Commits
Paul Kocialkowski committed 7cf4466df6c
drm/sun4i: tcon: Prepare and enable TCON channel 0 clock at init [ Upstream commit b14e945bda8ae227d1bf2b1837c0c4a61721cd1a ] When initializing clocks, a reference to the TCON channel 0 clock is obtained. However, the clock is never prepared and enabled later. Switching from simplefb to DRM actually disables the clock (that was usually configured by U-Boot) because of that. On the V3s, this results in a hang when writing to some mixer registers when switching over to DRM from simplefb. Fix this by preparing and enabling the clock when initializing other clocks. Waiting for sun4i_tcon_channel_enable to enable the clock is apparently too late and results in the same mixer register access hang. Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com> Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190131132550.26355-1-paul.kocialkowski@bootlin.com Signed-off-by: Sasha Levin <sashal@kernel.org>