watchdog: meson: Fix the wrong value of left time
diff mbox series

Message ID 1569754429-17287-1-git-send-email-xingyu.chen@amlogic.com
State Not Applicable
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Series
  • watchdog: meson: Fix the wrong value of left time
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Commit Message

Xingyu Chen Sept. 29, 2019, 10:53 a.m. UTC
The left time value is wrong when we get it by sysfs. The left time value
should be equal to preset timeout value minus elapsed time value. According
to the Meson-GXB/GXL datasheets which can be found at [0], the timeout value
is saved to BIT[0-15] of the WATCHDOG_TCNT, and elapsed time value is saved
to BIT[16-31] of the WATCHDOG_TCNT.

[0]: http://linux-meson.com

Fixes: 683fa50f0e18 ("watchdog: Add Meson GXBB Watchdog Driver")
Signed-off-by: Xingyu Chen <xingyu.chen@amlogic.com>
---
 drivers/watchdog/meson_gxbb_wdt.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Neil Armstrong Sept. 30, 2019, 8:16 a.m. UTC | #1
On 29/09/2019 12:53, Xingyu Chen wrote:
> The left time value is wrong when we get it by sysfs. The left time value
> should be equal to preset timeout value minus elapsed time value. According
> to the Meson-GXB/GXL datasheets which can be found at [0], the timeout value
> is saved to BIT[0-15] of the WATCHDOG_TCNT, and elapsed time value is saved
> to BIT[16-31] of the WATCHDOG_TCNT.
> 
> [0]: http://linux-meson.com
> 
> Fixes: 683fa50f0e18 ("watchdog: Add Meson GXBB Watchdog Driver")
> Signed-off-by: Xingyu Chen <xingyu.chen@amlogic.com>
> ---
>  drivers/watchdog/meson_gxbb_wdt.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/watchdog/meson_gxbb_wdt.c b/drivers/watchdog/meson_gxbb_wdt.c
> index d17c1a6..5a9ca10 100644
> --- a/drivers/watchdog/meson_gxbb_wdt.c
> +++ b/drivers/watchdog/meson_gxbb_wdt.c
> @@ -89,8 +89,8 @@ static unsigned int meson_gxbb_wdt_get_timeleft(struct watchdog_device *wdt_dev)
>  
>  	reg = readl(data->reg_base + GXBB_WDT_TCNT_REG);
>  
> -	return ((reg >> GXBB_WDT_TCNT_CNT_SHIFT) -
> -		(reg & GXBB_WDT_TCNT_SETUP_MASK)) / 1000;
> +	return ((reg & GXBB_WDT_TCNT_SETUP_MASK) -
> +		(reg >> GXBB_WDT_TCNT_CNT_SHIFT)) / 1000;
>  }
>  
>  static const struct watchdog_ops meson_gxbb_wdt_ops = {
> 

Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Guenter Roeck Sept. 30, 2019, 1:12 p.m. UTC | #2
On 9/29/19 3:53 AM, Xingyu Chen wrote:
> The left time value is wrong when we get it by sysfs. The left time value
> should be equal to preset timeout value minus elapsed time value. According
> to the Meson-GXB/GXL datasheets which can be found at [0], the timeout value
> is saved to BIT[0-15] of the WATCHDOG_TCNT, and elapsed time value is saved
> to BIT[16-31] of the WATCHDOG_TCNT.
> 
> [0]: http://linux-meson.com
> 
> Fixes: 683fa50f0e18 ("watchdog: Add Meson GXBB Watchdog Driver")
> Signed-off-by: Xingyu Chen <xingyu.chen@amlogic.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
>   drivers/watchdog/meson_gxbb_wdt.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/watchdog/meson_gxbb_wdt.c b/drivers/watchdog/meson_gxbb_wdt.c
> index d17c1a6..5a9ca10 100644
> --- a/drivers/watchdog/meson_gxbb_wdt.c
> +++ b/drivers/watchdog/meson_gxbb_wdt.c
> @@ -89,8 +89,8 @@ static unsigned int meson_gxbb_wdt_get_timeleft(struct watchdog_device *wdt_dev)
>   
>   	reg = readl(data->reg_base + GXBB_WDT_TCNT_REG);
>   
> -	return ((reg >> GXBB_WDT_TCNT_CNT_SHIFT) -
> -		(reg & GXBB_WDT_TCNT_SETUP_MASK)) / 1000;
> +	return ((reg & GXBB_WDT_TCNT_SETUP_MASK) -
> +		(reg >> GXBB_WDT_TCNT_CNT_SHIFT)) / 1000;
>   }
>   
>   static const struct watchdog_ops meson_gxbb_wdt_ops = {
>
Kevin Hilman Oct. 3, 2019, 5:35 p.m. UTC | #3
Xingyu Chen <xingyu.chen@amlogic.com> writes:

> The left time value is wrong when we get it by sysfs. The left time value
> should be equal to preset timeout value minus elapsed time value. According
> to the Meson-GXB/GXL datasheets which can be found at [0], the timeout value
> is saved to BIT[0-15] of the WATCHDOG_TCNT, and elapsed time value is saved
> to BIT[16-31] of the WATCHDOG_TCNT.
>
> [0]: http://linux-meson.com
>
> Fixes: 683fa50f0e18 ("watchdog: Add Meson GXBB Watchdog Driver")
> Signed-off-by: Xingyu Chen <xingyu.chen@amlogic.com>

Reviewed-by: Kevin Hilman <khilman@baylibre.com>

Patch
diff mbox series

diff --git a/drivers/watchdog/meson_gxbb_wdt.c b/drivers/watchdog/meson_gxbb_wdt.c
index d17c1a6..5a9ca10 100644
--- a/drivers/watchdog/meson_gxbb_wdt.c
+++ b/drivers/watchdog/meson_gxbb_wdt.c
@@ -89,8 +89,8 @@  static unsigned int meson_gxbb_wdt_get_timeleft(struct watchdog_device *wdt_dev)
 
 	reg = readl(data->reg_base + GXBB_WDT_TCNT_REG);
 
-	return ((reg >> GXBB_WDT_TCNT_CNT_SHIFT) -
-		(reg & GXBB_WDT_TCNT_SETUP_MASK)) / 1000;
+	return ((reg & GXBB_WDT_TCNT_SETUP_MASK) -
+		(reg >> GXBB_WDT_TCNT_CNT_SHIFT)) / 1000;
 }
 
 static const struct watchdog_ops meson_gxbb_wdt_ops = {