[PATCH] Watchdog: mtx-1: fix abuse of gpio registers

[PATCH] Watchdog: mtx-1: fix abuse of gpio registers

[Manuel Lauss]

This patch replaces the drivers racy abuse of the gpio2 direction
register with calls to the gpio library.

Cc: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
---
 drivers/watchdog/mtx-1_wdt.c |   17 ++++++++++-------
 1 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/drivers/watchdog/mtx-1_wdt.c b/drivers/watchdog/mtx-1_wdt.c
index 5ec5ac1..011fee4 100644
--- a/drivers/watchdog/mtx-1_wdt.c
+++ b/drivers/watchdog/mtx-1_wdt.c
@@ -66,6 +66,7 @@ static struct {
 	int default_ticks;
 	unsigned long inuse;
 	unsigned gpio;
+	int gstate;
 } mtx1_wdt_device;
 
 static void mtx1_wdt_trigger(unsigned long unused)
@@ -75,13 +76,13 @@ static void mtx1_wdt_trigger(unsigned long unused)
 	spin_lock(&mtx1_wdt_device.lock);
 	if (mtx1_wdt_device.running)
 		ticks--;
-	/*
-	 * toggle GPIO2_15
-	 */
-	tmp = au_readl(GPIO2_DIR);
-	tmp = (tmp & ~(1 << mtx1_wdt_device.gpio)) |
-	      ((~tmp) & (1 << mtx1_wdt_device.gpio));
-	au_writel(tmp, GPIO2_DIR);
+
+	/* toggle wdt gpio */
+	mtx1_wdt_device.gstate = ~mtx1_wdt_device.gstate;
+	if (mtx1_wdt_device.gstate)
+		gpio_direction_output(mtx1_wdt_device.gpio, 1);
+	else
+		gpio_direction_input(mtx1_wdt_device.gpio);
 
 	if (mtx1_wdt_device.queue && ticks)
 		mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL);
@@ -103,6 +104,7 @@ static void mtx1_wdt_start(void)
 	spin_lock_irqsave(&mtx1_wdt_device.lock, flags);
 	if (!mtx1_wdt_device.queue) {
 		mtx1_wdt_device.queue = 1;
+		mtx1_wdt_device.gstate = 1;
 		gpio_set_value(mtx1_wdt_device.gpio, 1);
 		mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL);
 	}
@@ -117,6 +119,7 @@ static int mtx1_wdt_stop(void)
 	spin_lock_irqsave(&mtx1_wdt_device.lock, flags);
 	if (mtx1_wdt_device.queue) {
 		mtx1_wdt_device.queue = 0;
+		mtx1_wdt_device.gstate = 0;
 		gpio_set_value(mtx1_wdt_device.gpio, 0);
 	}
 	ticks = mtx1_wdt_device.default_ticks;
-- 
1.7.5.rc3

Re: [PATCH] Watchdog: mtx-1: fix abuse of gpio registers

[Florian Fainelli]

Hello Manuel,

On Monday 09 May 2011 21:18:34 Manuel Lauss wrote:
> This patch replaces the drivers racy abuse of the gpio2 direction
> register with calls to the gpio library.
> 
> Cc: Florian Fainelli <florian@openwrt.org>
> Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>

I will give a try at this patch, it looks good at first glance.

> ---
>  drivers/watchdog/mtx-1_wdt.c |   17 ++++++++++-------
>  1 files changed, 10 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/watchdog/mtx-1_wdt.c b/drivers/watchdog/mtx-1_wdt.c
> index 5ec5ac1..011fee4 100644
> --- a/drivers/watchdog/mtx-1_wdt.c
> +++ b/drivers/watchdog/mtx-1_wdt.c
> @@ -66,6 +66,7 @@ static struct {
>  	int default_ticks;
>  	unsigned long inuse;
>  	unsigned gpio;
> +	int gstate;
>  } mtx1_wdt_device;
> 
>  static void mtx1_wdt_trigger(unsigned long unused)
> @@ -75,13 +76,13 @@ static void mtx1_wdt_trigger(unsigned long unused)
>  	spin_lock(&mtx1_wdt_device.lock);
>  	if (mtx1_wdt_device.running)
>  		ticks--;
> -	/*
> -	 * toggle GPIO2_15
> -	 */
> -	tmp = au_readl(GPIO2_DIR);
> -	tmp = (tmp & ~(1 << mtx1_wdt_device.gpio)) |
> -	      ((~tmp) & (1 << mtx1_wdt_device.gpio));
> -	au_writel(tmp, GPIO2_DIR);
> +
> +	/* toggle wdt gpio */
> +	mtx1_wdt_device.gstate = ~mtx1_wdt_device.gstate;
> +	if (mtx1_wdt_device.gstate)
> +		gpio_direction_output(mtx1_wdt_device.gpio, 1);
> +	else
> +		gpio_direction_input(mtx1_wdt_device.gpio);
> 
>  	if (mtx1_wdt_device.queue && ticks)
>  		mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL);
> @@ -103,6 +104,7 @@ static void mtx1_wdt_start(void)
>  	spin_lock_irqsave(&mtx1_wdt_device.lock, flags);
>  	if (!mtx1_wdt_device.queue) {
>  		mtx1_wdt_device.queue = 1;
> +		mtx1_wdt_device.gstate = 1;
>  		gpio_set_value(mtx1_wdt_device.gpio, 1);
>  		mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL);
>  	}
> @@ -117,6 +119,7 @@ static int mtx1_wdt_stop(void)
>  	spin_lock_irqsave(&mtx1_wdt_device.lock, flags);
>  	if (mtx1_wdt_device.queue) {
>  		mtx1_wdt_device.queue = 0;
> +		mtx1_wdt_device.gstate = 0;
>  		gpio_set_value(mtx1_wdt_device.gpio, 0);
>  	}
>  	ticks = mtx1_wdt_device.default_ticks;

Re: [PATCH] Watchdog: mtx-1: fix abuse of gpio registers

[Manuel Lauss]

On Mon, May 9, 2011 at 9:18 PM, Manuel Lauss
<manuel.lauss@googlemail.com> wrote:
> This patch replaces the drivers racy abuse of the gpio2 direction
> register with calls to the gpio library.
>
> Cc: Florian Fainelli <florian@openwrt.org>
> Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
> ---
>  drivers/watchdog/mtx-1_wdt.c |   17 ++++++++++-------
>  1 files changed, 10 insertions(+), 7 deletions(-)

Please disregard this patch.  It depends on another change to the mtx-1
platform files, and Ralf Baechle already included it in the MIPS tree
(as part of a larger patch to the Alchemy infrastructure) for 2.6.40.

Thanks,
     Manuel Lauss
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