cbus-retu-wdt: Some fixes

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@25832 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 127 insertions, 0 deletions

diff --git a/target/linux/omap24xx/patches-2.6.38/530-cbus-retu-wdt-preemptible.patch b/target/linux/omap24xx/patches-2.6.38/530-cbus-retu-wdt-preemptible.patch
new file mode 100644
index 000000000..fecbd09a7
--- /dev/null
+++ b/target/linux/omap24xx/patches-2.6.38/530-cbus-retu-wdt-preemptible.patch
@@ -0,0 +1,127 @@
+Index: linux-2.6.38-rc6/drivers/cbus/retu-wdt.c
+===================================================================
+--- linux-2.6.38-rc6.orig/drivers/cbus/retu-wdt.c	2011-03-02 16:08:59.022211654 +0100
++++ linux-2.6.38-rc6/drivers/cbus/retu-wdt.c	2011-03-02 16:29:43.215284501 +0100
+@@ -58,13 +58,11 @@ struct retu_wdt_dev {
+ 	struct device		*dev;
+ 	int			users;
+ 	struct miscdevice	retu_wdt_miscdev;
+-	struct timer_list	ping_timer;
++	struct delayed_work	ping_work;
+ };
+ 
+ static struct retu_wdt_dev *retu_wdt;
+ 
+-static void retu_wdt_set_ping_timer(unsigned long enable);
+-
+ static int _retu_modify_counter(unsigned int new)
+ {
+ 	if (retu_wdt)
+@@ -86,6 +84,31 @@ static int retu_modify_counter(unsigned
+ 	return 0;
+ }
+ 
++/*
++ * Since retu watchdog cannot be disabled in hardware, we must kick it
++ * with a timer until userspace watchdog software takes over. Do this
++ * unless /dev/watchdog is open or CONFIG_WATCHDOG_NOWAYOUT is set.
++ */
++static void retu_wdt_ping_enable(struct retu_wdt_dev *wdev)
++{
++	_retu_modify_counter(RETU_WDT_MAX_TIMER);
++	schedule_delayed_work(&wdev->ping_work,
++			      round_jiffies_relative(RETU_WDT_DEFAULT_TIMER * HZ));
++}
++
++static void retu_wdt_ping_disable(struct retu_wdt_dev *wdev)
++{
++	_retu_modify_counter(RETU_WDT_MAX_TIMER);
++	cancel_delayed_work_sync(&wdev->ping_work);
++}
++
++static void retu_wdt_ping_work(struct work_struct *work)
++{
++	struct retu_wdt_dev *wdev = container_of(to_delayed_work(work),
++					struct retu_wdt_dev, ping_work);
++	retu_wdt_ping_enable(wdev);
++}
++
+ static ssize_t retu_wdt_period_show(struct device *dev,
+ 				struct device_attribute *attr, char *buf)
+ {
+@@ -105,7 +128,7 @@ static ssize_t retu_wdt_period_store(str
+ 	int ret;
+ 
+ #ifdef CONFIG_WATCHDOG_NOWAYOUT
+-	retu_wdt_set_ping_timer(0);
++	retu_wdt_ping_disable(retu_wdt);
+ #endif
+ 
+ 	if (sscanf(buf, "%u", &new_period) != 1) {
+@@ -136,30 +159,13 @@ static DEVICE_ATTR(period, S_IRUGO | S_I
+ 			retu_wdt_period_store);
+ static DEVICE_ATTR(counter, S_IRUGO, retu_wdt_counter_show, NULL);
+ 
+-/*----------------------------------------------------------------------------*/
+-
+-/*
+- * Since retu watchdog cannot be disabled in hardware, we must kick it
+- * with a timer until userspace watchdog software takes over. Do this
+- * unless /dev/watchdog is open or CONFIG_WATCHDOG_NOWAYOUT is set.
+- */
+-static void retu_wdt_set_ping_timer(unsigned long enable)
+-{
+-	_retu_modify_counter(RETU_WDT_MAX_TIMER);
+-	if (enable)
+-		mod_timer(&retu_wdt->ping_timer,
+-				jiffies + RETU_WDT_DEFAULT_TIMER * HZ);
+-	else
+-		del_timer_sync(&retu_wdt->ping_timer);
+-}
+-
+ static int retu_wdt_open(struct inode *inode, struct file *file)
+ {
+ 	if (test_and_set_bit(1, (unsigned long *)&(retu_wdt->users)))
+ 		return -EBUSY;
+ 
+ 	file->private_data = (void *)retu_wdt;
+-	retu_wdt_set_ping_timer(0);
++	retu_wdt_ping_disable(retu_wdt);
+ 
+ 	return nonseekable_open(inode, file);
+ }
+@@ -169,7 +175,7 @@ static int retu_wdt_release(struct inode
+ 	struct retu_wdt_dev *wdev = file->private_data;
+ 
+ #ifndef CONFIG_WATCHDOG_NOWAYOUT
+-	retu_wdt_set_ping_timer(1);
++	retu_wdt_ping_enable(retu_wdt);
+ #endif
+ 	wdev->users = 0;
+ 
+@@ -232,7 +238,7 @@ static int __devinit retu_wdt_ping(void)
+ #ifdef CONFIG_WATCHDOG_NOWAYOUT
+ 	retu_modify_counter(RETU_WDT_MAX_TIMER);
+ #else
+-	retu_wdt_set_ping_timer(1);
++	retu_wdt_ping_enable(retu_wdt);
+ #endif
+ 
+ 	return 0;
+@@ -283,7 +289,7 @@ static int __init retu_wdt_probe(struct
+ 	if (ret)
+ 		goto free3;
+ 
+-	setup_timer(&wdev->ping_timer, retu_wdt_set_ping_timer, 1);
++	INIT_DELAYED_WORK(&wdev->ping_work, retu_wdt_ping_work);
+ 
+ 	/* passed as module parameter? */
+ 	ret = retu_modify_counter(counter_param);
+@@ -326,6 +332,7 @@ static int __devexit retu_wdt_remove(str
+ 	misc_deregister(&wdev->retu_wdt_miscdev);
+ 	device_remove_file(&pdev->dev, &dev_attr_period);
+ 	device_remove_file(&pdev->dev, &dev_attr_counter);
++	cancel_delayed_work_sync(&wdev->ping_work);
+ 	kfree(wdev);
+ 
+ 	return 0;