Re: [linux-sunxi] Re: [PATCH 4/7] touchscreen: pixcir_i2c: Add support for wake and enable gpios

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 20-11-15 18:27, Dmitry Torokhov wrote:
> On Fri, Nov 20, 2015 at 12:17:10PM +0100, Hans de Goede wrote:
>> From: Sander Vermin <sander@vermin.nl>
>>
>> On some devices the wake and enable pins of the pixcir touchscreen
>> controller are connected to gpios and these must be controlled by the
>> driver for the device to operate properly.
>>
>> Signed-off-by: Sander Vermin <sander@vermin.nl>
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>> ---
>> Changes in v2 (Hans de Goede):
>> -Split the changes for dealing with inverted / swapped axis out into a
>>   separate patch
>> -Remove a bunch of dev_info calls to make the driver less chatty
>> -Use devm_gpiod_get_optional as these new gpios are optional
>> -Only msleep after setting enable high if we have an enable pin
>> ---
>>   .../bindings/input/touchscreen/pixcir_i2c_ts.txt   |  2 +
>>   drivers/input/touchscreen/pixcir_i2c_ts.c          | 46 ++++++++++++++++++++++
>>   2 files changed, 48 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/input/touchscreen/pixcir_i2c_ts.txt b/Documentation/devicetree/bindings/input/touchscreen/pixcir_i2c_ts.txt
>> index 8eb240a..72ca5ec 100644
>> --- a/Documentation/devicetree/bindings/input/touchscreen/pixcir_i2c_ts.txt
>> +++ b/Documentation/devicetree/bindings/input/touchscreen/pixcir_i2c_ts.txt
>> @@ -10,6 +10,8 @@ Required properties:
>>
>>   Optional properties:
>>   - reset-gpio: GPIO connected to the RESET line of the chip
>> +- enable-gpios: GPIO connected to the ENABLE line of the chip
>> +- wake-gpios: GPIO connected to the WAKE line of the chip
>>
>>   Example:
>>
>> diff --git a/drivers/input/touchscreen/pixcir_i2c_ts.c b/drivers/input/touchscreen/pixcir_i2c_ts.c
>> index 211408c..b75ef65 100644
>> --- a/drivers/input/touchscreen/pixcir_i2c_ts.c
>> +++ b/drivers/input/touchscreen/pixcir_i2c_ts.c
>> @@ -38,6 +38,8 @@ struct pixcir_i2c_ts_data {
>>   	struct input_dev *input;
>>   	struct gpio_desc *gpio_attb;
>>   	struct gpio_desc *gpio_reset;
>> +	struct gpio_desc *gpio_enable;
>> +	struct gpio_desc *gpio_wake;
>>   	const struct pixcir_i2c_chip_data *chip;
>>   	int max_fingers;	/* Max fingers supported in this instance */
>>   	bool running;
>> @@ -208,6 +210,11 @@ static int pixcir_set_power_mode(struct pixcir_i2c_ts_data *ts,
>>   	struct device *dev = &ts->client->dev;
>>   	int ret;
>>
>> +	if (mode == PIXCIR_POWER_ACTIVE || mode == PIXCIR_POWER_IDLE) {
>> +		if (!IS_ERR_OR_NULL(ts->gpio_wake))
>> +			gpiod_set_value_cansleep(ts->gpio_wake, 1);
>
> I believe you error out in case when IS_ERR(ts->gpio_wake) is true, so I
> wonder if we should simply use
>
> 		if (ts->gpio_wake)
> 			gpiod_set_value_cansleep(ts->gpio_wake, 1);
>
> here and elsewhere.

Yes that will work fine, I believe Sander went with his version because that
is what the existing gpio code (for the also optional reset pin) already does.

So from a consistency pov it is better to keep this patch as is.

> No need to resubmit, just let me know.

Ok, either way is fine with me.

Regards,

Hans