UPSTREAM: drm/edid: Make the detailed timing CEA/HDMI mode fixup accept up to 5kHz...

[firefly-linux-kernel-4.4.55.git] / drivers / gpu / drm / drm_edid.c

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 7e7e4446962bc80ced41bf8a1c5e5bd42aaa30e2..2d6932c9a351223b26aec2a0cc0edbb3dc2a7cfb 100644 (file)
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -2556,6 +2556,33 @@ cea_mode_alternate_clock(const struct drm_display_mode *cea_mode)
        return clock;
 }
 
+static u8 drm_match_cea_mode_clock_tolerance(const struct drm_display_mode *to_match,
+                                            unsigned int clock_tolerance)
+{
+       u8 mode;
+
+       if (!to_match->clock)
+               return 0;
+
+       for (mode = 0; mode < ARRAY_SIZE(edid_cea_modes); mode++) {
+               const struct drm_display_mode *cea_mode = &edid_cea_modes[mode];
+               unsigned int clock1, clock2;
+
+               /* Check both 60Hz and 59.94Hz */
+               clock1 = cea_mode->clock;
+               clock2 = cea_mode_alternate_clock(cea_mode);
+
+               if (abs(to_match->clock - clock1) > clock_tolerance &&
+                   abs(to_match->clock - clock2) > clock_tolerance)
+                       continue;
+
+               if (drm_mode_equal_no_clocks(to_match, cea_mode))
+                       return mode + 1;
+       }
+
+       return 0;
+}
+
 /**
  * drm_match_cea_mode - look for a CEA mode matching given mode
  * @to_match: display mode
@@ -2620,6 +2647,33 @@ hdmi_mode_alternate_clock(const struct drm_display_mode *hdmi_mode)
        return cea_mode_alternate_clock(hdmi_mode);
 }
 
+static u8 drm_match_hdmi_mode_clock_tolerance(const struct drm_display_mode *to_match,
+                                             unsigned int clock_tolerance)
+{
+       u8 mode;
+
+       if (!to_match->clock)
+               return 0;
+
+       for (mode = 0; mode < ARRAY_SIZE(edid_4k_modes); mode++) {
+               const struct drm_display_mode *hdmi_mode = &edid_4k_modes[mode];
+               unsigned int clock1, clock2;
+
+               /* Make sure to also match alternate clocks */
+               clock1 = hdmi_mode->clock;
+               clock2 = hdmi_mode_alternate_clock(hdmi_mode);
+
+               if (abs(to_match->clock - clock1) > clock_tolerance &&
+                   abs(to_match->clock - clock2) > clock_tolerance)
+                       continue;
+
+               if (drm_mode_equal_no_clocks(to_match, hdmi_mode))
+                       return mode + 1;
+       }
+
+       return 0;
+}
+
 /*
  * drm_match_hdmi_mode - look for a HDMI mode matching given mode
  * @to_match: display mode
@@ -3145,14 +3199,18 @@ static void fixup_detailed_cea_mode_clock(struct drm_display_mode *mode)
        u8 mode_idx;
        const char *type;
 
-       mode_idx = drm_match_cea_mode(mode) - 1;
+       /*
+        * allow 5kHz clock difference either way to account for
+        * the 10kHz clock resolution limit of detailed timings.
+        */
+       mode_idx = drm_match_cea_mode_clock_tolerance(mode, 5) - 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;
+               mode_idx = drm_match_hdmi_mode_clock_tolerance(mode, 5) - 1;
                if (mode_idx < ARRAY_SIZE(edid_4k_modes)) {
                        type = "HDMI";
                        cea_mode = &edid_4k_modes[mode_idx];