]> www.infradead.org Git - users/jedix/linux-maple.git/commit
gpio: TODO: add item about GPIO drivers reading struct gpio_chip::base
authorAhmad Fatoum <a.fatoum@pengutronix.de>
Wed, 7 May 2025 17:28:01 +0000 (19:28 +0200)
committerBartosz Golaszewski <bartosz.golaszewski@linaro.org>
Thu, 15 May 2025 15:00:22 +0000 (17:00 +0200)
commit833c086f22ecebe576af42051733796d1690dd71
tree3ec186f826fc6d26f46a73a4e544f8d0155302ae
parent0a45c1a002705c8622738fbd2a2913acf886ea27
gpio: TODO: add item about GPIO drivers reading struct gpio_chip::base

drivers/pinctrl/pinctrl-at91.c uses struct gpio_chip::base to find out
which bit to set in a register:

  dev_dbg(npct->dev, "enable pin %u as GPIO\n", offset);

  mask = 1 << (offset - chip->base);

This adds a non-obvious dependency on the global numberspace from the
GPIO driver itself, even if all consumers use the descriptor API.

More such instances may exist and will need to be fixed in the quest for
removal of the global numberspace, so add a reminder about it to the
TODO list.

Link: https://lore.kernel.org/all/1d00c056-3d61-4c22-bedd-3bae0bf1ddc4@pengutronix.de/
Suggested-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Link: https://lore.kernel.org/r/20250507-gpio-chip-base-readback-v1-1-ade56e38480b@pengutronix.de
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
drivers/gpio/TODO