1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * AU Optronics A030JTN01.0 TFT LCD panel driver 4 * 5 * Copyright (C) 2023, Paul Cercueil <paul@crapouillou.net> 6 * Copyright (C) 2023, Christophe Branchereau <cbranchereau@gmail.com> 7 */ 8 9 #include <linux/bitfield.h> 10 #include <linux/delay.h> 11 #include <linux/device.h> 12 #include <linux/gpio/consumer.h> 13 #include <linux/media-bus-format.h> 14 #include <linux/mod_devicetable.h> 15 #include <linux/module.h> 16 #include <linux/regmap.h> 17 #include <linux/regulator/consumer.h> 18 #include <linux/spi/spi.h> 19 20 #include <drm/drm_modes.h> 21 #include <drm/drm_panel.h> 22 23 #define REG05 0x05 24 #define REG06 0x06 25 #define REG07 0x07 26 27 #define REG05_STDBY BIT(0) 28 #define REG06_VBLK GENMASK(4, 0) 29 #define REG07_HBLK GENMASK(7, 0) 30 31 32 struct a030jtn01_info { 33 const struct drm_display_mode *display_modes; 34 unsigned int num_modes; 35 u16 width_mm, height_mm; 36 u32 bus_format, bus_flags; 37 }; 38 39 struct a030jtn01 { 40 struct drm_panel panel; 41 struct spi_device *spi; 42 struct regmap *map; 43 44 const struct a030jtn01_info *panel_info; 45 46 struct regulator *supply; 47 struct gpio_desc *reset_gpio; 48 }; 49 50 static inline struct a030jtn01 *to_a030jtn01(struct drm_panel *panel) 51 { 52 return container_of(panel, struct a030jtn01, panel); 53 } 54 55 static int a030jtn01_prepare(struct drm_panel *panel) 56 { 57 struct a030jtn01 *priv = to_a030jtn01(panel); 58 struct device *dev = &priv->spi->dev; 59 unsigned int dummy; 60 int err; 61 62 err = regulator_enable(priv->supply); 63 if (err) { 64 dev_err(dev, "Failed to enable power supply: %d\n", err); 65 return err; 66 } 67 68 usleep_range(1000, 8000); 69 70 /* Reset the chip */ 71 gpiod_set_value_cansleep(priv->reset_gpio, 1); 72 usleep_range(100, 8000); 73 gpiod_set_value_cansleep(priv->reset_gpio, 0); 74 usleep_range(2000, 8000); 75 76 /* 77 * No idea why, but a register read (doesn't matter which) is needed to 78 * properly initialize the chip after a reset; otherwise, the colors 79 * will be wrong. It doesn't seem to be timing-related as a msleep(200) 80 * doesn't fix it. 81 */ 82 err = regmap_read(priv->map, REG05, &dummy); 83 if (err) 84 goto err_disable_regulator; 85 86 /* Use (24 + 6) == 0x1e as the vertical back porch */ 87 err = regmap_write(priv->map, REG06, FIELD_PREP(REG06_VBLK, 0x1e)); 88 if (err) 89 goto err_disable_regulator; 90 91 /* Use (42 + 30) * 3 == 0xd8 as the horizontal back porch */ 92 err = regmap_write(priv->map, REG07, FIELD_PREP(REG07_HBLK, 0xd8)); 93 if (err) 94 goto err_disable_regulator; 95 96 return 0; 97 98 err_disable_regulator: 99 gpiod_set_value_cansleep(priv->reset_gpio, 1); 100 regulator_disable(priv->supply); 101 return err; 102 } 103 104 static int a030jtn01_unprepare(struct drm_panel *panel) 105 { 106 struct a030jtn01 *priv = to_a030jtn01(panel); 107 108 gpiod_set_value_cansleep(priv->reset_gpio, 1); 109 regulator_disable(priv->supply); 110 111 return 0; 112 } 113 114 static int a030jtn01_enable(struct drm_panel *panel) 115 { 116 struct a030jtn01 *priv = to_a030jtn01(panel); 117 int ret; 118 119 ret = regmap_set_bits(priv->map, REG05, REG05_STDBY); 120 if (ret) 121 return ret; 122 123 /* Wait for the picture to be stable */ 124 if (panel->backlight) 125 msleep(100); 126 127 return 0; 128 } 129 130 static int a030jtn01_disable(struct drm_panel *panel) 131 { 132 struct a030jtn01 *priv = to_a030jtn01(panel); 133 134 return regmap_clear_bits(priv->map, REG05, REG05_STDBY); 135 } 136 137 static int a030jtn01_get_modes(struct drm_panel *panel, 138 struct drm_connector *connector) 139 { 140 struct a030jtn01 *priv = to_a030jtn01(panel); 141 const struct a030jtn01_info *panel_info = priv->panel_info; 142 struct drm_display_mode *mode; 143 unsigned int i; 144 145 for (i = 0; i < panel_info->num_modes; i++) { 146 mode = drm_mode_duplicate(connector->dev, 147 &panel_info->display_modes[i]); 148 if (!mode) 149 return -ENOMEM; 150 151 drm_mode_set_name(mode); 152 153 mode->type = DRM_MODE_TYPE_DRIVER; 154 if (panel_info->num_modes == 1) 155 mode->type |= DRM_MODE_TYPE_PREFERRED; 156 157 drm_mode_probed_add(connector, mode); 158 } 159 160 connector->display_info.bpc = 8; 161 connector->display_info.width_mm = panel_info->width_mm; 162 connector->display_info.height_mm = panel_info->height_mm; 163 164 drm_display_info_set_bus_formats(&connector->display_info, 165 &panel_info->bus_format, 1); 166 connector->display_info.bus_flags = panel_info->bus_flags; 167 168 return panel_info->num_modes; 169 } 170 171 static const struct drm_panel_funcs a030jtn01_funcs = { 172 .prepare = a030jtn01_prepare, 173 .unprepare = a030jtn01_unprepare, 174 .enable = a030jtn01_enable, 175 .disable = a030jtn01_disable, 176 .get_modes = a030jtn01_get_modes, 177 }; 178 179 static bool a030jtn01_has_reg(struct device *dev, unsigned int reg) 180 { 181 static const u32 a030jtn01_regs_mask = 0x001823f1fb; 182 183 return a030jtn01_regs_mask & BIT(reg); 184 }; 185 186 static const struct regmap_config a030jtn01_regmap_config = { 187 .reg_bits = 8, 188 .val_bits = 8, 189 .read_flag_mask = 0x40, 190 .max_register = 0x1c, 191 .readable_reg = a030jtn01_has_reg, 192 .writeable_reg = a030jtn01_has_reg, 193 }; 194 195 static int a030jtn01_probe(struct spi_device *spi) 196 { 197 struct device *dev = &spi->dev; 198 struct a030jtn01 *priv; 199 int err; 200 201 spi->mode |= SPI_MODE_3 | SPI_3WIRE; 202 203 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 204 if (!priv) 205 return -ENOMEM; 206 207 priv->spi = spi; 208 spi_set_drvdata(spi, priv); 209 210 priv->map = devm_regmap_init_spi(spi, &a030jtn01_regmap_config); 211 if (IS_ERR(priv->map)) 212 return dev_err_probe(dev, PTR_ERR(priv->map), "Unable to init regmap"); 213 214 priv->panel_info = spi_get_device_match_data(spi); 215 if (!priv->panel_info) 216 return -EINVAL; 217 218 priv->supply = devm_regulator_get(dev, "power"); 219 if (IS_ERR(priv->supply)) 220 return dev_err_probe(dev, PTR_ERR(priv->supply), "Failed to get power supply"); 221 222 priv->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); 223 if (IS_ERR(priv->reset_gpio)) 224 return dev_err_probe(dev, PTR_ERR(priv->reset_gpio), "Failed to get reset GPIO"); 225 226 drm_panel_init(&priv->panel, dev, &a030jtn01_funcs, 227 DRM_MODE_CONNECTOR_DPI); 228 229 err = drm_panel_of_backlight(&priv->panel); 230 if (err) 231 return err; 232 233 drm_panel_add(&priv->panel); 234 235 return 0; 236 } 237 238 static void a030jtn01_remove(struct spi_device *spi) 239 { 240 struct a030jtn01 *priv = spi_get_drvdata(spi); 241 242 drm_panel_remove(&priv->panel); 243 drm_panel_disable(&priv->panel); 244 drm_panel_unprepare(&priv->panel); 245 } 246 247 static const struct drm_display_mode a030jtn01_modes[] = { 248 { /* 60 Hz */ 249 .clock = 14400, 250 .hdisplay = 320, 251 .hsync_start = 320 + 8, 252 .hsync_end = 320 + 8 + 42, 253 .htotal = 320 + 8 + 42 + 30, 254 .vdisplay = 480, 255 .vsync_start = 480 + 90, 256 .vsync_end = 480 + 90 + 24, 257 .vtotal = 480 + 90 + 24 + 6, 258 .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC, 259 }, 260 { /* 50 Hz */ 261 .clock = 12000, 262 .hdisplay = 320, 263 .hsync_start = 320 + 8, 264 .hsync_end = 320 + 8 + 42, 265 .htotal = 320 + 8 + 42 + 30, 266 .vdisplay = 480, 267 .vsync_start = 480 + 90, 268 .vsync_end = 480 + 90 + 24, 269 .vtotal = 480 + 90 + 24 + 6, 270 .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC, 271 }, 272 }; 273 274 static const struct a030jtn01_info a030jtn01_info = { 275 .display_modes = a030jtn01_modes, 276 .num_modes = ARRAY_SIZE(a030jtn01_modes), 277 .width_mm = 70, 278 .height_mm = 51, 279 .bus_format = MEDIA_BUS_FMT_RGB888_3X8_DELTA, 280 .bus_flags = DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE, 281 }; 282 283 static const struct spi_device_id a030jtn01_id[] = { 284 { "a030jtn01", (kernel_ulong_t) &a030jtn01_info }, 285 { /* sentinel */ } 286 }; 287 MODULE_DEVICE_TABLE(spi, a030jtn01_id); 288 289 static const struct of_device_id a030jtn01_of_match[] = { 290 { .compatible = "auo,a030jtn01" }, 291 { /* sentinel */ } 292 }; 293 MODULE_DEVICE_TABLE(of, a030jtn01_of_match); 294 295 static struct spi_driver a030jtn01_driver = { 296 .driver = { 297 .name = "auo-a030jtn01", 298 .of_match_table = a030jtn01_of_match, 299 }, 300 .id_table = a030jtn01_id, 301 .probe = a030jtn01_probe, 302 .remove = a030jtn01_remove, 303 }; 304 module_spi_driver(a030jtn01_driver); 305 306 MODULE_AUTHOR("Paul Cercueil <paul@crapouillou.net>"); 307 MODULE_AUTHOR("Christophe Branchereau <cbranchereau@gmail.com>"); 308 MODULE_LICENSE("GPL"); 309