drm/panel: simple: Support TI nspire panels

This adds support for the TI nspire panels to the simple panel
roster. This code is based on arch/arm/mach-nspire/clcd.c.
This includes likely the first grayscale panel supported.

These panels will be used with the PL11x DRM driver.

Cc: Daniel Tang <dt.tangr@gmail.com>
Cc: Fabian Vogt <fabian@ritter-vogt.de>
Tested-by: Fabian Vogt <fabian@ritter-vogt.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190805085847.25554-4-linus.walleij@linaro.org

drivers/gpu/drm/panel/panel-simple.c

@@ -2833,6 +2833,64 @@ static const struct panel_desc tianma_tm070rvhg71 = {
 	.bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,
 };
 
+static const struct drm_display_mode ti_nspire_cx_lcd_mode[] = {
+	{
+		.clock = 10000,
+		.hdisplay = 320,
+		.hsync_start = 320 + 50,
+		.hsync_end = 320 + 50 + 6,
+		.htotal = 320 + 50 + 6 + 38,
+		.vdisplay = 240,
+		.vsync_start = 240 + 3,
+		.vsync_end = 240 + 3 + 1,
+		.vtotal = 240 + 3 + 1 + 17,
+		.vrefresh = 60,
+		.flags = DRM_MODE_FLAG_NVSYNC | DRM_MODE_FLAG_NHSYNC,
+	},
+};
+
+static const struct panel_desc ti_nspire_cx_lcd_panel = {
+	.modes = ti_nspire_cx_lcd_mode,
+	.num_modes = 1,
+	.bpc = 8,
+	.size = {
+		.width = 65,
+		.height = 49,
+	},
+	.bus_format = MEDIA_BUS_FMT_RGB888_1X24,
+	.bus_flags = DRM_BUS_FLAG_PIXDATA_NEGEDGE,
+};
+
+static const struct drm_display_mode ti_nspire_classic_lcd_mode[] = {
+	{
+		.clock = 10000,
+		.hdisplay = 320,
+		.hsync_start = 320 + 6,
+		.hsync_end = 320 + 6 + 6,
+		.htotal = 320 + 6 + 6 + 6,
+		.vdisplay = 240,
+		.vsync_start = 240 + 0,
+		.vsync_end = 240 + 0 + 1,
+		.vtotal = 240 + 0 + 1 + 0,
+		.vrefresh = 60,
+		.flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC,
+	},
+};
+
+static const struct panel_desc ti_nspire_classic_lcd_panel = {
+	.modes = ti_nspire_classic_lcd_mode,
+	.num_modes = 1,
+	/* The grayscale panel has 8 bit for the color .. Y (black) */
+	.bpc = 8,
+	.size = {
+		.width = 71,
+		.height = 53,
+	},
+	/* This is the grayscale bus format */
+	.bus_format = MEDIA_BUS_FMT_Y8_1X8,
+	.bus_flags = DRM_BUS_FLAG_PIXDATA_POSEDGE,
+};
+
 static const struct drm_display_mode toshiba_lt089ac29000_mode = {
 	.clock = 79500,
 	.hdisplay = 1280,
@@ -3302,6 +3360,12 @@ static const struct of_device_id platform_of_match[] = {
 	}, {
 		.compatible = "tianma,tm070rvhg71",
 		.data = &tianma_tm070rvhg71,
+	}, {
+		.compatible = "ti,nspire-cx-lcd-panel",
+		.data = &ti_nspire_cx_lcd_panel,
+	}, {
+		.compatible = "ti,nspire-classic-lcd-panel",
+		.data = &ti_nspire_classic_lcd_panel,
 	}, {
 		.compatible = "toshiba,lt089ac29000",
 		.data = &toshiba_lt089ac29000,