[Intel-gfx] [PATCH] drm/i915: Fix sync to vblank when VGA output is turned off

[Jesse Barnes]

On Mon, 09 Nov 2009 12:51:22 +0800
Li Peng <peng.li at linux.intel.com> wrote:

> In current vblank-wait implementation, if we turn off VGA output,
> drm_wait_vblank will still wait on the disabled pipe until timeout,
> because vblank on the pipe is assumed be enabled. This would cause
> slow system response on some system such as moblin.
> 
> This patch resolve the issue by adding a drm helper function
> drm_vblank_off which explicitly clear vblank_enabled[crtc], wake up
> any waiting queue and save last vblank counter before turning off
> crtc. It also slightly change drm_vblank_get to ensure that we will
> will return immediately if trying to wait on a disabled pipe.
> 
> Signed-off-by: Li Peng <peng.li at intel.com>

Looks like a good patch, thanks for fixing this up.

Reviewed-by: Jesse Barnes <jbarnes at virtuousgeek.org>

Thanks,
Jesse