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author | Ville Syrjälä <ville.syrjala@linux.intel.com> | 2015-10-08 11:43:32 +0300 |
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committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2015-10-20 12:01:28 +0200 |
commit | fa3a7340eaa174a36c12c31747dc6eccd08530b5 (patch) | |
tree | dd7f5b7239b9fd7adad05a61466b2902bbbee0f7 /drivers/gpu/drm/drm_edid.c | |
parent | affa0e033b04996700434312c76df3c78f683870 (diff) | |
download | linux-stable-fa3a7340eaa174a36c12c31747dc6eccd08530b5.tar.gz linux-stable-fa3a7340eaa174a36c12c31747dc6eccd08530b5.tar.bz2 linux-stable-fa3a7340eaa174a36c12c31747dc6eccd08530b5.zip |
drm/edid: Fix up clock for CEA/HDMI modes specified via detailed timings
EDID detailed timings have a resolution of 10kHz for the pixel clock, so
they can't represent certain CEA/HDMI modes accurately. If we see a mode
coming in via detailed timings which otherwise matches one of the
CEA/HDMI modes except the clock is just a bit off, let's assume that the
intention was for that mode to be one of the CEA/HDMI modes and go ahead
and fix up the clock to match the CEA/HDMI spec exactly (well, as close
as we can get with the 1 kHz resolution we use).
This should help code that's looking for an exact clock match (eg. i915
audio N/CTS setup).
Cc: Adam Jackson <ajax@redhat.com>
Cc: Clint Taylor <clinton.a.taylor@intel.com>
Cc: Libin Yang <libin.yang@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu/drm/drm_edid.c')
-rw-r--r-- | drivers/gpu/drm/drm_edid.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index d895556be4f0..977915cf530a 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -2418,6 +2418,8 @@ add_cvt_modes(struct drm_connector *connector, struct edid *edid) return closure.modes; } +static void fixup_detailed_cea_mode_clock(struct drm_display_mode *mode); + static void do_detailed_mode(struct detailed_timing *timing, void *c) { @@ -2434,6 +2436,13 @@ do_detailed_mode(struct detailed_timing *timing, void *c) if (closure->preferred) newmode->type |= DRM_MODE_TYPE_PREFERRED; + /* + * Detailed modes are limited to 10kHz pixel clock resolution, + * so fix up anything that looks like CEA/HDMI mode, but the clock + * is just slightly off. + */ + fixup_detailed_cea_mode_clock(newmode); + drm_mode_probed_add(closure->connector, newmode); closure->modes++; closure->preferred = 0; @@ -3103,6 +3112,45 @@ add_cea_modes(struct drm_connector *connector, struct edid *edid) return modes; } +static void fixup_detailed_cea_mode_clock(struct drm_display_mode *mode) +{ + const struct drm_display_mode *cea_mode; + int clock1, clock2, clock; + u8 mode_idx; + const char *type; + + mode_idx = drm_match_cea_mode(mode) - 1; + if (mode_idx < ARRAY_SIZE(edid_cea_modes)) { + type = "CEA"; + cea_mode = &edid_cea_modes[mode_idx]; + clock1 = cea_mode->clock; + clock2 = cea_mode_alternate_clock(cea_mode); + } else { + mode_idx = drm_match_hdmi_mode(mode) - 1; + if (mode_idx < ARRAY_SIZE(edid_4k_modes)) { + type = "HDMI"; + cea_mode = &edid_4k_modes[mode_idx]; + clock1 = cea_mode->clock; + clock2 = hdmi_mode_alternate_clock(cea_mode); + } else { + return; + } + } + + /* pick whichever is closest */ + if (abs(mode->clock - clock1) < abs(mode->clock - clock2)) + clock = clock1; + else + clock = clock2; + + if (mode->clock == clock) + return; + + DRM_DEBUG("detailed mode matches %s VIC %d, adjusting clock %d -> %d\n", + type, mode_idx + 1, mode->clock, clock); + mode->clock = clock; +} + static void parse_hdmi_vsdb(struct drm_connector *connector, const u8 *db) { |