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1// SPDX-License-Identifier: GPL-2.02/*3 * Novatek NT39016 TFT LCD panel driver4 *5 * Copyright (C) 2017, Maarten ter Huurne <maarten@treewalker.org>6 * Copyright (C) 2019, Paul Cercueil <paul@crapouillou.net>7 */8 9#include <linux/delay.h>10#include <linux/device.h>11#include <linux/gpio/consumer.h>12#include <linux/media-bus-format.h>13#include <linux/module.h>14#include <linux/of.h>15#include <linux/regmap.h>16#include <linux/regulator/consumer.h>17#include <linux/spi/spi.h>18 19#include <drm/drm_modes.h>20#include <drm/drm_panel.h>21 22enum nt39016_regs {23 NT39016_REG_SYSTEM,24 NT39016_REG_TIMING,25 NT39016_REG_OP,26 NT39016_REG_DATA_IN,27 NT39016_REG_SRC_TIMING_DELAY,28 NT39016_REG_GATE_TIMING_DELAY,29 NT39016_REG_RESERVED,30 NT39016_REG_INITIAL_FUNC,31 NT39016_REG_CONTRAST,32 NT39016_REG_BRIGHTNESS,33 NT39016_REG_HUE_SATURATION,34 NT39016_REG_RB_SUBCONTRAST,35 NT39016_REG_R_SUBBRIGHTNESS,36 NT39016_REG_B_SUBBRIGHTNESS,37 NT39016_REG_VCOMDC,38 NT39016_REG_VCOMAC,39 NT39016_REG_VGAM2,40 NT39016_REG_VGAM34,41 NT39016_REG_VGAM56,42 NT39016_REG_VCOMDC_TRIM = 0x1e,43 NT39016_REG_DISPLAY_MODE = 0x20,44};45 46#define NT39016_SYSTEM_RESET_N BIT(0)47#define NT39016_SYSTEM_STANDBY BIT(1)48 49struct nt39016_panel_info {50 const struct drm_display_mode *display_modes;51 unsigned int num_modes;52 u16 width_mm, height_mm;53 u32 bus_format, bus_flags;54};55 56struct nt39016 {57 struct drm_panel drm_panel;58 struct regmap *map;59 struct regulator *supply;60 const struct nt39016_panel_info *panel_info;61 62 struct gpio_desc *reset_gpio;63};64 65static inline struct nt39016 *to_nt39016(struct drm_panel *panel)66{67 return container_of(panel, struct nt39016, drm_panel);68}69 70#define RV(REG, VAL) { .reg = (REG), .def = (VAL), .delay_us = 2 }71static const struct reg_sequence nt39016_panel_regs[] = {72 RV(NT39016_REG_SYSTEM, 0x00),73 RV(NT39016_REG_TIMING, 0x00),74 RV(NT39016_REG_OP, 0x03),75 RV(NT39016_REG_DATA_IN, 0xCC),76 RV(NT39016_REG_SRC_TIMING_DELAY, 0x46),77 RV(NT39016_REG_GATE_TIMING_DELAY, 0x05),78 RV(NT39016_REG_RESERVED, 0x00),79 RV(NT39016_REG_INITIAL_FUNC, 0x00),80 RV(NT39016_REG_CONTRAST, 0x08),81 RV(NT39016_REG_BRIGHTNESS, 0x40),82 RV(NT39016_REG_HUE_SATURATION, 0x88),83 RV(NT39016_REG_RB_SUBCONTRAST, 0x88),84 RV(NT39016_REG_R_SUBBRIGHTNESS, 0x20),85 RV(NT39016_REG_B_SUBBRIGHTNESS, 0x20),86 RV(NT39016_REG_VCOMDC, 0x67),87 RV(NT39016_REG_VCOMAC, 0xA4),88 RV(NT39016_REG_VGAM2, 0x04),89 RV(NT39016_REG_VGAM34, 0x24),90 RV(NT39016_REG_VGAM56, 0x24),91 RV(NT39016_REG_DISPLAY_MODE, 0x00),92};93 94#undef RV95 96static const struct regmap_range nt39016_regmap_no_ranges[] = {97 regmap_reg_range(0x13, 0x1D),98 regmap_reg_range(0x1F, 0x1F),99};100 101static const struct regmap_access_table nt39016_regmap_access_table = {102 .no_ranges = nt39016_regmap_no_ranges,103 .n_no_ranges = ARRAY_SIZE(nt39016_regmap_no_ranges),104};105 106static const struct regmap_config nt39016_regmap_config = {107 .reg_bits = 6,108 .pad_bits = 2,109 .val_bits = 8,110 111 .max_register = NT39016_REG_DISPLAY_MODE,112 .wr_table = &nt39016_regmap_access_table,113 .write_flag_mask = 0x02,114 115 .cache_type = REGCACHE_FLAT,116};117 118static int nt39016_prepare(struct drm_panel *drm_panel)119{120 struct nt39016 *panel = to_nt39016(drm_panel);121 int err;122 123 err = regulator_enable(panel->supply);124 if (err) {125 dev_err(drm_panel->dev, "Failed to enable power supply: %d\n", err);126 return err;127 }128 129 /*130 * Reset the NT39016.131 * The documentation says the reset pulse should be at least 40 us to132 * pass the glitch filter, but when testing I see some resets fail and133 * some succeed when using a 70 us delay, so we use 100 us instead.134 */135 gpiod_set_value_cansleep(panel->reset_gpio, 1);136 usleep_range(100, 1000);137 gpiod_set_value_cansleep(panel->reset_gpio, 0);138 udelay(2);139 140 /* Init all registers. */141 err = regmap_multi_reg_write(panel->map, nt39016_panel_regs,142 ARRAY_SIZE(nt39016_panel_regs));143 if (err) {144 dev_err(drm_panel->dev, "Failed to init registers: %d\n", err);145 goto err_disable_regulator;146 }147 148 return 0;149 150err_disable_regulator:151 regulator_disable(panel->supply);152 return err;153}154 155static int nt39016_unprepare(struct drm_panel *drm_panel)156{157 struct nt39016 *panel = to_nt39016(drm_panel);158 159 gpiod_set_value_cansleep(panel->reset_gpio, 1);160 161 regulator_disable(panel->supply);162 163 return 0;164}165 166static int nt39016_enable(struct drm_panel *drm_panel)167{168 struct nt39016 *panel = to_nt39016(drm_panel);169 int ret;170 171 ret = regmap_write(panel->map, NT39016_REG_SYSTEM,172 NT39016_SYSTEM_RESET_N | NT39016_SYSTEM_STANDBY);173 if (ret) {174 dev_err(drm_panel->dev, "Unable to enable panel: %d\n", ret);175 return ret;176 }177 178 if (drm_panel->backlight) {179 /* Wait for the picture to be ready before enabling backlight */180 msleep(150);181 }182 183 return 0;184}185 186static int nt39016_disable(struct drm_panel *drm_panel)187{188 struct nt39016 *panel = to_nt39016(drm_panel);189 int err;190 191 err = regmap_write(panel->map, NT39016_REG_SYSTEM,192 NT39016_SYSTEM_RESET_N);193 if (err) {194 dev_err(drm_panel->dev, "Unable to disable panel: %d\n", err);195 return err;196 }197 198 return 0;199}200 201static int nt39016_get_modes(struct drm_panel *drm_panel,202 struct drm_connector *connector)203{204 struct nt39016 *panel = to_nt39016(drm_panel);205 const struct nt39016_panel_info *panel_info = panel->panel_info;206 struct drm_display_mode *mode;207 unsigned int i;208 209 for (i = 0; i < panel_info->num_modes; i++) {210 mode = drm_mode_duplicate(connector->dev,211 &panel_info->display_modes[i]);212 if (!mode)213 return -ENOMEM;214 215 drm_mode_set_name(mode);216 217 mode->type = DRM_MODE_TYPE_DRIVER;218 if (panel_info->num_modes == 1)219 mode->type |= DRM_MODE_TYPE_PREFERRED;220 221 drm_mode_probed_add(connector, mode);222 }223 224 connector->display_info.bpc = 8;225 connector->display_info.width_mm = panel_info->width_mm;226 connector->display_info.height_mm = panel_info->height_mm;227 228 drm_display_info_set_bus_formats(&connector->display_info,229 &panel_info->bus_format, 1);230 connector->display_info.bus_flags = panel_info->bus_flags;231 232 return panel_info->num_modes;233}234 235static const struct drm_panel_funcs nt39016_funcs = {236 .prepare = nt39016_prepare,237 .unprepare = nt39016_unprepare,238 .enable = nt39016_enable,239 .disable = nt39016_disable,240 .get_modes = nt39016_get_modes,241};242 243static int nt39016_probe(struct spi_device *spi)244{245 struct device *dev = &spi->dev;246 struct nt39016 *panel;247 int err;248 249 panel = devm_kzalloc(dev, sizeof(*panel), GFP_KERNEL);250 if (!panel)251 return -ENOMEM;252 253 spi_set_drvdata(spi, panel);254 255 panel->panel_info = of_device_get_match_data(dev);256 if (!panel->panel_info)257 return -EINVAL;258 259 panel->supply = devm_regulator_get(dev, "power");260 if (IS_ERR(panel->supply))261 return dev_err_probe(dev, PTR_ERR(panel->supply),262 "Failed to get power supply\n");263 264 panel->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);265 if (IS_ERR(panel->reset_gpio))266 return dev_err_probe(dev, PTR_ERR(panel->reset_gpio), "Failed to get reset GPIO\n");267 268 spi->bits_per_word = 8;269 spi->mode = SPI_MODE_3 | SPI_3WIRE;270 err = spi_setup(spi);271 if (err) {272 dev_err(dev, "Failed to setup SPI\n");273 return err;274 }275 276 panel->map = devm_regmap_init_spi(spi, &nt39016_regmap_config);277 if (IS_ERR(panel->map)) {278 dev_err(dev, "Failed to init regmap\n");279 return PTR_ERR(panel->map);280 }281 282 drm_panel_init(&panel->drm_panel, dev, &nt39016_funcs,283 DRM_MODE_CONNECTOR_DPI);284 285 err = drm_panel_of_backlight(&panel->drm_panel);286 if (err)287 return dev_err_probe(dev, err, "Failed to get backlight handle\n");288 289 drm_panel_add(&panel->drm_panel);290 291 return 0;292}293 294static void nt39016_remove(struct spi_device *spi)295{296 struct nt39016 *panel = spi_get_drvdata(spi);297 298 drm_panel_remove(&panel->drm_panel);299 300 nt39016_disable(&panel->drm_panel);301 nt39016_unprepare(&panel->drm_panel);302}303 304static const struct drm_display_mode kd035g6_display_modes[] = {305 { /* 60 Hz */306 .clock = 6000,307 .hdisplay = 320,308 .hsync_start = 320 + 10,309 .hsync_end = 320 + 10 + 50,310 .htotal = 320 + 10 + 50 + 20,311 .vdisplay = 240,312 .vsync_start = 240 + 5,313 .vsync_end = 240 + 5 + 1,314 .vtotal = 240 + 5 + 1 + 4,315 .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,316 },317 { /* 50 Hz */318 .clock = 5400,319 .hdisplay = 320,320 .hsync_start = 320 + 42,321 .hsync_end = 320 + 42 + 50,322 .htotal = 320 + 42 + 50 + 20,323 .vdisplay = 240,324 .vsync_start = 240 + 5,325 .vsync_end = 240 + 5 + 1,326 .vtotal = 240 + 5 + 1 + 4,327 .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,328 },329};330 331static const struct nt39016_panel_info kd035g6_info = {332 .display_modes = kd035g6_display_modes,333 .num_modes = ARRAY_SIZE(kd035g6_display_modes),334 .width_mm = 71,335 .height_mm = 53,336 .bus_format = MEDIA_BUS_FMT_RGB888_1X24,337 .bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,338};339 340static const struct of_device_id nt39016_of_match[] = {341 { .compatible = "kingdisplay,kd035g6-54nt", .data = &kd035g6_info },342 { /* sentinel */ }343};344MODULE_DEVICE_TABLE(of, nt39016_of_match);345 346static struct spi_driver nt39016_driver = {347 .driver = {348 .name = "nt39016",349 .of_match_table = nt39016_of_match,350 },351 .probe = nt39016_probe,352 .remove = nt39016_remove,353};354 355module_spi_driver(nt39016_driver);356 357MODULE_AUTHOR("Maarten ter Huurne <maarten@treewalker.org>");358MODULE_AUTHOR("Paul Cercueil <paul@crapouillou.net>");359MODULE_DESCRIPTION("Novatek NT39016 TFT LCD panel driver");360MODULE_LICENSE("GPL v2");361