probe,
+ .remove = __devexit_p(rc32434_wdt_remove),
+ .shutdown = rc32434_wdt_shutdown,
+ .driver = {
+ .name = "rc32434_wdt",
}
};
static int __init rc32434_wdt_init(void)
{
- return platform_driver_register(&rc32434_wdt);
+ return platform_driver_register(&rc32434_wdt_driver);
}
static void __exit rc32434_wdt_exit(void)
{
- platform_driver_unregister(&rc32434_wdt);
+ platform_driver_unregister(&rc32434_wdt_driver);
}
module_init(rc32434_wdt_init);
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