drm/panel: add panel driver for Xinpeng XPP055C272 panels

Base on the somewhat similar Rocktech driver but adapted for
panel-specific init of the XPP055C272.

changes in v5:
- drop error message when backlight not found, no other panel
  does that and if needed it should live in drm_panel_of_backlight
changes in v4:
  none
changes in v3:
- remove wrong negative sync flags from display-mode to fix a display
  artifact of the output getting move a tiny bit to the right
changes in v2:
- move to drm-panel-internal backlight handling (Sam)
- adapt to changes that happened to drm_panel structs+functions (Sam)
- sort includes (Sam)
- drop unnecessary DRV_NAME constant (Sam)
- do mipi_dsi_dcs_exit_sleep_mode and mipi_dsi_dcs_set_display_on
  in panel prepare (not init_sequence) to keep symmetric (Sam)
Signed-off-by: Heiko Stuebner <heiko.stuebner@theobroma-systems.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191224112907.30758-3-heiko@sntech.de

drivers/gpu/drm/panel/Kconfig

@@ -366,4 +366,14 @@ config DRM_PANEL_TRULY_NT35597_WQXGA
 	help
 	  Say Y here if you want to enable support for Truly NT35597 WQXGA Dual DSI
 	  Video Mode panel
+
+config DRM_PANEL_XINPENG_XPP055C272
+	tristate "Xinpeng XPP055C272 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 Xinpeng
+	  XPP055C272 controller for 720x1280 LCD panels with MIPI/RGB/SPI
+	  system interfaces.
 endmenu

drivers/gpu/drm/panel/Makefile

@@ -39,3 +39,4 @@ obj-$(CONFIG_DRM_PANEL_TPO_TD028TTEC1) += panel-tpo-td028ttec1.o
 obj-$(CONFIG_DRM_PANEL_TPO_TD043MTEA1) += panel-tpo-td043mtea1.o
 obj-$(CONFIG_DRM_PANEL_TPO_TPG110) += panel-tpo-tpg110.o
 obj-$(CONFIG_DRM_PANEL_TRULY_NT35597_WQXGA) += panel-truly-nt35597.o
+obj-$(CONFIG_DRM_PANEL_XINPENG_XPP055C272) += panel-xinpeng-xpp055c272.o

drivers/gpu/drm/panel/panel-xinpeng-xpp055c272.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xinpeng xpp055c272 5.5" MIPI-DSI panel driver
+ * Copyright (C) 2019 Theobroma Systems Design und Consulting GmbH
+ *
+ * based on
+ *
+ * Rockteck jh057n00900 5.5" MIPI-DSI panel driver
+ * Copyright (C) Purism SPC 2019
+ */
+
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_print.h>
+
+#include <video/display_timing.h>
+#include <video/mipi_display.h>
+
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/media-bus-format.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regulator/consumer.h>
+
+/* Manufacturer specific Commands send via DSI */
+#define XPP055C272_CMD_ALL_PIXEL_OFF	0x22
+#define XPP055C272_CMD_ALL_PIXEL_ON	0x23
+#define XPP055C272_CMD_SETDISP		0xb2
+#define XPP055C272_CMD_SETRGBIF		0xb3
+#define XPP055C272_CMD_SETCYC		0xb4
+#define XPP055C272_CMD_SETBGP		0xb5
+#define XPP055C272_CMD_SETVCOM		0xb6
+#define XPP055C272_CMD_SETOTP		0xb7
+#define XPP055C272_CMD_SETPOWER_EXT	0xb8
+#define XPP055C272_CMD_SETEXTC		0xb9
+#define XPP055C272_CMD_SETMIPI		0xbA
+#define XPP055C272_CMD_SETVDC		0xbc
+#define XPP055C272_CMD_SETPCR		0xbf
+#define XPP055C272_CMD_SETSCR		0xc0
+#define XPP055C272_CMD_SETPOWER		0xc1
+#define XPP055C272_CMD_SETECO		0xc6
+#define XPP055C272_CMD_SETPANEL		0xcc
+#define XPP055C272_CMD_SETGAMMA		0xe0
+#define XPP055C272_CMD_SETEQ		0xe3
+#define XPP055C272_CMD_SETGIP1		0xe9
+#define XPP055C272_CMD_SETGIP2		0xea
+
+struct xpp055c272 {
+	struct device *dev;
+	struct drm_panel panel;
+	struct gpio_desc *reset_gpio;
+	struct regulator *vci;
+	struct regulator *iovcc;
+	bool prepared;
+};
+
+static inline struct xpp055c272 *panel_to_xpp055c272(struct drm_panel *panel)
+{
+	return container_of(panel, struct xpp055c272, panel);
+}
+
+#define dsi_generic_write_seq(dsi, cmd, seq...) do {			\
+		static const u8 d[] = { seq };				\
+		int ret;						\
+		ret = mipi_dsi_dcs_write(dsi, cmd, d, ARRAY_SIZE(d));	\
+		if (ret < 0)						\
+			return ret;					\
+	} while (0)
+
+static int xpp055c272_init_sequence(struct xpp055c272 *ctx)
+{
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
+	struct device *dev = ctx->dev;
+
+	/*
+	 * Init sequence was supplied by the panel vendor without much
+	 * documentation.
+	 */
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETEXTC, 0xf1, 0x12, 0x83);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETMIPI,
+			      0x33, 0x81, 0x05, 0xf9, 0x0e, 0x0e, 0x00, 0x00,
+			      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x44, 0x25,
+			      0x00, 0x91, 0x0a, 0x00, 0x00, 0x02, 0x4f, 0x01,
+			      0x00, 0x00, 0x37);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETPOWER_EXT, 0x25);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETPCR, 0x02, 0x11, 0x00);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETRGBIF,
+			      0x0c, 0x10, 0x0a, 0x50, 0x03, 0xff, 0x00, 0x00,
+			      0x00, 0x00);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETSCR,
+			      0x73, 0x73, 0x50, 0x50, 0x00, 0x00, 0x08, 0x70,
+			      0x00);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETVDC, 0x46);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETPANEL, 0x0b);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETCYC, 0x80);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETDISP, 0xc8, 0x12, 0x30);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETEQ,
+			      0x07, 0x07, 0x0B, 0x0B, 0x03, 0x0B, 0x00, 0x00,
+			      0x00, 0x00, 0xFF, 0x00, 0xC0, 0x10);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETPOWER,
+			      0x53, 0x00, 0x1e, 0x1e, 0x77, 0xe1, 0xcc, 0xdd,
+			      0x67, 0x77, 0x33, 0x33);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETECO, 0x00, 0x00, 0xff,
+			      0xff, 0x01, 0xff);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETBGP, 0x09, 0x09);
+	msleep(20);
+
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETVCOM, 0x87, 0x95);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETGIP1,
+			      0xc2, 0x10, 0x05, 0x05, 0x10, 0x05, 0xa0, 0x12,
+			      0x31, 0x23, 0x3f, 0x81, 0x0a, 0xa0, 0x37, 0x18,
+			      0x00, 0x80, 0x01, 0x00, 0x00, 0x00, 0x00, 0x80,
+			      0x01, 0x00, 0x00, 0x00, 0x48, 0xf8, 0x86, 0x42,
+			      0x08, 0x88, 0x88, 0x80, 0x88, 0x88, 0x88, 0x58,
+			      0xf8, 0x87, 0x53, 0x18, 0x88, 0x88, 0x81, 0x88,
+			      0x88, 0x88, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00,
+			      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETGIP2,
+			      0x00, 0x1a, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00,
+			      0x00, 0x00, 0x00, 0x00, 0x1f, 0x88, 0x81, 0x35,
+			      0x78, 0x88, 0x88, 0x85, 0x88, 0x88, 0x88, 0x0f,
+			      0x88, 0x80, 0x24, 0x68, 0x88, 0x88, 0x84, 0x88,
+			      0x88, 0x88, 0x23, 0x10, 0x00, 0x00, 0x1c, 0x00,
+			      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x30, 0x05,
+			      0xa0, 0x00, 0x00, 0x00, 0x00);
+	dsi_generic_write_seq(dsi, XPP055C272_CMD_SETGAMMA,
+			      0x00, 0x06, 0x08, 0x2a, 0x31, 0x3f, 0x38, 0x36,
+			      0x07, 0x0c, 0x0d, 0x11, 0x13, 0x12, 0x13, 0x11,
+			      0x18, 0x00, 0x06, 0x08, 0x2a, 0x31, 0x3f, 0x38,
+			      0x36, 0x07, 0x0c, 0x0d, 0x11, 0x13, 0x12, 0x13,
+			      0x11, 0x18);
+
+	msleep(60);
+
+	DRM_DEV_DEBUG_DRIVER(dev, "Panel init sequence done\n");
+	return 0;
+}
+
+static int xpp055c272_unprepare(struct drm_panel *panel)
+{
+	struct xpp055c272 *ctx = panel_to_xpp055c272(panel);
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
+	int ret;
+
+	if (!ctx->prepared)
+		return 0;
+
+	ret = mipi_dsi_dcs_set_display_off(dsi);
+	if (ret < 0)
+		DRM_DEV_ERROR(ctx->dev, "failed to set display off: %d\n",
+			      ret);
+
+	mipi_dsi_dcs_enter_sleep_mode(dsi);
+	if (ret < 0) {
+		DRM_DEV_ERROR(ctx->dev, "failed to enter sleep mode: %d\n",
+			      ret);
+		return ret;
+	}
+
+	regulator_disable(ctx->iovcc);
+	regulator_disable(ctx->vci);
+
+	ctx->prepared = false;
+
+	return 0;
+}
+
+static int xpp055c272_prepare(struct drm_panel *panel)
+{
+	struct xpp055c272 *ctx = panel_to_xpp055c272(panel);
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
+	int ret;
+
+	if (ctx->prepared)
+		return 0;
+
+	DRM_DEV_DEBUG_DRIVER(ctx->dev, "Resetting the panel\n");
+	ret = regulator_enable(ctx->vci);
+	if (ret < 0) {
+		DRM_DEV_ERROR(ctx->dev,
+			      "Failed to enable vci supply: %d\n", ret);
+		return ret;
+	}
+	ret = regulator_enable(ctx->iovcc);
+	if (ret < 0) {
+		DRM_DEV_ERROR(ctx->dev,
+			      "Failed to enable iovcc supply: %d\n", ret);
+		goto disable_vci;
+	}
+
+	gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+	/* T6: 10us */
+	usleep_range(10, 20);
+	gpiod_set_value_cansleep(ctx->reset_gpio, 0);
+
+	/* T8: 20ms */
+	msleep(20);
+
+	ret = xpp055c272_init_sequence(ctx);
+	if (ret < 0) {
+		DRM_DEV_ERROR(ctx->dev, "Panel init sequence failed: %d\n",
+			      ret);
+		goto disable_iovcc;
+	}
+
+	ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
+	if (ret < 0) {
+		DRM_DEV_ERROR(ctx->dev, "Failed to exit sleep mode: %d\n", ret);
+		goto disable_iovcc;
+	}
+
+	/* T9: 120ms */
+	msleep(120);
+
+	ret = mipi_dsi_dcs_set_display_on(dsi);
+	if (ret < 0) {
+		DRM_DEV_ERROR(ctx->dev, "Failed to set display on: %d\n", ret);
+		goto disable_iovcc;
+	}
+
+	msleep(50);
+
+	ctx->prepared = true;
+
+	return 0;
+
+disable_iovcc:
+	regulator_disable(ctx->iovcc);
+disable_vci:
+	regulator_disable(ctx->vci);
+	return ret;
+}
+
+static const struct drm_display_mode default_mode = {
+	.hdisplay	= 720,
+	.hsync_start	= 720 + 40,
+	.hsync_end	= 720 + 40 + 10,
+	.htotal		= 720 + 40 + 10 + 40,
+	.vdisplay	= 1280,
+	.vsync_start	= 1280 + 22,
+	.vsync_end	= 1280 + 22 + 4,
+	.vtotal		= 1280 + 22 + 4 + 11,
+	.vrefresh	= 60,
+	.clock		= 64000,
+	.width_mm	= 68,
+	.height_mm	= 121,
+};
+
+static int xpp055c272_get_modes(struct drm_panel *panel,
+				struct drm_connector *connector)
+{
+	struct xpp055c272 *ctx = panel_to_xpp055c272(panel);
+	struct drm_display_mode *mode;
+
+	mode = drm_mode_duplicate(connector->dev, &default_mode);
+	if (!mode) {
+		DRM_DEV_ERROR(ctx->dev, "Failed to add mode %ux%u@%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;
+	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 xpp055c272_funcs = {
+	.unprepare	= xpp055c272_unprepare,
+	.prepare	= xpp055c272_prepare,
+	.get_modes	= xpp055c272_get_modes,
+};
+
+static int xpp055c272_probe(struct mipi_dsi_device *dsi)
+{
+	struct device *dev = &dsi->dev;
+	struct xpp055c272 *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)) {
+		DRM_DEV_ERROR(dev, "cannot get reset gpio\n");
+		return PTR_ERR(ctx->reset_gpio);
+	}
+
+	ctx->vci = devm_regulator_get(dev, "vci");
+	if (IS_ERR(ctx->vci)) {
+		ret = PTR_ERR(ctx->vci);
+		if (ret != -EPROBE_DEFER)
+			DRM_DEV_ERROR(dev,
+				      "Failed to request vci regulator: %d\n",
+				      ret);
+		return ret;
+	}
+
+	ctx->iovcc = devm_regulator_get(dev, "iovcc");
+	if (IS_ERR(ctx->iovcc)) {
+		ret = PTR_ERR(ctx->iovcc);
+		if (ret != -EPROBE_DEFER)
+			DRM_DEV_ERROR(dev,
+				      "Failed to request iovcc regulator: %d\n",
+				      ret);
+		return ret;
+	}
+
+	mipi_dsi_set_drvdata(dsi, ctx);
+
+	ctx->dev = dev;
+
+	dsi->lanes = 4;
+	dsi->format = MIPI_DSI_FMT_RGB888;
+	dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
+			  MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_EOT_PACKET;
+
+	drm_panel_init(&ctx->panel, &dsi->dev, &xpp055c272_funcs,
+		       DRM_MODE_CONNECTOR_DSI);
+
+	ret = drm_panel_of_backlight(&ctx->panel);
+	if (ret)
+		return ret;
+
+	drm_panel_add(&ctx->panel);
+
+	ret = mipi_dsi_attach(dsi);
+	if (ret < 0) {
+		DRM_DEV_ERROR(dev, "mipi_dsi_attach failed: %d\n", ret);
+		drm_panel_remove(&ctx->panel);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void xpp055c272_shutdown(struct mipi_dsi_device *dsi)
+{
+	struct xpp055c272 *ctx = mipi_dsi_get_drvdata(dsi);
+	int ret;
+
+	ret = drm_panel_unprepare(&ctx->panel);
+	if (ret < 0)
+		DRM_DEV_ERROR(&dsi->dev, "Failed to unprepare panel: %d\n",
+			      ret);
+
+	ret = drm_panel_disable(&ctx->panel);
+	if (ret < 0)
+		DRM_DEV_ERROR(&dsi->dev, "Failed to disable panel: %d\n",
+			      ret);
+}
+
+static int xpp055c272_remove(struct mipi_dsi_device *dsi)
+{
+	struct xpp055c272 *ctx = mipi_dsi_get_drvdata(dsi);
+	int ret;
+
+	xpp055c272_shutdown(dsi);
+
+	ret = mipi_dsi_detach(dsi);
+	if (ret < 0)
+		DRM_DEV_ERROR(&dsi->dev, "Failed to detach from DSI host: %d\n",
+			      ret);
+
+	drm_panel_remove(&ctx->panel);
+
+	return 0;
+}
+
+static const struct of_device_id xpp055c272_of_match[] = {
+	{ .compatible = "xinpeng,xpp055c272" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, xpp055c272_of_match);
+
+static struct mipi_dsi_driver xpp055c272_driver = {
+	.driver = {
+		.name = "panel-xinpeng-xpp055c272",
+		.of_match_table = xpp055c272_of_match,
+	},
+	.probe	= xpp055c272_probe,
+	.remove = xpp055c272_remove,
+	.shutdown = xpp055c272_shutdown,
+};
+module_mipi_dsi_driver(xpp055c272_driver);
+
+MODULE_AUTHOR("Heiko Stuebner <heiko.stuebner@theobroma-systems.com>");
+MODULE_DESCRIPTION("DRM driver for Xinpeng xpp055c272 MIPI DSI panel");
+MODULE_LICENSE("GPL v2");