Re: [PATCH] drm/i915: eDP aux needs vdd

[Chris Wilson <chris@chris-wilson.co.uk>]

On Tue, 12 Jun 2012 13:11:41 +0200, Daniel Vetter <daniel.vetter@ffwll.ch> wrote:
> The new oui probe has been missing these.
> 
> This issue has been introduce in
> 
> commit 0d198328538276c4459ef5de081e68ae60e6c4c2
> Author: Adam Jackson <ajax@redhat.com>
> Date:   Mon May 14 16:05:47 2012 -0400
> 
>     drm/i915/dp: Probe branch/sink OUIs
> 
> v2: Do the eDP vdd dance of simply not probing the OUI on eDP panels
> as suggested by Chris Wilson.
> 
> Cc: Adam Jackson <ajax@redhat.com>
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=50808
> Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
> Bugreport: http://permalink.gmane.org/gmane.comp.video.dri.devel/69695
> Tested-by: Yang Guang <guang.a.yang@intel.com>
> Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> ---
>  drivers/gpu/drm/i915/intel_dp.c |    4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 296cfc2..fbc30a5 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -1970,6 +1970,8 @@ intel_dp_probe_oui(struct intel_dp *intel_dp)
>  {
>  	u8 buf[3];
>  
> +	ironlake_edp_panel_vdd_on(intel_dp);
> +
>  	if (!(intel_dp->dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
>  		return;

The side effect is that we then need to introduce a layer of onion here.
>  
> @@ -1980,6 +1982,8 @@ intel_dp_probe_oui(struct intel_dp *intel_dp)
>  	if (intel_dp_aux_native_read_retry(intel_dp, DP_BRANCH_OUI, buf, 3))
>  		DRM_DEBUG_KMS("Branch OUI: %02hx%02hx%02hx\n",
>  			      buf[0], buf[1], buf[2]);
> +
> +	ironlake_edp_panel_vdd_off(intel_dp, false);
>  }

-- 
Chris Wilson, Intel Open Source Technology Centre