[Intel-gfx] [PATCH v3] drm/i915: Add missing MacBook Pro models with dual channel LVDS

[Lukas Wunner]

Single channel LVDS maxes out at 112 MHz. All 17" models with i915
graphics had a resolution of 1920x1200 (193 MHz), necessitating dual
channel LVDS. The 15" pre-retina models had either 1440x900 (106 MHz)
or 1680x1050 (119 MHz), both versions used dual channel LVDS even
though the smaller one would have fit into a single channel.

v2: Assume dual channel LVDS if the pixel clock necessitates it,
eliminating the need to hardcode 17" models, suggested by Jani Nikula.

v3: Fix typo, thanks Joonas Lahtinen.

Signed-off-by: Lukas Wunner <lukas at wunner.de>
Tested-by: Lukas Wunner <lukas at wunner.de>
Acked-by: Jani Nikula <jani.nikula at intel.com>
Cc: stable at vger.kernel.org
---
 drivers/gpu/drm/i915/intel_lvds.c | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index 071b96d..417ccab 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -812,12 +812,28 @@ static int intel_dual_link_lvds_callback(const struct dmi_system_id *id)
 static const struct dmi_system_id intel_dual_link_lvds[] = {
 	{
 		.callback = intel_dual_link_lvds_callback,
-		.ident = "Apple MacBook Pro (Core i5/i7 Series)",
+		.ident = "Apple MacBook Pro 15\" (2010)",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro6,2"),
+		},
+	},
+	{
+		.callback = intel_dual_link_lvds_callback,
+		.ident = "Apple MacBook Pro 15\" (2011)",
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro8,2"),
 		},
 	},
+	{
+		.callback = intel_dual_link_lvds_callback,
+		.ident = "Apple MacBook Pro 15\" (2012)",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro9,1"),
+		},
+	},
 	{ }	/* terminating entry */
 };
 
@@ -847,6 +863,11 @@ static bool compute_is_dual_link_lvds(struct intel_lvds_encoder *lvds_encoder)
 	if (i915.lvds_channel_mode > 0)
 		return i915.lvds_channel_mode == 2;
 
+	/* single channel LVDS is limited to 112 MHz */
+	if (lvds_encoder->attached_connector->base.panel.fixed_mode->clock
+	    > 112999)
+		return true;
+
 	if (dmi_check_system(intel_dual_link_lvds))
 		return true;
 
@@ -1104,6 +1125,8 @@ void intel_lvds_init(struct drm_device *dev)
 out:
 	mutex_unlock(&dev->mode_config.mutex);
 
+	intel_panel_init(&intel_connector->panel, fixed_mode, downclock_mode);
+
 	lvds_encoder->is_dual_link = compute_is_dual_link_lvds(lvds_encoder);
 	DRM_DEBUG_KMS("detected %s-link lvds configuration\n",
 		      lvds_encoder->is_dual_link ? "dual" : "single");
@@ -1118,7 +1141,6 @@ out:
 	}
 	drm_connector_register(connector);
 
-	intel_panel_init(&intel_connector->panel, fixed_mode, downclock_mode);
 	intel_panel_setup_backlight(connector, INVALID_PIPE);
 
 	return;
-- 
1.8.5.2 (Apple Git-48)