1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Parade PS8622 eDP/LVDS bridge driver 4 * 5 * Copyright (C) 2014 Google, Inc. 6 */ 7 8 #include <linux/backlight.h> 9 #include <linux/delay.h> 10 #include <linux/err.h> 11 #include <linux/gpio/consumer.h> 12 #include <linux/i2c.h> 13 #include <linux/module.h> 14 #include <linux/of.h> 15 #include <linux/of_device.h> 16 #include <linux/pm.h> 17 #include <linux/regulator/consumer.h> 18 19 #include <drm/drm_atomic_helper.h> 20 #include <drm/drm_crtc.h> 21 #include <drm/drm_of.h> 22 #include <drm/drm_panel.h> 23 #include <drm/drm_print.h> 24 #include <drm/drm_probe_helper.h> 25 26 /* Brightness scale on the Parade chip */ 27 #define PS8622_MAX_BRIGHTNESS 0xff 28 29 /* Timings taken from the version 1.7 datasheet for the PS8622/PS8625 */ 30 #define PS8622_POWER_RISE_T1_MIN_US 10 31 #define PS8622_POWER_RISE_T1_MAX_US 10000 32 #define PS8622_RST_HIGH_T2_MIN_US 3000 33 #define PS8622_RST_HIGH_T2_MAX_US 30000 34 #define PS8622_PWMO_END_T12_MS 200 35 #define PS8622_POWER_FALL_T16_MAX_US 10000 36 #define PS8622_POWER_OFF_T17_MS 500 37 38 #if ((PS8622_RST_HIGH_T2_MIN_US + PS8622_POWER_RISE_T1_MAX_US) > \ 39 (PS8622_RST_HIGH_T2_MAX_US + PS8622_POWER_RISE_T1_MIN_US)) 40 #error "T2.min + T1.max must be less than T2.max + T1.min" 41 #endif 42 43 struct ps8622_bridge { 44 struct drm_connector connector; 45 struct i2c_client *client; 46 struct drm_bridge bridge; 47 struct drm_panel *panel; 48 struct regulator *v12; 49 struct backlight_device *bl; 50 51 struct gpio_desc *gpio_slp; 52 struct gpio_desc *gpio_rst; 53 54 u32 max_lane_count; 55 u32 lane_count; 56 57 bool enabled; 58 }; 59 60 static inline struct ps8622_bridge * 61 bridge_to_ps8622(struct drm_bridge *bridge) 62 { 63 return container_of(bridge, struct ps8622_bridge, bridge); 64 } 65 66 static inline struct ps8622_bridge * 67 connector_to_ps8622(struct drm_connector *connector) 68 { 69 return container_of(connector, struct ps8622_bridge, connector); 70 } 71 72 static int ps8622_set(struct i2c_client *client, u8 page, u8 reg, u8 val) 73 { 74 int ret; 75 struct i2c_adapter *adap = client->adapter; 76 struct i2c_msg msg; 77 u8 data[] = {reg, val}; 78 79 msg.addr = client->addr + page; 80 msg.flags = 0; 81 msg.len = sizeof(data); 82 msg.buf = data; 83 84 ret = i2c_transfer(adap, &msg, 1); 85 if (ret != 1) 86 pr_warn("PS8622 I2C write (0x%02x,0x%02x,0x%02x) failed: %d\n", 87 client->addr + page, reg, val, ret); 88 return !(ret == 1); 89 } 90 91 static int ps8622_send_config(struct ps8622_bridge *ps8622) 92 { 93 struct i2c_client *cl = ps8622->client; 94 int err = 0; 95 96 /* HPD low */ 97 err = ps8622_set(cl, 0x02, 0xa1, 0x01); 98 if (err) 99 goto error; 100 101 /* SW setting: [1:0] SW output 1.2V voltage is lower to 96% */ 102 err = ps8622_set(cl, 0x04, 0x14, 0x01); 103 if (err) 104 goto error; 105 106 /* RCO SS setting: [5:4] = b01 0.5%, b10 1%, b11 1.5% */ 107 err = ps8622_set(cl, 0x04, 0xe3, 0x20); 108 if (err) 109 goto error; 110 111 /* [7] RCO SS enable */ 112 err = ps8622_set(cl, 0x04, 0xe2, 0x80); 113 if (err) 114 goto error; 115 116 /* RPHY Setting 117 * [3:2] CDR tune wait cycle before measure for fine tune 118 * b00: 1us b01: 0.5us b10:2us, b11: 4us 119 */ 120 err = ps8622_set(cl, 0x04, 0x8a, 0x0c); 121 if (err) 122 goto error; 123 124 /* [3] RFD always on */ 125 err = ps8622_set(cl, 0x04, 0x89, 0x08); 126 if (err) 127 goto error; 128 129 /* CTN lock in/out: 20000ppm/80000ppm. Lock out 2 times. */ 130 err = ps8622_set(cl, 0x04, 0x71, 0x2d); 131 if (err) 132 goto error; 133 134 /* 2.7G CDR settings: NOF=40LSB for HBR CDR setting */ 135 err = ps8622_set(cl, 0x04, 0x7d, 0x07); 136 if (err) 137 goto error; 138 139 /* [1:0] Fmin=+4bands */ 140 err = ps8622_set(cl, 0x04, 0x7b, 0x00); 141 if (err) 142 goto error; 143 144 /* [7:5] DCO_FTRNG=+-40% */ 145 err = ps8622_set(cl, 0x04, 0x7a, 0xfd); 146 if (err) 147 goto error; 148 149 /* 1.62G CDR settings: [5:2]NOF=64LSB [1:0]DCO scale is 2/5 */ 150 err = ps8622_set(cl, 0x04, 0xc0, 0x12); 151 if (err) 152 goto error; 153 154 /* Gitune=-37% */ 155 err = ps8622_set(cl, 0x04, 0xc1, 0x92); 156 if (err) 157 goto error; 158 159 /* Fbstep=100% */ 160 err = ps8622_set(cl, 0x04, 0xc2, 0x1c); 161 if (err) 162 goto error; 163 164 /* [7] LOS signal disable */ 165 err = ps8622_set(cl, 0x04, 0x32, 0x80); 166 if (err) 167 goto error; 168 169 /* RPIO Setting: [7:4] LVDS driver bias current : 75% (250mV swing) */ 170 err = ps8622_set(cl, 0x04, 0x00, 0xb0); 171 if (err) 172 goto error; 173 174 /* [7:6] Right-bar GPIO output strength is 8mA */ 175 err = ps8622_set(cl, 0x04, 0x15, 0x40); 176 if (err) 177 goto error; 178 179 /* EQ Training State Machine Setting, RCO calibration start */ 180 err = ps8622_set(cl, 0x04, 0x54, 0x10); 181 if (err) 182 goto error; 183 184 /* Logic, needs more than 10 I2C command */ 185 /* [4:0] MAX_LANE_COUNT set to max supported lanes */ 186 err = ps8622_set(cl, 0x01, 0x02, 0x80 | ps8622->max_lane_count); 187 if (err) 188 goto error; 189 190 /* [4:0] LANE_COUNT_SET set to chosen lane count */ 191 err = ps8622_set(cl, 0x01, 0x21, 0x80 | ps8622->lane_count); 192 if (err) 193 goto error; 194 195 err = ps8622_set(cl, 0x00, 0x52, 0x20); 196 if (err) 197 goto error; 198 199 /* HPD CP toggle enable */ 200 err = ps8622_set(cl, 0x00, 0xf1, 0x03); 201 if (err) 202 goto error; 203 204 err = ps8622_set(cl, 0x00, 0x62, 0x41); 205 if (err) 206 goto error; 207 208 /* Counter number, add 1ms counter delay */ 209 err = ps8622_set(cl, 0x00, 0xf6, 0x01); 210 if (err) 211 goto error; 212 213 /* [6]PWM function control by DPCD0040f[7], default is PWM block */ 214 err = ps8622_set(cl, 0x00, 0x77, 0x06); 215 if (err) 216 goto error; 217 218 /* 04h Adjust VTotal toleranceto fix the 30Hz no display issue */ 219 err = ps8622_set(cl, 0x00, 0x4c, 0x04); 220 if (err) 221 goto error; 222 223 /* DPCD00400='h00, Parade OUI ='h001cf8 */ 224 err = ps8622_set(cl, 0x01, 0xc0, 0x00); 225 if (err) 226 goto error; 227 228 /* DPCD00401='h1c */ 229 err = ps8622_set(cl, 0x01, 0xc1, 0x1c); 230 if (err) 231 goto error; 232 233 /* DPCD00402='hf8 */ 234 err = ps8622_set(cl, 0x01, 0xc2, 0xf8); 235 if (err) 236 goto error; 237 238 /* DPCD403~408 = ASCII code, D2SLV5='h4432534c5635 */ 239 err = ps8622_set(cl, 0x01, 0xc3, 0x44); 240 if (err) 241 goto error; 242 243 /* DPCD404 */ 244 err = ps8622_set(cl, 0x01, 0xc4, 0x32); 245 if (err) 246 goto error; 247 248 /* DPCD405 */ 249 err = ps8622_set(cl, 0x01, 0xc5, 0x53); 250 if (err) 251 goto error; 252 253 /* DPCD406 */ 254 err = ps8622_set(cl, 0x01, 0xc6, 0x4c); 255 if (err) 256 goto error; 257 258 /* DPCD407 */ 259 err = ps8622_set(cl, 0x01, 0xc7, 0x56); 260 if (err) 261 goto error; 262 263 /* DPCD408 */ 264 err = ps8622_set(cl, 0x01, 0xc8, 0x35); 265 if (err) 266 goto error; 267 268 /* DPCD40A, Initial Code major revision '01' */ 269 err = ps8622_set(cl, 0x01, 0xca, 0x01); 270 if (err) 271 goto error; 272 273 /* DPCD40B, Initial Code minor revision '05' */ 274 err = ps8622_set(cl, 0x01, 0xcb, 0x05); 275 if (err) 276 goto error; 277 278 279 if (ps8622->bl) { 280 /* DPCD720, internal PWM */ 281 err = ps8622_set(cl, 0x01, 0xa5, 0xa0); 282 if (err) 283 goto error; 284 285 /* FFh for 100% brightness, 0h for 0% brightness */ 286 err = ps8622_set(cl, 0x01, 0xa7, 287 ps8622->bl->props.brightness); 288 if (err) 289 goto error; 290 } else { 291 /* DPCD720, external PWM */ 292 err = ps8622_set(cl, 0x01, 0xa5, 0x80); 293 if (err) 294 goto error; 295 } 296 297 /* Set LVDS output as 6bit-VESA mapping, single LVDS channel */ 298 err = ps8622_set(cl, 0x01, 0xcc, 0x13); 299 if (err) 300 goto error; 301 302 /* Enable SSC set by register */ 303 err = ps8622_set(cl, 0x02, 0xb1, 0x20); 304 if (err) 305 goto error; 306 307 /* Set SSC enabled and +/-1% central spreading */ 308 err = ps8622_set(cl, 0x04, 0x10, 0x16); 309 if (err) 310 goto error; 311 312 /* Logic end */ 313 /* MPU Clock source: LC => RCO */ 314 err = ps8622_set(cl, 0x04, 0x59, 0x60); 315 if (err) 316 goto error; 317 318 /* LC -> RCO */ 319 err = ps8622_set(cl, 0x04, 0x54, 0x14); 320 if (err) 321 goto error; 322 323 /* HPD high */ 324 err = ps8622_set(cl, 0x02, 0xa1, 0x91); 325 326 error: 327 return err ? -EIO : 0; 328 } 329 330 static int ps8622_backlight_update(struct backlight_device *bl) 331 { 332 struct ps8622_bridge *ps8622 = dev_get_drvdata(&bl->dev); 333 int ret, brightness = bl->props.brightness; 334 335 if (bl->props.power != FB_BLANK_UNBLANK || 336 bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK)) 337 brightness = 0; 338 339 if (!ps8622->enabled) 340 return -EINVAL; 341 342 ret = ps8622_set(ps8622->client, 0x01, 0xa7, brightness); 343 344 return ret; 345 } 346 347 static const struct backlight_ops ps8622_backlight_ops = { 348 .update_status = ps8622_backlight_update, 349 }; 350 351 static void ps8622_pre_enable(struct drm_bridge *bridge) 352 { 353 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 354 int ret; 355 356 if (ps8622->enabled) 357 return; 358 359 gpiod_set_value(ps8622->gpio_rst, 0); 360 361 if (ps8622->v12) { 362 ret = regulator_enable(ps8622->v12); 363 if (ret) 364 DRM_ERROR("fails to enable ps8622->v12"); 365 } 366 367 if (drm_panel_prepare(ps8622->panel)) { 368 DRM_ERROR("failed to prepare panel\n"); 369 return; 370 } 371 372 gpiod_set_value(ps8622->gpio_slp, 1); 373 374 /* 375 * T1 is the range of time that it takes for the power to rise after we 376 * enable the lcd/ps8622 fet. T2 is the range of time in which the 377 * data sheet specifies we should deassert the reset pin. 378 * 379 * If it takes T1.max for the power to rise, we need to wait atleast 380 * T2.min before deasserting the reset pin. If it takes T1.min for the 381 * power to rise, we need to wait at most T2.max before deasserting the 382 * reset pin. 383 */ 384 usleep_range(PS8622_RST_HIGH_T2_MIN_US + PS8622_POWER_RISE_T1_MAX_US, 385 PS8622_RST_HIGH_T2_MAX_US + PS8622_POWER_RISE_T1_MIN_US); 386 387 gpiod_set_value(ps8622->gpio_rst, 1); 388 389 /* wait 20ms after RST high */ 390 usleep_range(20000, 30000); 391 392 ret = ps8622_send_config(ps8622); 393 if (ret) { 394 DRM_ERROR("Failed to send config to bridge (%d)\n", ret); 395 return; 396 } 397 398 ps8622->enabled = true; 399 } 400 401 static void ps8622_enable(struct drm_bridge *bridge) 402 { 403 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 404 405 if (drm_panel_enable(ps8622->panel)) { 406 DRM_ERROR("failed to enable panel\n"); 407 return; 408 } 409 } 410 411 static void ps8622_disable(struct drm_bridge *bridge) 412 { 413 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 414 415 if (drm_panel_disable(ps8622->panel)) { 416 DRM_ERROR("failed to disable panel\n"); 417 return; 418 } 419 msleep(PS8622_PWMO_END_T12_MS); 420 } 421 422 static void ps8622_post_disable(struct drm_bridge *bridge) 423 { 424 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 425 426 if (!ps8622->enabled) 427 return; 428 429 ps8622->enabled = false; 430 431 /* 432 * This doesn't matter if the regulators are turned off, but something 433 * else might keep them on. In that case, we want to assert the slp gpio 434 * to lower power. 435 */ 436 gpiod_set_value(ps8622->gpio_slp, 0); 437 438 if (drm_panel_unprepare(ps8622->panel)) { 439 DRM_ERROR("failed to unprepare panel\n"); 440 return; 441 } 442 443 if (ps8622->v12) 444 regulator_disable(ps8622->v12); 445 446 /* 447 * Sleep for at least the amount of time that it takes the power rail to 448 * fall to prevent asserting the rst gpio from doing anything. 449 */ 450 usleep_range(PS8622_POWER_FALL_T16_MAX_US, 451 2 * PS8622_POWER_FALL_T16_MAX_US); 452 gpiod_set_value(ps8622->gpio_rst, 0); 453 454 msleep(PS8622_POWER_OFF_T17_MS); 455 } 456 457 static int ps8622_get_modes(struct drm_connector *connector) 458 { 459 struct ps8622_bridge *ps8622; 460 461 ps8622 = connector_to_ps8622(connector); 462 463 return drm_panel_get_modes(ps8622->panel); 464 } 465 466 static const struct drm_connector_helper_funcs ps8622_connector_helper_funcs = { 467 .get_modes = ps8622_get_modes, 468 }; 469 470 static const struct drm_connector_funcs ps8622_connector_funcs = { 471 .fill_modes = drm_helper_probe_single_connector_modes, 472 .destroy = drm_connector_cleanup, 473 .reset = drm_atomic_helper_connector_reset, 474 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, 475 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, 476 }; 477 478 static int ps8622_attach(struct drm_bridge *bridge) 479 { 480 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 481 int ret; 482 483 if (!bridge->encoder) { 484 DRM_ERROR("Parent encoder object not found"); 485 return -ENODEV; 486 } 487 488 ps8622->connector.polled = DRM_CONNECTOR_POLL_HPD; 489 ret = drm_connector_init(bridge->dev, &ps8622->connector, 490 &ps8622_connector_funcs, DRM_MODE_CONNECTOR_LVDS); 491 if (ret) { 492 DRM_ERROR("Failed to initialize connector with drm\n"); 493 return ret; 494 } 495 drm_connector_helper_add(&ps8622->connector, 496 &ps8622_connector_helper_funcs); 497 drm_connector_register(&ps8622->connector); 498 drm_connector_attach_encoder(&ps8622->connector, 499 bridge->encoder); 500 501 if (ps8622->panel) 502 drm_panel_attach(ps8622->panel, &ps8622->connector); 503 504 drm_helper_hpd_irq_event(ps8622->connector.dev); 505 506 return ret; 507 } 508 509 static const struct drm_bridge_funcs ps8622_bridge_funcs = { 510 .pre_enable = ps8622_pre_enable, 511 .enable = ps8622_enable, 512 .disable = ps8622_disable, 513 .post_disable = ps8622_post_disable, 514 .attach = ps8622_attach, 515 }; 516 517 static const struct of_device_id ps8622_devices[] = { 518 {.compatible = "parade,ps8622",}, 519 {.compatible = "parade,ps8625",}, 520 {} 521 }; 522 MODULE_DEVICE_TABLE(of, ps8622_devices); 523 524 static int ps8622_probe(struct i2c_client *client, 525 const struct i2c_device_id *id) 526 { 527 struct device *dev = &client->dev; 528 struct ps8622_bridge *ps8622; 529 int ret; 530 531 ps8622 = devm_kzalloc(dev, sizeof(*ps8622), GFP_KERNEL); 532 if (!ps8622) 533 return -ENOMEM; 534 535 ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0, &ps8622->panel, NULL); 536 if (ret) 537 return ret; 538 539 ps8622->client = client; 540 541 ps8622->v12 = devm_regulator_get(dev, "vdd12"); 542 if (IS_ERR(ps8622->v12)) { 543 dev_info(dev, "no 1.2v regulator found for PS8622\n"); 544 ps8622->v12 = NULL; 545 } 546 547 ps8622->gpio_slp = devm_gpiod_get(dev, "sleep", GPIOD_OUT_HIGH); 548 if (IS_ERR(ps8622->gpio_slp)) { 549 ret = PTR_ERR(ps8622->gpio_slp); 550 dev_err(dev, "cannot get gpio_slp %d\n", ret); 551 return ret; 552 } 553 554 /* 555 * Assert the reset pin high to avoid the bridge being 556 * initialized prematurely 557 */ 558 ps8622->gpio_rst = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); 559 if (IS_ERR(ps8622->gpio_rst)) { 560 ret = PTR_ERR(ps8622->gpio_rst); 561 dev_err(dev, "cannot get gpio_rst %d\n", ret); 562 return ret; 563 } 564 565 ps8622->max_lane_count = id->driver_data; 566 567 if (of_property_read_u32(dev->of_node, "lane-count", 568 &ps8622->lane_count)) { 569 ps8622->lane_count = ps8622->max_lane_count; 570 } else if (ps8622->lane_count > ps8622->max_lane_count) { 571 dev_info(dev, "lane-count property is too high," 572 "using max_lane_count\n"); 573 ps8622->lane_count = ps8622->max_lane_count; 574 } 575 576 if (!of_find_property(dev->of_node, "use-external-pwm", NULL)) { 577 ps8622->bl = backlight_device_register("ps8622-backlight", 578 dev, ps8622, &ps8622_backlight_ops, 579 NULL); 580 if (IS_ERR(ps8622->bl)) { 581 DRM_ERROR("failed to register backlight\n"); 582 ret = PTR_ERR(ps8622->bl); 583 ps8622->bl = NULL; 584 return ret; 585 } 586 ps8622->bl->props.max_brightness = PS8622_MAX_BRIGHTNESS; 587 ps8622->bl->props.brightness = PS8622_MAX_BRIGHTNESS; 588 } 589 590 ps8622->bridge.funcs = &ps8622_bridge_funcs; 591 ps8622->bridge.of_node = dev->of_node; 592 drm_bridge_add(&ps8622->bridge); 593 594 i2c_set_clientdata(client, ps8622); 595 596 return 0; 597 } 598 599 static int ps8622_remove(struct i2c_client *client) 600 { 601 struct ps8622_bridge *ps8622 = i2c_get_clientdata(client); 602 603 backlight_device_unregister(ps8622->bl); 604 drm_bridge_remove(&ps8622->bridge); 605 606 return 0; 607 } 608 609 static const struct i2c_device_id ps8622_i2c_table[] = { 610 /* Device type, max_lane_count */ 611 {"ps8622", 1}, 612 {"ps8625", 2}, 613 {}, 614 }; 615 MODULE_DEVICE_TABLE(i2c, ps8622_i2c_table); 616 617 static struct i2c_driver ps8622_driver = { 618 .id_table = ps8622_i2c_table, 619 .probe = ps8622_probe, 620 .remove = ps8622_remove, 621 .driver = { 622 .name = "ps8622", 623 .of_match_table = ps8622_devices, 624 }, 625 }; 626 module_i2c_driver(ps8622_driver); 627 628 MODULE_AUTHOR("Vincent Palatin <vpalatin@chromium.org>"); 629 MODULE_DESCRIPTION("Parade ps8622/ps8625 eDP-LVDS converter driver"); 630 MODULE_LICENSE("GPL v2"); 631