Re: [PATCH 1/2] iio: humidity: hts221: add vdd voltage regulator

[Jonathan Cameron <jic23@kernel.org>]

On Thu, 19 Nov 2020 10:13:34 +0100
Lorenzo Bianconi <lorenzo@kernel.org> wrote:

> Like all other ST sensors, hts221 devices have VDD power line.
> Introduce VDD voltage regulator to control it.
> 
> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Hi Lorenzo,

Minor thing about not printing error message is the deferred case.
Otherwise, looks good to me

Thanks,

Jonathan

> ---
>  drivers/iio/humidity/hts221.h      |  2 ++
>  drivers/iio/humidity/hts221_core.c | 39 ++++++++++++++++++++++++++++++
>  2 files changed, 41 insertions(+)
> 
> diff --git a/drivers/iio/humidity/hts221.h b/drivers/iio/humidity/hts221.h
> index 721359e226cb..cf3d8d2dccd6 100644
> --- a/drivers/iio/humidity/hts221.h
> +++ b/drivers/iio/humidity/hts221.h
> @@ -13,6 +13,7 @@
>  #define HTS221_DEV_NAME		"hts221"
>  
>  #include <linux/iio/iio.h>
> +#include <linux/regulator/consumer.h>
>  
>  enum hts221_sensor_type {
>  	HTS221_SENSOR_H,
> @@ -29,6 +30,7 @@ struct hts221_hw {
>  	const char *name;
>  	struct device *dev;
>  	struct regmap *regmap;
> +	struct regulator *vdd;
>  
>  	struct iio_trigger *trig;
>  	int irq;
> diff --git a/drivers/iio/humidity/hts221_core.c b/drivers/iio/humidity/hts221_core.c
> index 16657789dc45..e1aa99dcf142 100644
> --- a/drivers/iio/humidity/hts221_core.c
> +++ b/drivers/iio/humidity/hts221_core.c
> @@ -547,6 +547,37 @@ static const struct iio_info hts221_info = {
>  
>  static const unsigned long hts221_scan_masks[] = {0x3, 0x0};
>  
> +static int hts221_init_regulators(struct device *dev)
> +{
> +	struct iio_dev *iio_dev = dev_get_drvdata(dev);
> +	struct hts221_hw *hw = iio_priv(iio_dev);
> +	int err;
> +
> +	hw->vdd = devm_regulator_get(dev, "vdd");
> +	if (IS_ERR(hw->vdd)) {
> +		dev_err(dev, "failed to get vdd regulator: %ld\n",
> +			PTR_ERR(hw->vdd));

dev_err_probe on this as I would assume we want to not print the message
on deferred response.

> +		return PTR_ERR(hw->vdd);
> +	}
> +
> +	err = regulator_enable(hw->vdd);
> +	if (err) {
> +		dev_err(dev, "failed to enable vdd regulator: %d\n", err);
> +		return err;
> +	}
> +
> +	msleep(50);
> +
> +	return 0;
> +}
> +
> +static void hts221_chip_uninit(void *data)
> +{
> +	struct hts221_hw *hw = data;
> +
> +	regulator_disable(hw->vdd);
> +}
> +
>  int hts221_probe(struct device *dev, int irq, const char *name,
>  		 struct regmap *regmap)
>  {
> @@ -567,6 +598,14 @@ int hts221_probe(struct device *dev, int irq, const char *name,
>  	hw->irq = irq;
>  	hw->regmap = regmap;
>  
> +	err = hts221_init_regulators(dev);
> +	if (err)
> +		return err;
> +
> +	err = devm_add_action_or_reset(dev, hts221_chip_uninit, hw);
> +	if (err)
> +		return err;
> +
>  	err = hts221_check_whoami(hw);
>  	if (err < 0)
>  		return err;