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From: Philippe CORNU <philippe.cornu@st.com>
To: Alexandre Torgue <alexandre.torgue@st.com>, Thierry Reding
	<thierry.reding@gmail.com>, David Airlie <airlied@linux.ie>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Russell King <linux@armlinux.org.uk>, Mark
	Rutland <mark.rutland@arm.com>, Rob Herring <robh+dt@kernel.org>, Arnd
	Bergmann <arnd@arndb.de>,
	Benjamin Gaignard <benjamin.gaignard@linaro.org>,
	Yannick Fertre <yannick.fertre@st.com>, Archit Taneja
	<architt@codeaurora.org>, Andrzej Hajda <a.hajda@samsung.com>
Subject: [PATCH v2 3/3] drm/panel: Add support for otm8009a panel driver
Date: Mon, 10 Jul 2017 11:02:13 +0200
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Cc: linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
	Philippe Cornu <philippe.cornu@st.com>,
	Fabien Dessenne <fabien.dessenne@st.com>,
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This patch adds Orise Tech otm8009a 3.97" 480x800 TFT LCD
panel driver (MIPI-DSI video mode). The panel backlight is
managed through the DSI link. This panel driver is used in
several STM32 boards.

Signed-off-by: Philippe CORNU <philippe.cornu@st.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
---
 drivers/gpu/drm/panel/Kconfig                    |   9 +
 drivers/gpu/drm/panel/Makefile                   |   1 +
 drivers/gpu/drm/panel/panel-orisetech-otm8009a.c | 489 +++++++++++++++++++++++
 3 files changed, 499 insertions(+)
 create mode 100755 drivers/gpu/drm/panel/panel-orisetech-otm8009a.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index d84a031..c1c9291 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -117,4 +117,13 @@ config DRM_PANEL_SITRONIX_ST7789V
 	  Say Y here if you want to enable support for the Sitronix
 	  ST7789V controller for 240x320 LCD panels
 
+config DRM_PANEL_ORISETECH_OTM8009A
+	tristate "Orise Tech otm8009a 480p dsi 2dl video mode panel"
+	depends on OF
+	depends on DRM_MIPI_DSI
+	depends on BACKLIGHT_CLASS_DEVICE
+	help
+	  Say Y here if you want to enable support for Orise Tech OTM8009A
+	  480x800 DSI panel
+
 endmenu
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index 9f6610d..ac798f3 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -10,3 +10,4 @@ obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E8AA0) += panel-samsung-s6e8aa0.o
 obj-$(CONFIG_DRM_PANEL_SHARP_LQ101R1SX01) += panel-sharp-lq101r1sx01.o
 obj-$(CONFIG_DRM_PANEL_SHARP_LS043T1LE01) += panel-sharp-ls043t1le01.o
 obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7789V) += panel-sitronix-st7789v.o
+obj-$(CONFIG_DRM_PANEL_ORISETECH_OTM8009A) += panel-orisetech-otm8009a.o
\ No newline at end of file
diff --git a/drivers/gpu/drm/panel/panel-orisetech-otm8009a.c b/drivers/gpu/drm/panel/panel-orisetech-otm8009a.c
new file mode 100755
index 0000000..2a3ce47
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-orisetech-otm8009a.c
@@ -0,0 +1,489 @@
+/*
+ * Copyright (C) STMicroelectronics SA 2017
+ *
+ * Authors: Philippe Cornu <philippe.cornu@st.com>
+ *          Yannick Fertre <yannick.fertre@st.com>
+ *
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+#include <drm/drmP.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_panel.h>
+#include <linux/backlight.h>
+#include <linux/gpio/consumer.h>
+#include <video/mipi_display.h>
+
+#define DRV_NAME "orisetech_otm8009a"
+
+#define OTM8009A_BACKLIGHT_DEFAULT	240
+#define OTM8009A_BACKLIGHT_MAX		255
+
+/* Manufacturer Command Set */
+#define MCS_ADRSFT	0x0000	/* Address Shift Function */
+#define MCS_PANSET	0xB3A6	/* Panel Type Setting */
+#define MCS_SD_CTRL	0xC0A2	/* Source Driver Timing Setting */
+#define MCS_P_DRV_M	0xC0B4	/* Panel Driving Mode */
+#define MCS_OSC_ADJ	0xC181	/* Oscillator Adjustment for Idle/Normal mode */
+#define MCS_RGB_VID_SET	0xC1A1	/* RGB Video Mode Setting */
+#define MCS_SD_PCH_CTRL	0xC480	/* Source Driver Precharge Control */
+#define MCS_NO_DOC1	0xC48A	/* Command not documented */
+#define MCS_PWR_CTRL1	0xC580	/* Power Control Setting 1 */
+#define MCS_PWR_CTRL2	0xC590	/* Power Control Setting 2 for Normal Mode */
+#define MCS_PWR_CTRL4	0xC5B0	/* Power Control Setting 4 for DC Voltage */
+#define MCS_PANCTRLSET1	0xCB80	/* Panel Control Setting 1 */
+#define MCS_PANCTRLSET2	0xCB90	/* Panel Control Setting 2 */
+#define MCS_PANCTRLSET3	0xCBA0	/* Panel Control Setting 3 */
+#define MCS_PANCTRLSET4	0xCBB0	/* Panel Control Setting 4 */
+#define MCS_PANCTRLSET5	0xCBC0	/* Panel Control Setting 5 */
+#define MCS_PANCTRLSET6	0xCBD0	/* Panel Control Setting 6 */
+#define MCS_PANCTRLSET7	0xCBE0	/* Panel Control Setting 7 */
+#define MCS_PANCTRLSET8	0xCBF0	/* Panel Control Setting 8 */
+#define MCS_PANU2D1	0xCC80	/* Panel U2D Setting 1 */
+#define MCS_PANU2D2	0xCC90	/* Panel U2D Setting 2 */
+#define MCS_PANU2D3	0xCCA0	/* Panel U2D Setting 3 */
+#define MCS_PAND2U1	0xCCB0	/* Panel D2U Setting 1 */
+#define MCS_PAND2U2	0xCCC0	/* Panel D2U Setting 2 */
+#define MCS_PAND2U3	0xCCD0	/* Panel D2U Setting 3 */
+#define MCS_GOAVST	0xCE80	/* GOA VST Setting */
+#define MCS_GOACLKA1	0xCEA0	/* GOA CLKA1 Setting */
+#define MCS_GOACLKA3	0xCEB0	/* GOA CLKA3 Setting */
+#define MCS_GOAECLK	0xCFC0	/* GOA ECLK Setting */
+#define MCS_NO_DOC2	0xCFD0	/* Command not documented */
+#define MCS_GVDDSET	0xD800	/* GVDD/NGVDD */
+#define MCS_VCOMDC	0xD900	/* VCOM Voltage Setting */
+#define MCS_GMCT2_2P	0xE100	/* Gamma Correction 2.2+ Setting */
+#define MCS_GMCT2_2N	0xE200	/* Gamma Correction 2.2- Setting */
+#define MCS_NO_DOC3	0xF5B6	/* Command not documented */
+#define MCS_CMD2_ENA1	0xFF00	/* Enable Access Command2 "CMD2" */
+#define MCS_CMD2_ENA2	0xFF80	/* Enable Access Orise Command2 */
+
+struct otm8009a {
+	struct device *dev;
+	struct drm_panel panel;
+	struct backlight_device *bl_dev;
+	struct gpio_desc *reset_gpio;
+	bool prepared;
+	bool enabled;
+};
+
+static const struct drm_display_mode default_mode = {
+	.clock = 32729,
+	.hdisplay = 480,
+	.hsync_start = 480 + 120,
+	.hsync_end = 480 + 120 + 63,
+	.htotal = 480 + 120 + 63 + 120,
+	.vdisplay = 800,
+	.vsync_start = 800 + 12,
+	.vsync_end = 800 + 12 + 12,
+	.vtotal = 800 + 12 + 12 + 12,
+	.vrefresh = 50,
+	.flags = 0,
+	.width_mm = 52,
+	.height_mm = 86,
+};
+
+static inline struct otm8009a *panel_to_otm8009a(struct drm_panel *panel)
+{
+	return container_of(panel, struct otm8009a, panel);
+}
+
+static void otm8009a_dcs_write_buf(struct otm8009a *ctx, const void *data,
+				   size_t len)
+{
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
+
+	if (mipi_dsi_dcs_write_buffer(dsi, data, len) < 0)
+		DRM_WARN("mipi dsi dcs write buffer failed\n");
+}
+
+#define dcs_write_seq(ctx, seq...)			\
+({							\
+	static const u8 d[] = { seq };			\
+	otm8009a_dcs_write_buf(ctx, d, ARRAY_SIZE(d));	\
+})
+
+#define dcs_write_cmd_at(ctx, cmd, seq...)		\
+({							\
+	dcs_write_seq(ctx, MCS_ADRSFT, (cmd) & 0xFF);	\
+	dcs_write_seq(ctx, (cmd) >> 8, seq);		\
+})
+
+static int otm8009a_init_sequence(struct otm8009a *ctx)
+{
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
+	int ret;
+
+	/* Enter CMD2 */
+	dcs_write_cmd_at(ctx, MCS_CMD2_ENA1, 0x80, 0x09, 0x01);
+
+	/* Enter Orise Command2 */
+	dcs_write_cmd_at(ctx, MCS_CMD2_ENA2, 0x80, 0x09);
+
+	dcs_write_cmd_at(ctx, MCS_SD_PCH_CTRL, 0x30);
+	mdelay(10);
+
+	dcs_write_cmd_at(ctx, MCS_NO_DOC1, 0x40);
+	mdelay(10);
+
+	dcs_write_cmd_at(ctx, MCS_PWR_CTRL4 + 1, 0xA9);
+	dcs_write_cmd_at(ctx, MCS_PWR_CTRL2 + 1, 0x34);
+	dcs_write_cmd_at(ctx, MCS_P_DRV_M, 0x50);
+	dcs_write_cmd_at(ctx, MCS_VCOMDC, 0x4E);
+	dcs_write_cmd_at(ctx, MCS_OSC_ADJ, 0x66); /* 65Hz */
+	dcs_write_cmd_at(ctx, MCS_RGB_VID_SET, 0x08);
+	dcs_write_cmd_at(ctx, MCS_PWR_CTRL2 + 2, 0x01);
+	dcs_write_cmd_at(ctx, MCS_PWR_CTRL2 + 5, 0x34);
+	dcs_write_cmd_at(ctx, MCS_PWR_CTRL2 + 4, 0x33);
+	dcs_write_cmd_at(ctx, MCS_GVDDSET, 0x79, 0x79);
+	dcs_write_cmd_at(ctx, MCS_SD_CTRL + 1, 0x1B);
+	dcs_write_cmd_at(ctx, MCS_PWR_CTRL1 + 2, 0x83);
+	dcs_write_cmd_at(ctx, MCS_SD_PCH_CTRL + 1, 0x83);
+	dcs_write_cmd_at(ctx, MCS_RGB_VID_SET, 0x0E); /* FIXME before 0x08! */
+	dcs_write_cmd_at(ctx, MCS_PANSET, 0x00, 0x01);
+
+	dcs_write_cmd_at(ctx, MCS_GOAVST, 0x85, 0x01, 0x00, 0x84, 0x01, 0x00);
+	dcs_write_cmd_at(ctx, MCS_GOACLKA1, 0x18, 0x04, 0x03, 0x39, 0x00, 0x00,
+			 0x00, 0x18, 0x03, 0x03, 0x3A, 0x00, 0x00, 0x00);
+	dcs_write_cmd_at(ctx, MCS_GOACLKA3, 0x18, 0x02, 0x03, 0x3B, 0x00, 0x00,
+			 0x00, 0x18, 0x01, 0x03, 0x3C, 0x00, 0x00, 0x00);
+	dcs_write_cmd_at(ctx, MCS_GOAECLK, 0x01, 0x01, 0x20, 0x20, 0x00, 0x00,
+			 0x01, 0x02, 0x00, 0x00);
+
+	dcs_write_cmd_at(ctx, MCS_NO_DOC2, 0x00);
+
+	dcs_write_cmd_at(ctx, MCS_PANCTRLSET1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
+	dcs_write_cmd_at(ctx, MCS_PANCTRLSET2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+			 0, 0, 0, 0, 0);
+	dcs_write_cmd_at(ctx, MCS_PANCTRLSET3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+			 0, 0, 0, 0, 0);
+	dcs_write_cmd_at(ctx, MCS_PANCTRLSET4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
+	dcs_write_cmd_at(ctx, MCS_PANCTRLSET5, 0, 4, 4, 4, 4, 4, 0, 0, 0, 0,
+			 0, 0, 0, 0, 0);
+	dcs_write_cmd_at(ctx, MCS_PANCTRLSET6, 0, 0, 0, 0, 0, 0, 4, 4, 4, 4,
+			 4, 0, 0, 0, 0);
+	dcs_write_cmd_at(ctx, MCS_PANCTRLSET7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
+	dcs_write_cmd_at(ctx, MCS_PANCTRLSET8, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+			 0xFF, 0xFF, 0xFF, 0xFF, 0xFF);
+
+	dcs_write_cmd_at(ctx, MCS_PANU2D1, 0x00, 0x26, 0x09, 0x0B, 0x01, 0x25,
+			 0x00, 0x00, 0x00, 0x00);
+	dcs_write_cmd_at(ctx, MCS_PANU2D2, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			 0x00, 0x00, 0x00, 0x00, 0x00, 0x26, 0x0A, 0x0C, 0x02);
+	dcs_write_cmd_at(ctx, MCS_PANU2D3, 0x25, 0x00, 0x00, 0x00, 0x00, 0x00,
+			 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
+	dcs_write_cmd_at(ctx, MCS_PAND2U1, 0x00, 0x25, 0x0C, 0x0A, 0x02, 0x26,
+			 0x00, 0x00, 0x00, 0x00);
+	dcs_write_cmd_at(ctx, MCS_PAND2U2, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			 0x00, 0x00, 0x00, 0x00, 0x00, 0x25, 0x0B, 0x09, 0x01);
+	dcs_write_cmd_at(ctx, MCS_PAND2U3, 0x26, 0x00, 0x00, 0x00, 0x00, 0x00,
+			 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
+
+	dcs_write_cmd_at(ctx, MCS_PWR_CTRL1 + 1, 0x66);
+
+	dcs_write_cmd_at(ctx, MCS_NO_DOC3, 0x06);
+
+	dcs_write_cmd_at(ctx, MCS_GMCT2_2P, 0x00, 0x09, 0x0F, 0x0E, 0x07, 0x10,
+			 0x0B, 0x0A, 0x04, 0x07, 0x0B, 0x08, 0x0F, 0x10, 0x0A,
+			 0x01);
+	dcs_write_cmd_at(ctx, MCS_GMCT2_2N, 0x00, 0x09, 0x0F, 0x0E, 0x07, 0x10,
+			 0x0B, 0x0A, 0x04, 0x07, 0x0B, 0x08, 0x0F, 0x10, 0x0A,
+			 0x01);
+
+	/* Exit CMD2 */
+	dcs_write_cmd_at(ctx, MCS_CMD2_ENA1, 0xFF, 0xFF, 0xFF);
+
+	ret = mipi_dsi_dcs_nop(dsi);
+	if (ret)
+		return ret;
+
+	ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
+	if (ret)
+		return ret;
+
+	/* Wait for sleep out exit */
+	mdelay(120);
+
+	/* Default portrait 480x800 rgb24 */
+	dcs_write_seq(ctx, MIPI_DCS_SET_ADDRESS_MODE, 0x00);
+
+	ret = mipi_dsi_dcs_set_column_address(dsi, 0,
+					      default_mode.hdisplay - 1);
+	if (ret)
+		return ret;
+
+	ret = mipi_dsi_dcs_set_page_address(dsi, 0, default_mode.vdisplay - 1);
+	if (ret)
+		return ret;
+
+	/* See otm8009a driver documentation for pixel format descriptions */
+	ret = mipi_dsi_dcs_set_pixel_format(dsi, MIPI_DCS_PIXEL_FMT_24BIT |
+					    MIPI_DCS_PIXEL_FMT_24BIT << 4);
+	if (ret)
+		return ret;
+
+	/* Disable CABC feature */
+	dcs_write_seq(ctx, MIPI_DCS_WRITE_POWER_SAVE, 0x00);
+
+	ret = mipi_dsi_dcs_set_display_on(dsi);
+	if (ret)
+		return ret;
+
+	ret = mipi_dsi_dcs_nop(dsi);
+	if (ret)
+		return ret;
+
+	/* Send Command GRAM memory write (no parameters) */
+	dcs_write_seq(ctx, MIPI_DCS_WRITE_MEMORY_START);
+
+	return 0;
+}
+
+static int otm8009a_disable(struct drm_panel *panel)
+{
+	struct otm8009a *ctx = panel_to_otm8009a(panel);
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
+	int ret;
+
+	if (!ctx->enabled)
+		return 0; /* This is not an issue so we return 0 here */
+
+	/* Power off the backlight. Note: end-user still controls brightness */
+	ctx->bl_dev->props.power = FB_BLANK_POWERDOWN;
+	ret = backlight_update_status(ctx->bl_dev);
+	if (ret)
+		return ret;
+
+	ret = mipi_dsi_dcs_set_display_off(dsi);
+	if (ret < 0)
+		return ret;
+
+	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
+	if (ret < 0)
+		return ret;
+
+	msleep(120);
+
+	ctx->enabled = false;
+
+	return 0;
+}
+
+static int otm8009a_unprepare(struct drm_panel *panel)
+{
+	struct otm8009a *ctx = panel_to_otm8009a(panel);
+
+	if (!ctx->prepared)
+		return 0;
+
+	if (ctx->reset_gpio) {
+		gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+		msleep(20);
+	}
+
+	ctx->prepared = false;
+
+	return 0;
+}
+
+static int otm8009a_prepare(struct drm_panel *panel)
+{
+	struct otm8009a *ctx = panel_to_otm8009a(panel);
+	int ret;
+
+	if (ctx->prepared)
+		return 0;
+
+	if (ctx->reset_gpio) {
+		gpiod_set_value_cansleep(ctx->reset_gpio, 0);
+		gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+		msleep(20);
+		gpiod_set_value_cansleep(ctx->reset_gpio, 0);
+		msleep(100);
+	}
+
+	ret = otm8009a_init_sequence(ctx);
+	if (ret)
+		return ret;
+
+	ctx->prepared = true;
+
+	/* Power on the backlight. Note: end-user still controls brightness */
+	ctx->bl_dev->props.power = FB_BLANK_UNBLANK;
+	backlight_update_status(ctx->bl_dev);
+
+	return 0;
+}
+
+static int otm8009a_enable(struct drm_panel *panel)
+{
+	struct otm8009a *ctx = panel_to_otm8009a(panel);
+
+	ctx->enabled = true;
+
+	return 0;
+}
+
+static int otm8009a_get_modes(struct drm_panel *panel)
+{
+	struct drm_display_mode *mode;
+
+	mode = drm_mode_duplicate(panel->drm, &default_mode);
+	if (!mode) {
+		DRM_ERROR("failed to add mode %ux%ux@%u\n",
+			  default_mode.hdisplay, default_mode.vdisplay,
+			  default_mode.vrefresh);
+		return -ENOMEM;
+	}
+
+	drm_mode_set_name(mode);
+
+	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
+	drm_mode_probed_add(panel->connector, mode);
+
+	panel->connector->display_info.width_mm = mode->width_mm;
+	panel->connector->display_info.height_mm = mode->height_mm;
+
+	return 1;
+}
+
+static const struct drm_panel_funcs otm8009a_drm_funcs = {
+	.disable   = otm8009a_disable,
+	.unprepare = otm8009a_unprepare,
+	.prepare   = otm8009a_prepare,
+	.enable    = otm8009a_enable,
+	.get_modes = otm8009a_get_modes,
+};
+
+/*
+ * DSI-BASED BACKLIGHT
+ */
+
+static int otm8009a_backlight_update_status(struct backlight_device *bd)
+{
+	struct otm8009a *ctx = bl_get_data(bd);
+	u8 data[2];
+
+	if (!ctx->prepared) {
+		DRM_DEBUG("lcd not ready yet for setting its backlight!\n");
+		return -ENXIO;
+	}
+
+	if (bd->props.power <= FB_BLANK_NORMAL) {
+		/* Power on the backlight with the requested brightness
+		 * Note We can not use mipi_dsi_dcs_set_display_brightness()
+		 * as otm8009a driver support only 8-bit brightness (1 param).
+		 */
+		data[0] = MIPI_DCS_SET_DISPLAY_BRIGHTNESS;
+		data[1] = bd->props.brightness;
+		otm8009a_dcs_write_buf(ctx, data, ARRAY_SIZE(data));
+
+		/* set Brightness Control & Backlight on */
+		data[1] = 0x24;
+
+	} else {
+		/* Power off the backlight: set Brightness Control & Bl off */
+		data[1] = 0;
+	}
+
+	/* Update Brightness Control & Backlight */
+	data[0] = MIPI_DCS_WRITE_CONTROL_DISPLAY;
+	otm8009a_dcs_write_buf(ctx, data, ARRAY_SIZE(data));
+
+	return 0;
+}
+
+static const struct backlight_ops otm8009a_backlight_ops = {
+	.update_status = otm8009a_backlight_update_status,
+};
+
+static int otm8009a_probe(struct mipi_dsi_device *dsi)
+{
+	struct device *dev = &dsi->dev;
+	struct otm8009a *ctx;
+	int ret;
+
+	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(ctx->reset_gpio)) {
+		dev_err(dev, "cannot get reset-gpio\n");
+		return PTR_ERR(ctx->reset_gpio);
+	}
+
+	mipi_dsi_set_drvdata(dsi, ctx);
+
+	ctx->dev = dev;
+
+	dsi->lanes = 2;
+	dsi->format = MIPI_DSI_FMT_RGB888;
+	dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
+			  MIPI_DSI_MODE_LPM;
+
+	drm_panel_init(&ctx->panel);
+	ctx->panel.dev = dev;
+	ctx->panel.funcs = &otm8009a_drm_funcs;
+
+	ctx->bl_dev = backlight_device_register(DRV_NAME "_backlight", dev, ctx,
+						&otm8009a_backlight_ops, NULL);
+	if (IS_ERR(ctx->bl_dev)) {
+		dev_err(dev, "failed to register backlight device\n");
+		return PTR_ERR(ctx->bl_dev);
+	}
+
+	ctx->bl_dev->props.max_brightness = OTM8009A_BACKLIGHT_MAX;
+	ctx->bl_dev->props.brightness = OTM8009A_BACKLIGHT_DEFAULT;
+	ctx->bl_dev->props.power = FB_BLANK_POWERDOWN;
+	ctx->bl_dev->props.type = BACKLIGHT_RAW;
+
+	drm_panel_add(&ctx->panel);
+
+	ret = mipi_dsi_attach(dsi);
+	if (ret < 0) {
+		dev_err(dev, "mipi_dsi_attach failed. Is host ready?\n");
+		drm_panel_remove(&ctx->panel);
+		backlight_device_unregister(ctx->bl_dev);
+		return ret;
+	}
+
+	DRM_INFO(DRV_NAME "_panel %ux%u@%u %ubpp dsi %udl - ready\n",
+		 default_mode.hdisplay, default_mode.vdisplay,
+		 default_mode.vrefresh,
+		 mipi_dsi_pixel_format_to_bpp(dsi->format), dsi->lanes);
+
+	return 0;
+}
+
+static int otm8009a_remove(struct mipi_dsi_device *dsi)
+{
+	struct otm8009a *ctx = mipi_dsi_get_drvdata(dsi);
+
+	mipi_dsi_detach(dsi);
+	drm_panel_remove(&ctx->panel);
+
+	backlight_device_unregister(ctx->bl_dev);
+
+	return 0;
+}
+
+static const struct of_device_id orisetech_otm8009a_of_match[] = {
+	{ .compatible = "orisetech,otm8009a" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, orisetech_otm8009a_of_match);
+
+static struct mipi_dsi_driver orisetech_otm8009a_driver = {
+	.probe  = otm8009a_probe,
+	.remove = otm8009a_remove,
+	.driver = {
+		.name = DRV_NAME "_panel",
+		.of_match_table = orisetech_otm8009a_of_match,
+	},
+};
+module_mipi_dsi_driver(orisetech_otm8009a_driver);
+
+MODULE_AUTHOR("Philippe Cornu <philippe.cornu@st.com>");
+MODULE_AUTHOR("Yannick Fertre <yannick.fertre@st.com>");
+MODULE_DESCRIPTION("DRM driver for Orise Tech OTM8009A MIPI DSI panel");
+MODULE_LICENSE("GPL v2");