The patch below does not apply to the 4.19-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 7685010fca2ba0284f31fd1380df3cffc96d847e Mon Sep 17 00:00:00 2001

From: Fabrice Gasnier fabrice.gasnier@st.com Date: Wed, 19 Jun 2019 14:29:55 +0200 Subject: [PATCH] iio: adc: stm32-adc: add missing vdda-supply

Add missing vdda-supply, analog power supply, to STM32 ADC. When vdda is an independent supply, it needs to be properly turned on or off to supply the ADC.

Signed-off-by: Fabrice Gasnier fabrice.gasnier@st.com Fixes: 1add69880240 ("iio: adc: Add support for STM32 ADC core"). Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com

diff --git a/drivers/iio/adc/stm32-adc-core.c b/drivers/iio/adc/stm32-adc-core.c index 2327ec18b40c..1f7ce5186dfc 100644 --- a/drivers/iio/adc/stm32-adc-core.c +++ b/drivers/iio/adc/stm32-adc-core.c @@ -87,6 +87,7 @@ struct stm32_adc_priv_cfg { * @domain: irq domain reference * @aclk: clock reference for the analog circuitry * @bclk: bus clock common for all ADCs, depends on part used + * @vdda: vdda analog supply reference * @vref: regulator reference * @cfg: compatible configuration data * @common: common data for all ADC instances @@ -97,6 +98,7 @@ struct stm32_adc_priv { struct irq_domain *domain; struct clk *aclk; struct clk *bclk; + struct regulator *vdda; struct regulator *vref; const struct stm32_adc_priv_cfg *cfg; struct stm32_adc_common common; @@ -394,10 +396,16 @@ static int stm32_adc_core_hw_start(struct device *dev) struct stm32_adc_priv *priv = to_stm32_adc_priv(common); int ret;

+ ret = regulator_enable(priv->vdda); + if (ret < 0) { + dev_err(dev, "vdda enable failed %d\n", ret); + return ret; + } + ret = regulator_enable(priv->vref); if (ret < 0) { dev_err(dev, "vref enable failed\n"); - return ret; + goto err_vdda_disable; }

if (priv->bclk) { @@ -425,6 +433,8 @@ static int stm32_adc_core_hw_start(struct device *dev) clk_disable_unprepare(priv->bclk); err_regulator_disable: regulator_disable(priv->vref); +err_vdda_disable: + regulator_disable(priv->vdda);

return ret; } @@ -441,6 +451,7 @@ static void stm32_adc_core_hw_stop(struct device *dev) if (priv->bclk) clk_disable_unprepare(priv->bclk); regulator_disable(priv->vref); + regulator_disable(priv->vdda); }

static int stm32_adc_probe(struct platform_device *pdev) @@ -468,6 +479,14 @@ static int stm32_adc_probe(struct platform_device *pdev) return PTR_ERR(priv->common.base); priv->common.phys_base = res->start;

+ priv->vdda = devm_regulator_get(&pdev->dev, "vdda"); + if (IS_ERR(priv->vdda)) { + ret = PTR_ERR(priv->vdda); + if (ret != -EPROBE_DEFER) + dev_err(&pdev->dev, "vdda get failed, %d\n", ret); + return ret; + } + priv->vref = devm_regulator_get(&pdev->dev, "vref"); if (IS_ERR(priv->vref)) { ret = PTR_ERR(priv->vref);