drm/i915: move is_dual_link_lvds to intel_lvds.c

Just a prep patch to make this a property of intel_lvds. Makes more
sense, removes clutter from intel_display.c and eventually I want to
move all the encoder special cases wrt clock handling to encoders
anyway.

v2: Add an intel_ prefixe to is_dual_link_lvds since it's non-static
now.

Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index be19b6d..2705da3 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -472,61 +472,14 @@
 	POSTING_READ(DPIO_CTL);
 }
 
-static int intel_dual_link_lvds_callback(const struct dmi_system_id *id)
-{
-	DRM_INFO("Forcing lvds to dual link mode on %s\n", id->ident);
-	return 1;
-}
-
-static const struct dmi_system_id intel_dual_link_lvds[] = {
-	{
-		.callback = intel_dual_link_lvds_callback,
-		.ident = "Apple MacBook Pro (Core i5/i7 Series)",
-		.matches = {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro8,2"),
-		},
-	},
-	{ }	/* terminating entry */
-};
-
-static bool is_dual_link_lvds(struct drm_i915_private *dev_priv,
-			      unsigned int reg)
-{
-	unsigned int val;
-
-	/* use the module option value if specified */
-	if (i915_lvds_channel_mode > 0)
-		return i915_lvds_channel_mode == 2;
-
-	if (dmi_check_system(intel_dual_link_lvds))
-		return true;
-
-	if (dev_priv->lvds_val)
-		val = dev_priv->lvds_val;
-	else {
-		/* BIOS should set the proper LVDS register value at boot, but
-		 * in reality, it doesn't set the value when the lid is closed;
-		 * we need to check "the value to be set" in VBT when LVDS
-		 * register is uninitialized.
-		 */
-		val = I915_READ(reg);
-		if (!(val & ~(LVDS_PIPE_MASK | LVDS_DETECTED)))
-			val = dev_priv->bios_lvds_val;
-		dev_priv->lvds_val = val;
-	}
-	return (val & LVDS_CLKB_POWER_MASK) == LVDS_CLKB_POWER_UP;
-}
-
 static const intel_limit_t *intel_ironlake_limit(struct drm_crtc *crtc,
 						int refclk)
 {
 	struct drm_device *dev = crtc->dev;
-	struct drm_i915_private *dev_priv = dev->dev_private;
 	const intel_limit_t *limit;
 
 	if (intel_pipe_has_type(crtc, INTEL_OUTPUT_LVDS)) {
-		if (is_dual_link_lvds(dev_priv, PCH_LVDS)) {
+		if (intel_is_dual_link_lvds(dev)) {
 			/* LVDS dual channel */
 			if (refclk == 100000)
 				limit = &intel_limits_ironlake_dual_lvds_100m;
@@ -550,11 +503,10 @@
 static const intel_limit_t *intel_g4x_limit(struct drm_crtc *crtc)
 {
 	struct drm_device *dev = crtc->dev;
-	struct drm_i915_private *dev_priv = dev->dev_private;
 	const intel_limit_t *limit;
 
 	if (intel_pipe_has_type(crtc, INTEL_OUTPUT_LVDS)) {
-		if (is_dual_link_lvds(dev_priv, LVDS))
+		if (intel_is_dual_link_lvds(dev))
 			/* LVDS with dual channel */
 			limit = &intel_limits_g4x_dual_channel_lvds;
 		else
@@ -686,7 +638,6 @@
 
 {
 	struct drm_device *dev = crtc->dev;
-	struct drm_i915_private *dev_priv = dev->dev_private;
 	intel_clock_t clock;
 	int err = target;
 
@@ -696,7 +647,7 @@
 		 * We haven't figured out how to reliably set up different
 		 * single/dual channel state, if we even can.
 		 */
-		if (is_dual_link_lvds(dev_priv, LVDS))
+		if (intel_is_dual_link_lvds(dev))
 			clock.p2 = limit->p2.p2_fast;
 		else
 			clock.p2 = limit->p2.p2_slow;
@@ -749,7 +700,6 @@
 			intel_clock_t *best_clock)
 {
 	struct drm_device *dev = crtc->dev;
-	struct drm_i915_private *dev_priv = dev->dev_private;
 	intel_clock_t clock;
 	int max_n;
 	bool found;
@@ -764,7 +714,7 @@
 			lvds_reg = PCH_LVDS;
 		else
 			lvds_reg = LVDS;
-		if (is_dual_link_lvds(dev_priv, lvds_reg))
+		if (intel_is_dual_link_lvds(dev))
 			clock.p2 = limit->p2.p2_fast;
 		else
 			clock.p2 = limit->p2.p2_slow;
@@ -5356,7 +5306,7 @@
 	if (is_lvds) {
 		if ((intel_panel_use_ssc(dev_priv) &&
 		     dev_priv->lvds_ssc_freq == 100) ||
-		    is_dual_link_lvds(dev_priv, PCH_LVDS))
+		    intel_is_dual_link_lvds(dev))
 			factor = 25;
 	} else if (is_sdvo && is_tv)
 		factor = 20;
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index a74c572..7ca7772 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -441,6 +441,7 @@
 extern void intel_mark_fb_busy(struct drm_i915_gem_object *obj);
 extern void intel_mark_fb_idle(struct drm_i915_gem_object *obj);
 extern bool intel_lvds_init(struct drm_device *dev);
+extern bool intel_is_dual_link_lvds(struct drm_device *dev);
 extern void intel_dp_init(struct drm_device *dev, int output_reg,
 			  enum port port);
 extern void intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index b9a660a..4158a88 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -903,6 +903,59 @@
 	return false;
 }
 
+static int intel_dual_link_lvds_callback(const struct dmi_system_id *id)
+{
+	DRM_INFO("Forcing lvds to dual link mode on %s\n", id->ident);
+	return 1;
+}
+
+static const struct dmi_system_id intel_dual_link_lvds[] = {
+	{
+		.callback = intel_dual_link_lvds_callback,
+		.ident = "Apple MacBook Pro (Core i5/i7 Series)",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro8,2"),
+		},
+	},
+	{ }	/* terminating entry */
+};
+
+bool intel_is_dual_link_lvds(struct drm_device *dev)
+{
+	unsigned int val;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	u32 lvds_reg;
+
+	if (HAS_PCH_SPLIT(dev)) {
+		lvds_reg = PCH_LVDS;
+	} else {
+		lvds_reg = LVDS;
+	}
+
+	/* use the module option value if specified */
+	if (i915_lvds_channel_mode > 0)
+		return i915_lvds_channel_mode == 2;
+
+	if (dmi_check_system(intel_dual_link_lvds))
+		return true;
+
+	if (dev_priv->lvds_val)
+		val = dev_priv->lvds_val;
+	else {
+		/* BIOS should set the proper LVDS register value at boot, but
+		 * in reality, it doesn't set the value when the lid is closed;
+		 * we need to check "the value to be set" in VBT when LVDS
+		 * register is uninitialized.
+		 */
+		val = I915_READ(lvds_reg);
+		if (!(val & ~(LVDS_PIPE_MASK | LVDS_DETECTED)))
+			val = dev_priv->bios_lvds_val;
+		dev_priv->lvds_val = val;
+	}
+	return (val & LVDS_CLKB_POWER_MASK) == LVDS_CLKB_POWER_UP;
+}
+
 static bool intel_lvds_supported(struct drm_device *dev)
 {
 	/* With the introduction of the PCH we gained a dedicated