Re: [PATCH 3.19.y-ckt 084/164] thermal: exynos: Fix unbalanced regulator disable on probe failure

From: Krzysztof Kozlowski
Date: Wed Dec 09 2015 - 08:24:42 EST


W dniu 03.12.2015 o 01:58, Kamal Mostafa pisze:
> 3.19.8-ckt11 -stable review patch. If anyone has any objections, please let me know.
>
> ------------------
>
> From: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
>
> commit 824ead03b78403a21449cb7eb153a4344cd3b4c8 upstream.
>
> 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.
>
> Acked-by: Lukasz Majewski <l.majewski@xxxxxxxxxxx>
> Tested-by: Lukasz Majewski <l.majewski@xxxxxxxxxxx>
> Reviewed-by: Alim Akhtar <alim.akhtar@xxxxxxxxxxx>
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
> Fixes: 5f09a5cbd14a ("thermal: exynos: Disable the regulator on probe failure")
> Signed-off-by: Eduardo Valentin <edubezval@xxxxxxxxx>
> Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
> ---
> drivers/thermal/samsung/exynos_tmu.c | 33 ++++++++++++++++-----------------
> 1 file changed, 16 insertions(+), 17 deletions(-)

This patch shouldn't be backported before 4.2. It fixes a bug introduced
in 4.2: 5f09a5cbd14a.

For kernels <4.2 this bug does not exist but fortunately the patch looks
harmless. Anyway I think that still it shouldn't be ported for <4.2.

Best regards,
Krzysztof


>
> diff --git a/drivers/thermal/samsung/exynos_tmu.c b/drivers/thermal/samsung/exynos_tmu.c
> index 7da2fdc..26f8e86 100644
> --- a/drivers/thermal/samsung/exynos_tmu.c
> +++ b/drivers/thermal/samsung/exynos_tmu.c
> @@ -729,27 +729,10 @@ 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;
> @@ -849,6 +832,22 @@ static int exynos_tmu_probe(struct platform_device *pdev)
> platform_set_drvdata(pdev, data);
> mutex_init(&data->lock);
>
> + /*
> + * 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)
> return ret;
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/