Re: [REGRESSION] omapdrm/N900 display broken

From: Ivaylo Dimitrov
Date: Fri Nov 27 2020 - 13:53:01 EST


Hi,

On 27.11.20 г. 19:30 ч., Tomi Valkeinen wrote:
On 27/11/2020 17:37, Ivaylo Dimitrov wrote:

With 5.9.11 and the patch on top, n900 boots fine, albeit display remains blank, could be related to
brightness, we're still investigating.

Ok. A DSS regdump for a working version and the latest one would be good too. There's a omapdss
debugfs dir, with dss, dispc and clk files which are of interest here.


It turned out to be a long standing bug in the panel driver, with the bellow fix it works fine:


diff --git a/drivers/gpu/drm/panel/panel-sony-acx565akm.c b/drivers/gpu/drm/panel/panel-sony-acx565akm.c
index fc6a7e451abe..304267f7849a
--- a/drivers/gpu/drm/panel/panel-sony-acx565akm.c
+++ b/drivers/gpu/drm/panel/panel-sony-acx565akm.c
@@ -629,7 +629,7 @@ static int acx565akm_probe(struct spi_device *spi)
lcd->spi = spi;
mutex_init(&lcd->mutex);

- lcd->reset_gpio = devm_gpiod_get(&spi->dev, "reset", GPIOD_OUT_LOW);
+ lcd->reset_gpio = devm_gpiod_get(&spi->dev, "reset", GPIOD_OUT_HIGH);
if (IS_ERR(lcd->reset_gpio)) {
dev_err(&spi->dev, "failed to get reset GPIO\n");
return PTR_ERR(lcd->reset_gpio);

Proper patch will follow.

Thanks,
Ivo