drm/vc4: dsi: Add support for DSI0

DSI0 was partially supported, but didn't register with the main
driver, and the code was inconsistent as to whether it checked
port == 0 or port == 1.

Add compatible string and other support to make it consistent.
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20201203132543.861591-6-maxime@cerno.tech

drivers/gpu/drm/vc4/vc4_dsi.c

@@ -1324,6 +1324,13 @@ static const struct drm_encoder_helper_funcs vc4_dsi_encoder_helper_funcs = {
 	.mode_fixup = vc4_dsi_encoder_mode_fixup,
 };
 
+static const struct vc4_dsi_variant bcm2835_dsi0_variant = {
+	.port			= 0,
+	.debugfs_name		= "dsi0_regs",
+	.regs			= dsi0_regs,
+	.nregs			= ARRAY_SIZE(dsi0_regs),
+};
+
 static const struct vc4_dsi_variant bcm2835_dsi1_variant = {
 	.port			= 1,
 	.broken_axi_workaround	= true,
@@ -1333,6 +1340,7 @@ static const struct vc4_dsi_variant bcm2835_dsi1_variant = {
 };
 
 static const struct of_device_id vc4_dsi_dt_match[] = {
+	{ .compatible = "brcm,bcm2835-dsi0", &bcm2835_dsi0_variant },
 	{ .compatible = "brcm,bcm2835-dsi1", &bcm2835_dsi1_variant },
 	{}
 };