]> git.ipfire.org Git - thirdparty/linux.git/commit
drm: panel: jd9365da-h3: fix reset signal polarity
authorHugo Villeneuve <hvilleneuve@dimonoff.com>
Fri, 27 Sep 2024 13:53:05 +0000 (09:53 -0400)
committerNeil Armstrong <neil.armstrong@linaro.org>
Thu, 13 Feb 2025 16:46:51 +0000 (17:46 +0100)
commita8972d5a49b408248294b5ecbdd0a085e4726349
treea56cb5e140b8fbdfa2277ce9b9b7245f4031ab57
parente00a2e5d485faf53c7a24b9d1b575a642227947f
drm: panel: jd9365da-h3: fix reset signal polarity

In jadard_prepare() a reset pulse is generated with the following
statements (delays ommited for clarity):

    gpiod_set_value(jadard->reset, 1); --> Deassert reset
    gpiod_set_value(jadard->reset, 0); --> Assert reset for 10ms
    gpiod_set_value(jadard->reset, 1); --> Deassert reset

However, specifying second argument of "0" to gpiod_set_value() means to
deassert the GPIO, and "1" means to assert it. If the reset signal is
defined as GPIO_ACTIVE_LOW in the DTS, the above statements will
incorrectly generate the reset pulse (inverted) and leave it asserted
(LOW) at the end of jadard_prepare().

Fix reset behavior by inverting gpiod_set_value() second argument
in jadard_prepare(). Also modify second argument to devm_gpiod_get()
in jadard_dsi_probe() to assert the reset when probing.

Do not modify it in jadard_unprepare() as it is already properly
asserted with "1", which seems to be the intended behavior.

Fixes: 6b818c533dd8 ("drm: panel: Add Jadard JD9365DA-H3 DSI panel")
Cc: stable@vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20240927135306.857617-1-hugo@hugovil.com
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240927135306.857617-1-hugo@hugovil.com
drivers/gpu/drm/panel/panel-jadard-jd9365da-h3.c