2017-09-25 05:26:50

by Oleksij Rempel

Subject: [PATCH v3 1/2] watchdog: dw_wdt: add stop watchdog operation

From: Steffen Trumtrar <[email protected]>

The only way of stopping the watchdog is by resetting it.
Add the watchdog op for stopping the device and reset if
a reset line is provided.

Signed-off-by: Steffen Trumtrar <[email protected]>
Signed-off-by: Oleksij Rempel <[email protected]>
Cc: Wim Van Sebroeck <[email protected]>
Cc: Guenter Roeck <[email protected]>
Cc: [email protected]
---

changes v3:
- don't return error if rst is not present and set WDOG_HW_RUNNING bit
to notify watchdog core.

changes v2:
- test if dw_wdt->rst is NULL instead of IS_ERR

drivers/watchdog/dw_wdt.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)

diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c
index 36be987ff9ef..6cc56b18ee52 100644
--- a/drivers/watchdog/dw_wdt.c
+++ b/drivers/watchdog/dw_wdt.c
@@ -135,6 +135,21 @@ static int dw_wdt_start(struct watchdog_device *wdd)
return 0;
}

+static int dw_wdt_stop(struct watchdog_device *wdd)
+{
+ struct dw_wdt *dw_wdt = to_dw_wdt(wdd);
+
+ if (!dw_wdt->rst) {
+ set_bit(WDOG_HW_RUNNING, &wdd->status);
+ return 0;
+ }
+
+ reset_control_assert(dw_wdt->rst);
+ reset_control_deassert(dw_wdt->rst);
+
+ return 0;
+}
+
static int dw_wdt_restart(struct watchdog_device *wdd,
unsigned long action, void *data)
{
@@ -173,6 +188,7 @@ static const struct watchdog_info dw_wdt_ident = {
static const struct watchdog_ops dw_wdt_ops = {
.owner = THIS_MODULE,
.start = dw_wdt_start,
+ .stop = dw_wdt_stop,
.ping = dw_wdt_ping,
.set_timeout = dw_wdt_set_timeout,
.get_timeleft = dw_wdt_get_timeleft,
--
2.11.0

2017-09-25 05:26:23

by Oleksij Rempel

Subject: [PATCH v3 2/2] ARM: socfpga: dtsi: add dw-wdt reset lines

From: Steffen Trumtrar <[email protected]>

Signed-off-by: Steffen Trumtrar <[email protected]>
Signed-off-by: Oleksij Rempel <[email protected]>
Cc: Dinh Nguyen <[email protected]>
Cc: [email protected]
---

no changes since version v1

arch/arm/boot/dts/socfpga.dtsi | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/arm/boot/dts/socfpga.dtsi b/arch/arm/boot/dts/socfpga.dtsi
index 7e24dc8e82d4..6e49cee084b8 100644
--- a/arch/arm/boot/dts/socfpga.dtsi
+++ b/arch/arm/boot/dts/socfpga.dtsi
@@ -924,6 +924,7 @@
reg = <0xffd02000 0x1000>;
interrupts = <0 171 4>;
clocks = <&osc1>;
+ resets = <&rst L4WD0_RESET>;
status = "disabled";
};

@@ -932,6 +933,7 @@
reg = <0xffd03000 0x1000>;
interrupts = <0 172 4>;
clocks = <&osc1>;
+ resets = <&rst L4WD1_RESET>;
status = "disabled";
};
};
--
2.11.0

2017-09-25 16:16:49

by Guenter Roeck

Subject: Re: [PATCH v3 1/2] watchdog: dw_wdt: add stop watchdog operation

On Mon, Sep 25, 2017 at 07:25:30AM +0200, Oleksij Rempel wrote:
> From: Steffen Trumtrar <[email protected]>
>
> The only way of stopping the watchdog is by resetting it.
> Add the watchdog op for stopping the device and reset if
> a reset line is provided.
>
> Signed-off-by: Steffen Trumtrar <[email protected]>
> Signed-off-by: Oleksij Rempel <[email protected]>
> Cc: Wim Van Sebroeck <[email protected]>
> Cc: Guenter Roeck <[email protected]>
> Cc: [email protected]
> ---
>
> changes v3:
> - don't return error if rst is not present and set WDOG_HW_RUNNING bit
> to notify watchdog core.
>
> changes v2:
> - test if dw_wdt->rst is NULL instead of IS_ERR
>
> drivers/watchdog/dw_wdt.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c
> index 36be987ff9ef..6cc56b18ee52 100644
> --- a/drivers/watchdog/dw_wdt.c
> +++ b/drivers/watchdog/dw_wdt.c
> @@ -135,6 +135,21 @@ static int dw_wdt_start(struct watchdog_device *wdd)
> return 0;
> }
>
> +static int dw_wdt_stop(struct watchdog_device *wdd)
> +{
> + struct dw_wdt *dw_wdt = to_dw_wdt(wdd);
> +
> + if (!dw_wdt->rst) {
> + set_bit(WDOG_HW_RUNNING, &wdd->status);

Setting WDOG_HW_RUNNING should be dropped from dw_wdt_start().

Guenter

> + return 0;
> + }
> +
> + reset_control_assert(dw_wdt->rst);
> + reset_control_deassert(dw_wdt->rst);
> +
> + return 0;
> +}
> +
> static int dw_wdt_restart(struct watchdog_device *wdd,
> unsigned long action, void *data)
> {
> @@ -173,6 +188,7 @@ static const struct watchdog_info dw_wdt_ident = {
> static const struct watchdog_ops dw_wdt_ops = {
> .owner = THIS_MODULE,
> .start = dw_wdt_start,
> + .stop = dw_wdt_stop,
> .ping = dw_wdt_ping,
> .set_timeout = dw_wdt_set_timeout,
> .get_timeleft = dw_wdt_get_timeleft,
> --
> 2.11.0
>

2017-09-26 05:17:36

by Oleksij Rempel

Subject: Re: [PATCH v3 1/2] watchdog: dw_wdt: add stop watchdog operation

Hi,

On 25.09.2017 18:16, Guenter Roeck wrote:
> On Mon, Sep 25, 2017 at 07:25:30AM +0200, Oleksij Rempel wrote:
>> From: Steffen Trumtrar <[email protected]>
>>
>> The only way of stopping the watchdog is by resetting it.
>> Add the watchdog op for stopping the device and reset if
>> a reset line is provided.
>>
>> Signed-off-by: Steffen Trumtrar <[email protected]>
>> Signed-off-by: Oleksij Rempel <[email protected]>
>> Cc: Wim Van Sebroeck <[email protected]>
>> Cc: Guenter Roeck <[email protected]>
>> Cc: [email protected]
>> ---
>>
>> changes v3:
>> - don't return error if rst is not present and set WDOG_HW_RUNNING bit
>> to notify watchdog core.
>>
>> changes v2:
>> - test if dw_wdt->rst is NULL instead of IS_ERR
>>
>> drivers/watchdog/dw_wdt.c | 16 ++++++++++++++++
>> 1 file changed, 16 insertions(+)
>>
>> diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c
>> index 36be987ff9ef..6cc56b18ee52 100644
>> --- a/drivers/watchdog/dw_wdt.c
>> +++ b/drivers/watchdog/dw_wdt.c
>> @@ -135,6 +135,21 @@ static int dw_wdt_start(struct watchdog_device *wdd)
>> return 0;
>> }
>>
>> +static int dw_wdt_stop(struct watchdog_device *wdd)
>> +{
>> + struct dw_wdt *dw_wdt = to_dw_wdt(wdd);
>> +
>> + if (!dw_wdt->rst) {
>> + set_bit(WDOG_HW_RUNNING, &wdd->status);
>
> Setting WDOG_HW_RUNNING should be dropped from dw_wdt_start().

you mean, this patch is OK, and i need to provide one more which is
removing WDOG_HW_RUNNING from dw_wdt_start(). Correct?

Regards,
Oleksij

2017-09-26 07:06:52

by Guenter Roeck

Subject: Re: [PATCH v3 1/2] watchdog: dw_wdt: add stop watchdog operation

On 09/25/2017 10:17 PM, Oleksij Rempel wrote:
> Hi,
>
> On 25.09.2017 18:16, Guenter Roeck wrote:
>> On Mon, Sep 25, 2017 at 07:25:30AM +0200, Oleksij Rempel wrote:
>>> From: Steffen Trumtrar <[email protected]>
>>>
>>> The only way of stopping the watchdog is by resetting it.
>>> Add the watchdog op for stopping the device and reset if
>>> a reset line is provided.
>>>
>>> Signed-off-by: Steffen Trumtrar <[email protected]>
>>> Signed-off-by: Oleksij Rempel <[email protected]>
>>> Cc: Wim Van Sebroeck <[email protected]>
>>> Cc: Guenter Roeck <[email protected]>
>>> Cc: [email protected]
>>> ---
>>>
>>> changes v3:
>>>   - don't return error if rst is not present and set WDOG_HW_RUNNING bit
>>>     to notify watchdog core.
>>>
>>> changes v2:
>>>   - test if dw_wdt->rst is NULL instead of IS_ERR
>>>
>>>   drivers/watchdog/dw_wdt.c | 16 ++++++++++++++++
>>>   1 file changed, 16 insertions(+)
>>>
>>> diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c
>>> index 36be987ff9ef..6cc56b18ee52 100644
>>> --- a/drivers/watchdog/dw_wdt.c
>>> +++ b/drivers/watchdog/dw_wdt.c
>>> @@ -135,6 +135,21 @@ static int dw_wdt_start(struct watchdog_device *wdd)
>>>       return 0;
>>>   }
>>> +static int dw_wdt_stop(struct watchdog_device *wdd)
>>> +{
>>> +    struct dw_wdt *dw_wdt = to_dw_wdt(wdd);
>>> +
>>> +    if (!dw_wdt->rst) {
>>> +        set_bit(WDOG_HW_RUNNING, &wdd->status);
>>
>> Setting WDOG_HW_RUNNING should be dropped from dw_wdt_start().
>
> you mean, this patch is OK, and i need to provide one more which is removing WDOG_HW_RUNNING from dw_wdt_start(). Correct?
>

No. You are providing a stop function, thus the start function should not set the flag.

Guenter