drm/i915: Convert DIP port switch cases to a simple macro

We have a couple of switch cases to compute the port value for the
VIDEO_DIP_CTL register. Replace them with a simple macro.

We do lose a few BUG() calls, but many people may consider that
an improvement.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_reg.h

@@ -2347,9 +2347,7 @@
 #define VIDEO_DIP_CTL		0x61170
 /* Pre HSW: */
 #define   VIDEO_DIP_ENABLE		(1 << 31)
-#define   VIDEO_DIP_PORT_B		(1 << 29)
-#define   VIDEO_DIP_PORT_C		(2 << 29)
-#define   VIDEO_DIP_PORT_D		(3 << 29)
+#define   VIDEO_DIP_PORT(port)		((port) << 29)
 #define   VIDEO_DIP_PORT_MASK		(3 << 29)
 #define   VIDEO_DIP_ENABLE_GCP		(1 << 25)
 #define   VIDEO_DIP_ENABLE_AVI		(1 << 21)

drivers/gpu/drm/i915/intel_hdmi.c

@@ -425,7 +425,7 @@ static void g4x_set_infoframes(struct drm_encoder *encoder,
 	struct intel_hdmi *intel_hdmi = &intel_dig_port->hdmi;
 	u32 reg = VIDEO_DIP_CTL;
 	u32 val = I915_READ(reg);
-	u32 port;
+	u32 port = VIDEO_DIP_PORT(intel_dig_port->port);
 
 	assert_hdmi_port_disabled(intel_hdmi);
 
@@ -449,18 +449,6 @@ static void g4x_set_infoframes(struct drm_encoder *encoder,
 		return;
 	}
 
-	switch (intel_dig_port->port) {
-	case PORT_B:
-		port = VIDEO_DIP_PORT_B;
-		break;
-	case PORT_C:
-		port = VIDEO_DIP_PORT_C;
-		break;
-	default:
-		BUG();
-		return;
-	}
-
 	if (port != (val & VIDEO_DIP_PORT_MASK)) {
 		if (val & VIDEO_DIP_ENABLE) {
 			val &= ~VIDEO_DIP_ENABLE;
@@ -491,7 +479,7 @@ static void ibx_set_infoframes(struct drm_encoder *encoder,
 	struct intel_hdmi *intel_hdmi = &intel_dig_port->hdmi;
 	u32 reg = TVIDEO_DIP_CTL(intel_crtc->pipe);
 	u32 val = I915_READ(reg);
-	u32 port;
+	u32 port = VIDEO_DIP_PORT(intel_dig_port->port);
 
 	assert_hdmi_port_disabled(intel_hdmi);
 
@@ -507,21 +495,6 @@ static void ibx_set_infoframes(struct drm_encoder *encoder,
 		return;
 	}
 
-	switch (intel_dig_port->port) {
-	case PORT_B:
-		port = VIDEO_DIP_PORT_B;
-		break;
-	case PORT_C:
-		port = VIDEO_DIP_PORT_C;
-		break;
-	case PORT_D:
-		port = VIDEO_DIP_PORT_D;
-		break;
-	default:
-		BUG();
-		return;
-	}
-
 	if (port != (val & VIDEO_DIP_PORT_MASK)) {
 		if (val & VIDEO_DIP_ENABLE) {
 			val &= ~VIDEO_DIP_ENABLE;