6.12-stable review patch. If anyone has any objections, please let me know.
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From: Chen-Yu Tsai wenst@chromium.org
commit c5f3f21728b069412e8072b8b1d0a3d9d3ab0265 upstream.
The IT6505 bridge chip has a active low reset line. Since it is a "reset" and not an "enable" line, the GPIO should be asserted to put it in reset and deasserted to bring it out of reset during the power on sequence.
The polarity was inverted when the driver was first introduced, likely because the device family that was targeted had an inverting level shifter on the reset line.
The MT8186 Corsola devices already have the IT6505 in their device tree, but the whole display pipeline is actually disabled and won't be enabled until some remaining issues are sorted out. The other known user is the MT8183 Kukui / Jacuzzi family; their device trees currently do not have the IT6505 included.
Fix the polarity in the driver while there are no actual users.
Fixes: b5c84a9edcd4 ("drm/bridge: add it6505 driver") Cc: stable@vger.kernel.org Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Reviewed-by: Neil Armstrong neil.armstrong@linaro.org Link: https://patchwork.freedesktop.org/patch/msgid/20241029095411.657616-1-wenst@... Signed-off-by: Chen-Yu Tsai wenst@chromium.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/bridge/ite-it6505.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/gpu/drm/bridge/ite-it6505.c +++ b/drivers/gpu/drm/bridge/ite-it6505.c @@ -2614,9 +2614,9 @@ static int it6505_poweron(struct it6505 /* time interval between OVDD and SYSRSTN at least be 10ms */ if (pdata->gpiod_reset) { usleep_range(10000, 20000); - gpiod_set_value_cansleep(pdata->gpiod_reset, 0); - usleep_range(1000, 2000); gpiod_set_value_cansleep(pdata->gpiod_reset, 1); + usleep_range(1000, 2000); + gpiod_set_value_cansleep(pdata->gpiod_reset, 0); usleep_range(25000, 35000); }
@@ -2647,7 +2647,7 @@ static int it6505_poweroff(struct it6505 disable_irq_nosync(it6505->irq);
if (pdata->gpiod_reset) - gpiod_set_value_cansleep(pdata->gpiod_reset, 0); + gpiod_set_value_cansleep(pdata->gpiod_reset, 1);
if (pdata->pwr18) { err = regulator_disable(pdata->pwr18); @@ -3135,7 +3135,7 @@ static int it6505_init_pdata(struct it65 return PTR_ERR(pdata->ovdd); }
- pdata->gpiod_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW); + pdata->gpiod_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); if (IS_ERR(pdata->gpiod_reset)) { dev_err(dev, "gpiod_reset gpio not found"); return PTR_ERR(pdata->gpiod_reset);