[PATCH v2 2/2] drm/panel: Add Sony Tulip Truly NT35521 driver

[Shawn Guo <shawn.guo@linaro.org>]

It adds a DRM panel driver for Sony Tulip Truly NT35521 5.24" 1280x720
DSI panel, which can be found on Sony Xperia M4 Aqua phone.  The panel
backlight is managed through DSI link.

The driver is built using linux-mdss-dsi-panel-driver-generator[1], and
additionally modeling the 5V control GPIOs with regulators and adding
Backlight GPIO support.

[1] https://github.com/msm8916-mainline/linux-mdss-dsi-panel-driver-generator

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
---
 drivers/gpu/drm/panel/Kconfig                 |  10 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 .../panel/panel-sony-tulip-truly-nt35521.c    | 552 ++++++++++++++++++
 3 files changed, 563 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index ef87d92cdf49..a5809eab49b2 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -502,6 +502,16 @@ config DRM_PANEL_SONY_ACX565AKM
 	  Say Y here if you want to enable support for the Sony ACX565AKM
 	  800x600 3.5" panel (found on the Nokia N900).
 
+config DRM_PANEL_SONY_TULIP_TRULY_NT35521
+	tristate "Sony Tulip Truly NT35521 panel"
+	depends on GPIOLIB && OF
+	depends on DRM_MIPI_DSI
+	depends on BACKLIGHT_CLASS_DEVICE
+	help
+	  Say Y here if you want to enable support for the Sony Tulip
+	  NT35521 1280x720 video mode panel as found on Sony Xperia M4
+	  Aqua phone.
+
 config DRM_PANEL_TDO_TL070WSH30
 	tristate "TDO TL070WSH30 DSI panel"
 	depends on OF
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index cae4d976c069..852ce32d58ee 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7703) += panel-sitronix-st7703.o
 obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7789V) += panel-sitronix-st7789v.o
 obj-$(CONFIG_DRM_PANEL_SONY_ACX424AKP) += panel-sony-acx424akp.o
 obj-$(CONFIG_DRM_PANEL_SONY_ACX565AKM) += panel-sony-acx565akm.o
+obj-$(CONFIG_DRM_PANEL_SONY_TULIP_TRULY_NT35521) += panel-sony-tulip-truly-nt35521.o
 obj-$(CONFIG_DRM_PANEL_TDO_TL070WSH30) += panel-tdo-tl070wsh30.o
 obj-$(CONFIG_DRM_PANEL_TPO_TD028TTEC1) += panel-tpo-td028ttec1.o
 obj-$(CONFIG_DRM_PANEL_TPO_TD043MTEA1) += panel-tpo-td043mtea1.o
diff --git a/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c b/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c
new file mode 100644
index 000000000000..eba926c6f722
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c
@@ -0,0 +1,552 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2021, Linaro Limited
+ *
+ * Generated with linux-mdss-dsi-panel-driver-generator from vendor device tree:
+ *   Copyright (c) 2013, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regulator/consumer.h>
+
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+
+struct truly_nt35521 {
+	struct drm_panel panel;
+	struct mipi_dsi_device *dsi;
+	struct regulator_bulk_data supplies[2];
+	struct gpio_desc *reset_gpio;
+	struct gpio_desc *blen_gpio;
+	bool prepared;
+	bool enabled;
+};
+
+static inline
+struct truly_nt35521 *to_truly_nt35521(struct drm_panel *panel)
+{
+	return container_of(panel, struct truly_nt35521, panel);
+}
+
+#define dsi_generic_write_seq(dsi, seq...) do {				\
+		static const u8 d[] = { seq };				\
+		int ret;						\
+		ret = mipi_dsi_generic_write(dsi, d, ARRAY_SIZE(d));	\
+		if (ret < 0)						\
+			return ret;					\
+	} while (0)
+
+static void truly_nt35521_reset(struct truly_nt35521 *ctx)
+{
+	gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+	usleep_range(1000, 2000);
+	gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+	usleep_range(10000, 11000);
+	gpiod_set_value_cansleep(ctx->reset_gpio, 0);
+	msleep(150);
+}
+
+static int truly_nt35521_on(struct truly_nt35521 *ctx)
+{
+	struct mipi_dsi_device *dsi = ctx->dsi;
+	struct device *dev = &dsi->dev;
+	int ret;
+
+	dsi->mode_flags |= MIPI_DSI_MODE_LPM;
+
+	dsi_generic_write_seq(dsi, 0xf0, 0x55, 0xaa, 0x52, 0x08, 0x00);
+	dsi_generic_write_seq(dsi, 0xff, 0xaa, 0x55, 0xa5, 0x80);
+	dsi_generic_write_seq(dsi, 0x6f, 0x11, 0x00);
+	dsi_generic_write_seq(dsi, 0xf7, 0x20, 0x00);
+	dsi_generic_write_seq(dsi, 0x6f, 0x01);
+	dsi_generic_write_seq(dsi, 0xb1, 0x21);
+	dsi_generic_write_seq(dsi, 0xbd, 0x01, 0xa0, 0x10, 0x08, 0x01);
+	dsi_generic_write_seq(dsi, 0xb8, 0x01, 0x02, 0x0c, 0x02);
+	dsi_generic_write_seq(dsi, 0xbb, 0x11, 0x11);
+	dsi_generic_write_seq(dsi, 0xbc, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xb6, 0x02);
+	dsi_generic_write_seq(dsi, 0xf0, 0x55, 0xaa, 0x52, 0x08, 0x01);
+	dsi_generic_write_seq(dsi, 0xb0, 0x09, 0x09);
+	dsi_generic_write_seq(dsi, 0xb1, 0x09, 0x09);
+	dsi_generic_write_seq(dsi, 0xbc, 0x8c, 0x00);
+	dsi_generic_write_seq(dsi, 0xbd, 0x8c, 0x00);
+	dsi_generic_write_seq(dsi, 0xca, 0x00);
+	dsi_generic_write_seq(dsi, 0xc0, 0x04);
+	dsi_generic_write_seq(dsi, 0xbe, 0xb5);
+	dsi_generic_write_seq(dsi, 0xb3, 0x35, 0x35);
+	dsi_generic_write_seq(dsi, 0xb4, 0x25, 0x25);
+	dsi_generic_write_seq(dsi, 0xb9, 0x43, 0x43);
+	dsi_generic_write_seq(dsi, 0xba, 0x24, 0x24);
+	dsi_generic_write_seq(dsi, 0xf0, 0x55, 0xaa, 0x52, 0x08, 0x02);
+	dsi_generic_write_seq(dsi, 0xee, 0x03);
+	dsi_generic_write_seq(dsi, 0xb0,
+			      0x00, 0xb2, 0x00, 0xb3, 0x00, 0xb6, 0x00, 0xc3,
+			      0x00, 0xce, 0x00, 0xe1, 0x00, 0xf3, 0x01, 0x11);
+	dsi_generic_write_seq(dsi, 0xb1,
+			      0x01, 0x2e, 0x01, 0x5c, 0x01, 0x82, 0x01, 0xc3,
+			      0x01, 0xfe, 0x02, 0x00, 0x02, 0x37, 0x02, 0x77);
+	dsi_generic_write_seq(dsi, 0xb2,
+			      0x02, 0xa1, 0x02, 0xd7, 0x02, 0xfe, 0x03, 0x2c,
+			      0x03, 0x4b, 0x03, 0x63, 0x03, 0x8f, 0x03, 0x90);
+	dsi_generic_write_seq(dsi, 0xb3, 0x03, 0x96, 0x03, 0x98);
+	dsi_generic_write_seq(dsi, 0xb4,
+			      0x00, 0x81, 0x00, 0x8b, 0x00, 0x9c, 0x00, 0xa9,
+			      0x00, 0xb5, 0x00, 0xcb, 0x00, 0xdf, 0x01, 0x02);
+	dsi_generic_write_seq(dsi, 0xb5,
+			      0x01, 0x1f, 0x01, 0x51, 0x01, 0x7a, 0x01, 0xbf,
+			      0x01, 0xfa, 0x01, 0xfc, 0x02, 0x34, 0x02, 0x76);
+	dsi_generic_write_seq(dsi, 0xb6,
+			      0x02, 0x9f, 0x02, 0xd7, 0x02, 0xfc, 0x03, 0x2c,
+			      0x03, 0x4a, 0x03, 0x63, 0x03, 0x8f, 0x03, 0xa2);
+	dsi_generic_write_seq(dsi, 0xb7, 0x03, 0xb8, 0x03, 0xba);
+	dsi_generic_write_seq(dsi, 0xb8,
+			      0x00, 0x01, 0x00, 0x02, 0x00, 0x0e, 0x00, 0x2a,
+			      0x00, 0x41, 0x00, 0x67, 0x00, 0x87, 0x00, 0xb9);
+	dsi_generic_write_seq(dsi, 0xb9,
+			      0x00, 0xe2, 0x01, 0x22, 0x01, 0x54, 0x01, 0xa3,
+			      0x01, 0xe6, 0x01, 0xe7, 0x02, 0x24, 0x02, 0x67);
+	dsi_generic_write_seq(dsi, 0xba,
+			      0x02, 0x93, 0x02, 0xcd, 0x02, 0xf6, 0x03, 0x31,
+			      0x03, 0x6c, 0x03, 0xe9, 0x03, 0xef, 0x03, 0xf4);
+	dsi_generic_write_seq(dsi, 0xbb, 0x03, 0xf6, 0x03, 0xf7);
+	dsi_generic_write_seq(dsi, 0xf0, 0x55, 0xaa, 0x52, 0x08, 0x03);
+	dsi_generic_write_seq(dsi, 0xb0, 0x22, 0x00);
+	dsi_generic_write_seq(dsi, 0xb1, 0x22, 0x00);
+	dsi_generic_write_seq(dsi, 0xb2, 0x05, 0x00, 0x60, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xb3, 0x05, 0x00, 0x60, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xb4, 0x05, 0x00, 0x60, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xb5, 0x05, 0x00, 0x60, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xba, 0x53, 0x00, 0x60, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xbb, 0x53, 0x00, 0x60, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xbc, 0x53, 0x00, 0x60, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xbd, 0x53, 0x00, 0x60, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xc0, 0x00, 0x34, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xc1, 0x00, 0x00, 0x34, 0x00);
+	dsi_generic_write_seq(dsi, 0xc2, 0x00, 0x00, 0x34, 0x00);
+	dsi_generic_write_seq(dsi, 0xc3, 0x00, 0x00, 0x34, 0x00);
+	dsi_generic_write_seq(dsi, 0xc4, 0x60);
+	dsi_generic_write_seq(dsi, 0xc5, 0xc0);
+	dsi_generic_write_seq(dsi, 0xc6, 0x00);
+	dsi_generic_write_seq(dsi, 0xc7, 0x00);
+	dsi_generic_write_seq(dsi, 0xf0, 0x55, 0xaa, 0x52, 0x08, 0x05);
+	dsi_generic_write_seq(dsi, 0xb0, 0x17, 0x06);
+	dsi_generic_write_seq(dsi, 0xb1, 0x17, 0x06);
+	dsi_generic_write_seq(dsi, 0xb2, 0x17, 0x06);
+	dsi_generic_write_seq(dsi, 0xb3, 0x17, 0x06);
+	dsi_generic_write_seq(dsi, 0xb4, 0x17, 0x06);
+	dsi_generic_write_seq(dsi, 0xb5, 0x17, 0x06);
+	dsi_generic_write_seq(dsi, 0xb6, 0x17, 0x06);
+	dsi_generic_write_seq(dsi, 0xb7, 0x17, 0x06);
+	dsi_generic_write_seq(dsi, 0xb8, 0x00);
+	dsi_generic_write_seq(dsi, 0xb9, 0x00, 0x03);
+	dsi_generic_write_seq(dsi, 0xba, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xbb, 0x02, 0x03);
+	dsi_generic_write_seq(dsi, 0xbc, 0x02, 0x03);
+	dsi_generic_write_seq(dsi, 0xbd, 0x03, 0x03, 0x00, 0x03, 0x03);
+	dsi_generic_write_seq(dsi, 0xc0, 0x0b);
+	dsi_generic_write_seq(dsi, 0xc1, 0x09);
+	dsi_generic_write_seq(dsi, 0xc2, 0xa6);
+	dsi_generic_write_seq(dsi, 0xc3, 0x05);
+	dsi_generic_write_seq(dsi, 0xc4, 0x00);
+	dsi_generic_write_seq(dsi, 0xc5, 0x02);
+	dsi_generic_write_seq(dsi, 0xc6, 0x22);
+	dsi_generic_write_seq(dsi, 0xc7, 0x03);
+	dsi_generic_write_seq(dsi, 0xc8, 0x07, 0x20);
+	dsi_generic_write_seq(dsi, 0xc9, 0x03, 0x20);
+	dsi_generic_write_seq(dsi, 0xca, 0x01, 0x60);
+	dsi_generic_write_seq(dsi, 0xcb, 0x01, 0x60);
+	dsi_generic_write_seq(dsi, 0xcc, 0x00, 0x00, 0x02);
+	dsi_generic_write_seq(dsi, 0xcd, 0x00, 0x00, 0x02);
+	dsi_generic_write_seq(dsi, 0xce, 0x00, 0x00, 0x02);
+	dsi_generic_write_seq(dsi, 0xcf, 0x00, 0x00, 0x02);
+	dsi_generic_write_seq(dsi, 0xd1, 0x00, 0x05, 0x01, 0x07, 0x10);
+	dsi_generic_write_seq(dsi, 0xd2, 0x10, 0x05, 0x05, 0x03, 0x10);
+	dsi_generic_write_seq(dsi, 0xd3, 0x20, 0x00, 0x43, 0x07, 0x10);
+	dsi_generic_write_seq(dsi, 0xd4, 0x30, 0x00, 0x43, 0x07, 0x10);
+	dsi_generic_write_seq(dsi, 0xd0,
+			      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xd5,
+			      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			      0x00, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xd6,
+			      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			      0x00, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xd7,
+			      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			      0x00, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xd8, 0x00, 0x00, 0x00, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xe5, 0x06);
+	dsi_generic_write_seq(dsi, 0xe6, 0x06);
+	dsi_generic_write_seq(dsi, 0xe7, 0x00);
+	dsi_generic_write_seq(dsi, 0xe8, 0x06);
+	dsi_generic_write_seq(dsi, 0xe9, 0x06);
+	dsi_generic_write_seq(dsi, 0xea, 0x06);
+	dsi_generic_write_seq(dsi, 0xeb, 0x00);
+	dsi_generic_write_seq(dsi, 0xec, 0x00);
+	dsi_generic_write_seq(dsi, 0xed, 0x30);
+	dsi_generic_write_seq(dsi, 0xf0, 0x55, 0xaa, 0x52, 0x08, 0x06);
+	dsi_generic_write_seq(dsi, 0xb0, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xb1, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xb2, 0x2d, 0x2e);
+	dsi_generic_write_seq(dsi, 0xb3, 0x31, 0x34);
+	dsi_generic_write_seq(dsi, 0xb4, 0x29, 0x2a);
+	dsi_generic_write_seq(dsi, 0xb5, 0x12, 0x10);
+	dsi_generic_write_seq(dsi, 0xb6, 0x18, 0x16);
+	dsi_generic_write_seq(dsi, 0xb7, 0x00, 0x02);
+	dsi_generic_write_seq(dsi, 0xb8, 0x08, 0x31);
+	dsi_generic_write_seq(dsi, 0xb9, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xba, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xbb, 0x31, 0x08);
+	dsi_generic_write_seq(dsi, 0xbc, 0x03, 0x01);
+	dsi_generic_write_seq(dsi, 0xbd, 0x17, 0x19);
+	dsi_generic_write_seq(dsi, 0xbe, 0x11, 0x13);
+	dsi_generic_write_seq(dsi, 0xbf, 0x2a, 0x29);
+	dsi_generic_write_seq(dsi, 0xc0, 0x34, 0x31);
+	dsi_generic_write_seq(dsi, 0xc1, 0x2e, 0x2d);
+	dsi_generic_write_seq(dsi, 0xc2, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xc3, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xc4, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xc5, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xc6, 0x2e, 0x2d);
+	dsi_generic_write_seq(dsi, 0xc7, 0x31, 0x34);
+	dsi_generic_write_seq(dsi, 0xc8, 0x29, 0x2a);
+	dsi_generic_write_seq(dsi, 0xc9, 0x17, 0x19);
+	dsi_generic_write_seq(dsi, 0xca, 0x11, 0x13);
+	dsi_generic_write_seq(dsi, 0xcb, 0x03, 0x01);
+	dsi_generic_write_seq(dsi, 0xcc, 0x08, 0x31);
+	dsi_generic_write_seq(dsi, 0xcd, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xce, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xcf, 0x31, 0x08);
+	dsi_generic_write_seq(dsi, 0xd0, 0x00, 0x02);
+	dsi_generic_write_seq(dsi, 0xd1, 0x12, 0x10);
+	dsi_generic_write_seq(dsi, 0xd2, 0x18, 0x16);
+	dsi_generic_write_seq(dsi, 0xd3, 0x2a, 0x29);
+	dsi_generic_write_seq(dsi, 0xd4, 0x34, 0x31);
+	dsi_generic_write_seq(dsi, 0xd5, 0x2d, 0x2e);
+	dsi_generic_write_seq(dsi, 0xd6, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xd7, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xe5, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xe6, 0x31, 0x31);
+	dsi_generic_write_seq(dsi, 0xd8, 0x00, 0x00, 0x00, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xd9, 0x00, 0x00, 0x00, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xe7, 0x00);
+	dsi_generic_write_seq(dsi, 0x6f, 0x02);
+	dsi_generic_write_seq(dsi, 0xf7, 0x47);
+	dsi_generic_write_seq(dsi, 0x6f, 0x0a);
+	dsi_generic_write_seq(dsi, 0xf7, 0x02);
+	dsi_generic_write_seq(dsi, 0x6f, 0x17);
+	dsi_generic_write_seq(dsi, 0xf4, 0x60);
+	dsi_generic_write_seq(dsi, 0x6f, 0x01);
+	dsi_generic_write_seq(dsi, 0xf9, 0x46);
+	dsi_generic_write_seq(dsi, 0x6f, 0x11);
+	dsi_generic_write_seq(dsi, 0xf3, 0x01);
+	dsi_generic_write_seq(dsi, 0x35, 0x00);
+	dsi_generic_write_seq(dsi, 0xf0, 0x55, 0xaa, 0x52, 0x08, 0x00);
+	dsi_generic_write_seq(dsi, 0xd9, 0x02, 0x03, 0x00);
+	dsi_generic_write_seq(dsi, 0xf0, 0x55, 0xaa, 0x52, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0xf0, 0x55, 0xaa, 0x52, 0x08, 0x00);
+	dsi_generic_write_seq(dsi, 0xb1, 0x6c, 0x21);
+	dsi_generic_write_seq(dsi, 0xf0, 0x55, 0xaa, 0x52, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, 0x35, 0x00);
+
+	ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
+	if (ret < 0) {
+		dev_err(dev, "Failed to exit sleep mode: %d\n", ret);
+		return ret;
+	}
+	msleep(120);
+
+	ret = mipi_dsi_dcs_set_display_on(dsi);
+	if (ret < 0) {
+		dev_err(dev, "Failed to set display on: %d\n", ret);
+		return ret;
+	}
+	usleep_range(1000, 2000);
+
+	dsi_generic_write_seq(dsi, 0x53, 0x24);
+
+	return 0;
+}
+
+static int truly_nt35521_off(struct truly_nt35521 *ctx)
+{
+	struct mipi_dsi_device *dsi = ctx->dsi;
+	struct device *dev = &dsi->dev;
+	int ret;
+
+	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
+
+	ret = mipi_dsi_dcs_set_display_off(dsi);
+	if (ret < 0) {
+		dev_err(dev, "Failed to set display off: %d\n", ret);
+		return ret;
+	}
+	msleep(50);
+
+	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
+	if (ret < 0) {
+		dev_err(dev, "Failed to enter sleep mode: %d\n", ret);
+		return ret;
+	}
+	msleep(150);
+
+	return 0;
+}
+
+static int truly_nt35521_prepare(struct drm_panel *panel)
+{
+	struct truly_nt35521 *ctx = to_truly_nt35521(panel);
+	struct device *dev = &ctx->dsi->dev;
+	int ret;
+
+	if (ctx->prepared)
+		return 0;
+
+	ret = regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
+	if (ret < 0) {
+		dev_err(dev, "Failed to enable regulators: %d\n", ret);
+		return ret;
+	}
+
+	truly_nt35521_reset(ctx);
+
+	ret = truly_nt35521_on(ctx);
+	if (ret < 0) {
+		dev_err(dev, "Failed to initialize panel: %d\n", ret);
+		gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+		return ret;
+	}
+
+	ctx->prepared = true;
+	return 0;
+}
+
+static int truly_nt35521_unprepare(struct drm_panel *panel)
+{
+	struct truly_nt35521 *ctx = to_truly_nt35521(panel);
+	struct device *dev = &ctx->dsi->dev;
+	int ret;
+
+	if (!ctx->prepared)
+		return 0;
+
+	ret = truly_nt35521_off(ctx);
+	if (ret < 0)
+		dev_err(dev, "Failed to un-initialize panel: %d\n", ret);
+
+	gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+	regulator_bulk_disable(ARRAY_SIZE(ctx->supplies),
+			       ctx->supplies);
+
+	ctx->prepared = false;
+	return 0;
+}
+
+static int truly_nt35521_enable(struct drm_panel *panel)
+{
+	struct truly_nt35521 *ctx = to_truly_nt35521(panel);
+
+	if (ctx->enabled)
+		return 0;
+
+	gpiod_set_value_cansleep(ctx->blen_gpio, 1);
+
+	ctx->enabled = true;
+	return 0;
+}
+
+static int truly_nt35521_disable(struct drm_panel *panel)
+{
+	struct truly_nt35521 *ctx = to_truly_nt35521(panel);
+
+	if (!ctx->enabled)
+		return 0;
+
+	gpiod_set_value_cansleep(ctx->blen_gpio, 0);
+
+	ctx->enabled = false;
+	return 0;
+}
+
+static const struct drm_display_mode truly_nt35521_mode = {
+	.clock = (720 + 232 + 20 + 112) * (1280 + 18 + 1 + 18) * 60 / 1000,
+	.hdisplay = 720,
+	.hsync_start = 720 + 232,
+	.hsync_end = 720 + 232 + 20,
+	.htotal = 720 + 232 + 20 + 112,
+	.vdisplay = 1280,
+	.vsync_start = 1280 + 18,
+	.vsync_end = 1280 + 18 + 1,
+	.vtotal = 1280 + 18 + 1 + 18,
+	.width_mm = 65,
+	.height_mm = 116,
+};
+
+static int truly_nt35521_get_modes(struct drm_panel *panel,
+				     struct drm_connector *connector)
+{
+	struct drm_display_mode *mode;
+
+	mode = drm_mode_duplicate(connector->dev, &truly_nt35521_mode);
+	if (!mode)
+		return -ENOMEM;
+
+	drm_mode_set_name(mode);
+
+	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
+	connector->display_info.width_mm = mode->width_mm;
+	connector->display_info.height_mm = mode->height_mm;
+	drm_mode_probed_add(connector, mode);
+
+	return 1;
+}
+
+static const struct drm_panel_funcs truly_nt35521_panel_funcs = {
+	.prepare = truly_nt35521_prepare,
+	.unprepare = truly_nt35521_unprepare,
+	.enable = truly_nt35521_enable,
+	.disable = truly_nt35521_disable,
+	.get_modes = truly_nt35521_get_modes,
+};
+
+static int truly_nt35521_bl_update_status(struct backlight_device *bl)
+{
+	struct mipi_dsi_device *dsi = bl_get_data(bl);
+	u16 brightness = backlight_get_brightness(bl);
+	int ret;
+
+	ret = mipi_dsi_dcs_set_display_brightness(dsi, brightness);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int truly_nt35521_bl_get_brightness(struct backlight_device *bl)
+{
+	struct mipi_dsi_device *dsi = bl_get_data(bl);
+	u16 brightness;
+	int ret;
+
+	ret = mipi_dsi_dcs_get_display_brightness(dsi, &brightness);
+	if (ret < 0)
+		return ret;
+
+	return brightness & 0xff;
+}
+
+static const struct backlight_ops truly_nt35521_bl_ops = {
+	.update_status = truly_nt35521_bl_update_status,
+	.get_brightness = truly_nt35521_bl_get_brightness,
+};
+
+static struct backlight_device *
+truly_nt35521_create_backlight(struct mipi_dsi_device *dsi)
+{
+	struct device *dev = &dsi->dev;
+	const struct backlight_properties props = {
+		.type = BACKLIGHT_RAW,
+		.brightness = 255,
+		.max_brightness = 255,
+	};
+
+	return devm_backlight_device_register(dev, dev_name(dev), dev, dsi,
+					      &truly_nt35521_bl_ops, &props);
+}
+
+static int truly_nt35521_probe(struct mipi_dsi_device *dsi)
+{
+	struct device *dev = &dsi->dev;
+	struct truly_nt35521 *ctx;
+	int ret;
+
+	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->supplies[0].supply = "positive5";
+	ctx->supplies[1].supply = "negative5";
+	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ctx->supplies),
+				      ctx->supplies);
+	if (ret < 0) {
+		dev_err(dev, "Failed to get regulators: %d\n", ret);
+		return ret;
+	}
+
+	ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(ctx->reset_gpio))
+		return dev_err_probe(dev, PTR_ERR(ctx->reset_gpio),
+				     "Failed to get reset-gpios\n");
+
+	ctx->blen_gpio = devm_gpiod_get(dev, "backlight", GPIOD_OUT_LOW);
+	if (IS_ERR(ctx->blen_gpio))
+		return dev_err_probe(dev, PTR_ERR(ctx->blen_gpio),
+				     "Failed to get backlight-gpios\n");
+
+	ctx->dsi = dsi;
+	mipi_dsi_set_drvdata(dsi, ctx);
+
+	dsi->lanes = 4;
+	dsi->format = MIPI_DSI_FMT_RGB888;
+	dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
+			  MIPI_DSI_MODE_VIDEO_HSE | MIPI_DSI_MODE_EOT_PACKET |
+			  MIPI_DSI_CLOCK_NON_CONTINUOUS;
+
+	drm_panel_init(&ctx->panel, dev, &truly_nt35521_panel_funcs,
+		       DRM_MODE_CONNECTOR_DSI);
+
+	ctx->panel.backlight = truly_nt35521_create_backlight(dsi);
+	if (IS_ERR(ctx->panel.backlight))
+		return dev_err_probe(dev, PTR_ERR(ctx->panel.backlight),
+				     "Failed to create backlight\n");
+
+	drm_panel_add(&ctx->panel);
+
+	ret = mipi_dsi_attach(dsi);
+	if (ret < 0) {
+		dev_err(dev, "Failed to attach to DSI host: %d\n", ret);
+		drm_panel_remove(&ctx->panel);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int truly_nt35521_remove(struct mipi_dsi_device *dsi)
+{
+	struct truly_nt35521 *ctx = mipi_dsi_get_drvdata(dsi);
+	int ret;
+
+	ret = mipi_dsi_detach(dsi);
+	if (ret < 0)
+		dev_err(&dsi->dev, "Failed to detach from DSI host: %d\n", ret);
+
+	drm_panel_remove(&ctx->panel);
+
+	return 0;
+}
+
+static const struct of_device_id truly_nt35521_of_match[] = {
+	{ .compatible = "sony,tulip-truly-nt35521" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, truly_nt35521_of_match);
+
+static struct mipi_dsi_driver truly_nt35521_driver = {
+	.probe = truly_nt35521_probe,
+	.remove = truly_nt35521_remove,
+	.driver = {
+		.name = "panel-truly-nt35521",
+		.of_match_table = truly_nt35521_of_match,
+	},
+};
+module_mipi_dsi_driver(truly_nt35521_driver);
+
+MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>");
+MODULE_DESCRIPTION("DRM driver for Sony Tulip Truly NT35521 panel");
+MODULE_LICENSE("GPL v2");
-- 
2.17.1