drm: bridge: samsung-dsim: Add i.MX8M Plus support

Add extras to support i.MX8M Plus. The main change is the removal of
HS/VS/DE signal inversion in the LCDIFv3-DSIM glue logic, otherwise
the implementation of this IP in i.MX8M Plus is very much compatible
with the i.MX8M Mini/Nano one.
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Acked-by: Robert Foss <robert.foss@linaro.org>
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Inki Dae <m.szyprowski@samsung.com>

drivers/gpu/drm/bridge/samsung-dsim.c

@@ -479,6 +479,7 @@ samsung_dsim_types[DSIM_TYPE_COUNT] = {
 	[DSIM_TYPE_EXYNOS5422] = &exynos5422_dsi_driver_data,
 	[DSIM_TYPE_EXYNOS5433] = &exynos5433_dsi_driver_data,
 	[DSIM_TYPE_IMX8MM] = &imx8mm_dsi_driver_data,
+	[DSIM_TYPE_IMX8MP] = &imx8mm_dsi_driver_data,
 };
 
 static inline struct samsung_dsim *host_to_dsi(struct mipi_dsi_host *h)
@@ -1452,10 +1453,17 @@ static int samsung_dsim_atomic_check(struct drm_bridge *bridge,
 	 * 13.6.2.7.2 RGB interface
 	 * both claim "Vsync, Hsync, and VDEN are active high signals.", the
 	 * LCDIF must generate inverted HS/VS/DE signals, i.e. active LOW.
+	 *
+	 * The i.MX8M Plus glue logic between LCDIFv3 and DSIM does not
+	 * implement the same behavior, therefore LCDIFv3 must generate
+	 * HS/VS/DE signals active HIGH.
 	 */
 	if (dsi->plat_data->hw_type == DSIM_TYPE_IMX8MM) {
 		adjusted_mode->flags |= (DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
 		adjusted_mode->flags &= ~(DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
+	} else if (dsi->plat_data->hw_type == DSIM_TYPE_IMX8MP) {
+		adjusted_mode->flags &= ~(DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
+		adjusted_mode->flags |= (DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
 	}
 
 	return 0;
@@ -1723,6 +1731,10 @@ static const struct samsung_dsim_host_ops generic_dsim_host_ops = {
 	.unregister_host = generic_dsim_unregister_host,
 };
 
+static const struct drm_bridge_timings samsung_dsim_bridge_timings_de_high = {
+	.input_bus_flags = DRM_BUS_FLAG_DE_HIGH,
+};
+
 static const struct drm_bridge_timings samsung_dsim_bridge_timings_de_low = {
 	.input_bus_flags = DRM_BUS_FLAG_DE_LOW,
 };
@@ -1812,6 +1824,8 @@ int samsung_dsim_probe(struct platform_device *pdev)
 	/* DE_LOW: i.MX8M Mini/Nano LCDIF-DSIM glue logic inverts HS/VS/DE */
 	if (dsi->plat_data->hw_type == DSIM_TYPE_IMX8MM)
 		dsi->bridge.timings = &samsung_dsim_bridge_timings_de_low;
+	else
+		dsi->bridge.timings = &samsung_dsim_bridge_timings_de_high;
 
 	if (dsi->plat_data->host_ops && dsi->plat_data->host_ops->register_host)
 		ret = dsi->plat_data->host_ops->register_host(dsi);
@@ -1917,11 +1931,20 @@ static const struct samsung_dsim_plat_data samsung_dsim_imx8mm_pdata = {
 	.host_ops = &generic_dsim_host_ops,
 };
 
+static const struct samsung_dsim_plat_data samsung_dsim_imx8mp_pdata = {
+	.hw_type = DSIM_TYPE_IMX8MP,
+	.host_ops = &generic_dsim_host_ops,
+};
+
 static const struct of_device_id samsung_dsim_of_match[] = {
 	{
 		.compatible = "fsl,imx8mm-mipi-dsim",
 		.data = &samsung_dsim_imx8mm_pdata,
 	},
+	{
+		.compatible = "fsl,imx8mp-mipi-dsim",
+		.data = &samsung_dsim_imx8mp_pdata,
+	},
 	{ /* sentinel. */ }
 };
 MODULE_DEVICE_TABLE(of, samsung_dsim_of_match);

include/drm/bridge/samsung-dsim.h

@@ -28,6 +28,7 @@ enum samsung_dsim_type {
 	DSIM_TYPE_EXYNOS5422,
 	DSIM_TYPE_EXYNOS5433,
 	DSIM_TYPE_IMX8MM,
+	DSIM_TYPE_IMX8MP,
 	DSIM_TYPE_COUNT,
 };