Re: [PATCH 1/2] drm/rockchip: vop: clear DMA stop bit on flush on RK3066

From: Greg KH
Date: Sun May 19 2024 - 03:59:58 EST


On Sun, May 19, 2024 at 04:31:31AM -0300, Val Packett wrote:
> On the RK3066, there is a bit that must be cleared on flush, otherwise
> we do not get display output (at least for RGB).
>
> Signed-off-by: Val Packett <val@xxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
> Hi! This was required to get display working on an old RK3066 tablet,
> along with the next tiny patch in the series enabling the RGB output.
>
> I have spent quite a lot of time banging my head against the wall debugging
> that display (especially since at the same time a scaler chip is used for
> LVDS encoding), but finally adding debug prints showed that RK3066_SYS_CTRL0
> ended up being reset to all-zero after being written correctly upon init.
> Looking at the register definitions in the vendor driver revealed that the
> reason was pretty self-explanatory: "dma_stop".

What commit id does this fix?

thanks,

greg k-h