// SPDX-License-Identifier: GPL-2.0 /* * Novatek NT39016 TFT LCD panel driver * * Copyright (C) 2017, Maarten ter Huurne * Copyright (C) 2019, Paul Cercueil */ #include #include #include #include #include #include #include #include #include #include #include #include enum nt39016_regs { NT39016_REG_SYSTEM, NT39016_REG_TIMING, NT39016_REG_OP, NT39016_REG_DATA_IN, NT39016_REG_SRC_TIMING_DELAY, NT39016_REG_GATE_TIMING_DELAY, NT39016_REG_RESERVED, NT39016_REG_INITIAL_FUNC, NT39016_REG_CONTRAST, NT39016_REG_BRIGHTNESS, NT39016_REG_HUE_SATURATION, NT39016_REG_RB_SUBCONTRAST, NT39016_REG_R_SUBBRIGHTNESS, NT39016_REG_B_SUBBRIGHTNESS, NT39016_REG_VCOMDC, NT39016_REG_VCOMAC, NT39016_REG_VGAM2, NT39016_REG_VGAM34, NT39016_REG_VGAM56, NT39016_REG_VCOMDC_TRIM = 0x1e, NT39016_REG_DISPLAY_MODE = 0x20, }; #define NT39016_SYSTEM_RESET_N BIT(0) #define NT39016_SYSTEM_STANDBY BIT(1) struct nt39016_panel_info { const struct drm_display_mode *display_modes; unsigned int num_modes; u16 width_mm, height_mm; u32 bus_format, bus_flags; }; struct nt39016 { struct drm_panel drm_panel; struct regmap *map; struct regulator *supply; const struct nt39016_panel_info *panel_info; struct gpio_desc *reset_gpio; }; static inline struct nt39016 *to_nt39016(struct drm_panel *panel) { return container_of(panel, struct nt39016, drm_panel); } #define RV(REG, VAL) { .reg = (REG), .def = (VAL), .delay_us = 2 } static const struct reg_sequence nt39016_panel_regs[] = { RV(NT39016_REG_SYSTEM, 0x00), RV(NT39016_REG_TIMING, 0x00), RV(NT39016_REG_OP, 0x03), RV(NT39016_REG_DATA_IN, 0xCC), RV(NT39016_REG_SRC_TIMING_DELAY, 0x46), RV(NT39016_REG_GATE_TIMING_DELAY, 0x05), RV(NT39016_REG_RESERVED, 0x00), RV(NT39016_REG_INITIAL_FUNC, 0x00), RV(NT39016_REG_CONTRAST, 0x08), RV(NT39016_REG_BRIGHTNESS, 0x40), RV(NT39016_REG_HUE_SATURATION, 0x88), RV(NT39016_REG_RB_SUBCONTRAST, 0x88), RV(NT39016_REG_R_SUBBRIGHTNESS, 0x20), RV(NT39016_REG_B_SUBBRIGHTNESS, 0x20), RV(NT39016_REG_VCOMDC, 0x67), RV(NT39016_REG_VCOMAC, 0xA4), RV(NT39016_REG_VGAM2, 0x04), RV(NT39016_REG_VGAM34, 0x24), RV(NT39016_REG_VGAM56, 0x24), RV(NT39016_REG_DISPLAY_MODE, 0x00), }; #undef RV static const struct regmap_range nt39016_regmap_no_ranges[] = { regmap_reg_range(0x13, 0x1D), regmap_reg_range(0x1F, 0x1F), }; static const struct regmap_access_table nt39016_regmap_access_table = { .no_ranges = nt39016_regmap_no_ranges, .n_no_ranges = ARRAY_SIZE(nt39016_regmap_no_ranges), }; static const struct regmap_config nt39016_regmap_config = { .reg_bits = 6, .pad_bits = 2, .val_bits = 8, .max_register = NT39016_REG_DISPLAY_MODE, .wr_table = &nt39016_regmap_access_table, .write_flag_mask = 0x02, .cache_type = REGCACHE_FLAT, }; static int nt39016_prepare(struct drm_panel *drm_panel) { struct nt39016 *panel = to_nt39016(drm_panel); int err; err = regulator_enable(panel->supply); if (err) { dev_err(drm_panel->dev, "Failed to enable power supply: %d\n", err); return err; } /* * Reset the NT39016. * The documentation says the reset pulse should be at least 40 us to * pass the glitch filter, but when testing I see some resets fail and * some succeed when using a 70 us delay, so we use 100 us instead. */ gpiod_set_value_cansleep(panel->reset_gpio, 1); usleep_range(100, 1000); gpiod_set_value_cansleep(panel->reset_gpio, 0); udelay(2); /* Init all registers. */ err = regmap_multi_reg_write(panel->map, nt39016_panel_regs, ARRAY_SIZE(nt39016_panel_regs)); if (err) { dev_err(drm_panel->dev, "Failed to init registers: %d\n", err); goto err_disable_regulator; } return 0; err_disable_regulator: regulator_disable(panel->supply); return err; } static int nt39016_unprepare(struct drm_panel *drm_panel) { struct nt39016 *panel = to_nt39016(drm_panel); gpiod_set_value_cansleep(panel->reset_gpio, 1); regulator_disable(panel->supply); return 0; } static int nt39016_enable(struct drm_panel *drm_panel) { struct nt39016 *panel = to_nt39016(drm_panel); int ret; ret = regmap_write(panel->map, NT39016_REG_SYSTEM, NT39016_SYSTEM_RESET_N | NT39016_SYSTEM_STANDBY); if (ret) { dev_err(drm_panel->dev, "Unable to enable panel: %d\n", ret); return ret; } if (drm_panel->backlight) { /* Wait for the picture to be ready before enabling backlight */ msleep(150); } return 0; } static int nt39016_disable(struct drm_panel *drm_panel) { struct nt39016 *panel = to_nt39016(drm_panel); int err; err = regmap_write(panel->map, NT39016_REG_SYSTEM, NT39016_SYSTEM_RESET_N); if (err) { dev_err(drm_panel->dev, "Unable to disable panel: %d\n", err); return err; } return 0; } static int nt39016_get_modes(struct drm_panel *drm_panel, struct drm_connector *connector) { struct nt39016 *panel = to_nt39016(drm_panel); const struct nt39016_panel_info *panel_info = panel->panel_info; struct drm_display_mode *mode; unsigned int i; for (i = 0; i < panel_info->num_modes; i++) { mode = drm_mode_duplicate(connector->dev, &panel_info->display_modes[i]); if (!mode) return -ENOMEM; drm_mode_set_name(mode); mode->type = DRM_MODE_TYPE_DRIVER; if (panel_info->num_modes == 1) mode->type |= DRM_MODE_TYPE_PREFERRED; drm_mode_probed_add(connector, mode); } connector->display_info.bpc = 8; connector->display_info.width_mm = panel_info->width_mm; connector->display_info.height_mm = panel_info->height_mm; drm_display_info_set_bus_formats(&connector->display_info, &panel_info->bus_format, 1); connector->display_info.bus_flags = panel_info->bus_flags; return panel_info->num_modes; } static const struct drm_panel_funcs nt39016_funcs = { .prepare = nt39016_prepare, .unprepare = nt39016_unprepare, .enable = nt39016_enable, .disable = nt39016_disable, .get_modes = nt39016_get_modes, }; static int nt39016_probe(struct spi_device *spi) { struct device *dev = &spi->dev; struct nt39016 *panel; int err; panel = devm_kzalloc(dev, sizeof(*panel), GFP_KERNEL); if (!panel) return -ENOMEM; spi_set_drvdata(spi, panel); panel->panel_info = of_device_get_match_data(dev); if (!panel->panel_info) return -EINVAL; panel->supply = devm_regulator_get(dev, "power"); if (IS_ERR(panel->supply)) { dev_err(dev, "Failed to get power supply\n"); return PTR_ERR(panel->supply); } panel->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); if (IS_ERR(panel->reset_gpio)) { dev_err(dev, "Failed to get reset GPIO\n"); return PTR_ERR(panel->reset_gpio); } spi->bits_per_word = 8; spi->mode = SPI_MODE_3 | SPI_3WIRE; err = spi_setup(spi); if (err) { dev_err(dev, "Failed to setup SPI\n"); return err; } panel->map = devm_regmap_init_spi(spi, &nt39016_regmap_config); if (IS_ERR(panel->map)) { dev_err(dev, "Failed to init regmap\n"); return PTR_ERR(panel->map); } drm_panel_init(&panel->drm_panel, dev, &nt39016_funcs, DRM_MODE_CONNECTOR_DPI); err = drm_panel_of_backlight(&panel->drm_panel); if (err) { if (err != -EPROBE_DEFER) dev_err(dev, "Failed to get backlight handle\n"); return err; } drm_panel_add(&panel->drm_panel); return 0; } static int nt39016_remove(struct spi_device *spi) { struct nt39016 *panel = spi_get_drvdata(spi); drm_panel_remove(&panel->drm_panel); nt39016_disable(&panel->drm_panel); nt39016_unprepare(&panel->drm_panel); return 0; } static const struct drm_display_mode kd035g6_display_modes[] = { { /* 60 Hz */ .clock = 6000, .hdisplay = 320, .hsync_start = 320 + 10, .hsync_end = 320 + 10 + 50, .htotal = 320 + 10 + 50 + 20, .vdisplay = 240, .vsync_start = 240 + 5, .vsync_end = 240 + 5 + 1, .vtotal = 240 + 5 + 1 + 4, .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC, }, { /* 50 Hz */ .clock = 5400, .hdisplay = 320, .hsync_start = 320 + 42, .hsync_end = 320 + 42 + 50, .htotal = 320 + 42 + 50 + 20, .vdisplay = 240, .vsync_start = 240 + 5, .vsync_end = 240 + 5 + 1, .vtotal = 240 + 5 + 1 + 4, .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC, }, }; static const struct nt39016_panel_info kd035g6_info = { .display_modes = kd035g6_display_modes, .num_modes = ARRAY_SIZE(kd035g6_display_modes), .width_mm = 71, .height_mm = 53, .bus_format = MEDIA_BUS_FMT_RGB888_1X24, .bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE, }; static const struct of_device_id nt39016_of_match[] = { { .compatible = "kingdisplay,kd035g6-54nt", .data = &kd035g6_info }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, nt39016_of_match); static struct spi_driver nt39016_driver = { .driver = { .name = "nt39016", .of_match_table = nt39016_of_match, }, .probe = nt39016_probe, .remove = nt39016_remove, }; module_spi_driver(nt39016_driver); MODULE_AUTHOR("Maarten ter Huurne "); MODULE_AUTHOR("Paul Cercueil "); MODULE_LICENSE("GPL v2");