Am 27.03.2015 um 20:21 schrieb Javier Martinez Canillas:
Hello Krzysztof,
On 03/27/2015 05:08 PM, Krzysztof Kozlowski wrote:
After adding display power domain for Exynos5250 in commit 2d2c9a8d0a4f ("ARM: dts: add display power domain for exynos5250") the display on Chromebook Snow and others stopped working after boot.
The reason for this suggested Andrzej Hajda: the DP clock was disabled. This clock is required by Display Port and is enabled by bootloader. However when FIMD driver probing was deferred, the display power domain was turned off. This effectively reset the value of DP clock enable register.
When exynos-dp is later probed, the clock is not enabled and display is not properly configured:
exynos-dp 145b0000.dp-controller: Timeout of video streamclk ok exynos-dp 145b0000.dp-controller: unable to config video
Signed-off-by: Krzysztof Kozlowski k.kozlowski@samsung.com Reported-by: Javier Martinez Canillas javier.martinez@collabora.co.uk Fixes: 2d2c9a8d0a4f ("ARM: dts: add display power domain for exynos5250") Cc: stable@vger.kernel.org
This should fix issue reported by Javier [1][2].
I tested this patch and does indeed solves both issues I reported The exynos-dp probe deferral does not make the display to not be working and also disabling and enabling the display with:
with /sys/devices/platform/exynos-drm/graphics/fb0/blank works.
Thanks a lot for fixing this issue.
On an Exynos5250 Snow Chromebook:
Tested-by: Javier Martinez Canillas javier.martinez@collabora.co.uk
Seems to fix Spring Chromebook as well,
Tested-by: Andreas Färber afaerber@suse.de
Thanks a lot,
Andreas