Re: [PATCH v4 2/4] Input: goodix - Add AVDD28-supply regulator support

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

Hi Jagan,

On Tue, Feb 12, 2019 at 04:54:37PM +0530, Jagan Teki wrote:
> Goodix CTP controllers have AVDD28 pin connected to voltage
> regulator which may not be turned on by default, like for GT5663.
> 
> Add support for such ctp used boards by adding voltage regulator
> handling code to goodix ctp driver.
> 
> Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
> ---
>  drivers/input/touchscreen/goodix.c | 44 ++++++++++++++++++++++++++----
>  1 file changed, 39 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
> index f2d9c2c41885..e92b90be1ac2 100644
> --- a/drivers/input/touchscreen/goodix.c
> +++ b/drivers/input/touchscreen/goodix.c
> @@ -27,6 +27,7 @@
>  #include <linux/delay.h>
>  #include <linux/irq.h>
>  #include <linux/interrupt.h>
> +#include <linux/regulator/consumer.h>
>  #include <linux/slab.h>
>  #include <linux/acpi.h>
>  #include <linux/of.h>
> @@ -47,6 +48,7 @@ struct goodix_ts_data {
>  	struct touchscreen_properties prop;
>  	unsigned int max_touch_num;
>  	unsigned int int_trigger_type;
> +	struct regulator *avdd28;
>  	struct gpio_desc *gpiod_int;
>  	struct gpio_desc *gpiod_rst;
>  	u16 id;
> @@ -761,6 +763,13 @@ static void goodix_config_cb(const struct firmware *cfg, void *ctx)
>  	complete_all(&ts->firmware_loading_complete);
>  }
>  
> +static void goodix_disable_regulator(void *arg)
> +{
> +	struct goodix_ts_data *ts = arg;
> +
> +	regulator_disable(ts->avdd28);
> +}
> +
>  static int goodix_ts_probe(struct i2c_client *client,
>  			   const struct i2c_device_id *id)
>  {
> @@ -786,25 +795,46 @@ static int goodix_ts_probe(struct i2c_client *client,
>  	if (error)
>  		return error;
>  
> +	ts->avdd28 = devm_regulator_get(&client->dev, "AVDD28");
> +	if (IS_ERR(ts->avdd28)) {
> +		error = PTR_ERR(ts->avdd28);
> +		if (error != -EPROBE_DEFER)
> +			dev_err(&client->dev,
> +				"Failed to get AVDD28 regulator: %d\n", error);
> +		return error;
> +	}
> +
> +	/* power the controller */
> +	error = regulator_enable(ts->avdd28);
> +	if (error) {
> +		dev_err(&client->dev, "Controller fail to enable AVDD28\n");
> +		return error;
> +	}
> +
> +	error = devm_add_action_or_reset(&client->dev,
> +					 goodix_disable_regulator, ts);
> +	if (error)
> +		return error;
> +
>  	if (ts->gpiod_int && ts->gpiod_rst) {
>  		/* reset the controller */
>  		error = goodix_reset(ts);
>  		if (error) {
>  			dev_err(&client->dev, "Controller reset failed.\n");
> -			return error;
> +			goto error;

Why are you changing this? You added goodix_disable_regulator() as
custom devm action, so it will fire if probe() returns with error.

Thanks.

-- 
Dmitry