The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From b16bef60a9112b1e6daf3afd16484eb06e7ce792 Mon Sep 17 00:00:00 2001

From: Krzysztof Kozlowski krzysztof.kozlowski@canonical.com Date: Fri, 8 Oct 2021 13:37:13 +0200 Subject: [PATCH] regulator: s5m8767: do not use reset value as DVS voltage if GPIO DVS is disabled

The driver and its bindings, before commit 04f9f068a619 ("regulator: s5m8767: Modify parsing method of the voltage table of buck2/3/4") were requiring to provide at least one safe/default voltage for DVS registers if DVS GPIO is not being enabled.

IOW, if s5m8767,pmic-buck2-uses-gpio-dvs is missing, the s5m8767,pmic-buck2-dvs-voltage should still be present and contain one voltage.

This requirement was coming from driver behavior matching this condition (none of DVS GPIO is enabled): it was always initializing the DVS selector pins to 0 and keeping the DVS enable setting at reset value (enabled). Therefore if none of DVS GPIO is enabled in devicetree, driver was configuring the first DVS voltage for buck[234].

Mentioned commit 04f9f068a619 ("regulator: s5m8767: Modify parsing method of the voltage table of buck2/3/4") broke it because DVS voltage won't be parsed from devicetree if DVS GPIO is not enabled. After the change, driver will configure bucks to use the register reset value as voltage which might have unpleasant effects.

Fix this by relaxing the bindings constrain: if DVS GPIO is not enabled in devicetree (therefore DVS voltage is also not parsed), explicitly disable it.

Cc: stable@vger.kernel.org Fixes: 04f9f068a619 ("regulator: s5m8767: Modify parsing method of the voltage table of buck2/3/4") Signed-off-by: Krzysztof Kozlowski krzysztof.kozlowski@canonical.com Acked-by: Rob Herring robh@kernel.org Message-Id: 20211008113723.134648-2-krzysztof.kozlowski@canonical.com Signed-off-by: Mark Brown broonie@kernel.org

diff --git a/Documentation/devicetree/bindings/regulator/samsung,s5m8767.txt b/Documentation/devicetree/bindings/regulator/samsung,s5m8767.txt index 093edda0c8df..d9cff1614f7a 100644 --- a/Documentation/devicetree/bindings/regulator/samsung,s5m8767.txt +++ b/Documentation/devicetree/bindings/regulator/samsung,s5m8767.txt @@ -13,6 +13,14 @@ common regulator binding documented in:

Required properties of the main device node (the parent!): + - s5m8767,pmic-buck-ds-gpios: GPIO specifiers for three host gpio's used + for selecting GPIO DVS lines. It is one-to-one mapped to dvs gpio lines. + + [1] If either of the 's5m8767,pmic-buck[2/3/4]-uses-gpio-dvs' optional + property is specified, then all the eight voltage values for the + 's5m8767,pmic-buck[2/3/4]-dvs-voltage' should be specified. + +Optional properties of the main device node (the parent!): - s5m8767,pmic-buck2-dvs-voltage: A set of 8 voltage values in micro-volt (uV) units for buck2 when changing voltage using gpio dvs. Refer to [1] below for additional information. @@ -25,19 +33,6 @@ Required properties of the main device node (the parent!): units for buck4 when changing voltage using gpio dvs. Refer to [1] below for additional information.

- - s5m8767,pmic-buck-ds-gpios: GPIO specifiers for three host gpio's used - for selecting GPIO DVS lines. It is one-to-one mapped to dvs gpio lines. - - [1] If none of the 's5m8767,pmic-buck[2/3/4]-uses-gpio-dvs' optional - property is specified, the 's5m8767,pmic-buck[2/3/4]-dvs-voltage' - property should specify atleast one voltage level (which would be a - safe operating voltage). - - If either of the 's5m8767,pmic-buck[2/3/4]-uses-gpio-dvs' optional - property is specified, then all the eight voltage values for the - 's5m8767,pmic-buck[2/3/4]-dvs-voltage' should be specified. - -Optional properties of the main device node (the parent!): - s5m8767,pmic-buck2-uses-gpio-dvs: 'buck2' can be controlled by gpio dvs. - s5m8767,pmic-buck3-uses-gpio-dvs: 'buck3' can be controlled by gpio dvs. - s5m8767,pmic-buck4-uses-gpio-dvs: 'buck4' can be controlled by gpio dvs. diff --git a/drivers/regulator/s5m8767.c b/drivers/regulator/s5m8767.c index 7c111bbdc2af..35269f998210 100644 --- a/drivers/regulator/s5m8767.c +++ b/drivers/regulator/s5m8767.c @@ -850,18 +850,15 @@ static int s5m8767_pmic_probe(struct platform_device *pdev) /* DS4 GPIO */ gpio_direction_output(pdata->buck_ds[2], 0x0);

- if (pdata->buck2_gpiodvs || pdata->buck3_gpiodvs || - pdata->buck4_gpiodvs) { - regmap_update_bits(s5m8767->iodev->regmap_pmic, - S5M8767_REG_BUCK2CTRL, 1 << 1, - (pdata->buck2_gpiodvs) ? (1 << 1) : (0 << 1)); - regmap_update_bits(s5m8767->iodev->regmap_pmic, - S5M8767_REG_BUCK3CTRL, 1 << 1, - (pdata->buck3_gpiodvs) ? (1 << 1) : (0 << 1)); - regmap_update_bits(s5m8767->iodev->regmap_pmic, - S5M8767_REG_BUCK4CTRL, 1 << 1, - (pdata->buck4_gpiodvs) ? (1 << 1) : (0 << 1)); - } + regmap_update_bits(s5m8767->iodev->regmap_pmic, + S5M8767_REG_BUCK2CTRL, 1 << 1, + (pdata->buck2_gpiodvs) ? (1 << 1) : (0 << 1)); + regmap_update_bits(s5m8767->iodev->regmap_pmic, + S5M8767_REG_BUCK3CTRL, 1 << 1, + (pdata->buck3_gpiodvs) ? (1 << 1) : (0 << 1)); + regmap_update_bits(s5m8767->iodev->regmap_pmic, + S5M8767_REG_BUCK4CTRL, 1 << 1, + (pdata->buck4_gpiodvs) ? (1 << 1) : (0 << 1));

/* Initialize GPIO DVS registers */ for (i = 0; i < 8; i++) {