drm: rcar-du: Add R8A7796 support

Document the R8A7796-specific DT bindings and support them in the
driver. The HDMI output is currently not supported.

Signed-off-by: Laurent Pinchart <[e-mail]>

Documentation/devicetree/bindings/display/renesas,du.txt

···
     - "renesas,du-r8a7793" for R8A7793 (R-Car M2-N) compatible DU
     - "renesas,du-r8a7794" for R8A7794 (R-Car E2) compatible DU
     - "renesas,du-r8a7795" for R8A7795 (R-Car H3) compatible DU
+    - "renesas,du-r8a7796" for R8A7796 (R-Car M3-W) compatible DU
 
   - reg: A list of base address and length of each memory resource, one for
     each entry in the reg-names property.
···
   - clock-names: Name of the clocks. This property is model-dependent.
     - R8A7779 uses a single functional clock. The clock doesn't need to be
       named.
-    - R8A779[012345] use one functional clock per channel and one clock per LVDS
-      encoder (if available). The functional clocks must be named "du.x" with
-      "x" being the channel numerical index. The LVDS clocks must be named
-      "lvds.x" with "x" being the LVDS encoder numerical index.
+    - R8A779[0123456] use one functional clock per channel and one clock per
+      LVDS encoder (if available). The functional clocks must be named "du.x"
+      with "x" being the channel numerical index. The LVDS clocks must be
+      named "lvds.x" with "x" being the LVDS encoder numerical index.
     - In addition to the functional and encoder clocks, all DU versions also
       support externally supplied pixel clocks. Those clocks are optional.
       When supplied they must be named "dclkin.x" with "x" being the input
···
  R8A7793 (M2-N)	DPAD		LVDS 0		-		-
  R8A7794 (E2)	DPAD 0		DPAD 1		-		-
  R8A7795 (H3)	DPAD		HDMI 0		HDMI 1		LVDS
+ R8A7796 (M3-W)	DPAD		HDMI		LVDS		-
 
 
 Example: R8A7790 (R-Car H2) DU

drivers/gpu/drm/rcar-du/rcar_du_drv.c

···
 	.num_lvds = 1,
 };
 
+static const struct rcar_du_device_info rcar_du_r8a7796_info = {
+	.gen = 3,
+	.features = RCAR_DU_FEATURE_CRTC_IRQ_CLOCK
+		  | RCAR_DU_FEATURE_EXT_CTRL_REGS
+		  | RCAR_DU_FEATURE_VSP1_SOURCE,
+	.num_crtcs = 3,
+	.routes = {
+		/* R8A7796 has one RGB output, one LVDS output and one
+		 * (currently unsupported) HDMI output.
+		 */
+		[RCAR_DU_OUTPUT_DPAD0] = {
+			.possible_crtcs = BIT(2),
+			.encoder_type = DRM_MODE_ENCODER_NONE,
+			.port = 0,
+		},
+		[RCAR_DU_OUTPUT_LVDS0] = {
+			.possible_crtcs = BIT(0),
+			.encoder_type = DRM_MODE_ENCODER_LVDS,
+			.port = 2,
+		},
+	},
+	.num_lvds = 1,
+};
+
 static const struct of_device_id rcar_du_of_table[] = {
 	{ .compatible = "renesas,du-r8a7779", .data = &rcar_du_r8a7779_info },
 	{ .compatible = "renesas,du-r8a7790", .data = &rcar_du_r8a7790_info },
···
 	{ .compatible = "renesas,du-r8a7793", .data = &rcar_du_r8a7791_info },
 	{ .compatible = "renesas,du-r8a7794", .data = &rcar_du_r8a7794_info },
 	{ .compatible = "renesas,du-r8a7795", .data = &rcar_du_r8a7795_info },
+	{ .compatible = "renesas,du-r8a7796", .data = &rcar_du_r8a7796_info },
 	{ }
 };