[PATCH 1/5] thermal: exynos: Fix unbalanced regulator disable on probe failure

[PATCH 1/5] thermal: exynos: Fix unbalanced regulator disable on probe failure

[Krzysztof Kozlowski]

During probe if the regulator could not be enabled, the error exit path
would still disable it. This could lead to unbalanced counter of
regulator enable/disable.

The patch moves code for getting and enabling the regulator from
exynos_map_dt_data() to probe function because it is really not a part
of getting Device Tree properties.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Fixes: 5f09a5cbd14a ("thermal: exynos: Disable the regulator on probe failure")
Cc: <stable@vger.kernel.org>
---
 drivers/thermal/samsung/exynos_tmu.c | 34 +++++++++++++++++-----------------
 1 file changed, 17 insertions(+), 17 deletions(-)

diff --git a/drivers/thermal/samsung/exynos_tmu.c b/drivers/thermal/samsung/exynos_tmu.c
index 0bae8cc6c23a..23f4320f8ef7 100644
--- a/drivers/thermal/samsung/exynos_tmu.c
+++ b/drivers/thermal/samsung/exynos_tmu.c
@@ -1168,27 +1168,10 @@ static int exynos_map_dt_data(struct platform_device *pdev)
 	struct exynos_tmu_data *data = platform_get_drvdata(pdev);
 	struct exynos_tmu_platform_data *pdata;
 	struct resource res;
-	int ret;
 
 	if (!data || !pdev->dev.of_node)
 		return -ENODEV;
 
-	/*
-	 * Try enabling the regulator if found
-	 * TODO: Add regulator as an SOC feature, so that regulator enable
-	 * is a compulsory call.
-	 */
-	data->regulator = devm_regulator_get(&pdev->dev, "vtmu");
-	if (!IS_ERR(data->regulator)) {
-		ret = regulator_enable(data->regulator);
-		if (ret) {
-			dev_err(&pdev->dev, "failed to enable vtmu\n");
-			return ret;
-		}
-	} else {
-		dev_info(&pdev->dev, "Regulator node (vtmu) not found\n");
-	}
-
 	data->id = of_alias_get_id(pdev->dev.of_node, "tmuctrl");
 	if (data->id < 0)
 		data->id = 0;
@@ -1312,6 +1295,23 @@ static int exynos_tmu_probe(struct platform_device *pdev)
 		pr_err("thermal: tz: %p ERROR\n", data->tzd);
 		return PTR_ERR(data->tzd);
 	}
+
+	/*
+	 * Try enabling the regulator if found
+	 * TODO: Add regulator as an SOC feature, so that regulator enable
+	 * is a compulsory call.
+	 */
+	data->regulator = devm_regulator_get(&pdev->dev, "vtmu");
+	if (!IS_ERR(data->regulator)) {
+		ret = regulator_enable(data->regulator);
+		if (ret) {
+			dev_err(&pdev->dev, "failed to enable vtmu\n");
+			return ret;
+		}
+	} else {
+		dev_info(&pdev->dev, "Regulator node (vtmu) not found\n");
+	}
+
 	ret = exynos_map_dt_data(pdev);
 	if (ret)
 		goto err_sensor;
-- 
1.9.1

Re: [PATCH 1/5] thermal: exynos: Fix unbalanced regulator disable on probe failure

[Alim Akhtar]

Hello,

On Thu, Oct 8, 2015 at 11:04 AM, Krzysztof Kozlowski
<k.kozlowski@samsung.com> wrote:
> During probe if the regulator could not be enabled, the error exit path
> would still disable it. This could lead to unbalanced counter of
> regulator enable/disable.
>
Do you see a regulator unbalanced reported here during boot? You may
want to add that to commit message.

> The patch moves code for getting and enabling the regulator from
> exynos_map_dt_data() to probe function because it is really not a part
> of getting Device Tree properties.
>
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> Fixes: 5f09a5cbd14a ("thermal: exynos: Disable the regulator on probe failure")
> Cc: <stable@vger.kernel.org>
> ---
>  drivers/thermal/samsung/exynos_tmu.c | 34 +++++++++++++++++-----------------
>  1 file changed, 17 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/thermal/samsung/exynos_tmu.c b/drivers/thermal/samsung/exynos_tmu.c
> index 0bae8cc6c23a..23f4320f8ef7 100644
> --- a/drivers/thermal/samsung/exynos_tmu.c
> +++ b/drivers/thermal/samsung/exynos_tmu.c
> @@ -1168,27 +1168,10 @@ static int exynos_map_dt_data(struct platform_device *pdev)
>         struct exynos_tmu_data *data = platform_get_drvdata(pdev);
>         struct exynos_tmu_platform_data *pdata;
>         struct resource res;
> -       int ret;
>
>         if (!data || !pdev->dev.of_node)
>                 return -ENODEV;
>
> -       /*
> -        * Try enabling the regulator if found
> -        * TODO: Add regulator as an SOC feature, so that regulator enable
> -        * is a compulsory call.
> -        */
> -       data->regulator = devm_regulator_get(&pdev->dev, "vtmu");
> -       if (!IS_ERR(data->regulator)) {
> -               ret = regulator_enable(data->regulator);
> -               if (ret) {
> -                       dev_err(&pdev->dev, "failed to enable vtmu\n");
> -                       return ret;
> -               }
> -       } else {
> -               dev_info(&pdev->dev, "Regulator node (vtmu) not found\n");
> -       }
> -
>         data->id = of_alias_get_id(pdev->dev.of_node, "tmuctrl");
>         if (data->id < 0)
>                 data->id = 0;
> @@ -1312,6 +1295,23 @@ static int exynos_tmu_probe(struct platform_device *pdev)
>                 pr_err("thermal: tz: %p ERROR\n", data->tzd);
>                 return PTR_ERR(data->tzd);
>         }
> +
> +       /*
> +        * Try enabling the regulator if found
> +        * TODO: Add regulator as an SOC feature, so that regulator enable
> +        * is a compulsory call.
> +        */
> +       data->regulator = devm_regulator_get(&pdev->dev, "vtmu");
> +       if (!IS_ERR(data->regulator)) {
> +               ret = regulator_enable(data->regulator);
> +               if (ret) {
> +                       dev_err(&pdev->dev, "failed to enable vtmu\n");
> +                       return ret;
> +               }
> +       } else {
> +               dev_info(&pdev->dev, "Regulator node (vtmu) not found\n");
> +       }
> +
>         ret = exynos_map_dt_data(pdev);
>         if (ret)
>                 goto err_sensor;
> --
> 1.9.1
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel



-- 
Regards,
Alim

Re: [PATCH 1/5] thermal: exynos: Fix unbalanced regulator disable on probe failure

[Krzysztof Kozlowski]

W dniu 09.10.2015 o 01:45, Alim Akhtar pisze:
> Hello,
> 
> On Thu, Oct 8, 2015 at 11:04 AM, Krzysztof Kozlowski
> <k.kozlowski@samsung.com> wrote:
>> During probe if the regulator could not be enabled, the error exit path
>> would still disable it. This could lead to unbalanced counter of
>> regulator enable/disable.
>>
> Do you see a regulator unbalanced reported here during boot? You may
> want to add that to commit message.

I did not see the warning/error message about unbalanced disable. It
would happen in certain condition only - no other enables of regulator
and count going below 0.

I would have to simulate this error to get the warning message. I don't
think it is worth the effort.

Best regards,
Krzysztof

> 
>> The patch moves code for getting and enabling the regulator from
>> exynos_map_dt_data() to probe function because it is really not a part
>> of getting Device Tree properties.
>>
>> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
>> Fixes: 5f09a5cbd14a ("thermal: exynos: Disable the regulator on probe failure")
>> Cc: <stable@vger.kernel.org>
>> ---
>>  drivers/thermal/samsung/exynos_tmu.c | 34 +++++++++++++++++-----------------
>>  1 file changed, 17 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/thermal/samsung/exynos_tmu.c b/drivers/thermal/samsung/exynos_tmu.c
>> index 0bae8cc6c23a..23f4320f8ef7 100644
>> --- a/drivers/thermal/samsung/exynos_tmu.c
>> +++ b/drivers/thermal/samsung/exynos_tmu.c
>> @@ -1168,27 +1168,10 @@ static int exynos_map_dt_data(struct platform_device *pdev)
>>         struct exynos_tmu_data *data = platform_get_drvdata(pdev);
>>         struct exynos_tmu_platform_data *pdata;
>>         struct resource res;
>> -       int ret;
>>
>>         if (!data || !pdev->dev.of_node)
>>                 return -ENODEV;
>>
>> -       /*
>> -        * Try enabling the regulator if found
>> -        * TODO: Add regulator as an SOC feature, so that regulator enable
>> -        * is a compulsory call.
>> -        */
>> -       data->regulator = devm_regulator_get(&pdev->dev, "vtmu");
>> -       if (!IS_ERR(data->regulator)) {
>> -               ret = regulator_enable(data->regulator);
>> -               if (ret) {
>> -                       dev_err(&pdev->dev, "failed to enable vtmu\n");
>> -                       return ret;
>> -               }
>> -       } else {
>> -               dev_info(&pdev->dev, "Regulator node (vtmu) not found\n");
>> -       }
>> -
>>         data->id = of_alias_get_id(pdev->dev.of_node, "tmuctrl");
>>         if (data->id < 0)
>>                 data->id = 0;
>> @@ -1312,6 +1295,23 @@ static int exynos_tmu_probe(struct platform_device *pdev)
>>                 pr_err("thermal: tz: %p ERROR\n", data->tzd);
>>                 return PTR_ERR(data->tzd);
>>         }
>> +
>> +       /*
>> +        * Try enabling the regulator if found
>> +        * TODO: Add regulator as an SOC feature, so that regulator enable
>> +        * is a compulsory call.
>> +        */
>> +       data->regulator = devm_regulator_get(&pdev->dev, "vtmu");
>> +       if (!IS_ERR(data->regulator)) {
>> +               ret = regulator_enable(data->regulator);
>> +               if (ret) {
>> +                       dev_err(&pdev->dev, "failed to enable vtmu\n");
>> +                       return ret;
>> +               }
>> +       } else {
>> +               dev_info(&pdev->dev, "Regulator node (vtmu) not found\n");
>> +       }
>> +
>>         ret = exynos_map_dt_data(pdev);
>>         if (ret)
>>                 goto err_sensor;
>> --
>> 1.9.1
>>
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> 
> 
> 

Re: [PATCH 1/5] thermal: exynos: Fix unbalanced regulator disable on probe failure

[Alim Akhtar]

Hello,

On Fri, Oct 9, 2015 at 4:28 PM, Krzysztof Kozlowski
<k.kozlowski@samsung.com> wrote:
> W dniu 09.10.2015 o 01:45, Alim Akhtar pisze:
>> Hello,
>>
>> On Thu, Oct 8, 2015 at 11:04 AM, Krzysztof Kozlowski
>> <k.kozlowski@samsung.com> wrote:
>>> During probe if the regulator could not be enabled, the error exit path
>>> would still disable it. This could lead to unbalanced counter of
>>> regulator enable/disable.
>>>
>> Do you see a regulator unbalanced reported here during boot? You may
>> want to add that to commit message.
>
> I did not see the warning/error message about unbalanced disable. It
> would happen in certain condition only - no other enables of regulator
> and count going below 0.
>
> I would have to simulate this error to get the warning message. I don't
> think it is worth the effort.
>
Ok, looking at code, it does looks to be calling regulator disable in
case regulator enable fails.
Feel free to add
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Thanks!!

> Best regards,
> Krzysztof
>
>>
>>> The patch moves code for getting and enabling the regulator from
>>> exynos_map_dt_data() to probe function because it is really not a part
>>> of getting Device Tree properties.
>>>
>>> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
>>> Fixes: 5f09a5cbd14a ("thermal: exynos: Disable the regulator on probe failure")
>>> Cc: <stable@vger.kernel.org>
>>> ---
>>>  drivers/thermal/samsung/exynos_tmu.c | 34 +++++++++++++++++-----------------
>>>  1 file changed, 17 insertions(+), 17 deletions(-)
>>>
>>> diff --git a/drivers/thermal/samsung/exynos_tmu.c b/drivers/thermal/samsung/exynos_tmu.c
>>> index 0bae8cc6c23a..23f4320f8ef7 100644
>>> --- a/drivers/thermal/samsung/exynos_tmu.c
>>> +++ b/drivers/thermal/samsung/exynos_tmu.c
>>> @@ -1168,27 +1168,10 @@ static int exynos_map_dt_data(struct platform_device *pdev)
>>>         struct exynos_tmu_data *data = platform_get_drvdata(pdev);
>>>         struct exynos_tmu_platform_data *pdata;
>>>         struct resource res;
>>> -       int ret;
>>>
>>>         if (!data || !pdev->dev.of_node)
>>>                 return -ENODEV;
>>>
>>> -       /*
>>> -        * Try enabling the regulator if found
>>> -        * TODO: Add regulator as an SOC feature, so that regulator enable
>>> -        * is a compulsory call.
>>> -        */
>>> -       data->regulator = devm_regulator_get(&pdev->dev, "vtmu");
>>> -       if (!IS_ERR(data->regulator)) {
>>> -               ret = regulator_enable(data->regulator);
>>> -               if (ret) {
>>> -                       dev_err(&pdev->dev, "failed to enable vtmu\n");
>>> -                       return ret;
>>> -               }
>>> -       } else {
>>> -               dev_info(&pdev->dev, "Regulator node (vtmu) not found\n");
>>> -       }
>>> -
>>>         data->id = of_alias_get_id(pdev->dev.of_node, "tmuctrl");
>>>         if (data->id < 0)
>>>                 data->id = 0;
>>> @@ -1312,6 +1295,23 @@ static int exynos_tmu_probe(struct platform_device *pdev)
>>>                 pr_err("thermal: tz: %p ERROR\n", data->tzd);
>>>                 return PTR_ERR(data->tzd);
>>>         }
>>> +
>>> +       /*
>>> +        * Try enabling the regulator if found
>>> +        * TODO: Add regulator as an SOC feature, so that regulator enable
>>> +        * is a compulsory call.
>>> +        */
>>> +       data->regulator = devm_regulator_get(&pdev->dev, "vtmu");
>>> +       if (!IS_ERR(data->regulator)) {
>>> +               ret = regulator_enable(data->regulator);
>>> +               if (ret) {
>>> +                       dev_err(&pdev->dev, "failed to enable vtmu\n");
>>> +                       return ret;
>>> +               }
>>> +       } else {
>>> +               dev_info(&pdev->dev, "Regulator node (vtmu) not found\n");
>>> +       }
>>> +
>>>         ret = exynos_map_dt_data(pdev);
>>>         if (ret)
>>>                 goto err_sensor;
>>> --
>>> 1.9.1
>>>
>>>
>>> _______________________________________________
>>> linux-arm-kernel mailing list
>>> linux-arm-kernel@lists.infradead.org
>>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>>
>>
>>
>



-- 
Regards,
Alim

Re: [PATCH 1/5] thermal: exynos: Fix unbalanced regulator disable on probe failure

[Lukasz Majewski]

Hi Alim,

> Hello,
> 
> On Fri, Oct 9, 2015 at 4:28 PM, Krzysztof Kozlowski
> <k.kozlowski@samsung.com> wrote:
> > W dniu 09.10.2015 o 01:45, Alim Akhtar pisze:
> >> Hello,
> >>
> >> On Thu, Oct 8, 2015 at 11:04 AM, Krzysztof Kozlowski
> >> <k.kozlowski@samsung.com> wrote:
> >>> During probe if the regulator could not be enabled, the error
> >>> exit path would still disable it. This could lead to unbalanced
> >>> counter of regulator enable/disable.
> >>>
> >> Do you see a regulator unbalanced reported here during boot? You
> >> may want to add that to commit message.
> >
> > I did not see the warning/error message about unbalanced disable. It
> > would happen in certain condition only - no other enables of
> > regulator and count going below 0.
> >
> > I would have to simulate this error to get the warning message. I
> > don't think it is worth the effort.
> >
> Ok, looking at code, it does looks to be calling regulator disable in
> case regulator enable fails.
> Feel free to add
> Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
> Thanks!!
> 
> > Best regards,
> > Krzysztof
> >
> >>
> >>> The patch moves code for getting and enabling the regulator from
> >>> exynos_map_dt_data() to probe function because it is really not a
> >>> part of getting Device Tree properties.
> >>>
> >>> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> >>> Fixes: 5f09a5cbd14a ("thermal: exynos: Disable the regulator on
> >>> probe failure") Cc: <stable@vger.kernel.org>
> >>> ---
> >>>  drivers/thermal/samsung/exynos_tmu.c | 34
> >>> +++++++++++++++++----------------- 1 file changed, 17
> >>> insertions(+), 17 deletions(-)
> >>>
> >>> diff --git a/drivers/thermal/samsung/exynos_tmu.c
> >>> b/drivers/thermal/samsung/exynos_tmu.c index
> >>> 0bae8cc6c23a..23f4320f8ef7 100644 ---
> >>> a/drivers/thermal/samsung/exynos_tmu.c +++
> >>> b/drivers/thermal/samsung/exynos_tmu.c @@ -1168,27 +1168,10 @@
> >>> static int exynos_map_dt_data(struct platform_device *pdev)
> >>> struct exynos_tmu_data *data = platform_get_drvdata(pdev); struct
> >>> exynos_tmu_platform_data *pdata; struct resource res;
> >>> -       int ret;
> >>>
> >>>         if (!data || !pdev->dev.of_node)
> >>>                 return -ENODEV;
> >>>
> >>> -       /*
> >>> -        * Try enabling the regulator if found
> >>> -        * TODO: Add regulator as an SOC feature, so that
> >>> regulator enable
> >>> -        * is a compulsory call.
> >>> -        */
> >>> -       data->regulator = devm_regulator_get(&pdev->dev, "vtmu");
> >>> -       if (!IS_ERR(data->regulator)) {
> >>> -               ret = regulator_enable(data->regulator);
> >>> -               if (ret) {
> >>> -                       dev_err(&pdev->dev, "failed to enable
> >>> vtmu\n");
> >>> -                       return ret;
> >>> -               }
> >>> -       } else {
> >>> -               dev_info(&pdev->dev, "Regulator node (vtmu) not
> >>> found\n");
> >>> -       }
> >>> -
> >>>         data->id = of_alias_get_id(pdev->dev.of_node, "tmuctrl");
> >>>         if (data->id < 0)
> >>>                 data->id = 0;
> >>> @@ -1312,6 +1295,23 @@ static int exynos_tmu_probe(struct
> >>> platform_device *pdev) pr_err("thermal: tz: %p ERROR\n",
> >>> data->tzd); return PTR_ERR(data->tzd);
> >>>         }
> >>> +
> >>> +       /*
> >>> +        * Try enabling the regulator if found
> >>> +        * TODO: Add regulator as an SOC feature, so that
> >>> regulator enable
> >>> +        * is a compulsory call.
> >>> +        */
> >>> +       data->regulator = devm_regulator_get(&pdev->dev, "vtmu");
> >>> +       if (!IS_ERR(data->regulator)) {
> >>> +               ret = regulator_enable(data->regulator);
> >>> +               if (ret) {
> >>> +                       dev_err(&pdev->dev, "failed to enable
> >>> vtmu\n");
> >>> +                       return ret;
> >>> +               }
> >>> +       } else {
> >>> +               dev_info(&pdev->dev, "Regulator node (vtmu) not
> >>> found\n");
> >>> +       }
> >>> +
> >>>         ret = exynos_map_dt_data(pdev);
> >>>         if (ret)
> >>>                 goto err_sensor;
> >>> --
> >>> 1.9.1
> >>>
> >>>
> >>> _______________________________________________
> >>> linux-arm-kernel mailing list
> >>> linux-arm-kernel@lists.infradead.org
> >>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> >>
> >>
> >>
> >
> 
> 
> 

Acked-by: Lukasz Majewski <l.majewski@samsung.com>
Tested-by: Lukasz Majewski <l.majewski@samsung.com>

-- 
Best regards,

Lukasz Majewski

Samsung R&D Institute Poland (SRPOL) | Linux Platform Group