Re: [PATCH 2/2] iio: accel: kxcjk1013: Add rudimentary regulator support

[Jonathan Cameron <jic23@kernel.org>]

On Sun, 13 Dec 2020 22:54:36 +0530
devajithvs <devajithvs@gmail.com> wrote:

> From: Devajith V S <devajithvs@gmail.com>
> 
> kxcjk1013 devices have VDD and VDDIO power lines. Need
> to make sure the regulators are enabled before any
> communication with kxcjk1013. This patch introduces
> vdd/vddio regulators for kxcjk1013.
> 
> Signed-off-by: Devajith V S <devajithvs@gmail.com>
Looks good to me. Trivial comment on the comment inline that I can fix
whilst applying.

I'll let this sit on the list for a little while though in case
anyone else spots something I have missed.

Thanks,

Jonathan

> ---
>  drivers/iio/accel/kxcjk-1013.c | 31 +++++++++++++++++++++++++++++++
>  1 file changed, 31 insertions(+)
> 
> diff --git a/drivers/iio/accel/kxcjk-1013.c b/drivers/iio/accel/kxcjk-1013.c
> index e92c7e676..67d3d8270 100644
> --- a/drivers/iio/accel/kxcjk-1013.c
> +++ b/drivers/iio/accel/kxcjk-1013.c
> @@ -14,6 +14,7 @@
>  #include <linux/acpi.h>
>  #include <linux/pm.h>
>  #include <linux/pm_runtime.h>
> +#include <linux/regulator/consumer.h>
>  #include <linux/iio/iio.h>
>  #include <linux/iio/sysfs.h>
>  #include <linux/iio/buffer.h>
> @@ -133,6 +134,7 @@ enum kx_acpi_type {
>  };
>  
>  struct kxcjk1013_data {
> +	struct regulator_bulk_data regulators[2];
>  	struct i2c_client *client;
>  	struct iio_trigger *dready_trig;
>  	struct iio_trigger *motion_trig;
> @@ -1300,6 +1302,13 @@ static const char *kxcjk1013_match_acpi_device(struct device *dev,
>  	return dev_name(dev);
>  }
>  
> +static void kxcjk1013_disable_regulators(void *d)
> +{
> +	struct kxcjk1013_data *data = d;
> +
> +	regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
> +}
> +
>  static int kxcjk1013_probe(struct i2c_client *client,
>  			   const struct i2c_device_id *id)
>  {
> @@ -1330,6 +1339,28 @@ static int kxcjk1013_probe(struct i2c_client *client,
>  			return ret;
>  	}
>  
> +	data->regulators[0].supply = "vdd";
> +	data->regulators[1].supply = "vddio";
> +	ret = devm_regulator_bulk_get(&client->dev, ARRAY_SIZE(data->regulators),
> +				      data->regulators);
> +	if (ret)
> +		return dev_err_probe(&client->dev, ret, "Failed to get regulators\n");
> +
> +	ret = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
> +				    data->regulators);
> +	if (ret)
> +		return ret;
> +
> +	ret = devm_add_action_or_reset(&client->dev, kxcjk1013_disable_regulators, data);
> +	if (ret)
> +		return ret;
> +
> +	/*
> +	 * A typical delay of 10ms is required for powering up
> +	 * according to the data sheets of supported chips.

Probably want to add something like "so double it to play safe."

> +	 */
> +	msleep(20);
> +
>  	if (id) {
>  		data->chipset = (enum kx_chipset)(id->driver_data);
>  		name = id->name;