1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Toppoly TD043MTEA1 Panel Driver 4 * 5 * Copyright (C) 2019 Texas Instruments Incorporated 6 * 7 * Based on the omapdrm-specific panel-tpo-td043mtea1 driver 8 * 9 * Author: Gražvydas Ignotas <notasas@gmail.com> 10 */ 11 12 #include <linux/delay.h> 13 #include <linux/module.h> 14 #include <linux/regulator/consumer.h> 15 #include <linux/spi/spi.h> 16 17 #include <drm/drm_connector.h> 18 #include <drm/drm_modes.h> 19 #include <drm/drm_panel.h> 20 21 #define TPO_R02_MODE(x) ((x) & 7) 22 #define TPO_R02_MODE_800x480 7 23 #define TPO_R02_NCLK_RISING BIT(3) 24 #define TPO_R02_HSYNC_HIGH BIT(4) 25 #define TPO_R02_VSYNC_HIGH BIT(5) 26 27 #define TPO_R03_NSTANDBY BIT(0) 28 #define TPO_R03_EN_CP_CLK BIT(1) 29 #define TPO_R03_EN_VGL_PUMP BIT(2) 30 #define TPO_R03_EN_PWM BIT(3) 31 #define TPO_R03_DRIVING_CAP_100 BIT(4) 32 #define TPO_R03_EN_PRE_CHARGE BIT(6) 33 #define TPO_R03_SOFTWARE_CTL BIT(7) 34 35 #define TPO_R04_NFLIP_H BIT(0) 36 #define TPO_R04_NFLIP_V BIT(1) 37 #define TPO_R04_CP_CLK_FREQ_1H BIT(2) 38 #define TPO_R04_VGL_FREQ_1H BIT(4) 39 40 #define TPO_R03_VAL_NORMAL \ 41 (TPO_R03_NSTANDBY | TPO_R03_EN_CP_CLK | TPO_R03_EN_VGL_PUMP | \ 42 TPO_R03_EN_PWM | TPO_R03_DRIVING_CAP_100 | TPO_R03_EN_PRE_CHARGE | \ 43 TPO_R03_SOFTWARE_CTL) 44 45 #define TPO_R03_VAL_STANDBY \ 46 (TPO_R03_DRIVING_CAP_100 | TPO_R03_EN_PRE_CHARGE | \ 47 TPO_R03_SOFTWARE_CTL) 48 49 static const u16 td043mtea1_def_gamma[12] = { 50 105, 315, 381, 431, 490, 537, 579, 686, 780, 837, 880, 1023 51 }; 52 53 struct td043mtea1_panel { 54 struct drm_panel panel; 55 56 struct spi_device *spi; 57 struct regulator *vcc_reg; 58 struct gpio_desc *reset_gpio; 59 60 unsigned int mode; 61 u16 gamma[12]; 62 bool vmirror; 63 bool powered_on; 64 bool spi_suspended; 65 bool power_on_resume; 66 }; 67 68 #define to_td043mtea1_device(p) container_of(p, struct td043mtea1_panel, panel) 69 70 /* ----------------------------------------------------------------------------- 71 * Hardware Access 72 */ 73 74 static int td043mtea1_write(struct td043mtea1_panel *lcd, u8 addr, u8 value) 75 { 76 struct spi_message msg; 77 struct spi_transfer xfer; 78 u16 data; 79 int ret; 80 81 spi_message_init(&msg); 82 83 memset(&xfer, 0, sizeof(xfer)); 84 85 data = ((u16)addr << 10) | (1 << 8) | value; 86 xfer.tx_buf = &data; 87 xfer.bits_per_word = 16; 88 xfer.len = 2; 89 spi_message_add_tail(&xfer, &msg); 90 91 ret = spi_sync(lcd->spi, &msg); 92 if (ret < 0) 93 dev_warn(&lcd->spi->dev, "failed to write to LCD reg (%d)\n", 94 ret); 95 96 return ret; 97 } 98 99 static void td043mtea1_write_gamma(struct td043mtea1_panel *lcd) 100 { 101 const u16 *gamma = lcd->gamma; 102 unsigned int i; 103 u8 val; 104 105 /* gamma bits [9:8] */ 106 for (val = i = 0; i < 4; i++) 107 val |= (gamma[i] & 0x300) >> ((i + 1) * 2); 108 td043mtea1_write(lcd, 0x11, val); 109 110 for (val = i = 0; i < 4; i++) 111 val |= (gamma[i + 4] & 0x300) >> ((i + 1) * 2); 112 td043mtea1_write(lcd, 0x12, val); 113 114 for (val = i = 0; i < 4; i++) 115 val |= (gamma[i + 8] & 0x300) >> ((i + 1) * 2); 116 td043mtea1_write(lcd, 0x13, val); 117 118 /* gamma bits [7:0] */ 119 for (i = 0; i < 12; i++) 120 td043mtea1_write(lcd, 0x14 + i, gamma[i] & 0xff); 121 } 122 123 static int td043mtea1_write_mirror(struct td043mtea1_panel *lcd) 124 { 125 u8 reg4 = TPO_R04_NFLIP_H | TPO_R04_NFLIP_V | 126 TPO_R04_CP_CLK_FREQ_1H | TPO_R04_VGL_FREQ_1H; 127 if (lcd->vmirror) 128 reg4 &= ~TPO_R04_NFLIP_V; 129 130 return td043mtea1_write(lcd, 4, reg4); 131 } 132 133 static int td043mtea1_power_on(struct td043mtea1_panel *lcd) 134 { 135 int ret; 136 137 if (lcd->powered_on) 138 return 0; 139 140 ret = regulator_enable(lcd->vcc_reg); 141 if (ret < 0) 142 return ret; 143 144 /* Wait for the panel to stabilize. */ 145 msleep(160); 146 147 gpiod_set_value(lcd->reset_gpio, 0); 148 149 td043mtea1_write(lcd, 2, TPO_R02_MODE(lcd->mode) | TPO_R02_NCLK_RISING); 150 td043mtea1_write(lcd, 3, TPO_R03_VAL_NORMAL); 151 td043mtea1_write(lcd, 0x20, 0xf0); 152 td043mtea1_write(lcd, 0x21, 0xf0); 153 td043mtea1_write_mirror(lcd); 154 td043mtea1_write_gamma(lcd); 155 156 lcd->powered_on = true; 157 158 return 0; 159 } 160 161 static void td043mtea1_power_off(struct td043mtea1_panel *lcd) 162 { 163 if (!lcd->powered_on) 164 return; 165 166 td043mtea1_write(lcd, 3, TPO_R03_VAL_STANDBY | TPO_R03_EN_PWM); 167 168 gpiod_set_value(lcd->reset_gpio, 1); 169 170 /* wait for at least 2 vsyncs before cutting off power */ 171 msleep(50); 172 173 td043mtea1_write(lcd, 3, TPO_R03_VAL_STANDBY); 174 175 regulator_disable(lcd->vcc_reg); 176 177 lcd->powered_on = false; 178 } 179 180 /* ----------------------------------------------------------------------------- 181 * sysfs 182 */ 183 184 static ssize_t vmirror_show(struct device *dev, struct device_attribute *attr, 185 char *buf) 186 { 187 struct td043mtea1_panel *lcd = dev_get_drvdata(dev); 188 189 return snprintf(buf, PAGE_SIZE, "%d\n", lcd->vmirror); 190 } 191 192 static ssize_t vmirror_store(struct device *dev, struct device_attribute *attr, 193 const char *buf, size_t count) 194 { 195 struct td043mtea1_panel *lcd = dev_get_drvdata(dev); 196 int val; 197 int ret; 198 199 ret = kstrtoint(buf, 0, &val); 200 if (ret < 0) 201 return ret; 202 203 lcd->vmirror = !!val; 204 205 ret = td043mtea1_write_mirror(lcd); 206 if (ret < 0) 207 return ret; 208 209 return count; 210 } 211 212 static ssize_t mode_show(struct device *dev, struct device_attribute *attr, 213 char *buf) 214 { 215 struct td043mtea1_panel *lcd = dev_get_drvdata(dev); 216 217 return snprintf(buf, PAGE_SIZE, "%d\n", lcd->mode); 218 } 219 220 static ssize_t mode_store(struct device *dev, struct device_attribute *attr, 221 const char *buf, size_t count) 222 { 223 struct td043mtea1_panel *lcd = dev_get_drvdata(dev); 224 long val; 225 int ret; 226 227 ret = kstrtol(buf, 0, &val); 228 if (ret != 0 || val & ~7) 229 return -EINVAL; 230 231 lcd->mode = val; 232 233 val |= TPO_R02_NCLK_RISING; 234 td043mtea1_write(lcd, 2, val); 235 236 return count; 237 } 238 239 static ssize_t gamma_show(struct device *dev, struct device_attribute *attr, 240 char *buf) 241 { 242 struct td043mtea1_panel *lcd = dev_get_drvdata(dev); 243 ssize_t len = 0; 244 unsigned int i; 245 int ret; 246 247 for (i = 0; i < ARRAY_SIZE(lcd->gamma); i++) { 248 ret = snprintf(buf + len, PAGE_SIZE - len, "%u ", 249 lcd->gamma[i]); 250 if (ret < 0) 251 return ret; 252 len += ret; 253 } 254 buf[len - 1] = '\n'; 255 256 return len; 257 } 258 259 static ssize_t gamma_store(struct device *dev, struct device_attribute *attr, 260 const char *buf, size_t count) 261 { 262 struct td043mtea1_panel *lcd = dev_get_drvdata(dev); 263 unsigned int g[12]; 264 unsigned int i; 265 int ret; 266 267 ret = sscanf(buf, "%u %u %u %u %u %u %u %u %u %u %u %u", 268 &g[0], &g[1], &g[2], &g[3], &g[4], &g[5], 269 &g[6], &g[7], &g[8], &g[9], &g[10], &g[11]); 270 if (ret != 12) 271 return -EINVAL; 272 273 for (i = 0; i < 12; i++) 274 lcd->gamma[i] = g[i]; 275 276 td043mtea1_write_gamma(lcd); 277 278 return count; 279 } 280 281 static DEVICE_ATTR_RW(vmirror); 282 static DEVICE_ATTR_RW(mode); 283 static DEVICE_ATTR_RW(gamma); 284 285 static struct attribute *td043mtea1_attrs[] = { 286 &dev_attr_vmirror.attr, 287 &dev_attr_mode.attr, 288 &dev_attr_gamma.attr, 289 NULL, 290 }; 291 292 static const struct attribute_group td043mtea1_attr_group = { 293 .attrs = td043mtea1_attrs, 294 }; 295 296 /* ----------------------------------------------------------------------------- 297 * Panel Operations 298 */ 299 300 static int td043mtea1_unprepare(struct drm_panel *panel) 301 { 302 struct td043mtea1_panel *lcd = to_td043mtea1_device(panel); 303 304 if (!lcd->spi_suspended) 305 td043mtea1_power_off(lcd); 306 307 return 0; 308 } 309 310 static int td043mtea1_prepare(struct drm_panel *panel) 311 { 312 struct td043mtea1_panel *lcd = to_td043mtea1_device(panel); 313 int ret; 314 315 /* 316 * If we are resuming from system suspend, SPI might not be enabled 317 * yet, so we'll program the LCD from SPI PM resume callback. 318 */ 319 if (lcd->spi_suspended) 320 return 0; 321 322 ret = td043mtea1_power_on(lcd); 323 if (ret) { 324 dev_err(&lcd->spi->dev, "%s: power on failed (%d)\n", 325 __func__, ret); 326 return ret; 327 } 328 329 return 0; 330 } 331 332 static const struct drm_display_mode td043mtea1_mode = { 333 .clock = 36000, 334 .hdisplay = 800, 335 .hsync_start = 800 + 68, 336 .hsync_end = 800 + 68 + 1, 337 .htotal = 800 + 68 + 1 + 214, 338 .vdisplay = 480, 339 .vsync_start = 480 + 39, 340 .vsync_end = 480 + 39 + 1, 341 .vtotal = 480 + 39 + 1 + 34, 342 .type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED, 343 .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC, 344 .width_mm = 94, 345 .height_mm = 56, 346 }; 347 348 static int td043mtea1_get_modes(struct drm_panel *panel, 349 struct drm_connector *connector) 350 { 351 struct drm_display_mode *mode; 352 353 mode = drm_mode_duplicate(connector->dev, &td043mtea1_mode); 354 if (!mode) 355 return -ENOMEM; 356 357 drm_mode_set_name(mode); 358 drm_mode_probed_add(connector, mode); 359 360 connector->display_info.width_mm = td043mtea1_mode.width_mm; 361 connector->display_info.height_mm = td043mtea1_mode.height_mm; 362 /* 363 * FIXME: According to the datasheet sync signals are sampled on the 364 * rising edge of the clock, but the code running on the OMAP3 Pandora 365 * indicates sampling on the falling edge. This should be tested on a 366 * real device. 367 */ 368 connector->display_info.bus_flags = DRM_BUS_FLAG_DE_HIGH 369 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE 370 | DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE; 371 372 return 1; 373 } 374 375 static const struct drm_panel_funcs td043mtea1_funcs = { 376 .unprepare = td043mtea1_unprepare, 377 .prepare = td043mtea1_prepare, 378 .get_modes = td043mtea1_get_modes, 379 }; 380 381 /* ----------------------------------------------------------------------------- 382 * Power Management, Probe and Remove 383 */ 384 385 static int __maybe_unused td043mtea1_suspend(struct device *dev) 386 { 387 struct td043mtea1_panel *lcd = dev_get_drvdata(dev); 388 389 if (lcd->powered_on) { 390 td043mtea1_power_off(lcd); 391 lcd->powered_on = true; 392 } 393 394 lcd->spi_suspended = true; 395 396 return 0; 397 } 398 399 static int __maybe_unused td043mtea1_resume(struct device *dev) 400 { 401 struct td043mtea1_panel *lcd = dev_get_drvdata(dev); 402 int ret; 403 404 lcd->spi_suspended = false; 405 406 if (lcd->powered_on) { 407 lcd->powered_on = false; 408 ret = td043mtea1_power_on(lcd); 409 if (ret) 410 return ret; 411 } 412 413 return 0; 414 } 415 416 static SIMPLE_DEV_PM_OPS(td043mtea1_pm_ops, td043mtea1_suspend, 417 td043mtea1_resume); 418 419 static int td043mtea1_probe(struct spi_device *spi) 420 { 421 struct td043mtea1_panel *lcd; 422 int ret; 423 424 lcd = devm_kzalloc(&spi->dev, sizeof(*lcd), GFP_KERNEL); 425 if (lcd == NULL) 426 return -ENOMEM; 427 428 spi_set_drvdata(spi, lcd); 429 lcd->spi = spi; 430 lcd->mode = TPO_R02_MODE_800x480; 431 memcpy(lcd->gamma, td043mtea1_def_gamma, sizeof(lcd->gamma)); 432 433 lcd->vcc_reg = devm_regulator_get(&spi->dev, "vcc"); 434 if (IS_ERR(lcd->vcc_reg)) { 435 dev_err(&spi->dev, "failed to get VCC regulator\n"); 436 return PTR_ERR(lcd->vcc_reg); 437 } 438 439 lcd->reset_gpio = devm_gpiod_get(&spi->dev, "reset", GPIOD_OUT_HIGH); 440 if (IS_ERR(lcd->reset_gpio)) { 441 dev_err(&spi->dev, "failed to get reset GPIO\n"); 442 return PTR_ERR(lcd->reset_gpio); 443 } 444 445 spi->bits_per_word = 16; 446 spi->mode = SPI_MODE_0; 447 448 ret = spi_setup(spi); 449 if (ret < 0) { 450 dev_err(&spi->dev, "failed to setup SPI: %d\n", ret); 451 return ret; 452 } 453 454 ret = sysfs_create_group(&spi->dev.kobj, &td043mtea1_attr_group); 455 if (ret < 0) { 456 dev_err(&spi->dev, "failed to create sysfs files\n"); 457 return ret; 458 } 459 460 drm_panel_init(&lcd->panel, &lcd->spi->dev, &td043mtea1_funcs, 461 DRM_MODE_CONNECTOR_DPI); 462 463 ret = drm_panel_add(&lcd->panel); 464 if (ret < 0) { 465 sysfs_remove_group(&spi->dev.kobj, &td043mtea1_attr_group); 466 return ret; 467 } 468 469 return 0; 470 } 471 472 static int td043mtea1_remove(struct spi_device *spi) 473 { 474 struct td043mtea1_panel *lcd = spi_get_drvdata(spi); 475 476 drm_panel_remove(&lcd->panel); 477 drm_panel_disable(&lcd->panel); 478 drm_panel_unprepare(&lcd->panel); 479 480 sysfs_remove_group(&spi->dev.kobj, &td043mtea1_attr_group); 481 482 return 0; 483 } 484 485 static const struct of_device_id td043mtea1_of_match[] = { 486 { .compatible = "tpo,td043mtea1", }, 487 { /* sentinel */ }, 488 }; 489 490 MODULE_DEVICE_TABLE(of, td043mtea1_of_match); 491 492 static const struct spi_device_id td043mtea1_ids[] = { 493 { "td043mtea1", 0 }, 494 { /* sentinel */ } 495 }; 496 497 MODULE_DEVICE_TABLE(spi, td043mtea1_ids); 498 499 static struct spi_driver td043mtea1_driver = { 500 .probe = td043mtea1_probe, 501 .remove = td043mtea1_remove, 502 .id_table = td043mtea1_ids, 503 .driver = { 504 .name = "panel-tpo-td043mtea1", 505 .pm = &td043mtea1_pm_ops, 506 .of_match_table = td043mtea1_of_match, 507 }, 508 }; 509 510 module_spi_driver(td043mtea1_driver); 511 512 MODULE_AUTHOR("Gražvydas Ignotas <notasas@gmail.com>"); 513 MODULE_DESCRIPTION("TPO TD043MTEA1 Panel Driver"); 514 MODULE_LICENSE("GPL"); 515