From 196e077dc165a307efbd9e7569f81bbdbcf18f65 Mon Sep 17 00:00:00 2001 From: Paulo Zanoni Date: Fri, 15 Feb 2013 13:36:27 -0200 Subject: [PATCH] drm: don't add inferred modes for monitors that don't support them If bit 0 of the features byte (0x18) is set to 0, then, according to the EDID spec, "the display is non-continuous frequency (multi-mode) and is only specified to accept the video timing formats that are listed in Base EDID and certain Extension Blocks". For more information, please see the EDID spec, check the notes of the table that explains the "Feature Support" byte (18h) and also the notes on the tables of the section that explains "Display Range Limits & Additional Timing Description Definition (tag #FDh)". Cc: stable@vger.kernel.org Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45729 Reviewed-by: Alex Deucher Reviewed-by: Adam Jackson Signed-off-by: Paulo Zanoni Signed-off-by: Dave Airlie --- drivers/gpu/drm/drm_edid.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index e1aca7b53987..67aa0dd68250 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -2054,7 +2054,8 @@ int drm_add_edid_modes(struct drm_connector *connector, struct edid *edid) num_modes += add_cvt_modes(connector, edid); num_modes += add_standard_modes(connector, edid); num_modes += add_established_modes(connector, edid); - num_modes += add_inferred_modes(connector, edid); + if (edid->features & DRM_EDID_FEATURE_DEFAULT_GTF) + num_modes += add_inferred_modes(connector, edid); num_modes += add_cea_modes(connector, edid); if (quirks & (EDID_QUIRK_PREFER_LARGE_60 | EDID_QUIRK_PREFER_LARGE_75)) -- 2.20.1