Re: [PATCH v1 36/63] Input: atmel_mxt_ts - configure and use gpios as real gpios

Jiada Wang
2019-08-23T05:16:14Z

Hi Dmitry

On 2019/08/17 2:24, Dmitry Torokhov wrote:
> On Fri, Aug 16, 2019 at 05:34:58PM +0900, Jiada Wang wrote:
>> From: Kautuk Consul <kautuk_consul@mentor.com>
>>
>> The upstream Atmel mXT driver implementation seems to handle the
>> T19 GPIO/PWM object as a key pad. Keys can be defined in the
>> device tree ("linux,gpio-keymap") and will be transported as key
>> events to the Linux input device if GPIO state changes.
>>
>> With our hardware, the GPIO pins of the touch controller are
>> connected to a PWM/backlight controller and used as supervision
>> inputs. We like to read the status of the pins by a script or an
>> application in the sysfs.
>>
>> Adding newer sysfs entries which shall be placed in the input
>> class directory eg:
>> /sys/class/input/input<n>/backlight_error1
>
> No, if you want to export GPIO lines for external use create a gpiochip
> instance and register it with GPIO subsystem. No ad-hoc sysfs please.
>
Agree, I will drop this patch in v2 patch-set

Thanks,
Jiada
> Thanks.
>