drm/nv50: respect LVDS link count from EDID on SPWG panels

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 15 insertions, 3 deletions

diff --git a/drivers/gpu/drm/nouveau/nv50_display.c b/drivers/gpu/drm/nouveau/nv50_display.c
index 75a376cc342a..74a3f6872701 100644
--- a/drivers/gpu/drm/nouveau/nv50_display.c
+++ b/drivers/gpu/drm/nouveau/nv50_display.c
@@ -517,13 +517,25 @@ nv50_display_script_select(struct drm_device *dev, struct dcb_entry *dcb,
                         if (bios->fp.if_is_24bit)
                                 script |= 0x0200;
                 } else {
+                        /* determine number of lvds links */
+                        if (nv_connector && nv_connector->edid &&
+                            nv_connector->dcb->type == DCB_CONNECTOR_LVDS_SPWG) {
+                                /* http://www.spwg.org */
+                                if (((u8 *)nv_connector->edid)[121] == 2)
+                                        script |= 0x0100;
+                        } else
                         if (pxclk >= bios->fp.duallink_transition_clk) {
                                 script |= 0x0100;
+                        }
+
+                        /* determine panel depth */
+                        if (script & 0x0100) {
                                 if (bios->fp.strapless_is_24bit & 2)
                                         script |= 0x0200;
-                        } else
-                        if (bios->fp.strapless_is_24bit & 1)
-                                script |= 0x0200;
+                        } else {
+                                if (bios->fp.strapless_is_24bit & 1)
+                                        script |= 0x0200;
+                        }
 
                         if (nv_connector && nv_connector->edid &&
                             (nv_connector->edid->revision >= 4) &&