Commit af54a2fb authored by Bartosz Golaszewski's avatar Bartosz Golaszewski
Browse files

gpio: TODO: add an item to track reworking the sysfs interface 



It seems there really exists the need for a simple sysfs interface that
can be easily used from minimal initramfs images that don't contain much
more than busybox. However the current interface poses a challenge to
the removal of global GPIO numberspace. Add an item that tracks
extending the existing ABI with a per-chip export/unexport attribute
pair.

Reviewed-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20250321-gpio-todo-updates-v1-6-7b38f07110ee@linaro.org


Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@linaro.org>
parent 9ff2443b

drivers/gpio/TODO

+13 −0
Original line number Diff line number Diff line
@@ -173,3 +173,16 @@ value back to the caller. 
We've now added new variants - set_rv() and set_multiple_rv() that return an

integer. Let's convert all GPIO drivers treewide to use the new callbacks,

remove the old ones and finally rename the new ones back to the old names.



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Extend the sysfs ABI to allow exporting lines by their HW offsets



The need to support the sysfs GPIO class is one of the main obstacles to

removing the global GPIO numberspace from the kernel. In order to wean users

off using global numbers from user-space, extend the existing interface with

new per-gpiochip export/unexport attributes that allow to refer to GPIOs using

their hardware offsets within the chip.



Encourage users to switch to using them and eventually remove the existing

global export/unexport attribues.