[PATCH v4 2/5] drm/panel: add Novatek NT36850 panel driver

[Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>]

Add support for the Truly WQHD dual-DSI command mode panel built around
the Novatek NT36850, found on the display card for the Qualcomm SDM845
and SM8150 HDK. The driver is based on panel-novatek-nt36523, the power
and command sequences follow the vendor device tree.

Assisted-by: LLM
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---
 drivers/gpu/drm/panel/Kconfig                 |  10 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 drivers/gpu/drm/panel/panel-novatek-nt36850.c | 351 ++++++++++++++++++++++++++
 3 files changed, 362 insertions(+)

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index 53a1fc2913fe..869a5501e709 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -723,6 +723,16 @@ config DRM_PANEL_NOVATEK_NT36672E
 	  LCD panel module. The panel has a resolution of 1080x2408 and uses 24 bit
 	  RGB per pixel.
 
+config DRM_PANEL_NOVATEK_NT36850
+	tristate "Novatek NT36850 panel driver"
+	depends on OF
+	depends on DRM_MIPI_DSI
+	depends on BACKLIGHT_CLASS_DEVICE
+	help
+	  Say Y here if you want to enable support for the panels built
+	  around the Novatek NT36850 display controller, such as some
+	  Truly panels used in Qualcomm development kits.
+
 config DRM_PANEL_NOVATEK_NT37700F
 	tristate "Novatek NT37700F DSI panel"
 	depends on OF
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index f2c9c80a218f..8dd8eb7080cb 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -69,6 +69,7 @@ obj-$(CONFIG_DRM_PANEL_NOVATEK_NT36532) += panel-novatek-nt36532.o
 obj-$(CONFIG_DRM_PANEL_NOVATEK_NT36536) += panel-novatek-nt36536.o
 obj-$(CONFIG_DRM_PANEL_NOVATEK_NT36672A) += panel-novatek-nt36672a.o
 obj-$(CONFIG_DRM_PANEL_NOVATEK_NT36672E) += panel-novatek-nt36672e.o
+obj-$(CONFIG_DRM_PANEL_NOVATEK_NT36850) += panel-novatek-nt36850.o
 obj-$(CONFIG_DRM_PANEL_NOVATEK_NT37700F) += panel-novatek-nt37700f.o
 obj-$(CONFIG_DRM_PANEL_NOVATEK_NT37801) += panel-novatek-nt37801.o
 obj-$(CONFIG_DRM_PANEL_NOVATEK_NT39016) += panel-novatek-nt39016.o
diff --git a/drivers/gpu/drm/panel/panel-novatek-nt36850.c b/drivers/gpu/drm/panel/panel-novatek-nt36850.c
new file mode 100644
index 000000000000..214ac81b006f
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-novatek-nt36850.c
@@ -0,0 +1,351 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Novatek NT36850 DriverIC panels driver
+ *
+ * Copyright (c) 2022, 2023 Jianhua Lu <lujianhua000@gmail.com>
+ * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/regulator/consumer.h>
+
+#include <video/mipi_display.h>
+
+#include <drm/drm_crtc.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_probe_helper.h>
+
+struct panel_info {
+	struct drm_panel panel;
+	struct mipi_dsi_device *dsi[2];
+	const struct panel_desc *desc;
+	enum drm_panel_orientation orientation;
+
+	struct gpio_desc *reset_gpio;
+	struct regulator *vddio;
+	struct regulator *avdd;
+	struct regulator *avee;
+};
+
+struct panel_desc {
+	unsigned int bpc;
+	unsigned int lanes;
+	unsigned long mode_flags;
+	enum mipi_dsi_pixel_format format;
+
+	const struct drm_display_mode *mode;
+	int (*init_sequence)(struct panel_info *pinfo);
+
+	bool is_dual_dsi;
+};
+
+static inline struct panel_info *to_panel_info(struct drm_panel *panel)
+{
+	return container_of(panel, struct panel_info, panel);
+}
+
+static int truly_wqhd_init_sequence(struct panel_info *pinfo)
+{
+	struct mipi_dsi_device *dsi0 = pinfo->dsi[0];
+	struct mipi_dsi_device *dsi1 = pinfo->dsi[1];
+	struct mipi_dsi_multi_context dsi_ctx = { .dsi = NULL };
+
+	mipi_dsi_dual_dcs_write_seq_multi(&dsi_ctx, dsi0, dsi1, 0xff, 0x10);
+	mipi_dsi_dual_dcs_write_seq_multi(&dsi_ctx, dsi0, dsi1, 0xfb, 0x01);
+	mipi_dsi_dual_dcs_write_seq_multi(&dsi_ctx, dsi0, dsi1,
+					  MIPI_DCS_SET_ADDRESS_MODE, 0x00);
+	mipi_dsi_dual(mipi_dsi_dcs_set_tear_on_multi, &dsi_ctx, dsi0, dsi1,
+		      MIPI_DSI_DCS_TEAR_MODE_VBLANK);
+	mipi_dsi_dual(mipi_dsi_dcs_set_tear_scanline_multi, &dsi_ctx, dsi0, dsi1,
+		      1000);
+	mipi_dsi_dual_dcs_write_seq_multi(&dsi_ctx, dsi0, dsi1,
+					  MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
+					  0xff);
+	mipi_dsi_dual_dcs_write_seq_multi(&dsi_ctx, dsi0, dsi1,
+					  MIPI_DCS_WRITE_CONTROL_DISPLAY,
+					  0x2c);
+	mipi_dsi_dual_dcs_write_seq_multi(&dsi_ctx, dsi0, dsi1,
+					  MIPI_DCS_WRITE_POWER_SAVE, 0x01);
+	mipi_dsi_dual_dcs_write_seq_multi(&dsi_ctx, dsi0, dsi1,
+					  MIPI_DCS_EXIT_INVERT_MODE);
+	mipi_dsi_usleep_range(&dsi_ctx, 10000, 11000);
+	mipi_dsi_dual_dcs_write_seq_multi(&dsi_ctx, dsi0, dsi1, 0xbb, 0x10);
+	mipi_dsi_dual(mipi_dsi_dcs_exit_sleep_mode_multi, &dsi_ctx, dsi0, dsi1);
+	mipi_dsi_msleep(&dsi_ctx, 120);
+	mipi_dsi_dual(mipi_dsi_dcs_set_display_on_multi, &dsi_ctx, dsi0, dsi1);
+	mipi_dsi_msleep(&dsi_ctx, 120);
+
+	return dsi_ctx.accum_err;
+}
+
+static const struct drm_display_mode truly_wqhd_mode = {
+	.clock = (720 + 120 + 20 + 140) * 2 * (2560 + 8 + 4 + 20) * 60 / 1000,
+	.hdisplay = 720 * 2,
+	.hsync_start = (720 + 120) * 2,
+	.hsync_end = (720 + 120 + 20) * 2,
+	.htotal = (720 + 120 + 20 + 140) * 2,
+	.vdisplay = 2560,
+	.vsync_start = 2560 + 8,
+	.vsync_end = 2560 + 8 + 4,
+	.vtotal = 2560 + 8 + 4 + 20,
+};
+
+static const struct panel_desc truly_wqhd_desc = {
+	.mode = &truly_wqhd_mode,
+	.bpc = 8,
+	.lanes = 4,
+	.format = MIPI_DSI_FMT_RGB888,
+	.mode_flags = MIPI_DSI_CLOCK_NON_CONTINUOUS | MIPI_DSI_MODE_LPM,
+	.init_sequence = truly_wqhd_init_sequence,
+	.is_dual_dsi = true,
+};
+
+static void nt36850_reset(struct panel_info *pinfo)
+{
+	gpiod_set_value_cansleep(pinfo->reset_gpio, 0);
+	usleep_range(10000, 11000);
+	gpiod_set_value_cansleep(pinfo->reset_gpio, 1);
+	usleep_range(10000, 11000);
+	gpiod_set_value_cansleep(pinfo->reset_gpio, 0);
+	msleep(50);
+}
+
+static int nt36850_prepare(struct drm_panel *panel)
+{
+	struct panel_info *pinfo = to_panel_info(panel);
+	int ret;
+
+	ret = regulator_enable(pinfo->vddio);
+	if (ret) {
+		dev_err(panel->dev, "failed to enable vddio regulator: %d\n", ret);
+		return ret;
+	}
+
+	msleep(20);
+
+	ret = regulator_enable(pinfo->avdd);
+	if (ret) {
+		dev_err(panel->dev, "failed to enable avdd regulator: %d\n", ret);
+		goto err_vddio;
+	}
+
+	ret = regulator_enable(pinfo->avee);
+	if (ret) {
+		dev_err(panel->dev, "failed to enable avee regulator: %d\n", ret);
+		goto err_avdd;
+	}
+
+	msleep(20);
+
+	nt36850_reset(pinfo);
+
+	ret = pinfo->desc->init_sequence(pinfo);
+	if (ret < 0) {
+		dev_err(panel->dev, "failed to initialize panel: %d\n", ret);
+		goto err_avee;
+	}
+
+	return 0;
+
+err_avee:
+	gpiod_set_value_cansleep(pinfo->reset_gpio, 1);
+	regulator_disable(pinfo->avee);
+err_avdd:
+	regulator_disable(pinfo->avdd);
+err_vddio:
+	regulator_disable(pinfo->vddio);
+
+	return ret;
+}
+
+static int nt36850_num_dsi_hosts(struct panel_info *pinfo)
+{
+	return pinfo->desc->is_dual_dsi ? 2 : 1;
+}
+
+static int nt36850_disable(struct drm_panel *panel)
+{
+	struct panel_info *pinfo = to_panel_info(panel);
+	struct mipi_dsi_device *dsi0 = pinfo->dsi[0];
+	struct mipi_dsi_device *dsi1 = pinfo->dsi[1];
+	struct mipi_dsi_multi_context dsi_ctx = { .dsi = NULL };
+
+	dsi0->mode_flags &= ~MIPI_DSI_MODE_LPM;
+	dsi1->mode_flags &= ~MIPI_DSI_MODE_LPM;
+
+	for (int i = 0; i < nt36850_num_dsi_hosts(pinfo); i++) {
+		struct mipi_dsi_multi_context dsi_ctx = { .dsi = pinfo->dsi[i]};
+
+		mipi_dsi_dcs_set_display_off_multi(&dsi_ctx);
+	}
+	mipi_dsi_msleep(&dsi_ctx, 120);
+
+	for (int i = 0; i < nt36850_num_dsi_hosts(pinfo); i++) {
+		struct mipi_dsi_multi_context dsi_ctx = { .dsi = pinfo->dsi[i]};
+
+		mipi_dsi_dcs_enter_sleep_mode_multi(&dsi_ctx);
+	}
+	mipi_dsi_msleep(&dsi_ctx, 120);
+
+	dsi0->mode_flags |= MIPI_DSI_MODE_LPM;
+	dsi1->mode_flags |= MIPI_DSI_MODE_LPM;
+
+	return dsi_ctx.accum_err;
+}
+
+static int nt36850_unprepare(struct drm_panel *panel)
+{
+	struct panel_info *pinfo = to_panel_info(panel);
+
+	gpiod_set_value_cansleep(pinfo->reset_gpio, 1);
+	regulator_disable(pinfo->avee);
+	regulator_disable(pinfo->avdd);
+	regulator_disable(pinfo->vddio);
+
+	return 0;
+}
+
+static int nt36850_get_modes(struct drm_panel *panel,
+			       struct drm_connector *connector)
+{
+	struct panel_info *pinfo = to_panel_info(panel);
+
+	connector->display_info.bpc = pinfo->desc->bpc;
+
+	return drm_connector_helper_get_modes_fixed(connector, pinfo->desc->mode);
+}
+
+static enum drm_panel_orientation nt36850_get_orientation(struct drm_panel *panel)
+{
+	struct panel_info *pinfo = to_panel_info(panel);
+
+	return pinfo->orientation;
+}
+
+static const struct drm_panel_funcs nt36850_panel_funcs = {
+	.disable = nt36850_disable,
+	.prepare = nt36850_prepare,
+	.unprepare = nt36850_unprepare,
+	.get_modes = nt36850_get_modes,
+	.get_orientation = nt36850_get_orientation,
+};
+
+static int nt36850_probe(struct mipi_dsi_device *dsi)
+{
+	struct device *dev = &dsi->dev;
+	struct device_node *dsi1;
+	struct mipi_dsi_host *dsi1_host;
+	struct panel_info *pinfo;
+	int i, ret;
+
+	pinfo = devm_drm_panel_alloc(dev, struct panel_info, panel,
+				     &nt36850_panel_funcs,
+				     DRM_MODE_CONNECTOR_DSI);
+	if (IS_ERR(pinfo))
+		return PTR_ERR(pinfo);
+
+	pinfo->vddio = devm_regulator_get(dev, "vddio");
+	if (IS_ERR(pinfo->vddio))
+		return dev_err_probe(dev, PTR_ERR(pinfo->vddio), "failed to get vddio regulator\n");
+
+	pinfo->avdd = devm_regulator_get(dev, "avdd");
+	if (IS_ERR(pinfo->avdd))
+		return dev_err_probe(dev, PTR_ERR(pinfo->avdd), "failed to get avdd regulator\n");
+
+	pinfo->avee = devm_regulator_get(dev, "avee");
+	if (IS_ERR(pinfo->avee))
+		return dev_err_probe(dev, PTR_ERR(pinfo->avee), "failed to get avee regulator\n");
+
+	pinfo->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(pinfo->reset_gpio))
+		return dev_err_probe(dev, PTR_ERR(pinfo->reset_gpio), "failed to get reset gpio\n");
+
+	pinfo->desc = of_device_get_match_data(dev);
+	if (!pinfo->desc)
+		return -ENODEV;
+
+	/* If the panel is dual dsi, register DSI1 */
+	if (pinfo->desc->is_dual_dsi) {
+		struct mipi_dsi_device_info dsi_info = {
+			.type = "dsi-secondary",
+		};
+
+		dsi1 = of_graph_get_remote_node(dsi->dev.of_node, 1, -1);
+		if (!dsi1) {
+			dev_err(dev, "cannot get secondary DSI node.\n");
+			return -ENODEV;
+		}
+
+		dsi1_host = of_find_mipi_dsi_host_by_node(dsi1);
+		of_node_put(dsi1);
+		if (!dsi1_host)
+			return dev_err_probe(dev, -EPROBE_DEFER, "cannot get secondary DSI host\n");
+
+		pinfo->dsi[1] = devm_mipi_dsi_device_register_full(dev, dsi1_host, &dsi_info);
+		if (IS_ERR(pinfo->dsi[1])) {
+			dev_err(dev, "cannot get secondary DSI device\n");
+			return PTR_ERR(pinfo->dsi[1]);
+		}
+	}
+
+	pinfo->dsi[0] = dsi;
+	mipi_dsi_set_drvdata(dsi, pinfo);
+
+	ret = drm_of_get_panel_orientation(dev->of_node, &pinfo->orientation);
+	if (ret < 0) {
+		dev_err(dev, "%pOF: failed to get orientation %d\n", dev->of_node, ret);
+		return ret;
+	}
+
+	pinfo->panel.prepare_prev_first = true;
+
+	ret = drm_panel_of_backlight(&pinfo->panel);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to get backlight\n");
+
+	ret = devm_drm_panel_add(&dsi->dev, &pinfo->panel);
+	if (ret)
+		return dev_err_probe(dev, ret, "can't add the panel\n");
+
+	for (i = 0; i < nt36850_num_dsi_hosts(pinfo); i++) {
+		pinfo->dsi[i]->lanes = pinfo->desc->lanes;
+		pinfo->dsi[i]->format = pinfo->desc->format;
+		pinfo->dsi[i]->mode_flags = pinfo->desc->mode_flags;
+
+		ret = devm_mipi_dsi_attach(dev, pinfo->dsi[i]);
+		if (ret < 0)
+			return dev_err_probe(dev, ret, "cannot attach to DSI%d host.\n", i);
+	}
+
+	return 0;
+}
+
+static const struct of_device_id nt36850_of_match[] = {
+	{
+		.compatible = "truly,wqhd60-nt36850",
+		.data = &truly_wqhd_desc,
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, nt36850_of_match);
+
+static struct mipi_dsi_driver nt36850_driver = {
+	.probe = nt36850_probe,
+	.driver = {
+		.name = "panel-novatek-nt36850",
+		.of_match_table = nt36850_of_match,
+	},
+};
+module_mipi_dsi_driver(nt36850_driver);
+
+MODULE_AUTHOR("Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>");
+MODULE_DESCRIPTION("DRM driver for Novatek NT36850 based MIPI DSI panels");
+MODULE_LICENSE("GPL");

-- 
2.47.3