[PATCH 08/22] drm/tegra: dc: Drop the reset asserts to workaround a bug

[Thierry Reding]

On Tue, May 23, 2017 at 03:14:23AM +0300, Dmitry Osipenko wrote:
> Commit 33a8eb8 ("Implement runtime PM") introduced HW reset control. It
> causes a hang on Tegra20 if both display controllers are utilized (RGB
> panel and HDMI). The TRM suggests that each display controller has its own
> reset control, apparently it is not correct. Let's remove the interaction
> with the resets for now as a workaround.
> 
> Fixes: 33a8eb8d40ee ("drm/tegra: dc: Implement runtime PM")
> Signed-off-by: Dmitry Osipenko <digetx at gmail.com>
> ---
>  drivers/gpu/drm/tegra/dc.c | 15 ---------------
>  1 file changed, 15 deletions(-)

Do you mind if I parameterize this to restrict omission of the assert
and deassert to Tegra20? I'm fairly sure that these resets are important
on later chips in order to properly reset the display controllers.

My proposal would be to add a field to struct tegra_dc_soc_info (maybe
.broken_reset) that will be set only on Tegra20 to still allow the DC to
be reset on later generations.

Thierry
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