Re: [RFC PATCH 3/5] drm/i915: register LVDS connector even if we can't get a panel mode

[Seth Forshee <seth.forshee@canonical.com>]

On Fri, Aug 03, 2012 at 05:27:02PM +0100, Matthew Garrett wrote:
> On Fri, Aug 03, 2012 at 11:24:51AM -0500, Seth Forshee wrote:
> 
> > This is one of the things I wasn't so sure about. There are various
> > checks in intel_lvds_init() that can cause it to bail out before we try
> > to get the EDID, and I don't fully understand all of them. If non-laptop
> > machines are expected to bail out before the EDID check then the
> > approach I've taken seems reasonable. Otherwise adding a quirk probably
> > is a good idea.
> 
> I know we've previously had problems with machines with phantom LVDS 
> hardware, but I'm not sure what the current state of affairs is.

It turns out that the framebuffer console issue is due to not having a
mode when initializing LVDS. As a result 1024x768 is getting used for
the framebuffer.

So quirking is going to fix this situation. In fact, with the changes
below switcheroo seems to work perfectly, without any of these patches
at all.


diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 627fe35..d83e5bc 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -503,6 +503,7 @@ typedef struct drm_i915_private {
 	enum intel_pch pch_type;
 
 	unsigned long quirks;
+	struct drm_display_mode *lvds_quirk_mode;
 
 	/* Register state */
 	bool modeset_on_lid;
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index f615976..c810177 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -7069,7 +7069,7 @@ static void intel_init_display(struct drm_device *dev)
  * resume, or other times.  This quirk makes sure that's the case for
  * affected systems.
  */
-static void quirk_pipea_force(struct drm_device *dev)
+static void quirk_pipea_force(struct drm_device *dev, void *data)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 
@@ -7080,7 +7080,7 @@ static void quirk_pipea_force(struct drm_device *dev)
 /*
  * Some machines (Lenovo U160) do not work with SSC on LVDS for some reason
  */
-static void quirk_ssc_force_disable(struct drm_device *dev)
+static void quirk_ssc_force_disable(struct drm_device *dev, void *data)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	dev_priv->quirks |= QUIRK_LVDS_SSC_DISABLE;
@@ -7091,48 +7091,74 @@ static void quirk_ssc_force_disable(struct drm_device *dev)
  * A machine (e.g. Acer Aspire 5734Z) may need to invert the panel backlight
  * brightness value
  */
-static void quirk_invert_brightness(struct drm_device *dev)
+static void quirk_invert_brightness(struct drm_device *dev, void *data)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	dev_priv->quirks |= QUIRK_INVERT_BRIGHTNESS;
 	DRM_INFO("applying inverted panel brightness quirk\n");
 }
 
+/*
+ * Some machines (e.g. certain Macbooks) may not be able to determine the
+ * LVDS mode during driver initialization
+ */
+static void quirk_lvds_panel_mode(struct drm_device *dev, void *data)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	dev_priv->lvds_quirk_mode = data;
+	DRM_INFO("applying LVDS panel mode quirk: %p\n", data);
+}
+
+/* LVDS panel mode for Macbook Pro 8,2 */
+struct drm_display_mode mbp82_panel_mode = {
+	DRM_MODE("1440x900", DRM_MODE_TYPE_DRIVER, 88750, 1440, 1488, 1520,
+		 1600, 0, 900, 903, 909, 926, 0,
+		 DRM_MODE_FLAG_NVSYNC | DRM_MODE_FLAG_NHSYNC)
+};
+
 struct intel_quirk {
 	int device;
 	int subsystem_vendor;
 	int subsystem_device;
-	void (*hook)(struct drm_device *dev);
+	void (*hook)(struct drm_device *dev, void *data);
+	void *hook_data;
 };
 
 static struct intel_quirk intel_quirks[] = {
 	/* HP Mini needs pipe A force quirk (LP: #322104) */
-	{ 0x27ae, 0x103c, 0x361a, quirk_pipea_force },
+	{ 0x27ae, 0x103c, 0x361a, quirk_pipea_force, NULL },
 
 	/* Thinkpad R31 needs pipe A force quirk */
-	{ 0x3577, 0x1014, 0x0505, quirk_pipea_force },
+	{ 0x3577, 0x1014, 0x0505, quirk_pipea_force, NULL },
 	/* Toshiba Protege R-205, S-209 needs pipe A force quirk */
-	{ 0x2592, 0x1179, 0x0001, quirk_pipea_force },
+	{ 0x2592, 0x1179, 0x0001, quirk_pipea_force, NULL },
 
 	/* ThinkPad X30 needs pipe A force quirk (LP: #304614) */
-	{ 0x3577,  0x1014, 0x0513, quirk_pipea_force },
+	{ 0x3577,  0x1014, 0x0513, quirk_pipea_force, NULL },
 	/* ThinkPad X40 needs pipe A force quirk */
 
 	/* ThinkPad T60 needs pipe A force quirk (bug #16494) */
-	{ 0x2782, 0x17aa, 0x201a, quirk_pipea_force },
+	{ 0x2782, 0x17aa, 0x201a, quirk_pipea_force, NULL },
 
 	/* 855 & before need to leave pipe A & dpll A up */
-	{ 0x3582, PCI_ANY_ID, PCI_ANY_ID, quirk_pipea_force },
-	{ 0x2562, PCI_ANY_ID, PCI_ANY_ID, quirk_pipea_force },
+	{ 0x3582, PCI_ANY_ID, PCI_ANY_ID, quirk_pipea_force, NULL },
+	{ 0x2562, PCI_ANY_ID, PCI_ANY_ID, quirk_pipea_force, NULL },
 
 	/* Lenovo U160 cannot use SSC on LVDS */
-	{ 0x0046, 0x17aa, 0x3920, quirk_ssc_force_disable },
+	{ 0x0046, 0x17aa, 0x3920, quirk_ssc_force_disable, NULL },
 
 	/* Sony Vaio Y cannot use SSC on LVDS */
-	{ 0x0046, 0x104d, 0x9076, quirk_ssc_force_disable },
+	{ 0x0046, 0x104d, 0x9076, quirk_ssc_force_disable, NULL },
 
 	/* Acer Aspire 5734Z must invert backlight brightness */
-	{ 0x2a42, 0x1025, 0x0459, quirk_invert_brightness },
+	{ 0x2a42, 0x1025, 0x0459, quirk_invert_brightness, NULL },
+
+	/*
+	 * Some versions of the Macbook Pro 8,2 cannot use SSC and
+	 * cannot get the panel mode on LVDS
+	 */
+	{ 0x0116, 0x106b, 0x00dc, quirk_ssc_force_disable, NULL },
+	{ 0x0116, 0x106b, 0x00dc, quirk_lvds_panel_mode, &mbp82_panel_mode },
 };
 
 static void intel_init_quirks(struct drm_device *dev)
@@ -7148,7 +7174,7 @@ static void intel_init_quirks(struct drm_device *dev)
 		     q->subsystem_vendor == PCI_ANY_ID) &&
 		    (d->subsystem_device == q->subsystem_device ||
 		     q->subsystem_device == PCI_ANY_ID))
-			q->hook(dev);
+			q->hook(dev, q->hook_data);
 	}
 }
 
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index e05c0d3..303068d 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -996,6 +996,7 @@ bool intel_lvds_init(struct drm_device *dev)
 	 * 1) check for EDID on DDC
 	 * 2) check for VBT data
 	 * 3) check to see if LVDS is already on
+	 * 4) check for LVDS panel mode quirk
 	 *    if none of the above, no panel
 	 * 4) make sure lid is open
 	 *    if closed, act like it's not there for now
@@ -1058,15 +1059,25 @@ bool intel_lvds_init(struct drm_device *dev)
 	 */
 
 	/* Ironlake: FIXME if still fail, not try pipe mode now */
-	if (HAS_PCH_SPLIT(dev))
-		goto failed;
-
-	lvds = I915_READ(LVDS);
-	pipe = (lvds & LVDS_PIPEB_SELECT) ? 1 : 0;
-	crtc = intel_get_crtc_for_pipe(dev, pipe);
+	if (!HAS_PCH_SPLIT(dev)) {
+		lvds = I915_READ(LVDS);
+		pipe = (lvds & LVDS_PIPEB_SELECT) ? 1 : 0;
+		crtc = intel_get_crtc_for_pipe(dev, pipe);
+
+		if (crtc && (lvds & LVDS_PORT_EN)) {
+			intel_lvds->fixed_mode = intel_crtc_mode_get(dev, crtc);
+			if (intel_lvds->fixed_mode) {
+				intel_lvds->fixed_mode->type |=
+					DRM_MODE_TYPE_PREFERRED;
+				goto out;
+			}
+		}
+	}
 
-	if (crtc && (lvds & LVDS_PORT_EN)) {
-		intel_lvds->fixed_mode = intel_crtc_mode_get(dev, crtc);
+	/* Check for panel mode quirk as a last resort */
+	if (dev_priv->lvds_quirk_mode) {
+		intel_lvds->fixed_mode =
+			drm_mode_duplicate(dev, dev_priv->lvds_quirk_mode);
 		if (intel_lvds->fixed_mode) {
 			intel_lvds->fixed_mode->type |=
 				DRM_MODE_TYPE_PREFERRED;