[PATCH 0/5] Make gpio_keys accept board descriptors
Dmitry Torokhov
dmitry.torokhov at gmail.com
Sat Nov 25 15:33:24 PST 2017
Hi Linus,
On Fri, Nov 24, 2017 at 10:30:40AM +0100, Linus Walleij wrote:
> The goal I'm working toward is to rid the kernel of the global
> GPIO numberspace.
>
> This means GPIO lines should be references by the local offset
> on the GPIO chip.
>
> This patch set starts to move gpio_keys toward using GPIO
> look-up tables instead of global GPIO numbers to find their
> GPIOs.
>
> As an example I did (I think) the necessary patches to
> convert DaVinci and i.MX to use this. There are several users
> also x86 platform devices.
>
> Strategy:
>
> - Merge the patch to input/keyboard/gpio_keys* to support
> using descriptors from board files.
>
> - Refactor the whole universe to get proper names on GPIO
> chips, and reference the GPIO lines with local offsets using
> tables, as in the example patches in this series. These
> can trickle in after the first patch is merged in Input.
> The work to be done can be seen if you type:
> git grep gpio_keys_platform_data
>
> - When all are refactored, remove the "gpio" and "active low"
> members from the platform data and delete the associated
> legacy GPIO handling in the input driver for gpio_keys.
>
> Posting this with the examples to get buy-in from Dmitry
> before I go and spend time refactoring the world.
I think this is a worthy goal, but I wonder if we could get static GPIO
descriptors work with fwnode_get_named_gpiod() so we could retire the
platform data parsing altogether. We'd need to extend static device
properties to have notion of children though.
Thanks.
--
Dmitry
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