From e1ba914ffad4be694c78f7dad791963ffa42857b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Sat, 2 Mar 2019 14:37:33 +0200 Subject: [PATCH 2/2] drm/i915: Pick the first mode from EDID as the fixed mode when there is no preferred mode MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Some monitors apparently forget to mark any mode as preferred in the EDID. In this particular case we have a very generic looking ID "PNP Model 0 Serial Number 4" / "LVDS 800x600" so a specific quirk doesn't seem particularly wise. Also the quirk we have (EDID_QUIRK_FIRST_DETAILED_PREFERRED) is actually defunct so we'd have to fix it first. When there is no preferred mode we currently fall back to the VBT. That approach fails us here as the VBT mode is 1024x768 whereas the panel resolution is 800x600. So instead of falling back to the VBT when there is no preferred mode let's just pick the first probed mode. Only if the EDID provided no modes we fall back to the VBT. For this machine the VBIOS would appear to select the 800x600 60Hz EST mode rather than the first detailed mode (which is the new fallback will pick). The two modes differ only by having opposite sync polarities, which does not seem to matter to the panel in question. Cc: Adam Jackson Cc: Roberto Viola Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109780 Signed-off-by: Ville Syrjälä --- drivers/gpu/drm/i915/intel_panel.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c index 90d9ac8a8cec..e370ec5683c8 100644 --- a/drivers/gpu/drm/i915/intel_panel.c +++ b/drivers/gpu/drm/i915/intel_panel.c @@ -104,11 +104,10 @@ intel_panel_edid_fixed_mode(struct intel_connector *connector) { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); const struct drm_display_mode *scan; + struct drm_display_mode *fixed_mode; /* prefer fixed mode from EDID if available */ list_for_each_entry(scan, &connector->base.probed_modes, head) { - struct drm_display_mode *fixed_mode; - if ((scan->type & DRM_MODE_TYPE_PREFERRED) == 0) continue; @@ -123,7 +122,22 @@ intel_panel_edid_fixed_mode(struct intel_connector *connector) return fixed_mode; } - return NULL; + scan = list_first_entry(&connector->base.probed_modes, + typeof(*scan), head); + if (!scan) + return NULL; + + fixed_mode = drm_mode_duplicate(&dev_priv->drm, scan); + if (!fixed_mode) + return NULL; + + fixed_mode->type |= DRM_MODE_TYPE_PREFERRED; + + DRM_DEBUG_KMS("[CONNECTOR:%d:%s] using first mode from EDID: ", + connector->base.base.id, connector->base.name); + drm_mode_debug_printmodeline(fixed_mode); + + return fixed_mode; } /* adjusted_mode has been preset to be the panel's fixed mode */ -- 2.19.2