drm/ssd130x: Add support for the SSD133x OLED controller family

The Solomon SSD133x controllers (such as the SSD1331) are used by RGB dot
matrix OLED panels, add a modesetting pipeline to support the chip family.

The SSD133x controllers support 256 (8-bit) and 65k (16-bit) color depths
but only the 256-color mode (DRM_FORMAT_RGB332) is implemented for now.
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231229112026.2797483-5-javierm@redhat.com

drivers/gpu/drm/solomon/ssd130x-spi.c

@@ -142,6 +142,11 @@ static const struct of_device_id ssd130x_of_match[] = {
 		.compatible = "solomon,ssd1327",
 		.data = &ssd130x_variants[SSD1327_ID],
 	},
+	/* ssd133x family */
+	{
+		.compatible = "solomon,ssd1331",
+		.data = &ssd130x_variants[SSD1331_ID],
+	},
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, ssd130x_of_match);
@@ -166,6 +171,8 @@ static const struct spi_device_id ssd130x_spi_table[] = {
 	{ "ssd1322", SSD1322_ID },
 	{ "ssd1325", SSD1325_ID },
 	{ "ssd1327", SSD1327_ID },
+	/* ssd133x family */
+	{ "ssd1331", SSD1331_ID },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(spi, ssd130x_spi_table);

drivers/gpu/drm/solomon/ssd130x.h

@@ -25,7 +25,8 @@
 
 enum ssd130x_family_ids {
 	SSD130X_FAMILY,
-	SSD132X_FAMILY
+	SSD132X_FAMILY,
+	SSD133X_FAMILY
 };
 
 enum ssd130x_variants {
@@ -39,6 +40,8 @@ enum ssd130x_variants {
 	SSD1322_ID,
 	SSD1325_ID,
 	SSD1327_ID,
+	/* ssd133x family */
+	SSD1331_ID,
 	NR_SSD130X_VARIANTS
 };