Re: -next queue and EDID stuff

[Ian Pilcher <arequipeno@gmail.com>]

On 08/29/2012 02:56 AM, Daniel Vetter wrote:
> Wrt intel infoframes issues: Have you retested on latest 3.6-rc kernels?
> We've fixed quite a few bugs for our infoframe support recently ...

Tested just now.  The behavior has changed.  I now need to use *both*
flags to make my display work with an Intel GPU.  (Previously, the
NO_AUDIO flag was sufficient to make the display work with Intel
graphics.)  Presumably, the Intel driver is now sending AVI InfoFrames.

Thinking a bit more about this, I'm starting to rethink my assertion
that the Intel driver is at fault here.  On one hand, it doesn't make
any sense to send audio InfoFrames to a non-HDMI display.  (BTW, I'm
assuming that a display with a DisplayPort port will show up as HDMI.)

On the other hand, it can be argued that the DRM layer is giving
conflicting information to the driver -- drm_detect_hdmi_monitor is
returning FALSE, but drm_detect_monitor_audio is returning TRUE.  AFAIK,
this doesn't make any sense either.

This leads me to propose that drm_detect_monitor_audio return FALSE if
either EDID_QUIRK_DISABLE_INFOFRAMES or EDID_QUIRK_NO_AUDIO is set.

bool drm_detect_monitor_audio(struct edid *edid)
{
         u8 *edid_ext;
         int i, j;
         bool has_audio = false;
         int start_offset, end_offset;
         char buf[EDID_DISPLAY_ID_BUF_SIZE];

         if (edid_get_quirks(edid) & (EDID_QUIRK_NO_AUDIO |
                                      EDID_QUIRK_DISABLE_INFOFRAMES)) {
                 DRM_INFO("Disabling HDMI audio on display %s "
                          "due to EDID quirk\n",
                          drm_edid_display_id_format(edid->display_id,
                                                     buf, 1));
                 goto end;
         }

         ...

EDID_QUIRK_DISABLE_INFOFRAMES would then be sufficient to make the LG
L246WP work with both nVidia and Intel GPUs.  (ATI GPUs should work as
well; I just don't have any hardware to test.)

Ajax - Does this address your objections?  If so, I'll spin another
patch set.

Thanks!

-- 
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Ian Pilcher                                         arequipeno@gmail.com
"If you're going to shift my paradigm ... at least buy me dinner first."
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