6.13-stable review patch. If anyone has any objections, please let me know.
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From: Hugo Villeneuve hvilleneuve@dimonoff.com
commit a8972d5a49b408248294b5ecbdd0a085e4726349 upstream.
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@h... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/panel/panel-jadard-jd9365da-h3.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/gpu/drm/panel/panel-jadard-jd9365da-h3.c +++ b/drivers/gpu/drm/panel/panel-jadard-jd9365da-h3.c @@ -109,13 +109,13 @@ static int jadard_prepare(struct drm_pan if (jadard->desc->lp11_to_reset_delay_ms) msleep(jadard->desc->lp11_to_reset_delay_ms);
- gpiod_set_value(jadard->reset, 1); + gpiod_set_value(jadard->reset, 0); msleep(5);
- gpiod_set_value(jadard->reset, 0); + gpiod_set_value(jadard->reset, 1); msleep(10);
- gpiod_set_value(jadard->reset, 1); + gpiod_set_value(jadard->reset, 0); msleep(130);
ret = jadard->desc->init(jadard); @@ -1130,7 +1130,7 @@ static int jadard_dsi_probe(struct mipi_ dsi->format = desc->format; dsi->lanes = desc->lanes;
- jadard->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW); + jadard->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); if (IS_ERR(jadard->reset)) { DRM_DEV_ERROR(&dsi->dev, "failed to get our reset GPIO\n"); return PTR_ERR(jadard->reset);