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From: Atal Shargorodsky <ext-atal.shargorodsky@nokia.com>
To: linux-kernel@vger.kernel.org
Cc: linux@arm.linux.org.uk,
	Atal Shargorodsky <ext-atal.shargorodsky@nokia.com>
Subject: [PATCH 5/6] Correct manage of activation states.
Date: Tue, 10 Mar 2009 18:03:55 +0200	[thread overview]
Message-ID: <6bfd4bd0c37668c409e3c2154ba2ab22c8a42800.1236609434.git.ext-atal.shargorodsky@nokia.com> (raw)
In-Reply-To: <0db69821a1be58e0b8889609ff2b2ee272aa3286.1236609434.git.ext-atal.shargorodsky@nokia.com>
In-Reply-To: <cbbca1e42421e2ada459f0c0881f087977e34eed.1236609434.git.ext-atal.shargorodsky@nokia.com>

Needed to support CONFIG_WATCHDOG_NOWAYOUT option.

Signed-off-by: Atal Shargorodsky <ext-atal.shargorodsky@nokia.com>
---
 drivers/watchdog/omap_wdt.c |   40 ++++++++++++++++++++++++++--------------
 1 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/drivers/watchdog/omap_wdt.c b/drivers/watchdog/omap_wdt.c
index d033139..6f6a524 100644
--- a/drivers/watchdog/omap_wdt.c
+++ b/drivers/watchdog/omap_wdt.c
@@ -56,10 +56,13 @@ MODULE_PARM_DESC(timer_margin, "initial watchdog timeout (in seconds)");
 static unsigned int wdt_trgr_pattern = 0x1234;
 static spinlock_t wdt_lock;
 
+#define OMAP_WDT_STATE_OPENED_BIT	1
+#define OMAP_WDT_STATE_ACTIVATED_BIT	8
+
 struct omap_wdt_dev {
 	void __iomem    *base;          /* physical */
 	struct device   *dev;
-	int             omap_wdt_users;
+	int             omap_wdt_state;
 	struct clk      *mpu_wdt_ick;
 	struct clk      *mpu_wdt_fck;
 	struct resource *mem;
@@ -152,19 +155,25 @@ static int omap_wdt_open(struct inode *inode, struct file *file)
 	struct omap_wdt_dev *wdev = platform_get_drvdata(omap_wdt_dev);
 	void __iomem *base = wdev->base;
 
-	if (test_and_set_bit(1, (unsigned long *)&(wdev->omap_wdt_users)))
+	if (test_and_set_bit(OMAP_WDT_STATE_OPENED_BIT,
+			(unsigned long *)&(wdev->omap_wdt_state)))
 		return -EBUSY;
 
 	omap_wdt_ick_enable(wdev->mpu_wdt_ick, 1);
-	clk_enable(wdev->mpu_wdt_fck);
+	if (wdev->omap_wdt_state & (1 << OMAP_WDT_STATE_ACTIVATED_BIT))
+		omap_wdt_ping(wdev);
+	else {
+		clk_enable(wdev->mpu_wdt_fck);
 
-	/* initialize prescaler */
-	while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01)
-		cpu_relax();
+		/* initialize prescaler */
+		while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01)
+			cpu_relax();
 
-	__raw_writel((1 << 5) | (PTV << 2), base + OMAP_WATCHDOG_CNTRL);
-	while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01)
-		cpu_relax();
+		__raw_writel((1 << 5) | (PTV << 2), base + OMAP_WATCHDOG_CNTRL);
+		while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01)
+			cpu_relax();
+		wdev->omap_wdt_state |= (1 << OMAP_WDT_STATE_ACTIVATED_BIT);
+	}
 
 	file->private_data = (void *) wdev;
 
@@ -189,10 +198,13 @@ static int omap_wdt_release(struct inode *inode, struct file *file)
 	omap_wdt_ick_enable(wdev->mpu_wdt_ick, 0);
 
 	clk_disable(wdev->mpu_wdt_fck);
+	wdev->omap_wdt_state &= ~(1 << OMAP_WDT_STATE_ACTIVATED_BIT);
 #else
+	/* Give the user application some time to recover in case of crash. */
+	omap_wdt_ping(wdev);
 	printk(KERN_CRIT "omap_wdt: Unexpected close, not stopping!\n");
 #endif
-	wdev->omap_wdt_users = 0;
+	wdev->omap_wdt_state &= ~(1 << OMAP_WDT_STATE_OPENED_BIT);
 
 	return 0;
 }
@@ -307,7 +319,7 @@ static int __init omap_wdt_probe(struct platform_device *pdev)
 		goto err_kzalloc;
 	}
 
-	wdev->omap_wdt_users = 0;
+	wdev->omap_wdt_state = 0;
 	wdev->mem = mem;
 
 	if (cpu_is_omap16xx()) {
@@ -417,7 +429,7 @@ static void omap_wdt_shutdown(struct platform_device *pdev)
 {
 	struct omap_wdt_dev *wdev = platform_get_drvdata(pdev);
 
-	if (wdev->omap_wdt_users) {
+	if (wdev->omap_wdt_state & (1<<OMAP_WDT_STATE_ACTIVATED_BIT)) {
 		omap_wdt_ick_enable(wdev->mpu_wdt_ick, 1);
 		omap_wdt_disable(wdev);
 		omap_wdt_ick_enable(wdev->mpu_wdt_ick, 0);
@@ -465,7 +477,7 @@ static int omap_wdt_suspend(struct platform_device *pdev, pm_message_t state)
 {
 	struct omap_wdt_dev *wdev = platform_get_drvdata(pdev);
 
-	if (wdev->omap_wdt_users) {
+	if (wdev->omap_wdt_state & (1<<OMAP_WDT_STATE_ACTIVATED_BIT)) {
 		omap_wdt_ick_enable(wdev->mpu_wdt_ick, 1);
 		omap_wdt_disable(wdev);
 		omap_wdt_ick_enable(wdev->mpu_wdt_ick, 0);
@@ -478,7 +490,7 @@ static int omap_wdt_resume(struct platform_device *pdev)
 {
 	struct omap_wdt_dev *wdev = platform_get_drvdata(pdev);
 
-	if (wdev->omap_wdt_users) {
+	if (wdev->omap_wdt_state & (1<<OMAP_WDT_STATE_ACTIVATED_BIT)) {
 		omap_wdt_ick_enable(wdev->mpu_wdt_ick, 1);
 		omap_wdt_enable(wdev);
 		omap_wdt_ping(wdev);
-- 
1.5.4.3


  reply	other threads:[~2009-03-10 16:07 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-03-10 16:03 [PATCH 0/7] OMAP: watchdog driver fixes Atal Shargorodsky
2009-03-10 16:03 ` [PATCH 1/6] Remove armwdt_ck field from omap_wdt_dev structure Atal Shargorodsky
2009-03-10 16:03   ` [PATCH 2/6] Fix interface clock existance check Atal Shargorodsky
2009-03-10 16:03     ` [PATCH 3/6] Remove non-explanatory comments Atal Shargorodsky
2009-03-10 16:03       ` [PATCH 4/6] Proper interface clock management Atal Shargorodsky
2009-03-10 16:03         ` Atal Shargorodsky [this message]
2009-03-10 16:03           ` [PATCH 6/6] Changing NOWAYOUT behavior does not require kernel reconfiguration Atal Shargorodsky
2009-03-11 15:29           ` [PATCH 6/6] OMAP: omap_wdt: " Atal Shargorodsky
2009-03-11 15:29         ` [PATCH 5/6] OMAP: omap_wdt: Correct manage of activation states Atal Shargorodsky
2009-03-11 15:29       ` [PATCH 4/6] OMAP: omap_wdt: Proper interface clock management Atal Shargorodsky
2009-03-11 15:29     ` [PATCH 3/6] OMAP: omap_wdt: Remove non-explanatory comments Atal Shargorodsky
2009-03-11 15:29   ` [PATCH 2/6] OMAP: omap_wdt: Fix interface clock existence check Atal Shargorodsky
2009-03-11 16:02   ` [PATCH 1/6] OMAP: omap_wdt: Remove armwdt_ck field from omap_wdt_dev structure Tony Lindgren
2009-03-10 23:30 ` [PATCH 0/7] OMAP: watchdog driver fixes Russell King - ARM Linux
2009-03-11 15:29 [PATCH 0/6] OMAP: omap_wdt: clocks and NOWAYOUT fixes Atal Shargorodsky
2009-03-11 15:29 ` [PATCH 1/6] OMAP: omap_wdt: Remove armwdt_ck field from omap_wdt_dev structure Atal Shargorodsky

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