diff options
author | Ville Syrjälä <ville.syrjala@linux.intel.com> | 2017-11-08 18:25:04 +0300 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-12-05 13:26:37 +0300 |
commit | d8f74d70634aa0dfe063d0e445f683b0545fa5b8 (patch) | |
tree | 5ce68172165049666a5b67997a7329bfeaf6a90b /include/drm | |
parent | e685410c5f30a19c54d652e033942ed270d31b61 (diff) | |
download | linux-d8f74d70634aa0dfe063d0e445f683b0545fa5b8.tar.xz |
drm/edid: Don't send non-zero YQ in AVI infoframe for HDMI 1.x sinks
commit 9271c0ca573e02a360b636ecd8cb408852f4e9f6 upstream.
Apparently some sinks look at the YQ bits even when receiving RGB,
and they get somehow confused when they see a non-zero YQ value.
So we can't just blindly follow CEA-861-F and set YQ to match the
RGB range.
Unfortunately there is no good way to tell whether the sink
designer claims to have read CEA-861-F. The CEA extension block
revision number has generally been stuck at 3 since forever,
and even a very recently manufactured sink might be based on
an old design so the manufacturing date doesn't seem like
something we can use. In lieu of better information let's
follow CEA-861-F only for HDMI 2.0 sinks, since HDMI 2.0 is
based on CEA-861-F. For HDMI 1.x sinks we'll always set YQ=0.
The alternative would of course be to always set YQ=0. And if
we ever encounter a HDMI 2.0+ sink with this bug that's what
we'll probably have to do.
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Neil Kownacki <njkkow@gmail.com>
Reported-by: Neil Kownacki <njkkow@gmail.com>
Tested-by: Neil Kownacki <njkkow@gmail.com>
Fixes: fcc8a22cc905 ("drm/edid: Set YQ bits in the AVI infoframe according to CEA-861-F")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101639
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171108152504.12596-1-ville.syrjala@linux.intel.com
Acked-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/drm')
-rw-r--r-- | include/drm/drm_edid.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h index 1e1908a6b1d6..a992434ded99 100644 --- a/include/drm/drm_edid.h +++ b/include/drm/drm_edid.h @@ -360,7 +360,8 @@ void drm_hdmi_avi_infoframe_quant_range(struct hdmi_avi_infoframe *frame, const struct drm_display_mode *mode, enum hdmi_quantization_range rgb_quant_range, - bool rgb_quant_range_selectable); + bool rgb_quant_range_selectable, + bool is_hdmi2_sink); /** * drm_eld_mnl - Get ELD monitor name length in bytes. |