Re: [RFT PATCHv2] drm/exynos: Enable DP clock to fix display on Exynos5250 and other

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 <redacted>
Reported-by: Javier Martinez Canillas <redacted>
Fixes: 2d2c9a8d0a4f ("ARM: dts: add display power domain for exynos5250")
Cc: <redacted>

---

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 <redacted>

Best regards,
Javier