1 /* 2 * Parade PS8622 eDP/LVDS bridge driver 3 * 4 * Copyright (C) 2014 Google, Inc. 5 * 6 * This software is licensed under the terms of the GNU General Public 7 * License version 2, as published by the Free Software Foundation, and 8 * may be copied, distributed, and modified under those terms. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 */ 15 16 #include <linux/backlight.h> 17 #include <linux/delay.h> 18 #include <linux/err.h> 19 #include <linux/fb.h> 20 #include <linux/gpio.h> 21 #include <linux/gpio/consumer.h> 22 #include <linux/i2c.h> 23 #include <linux/module.h> 24 #include <linux/of.h> 25 #include <linux/of_device.h> 26 #include <linux/of_graph.h> 27 #include <linux/pm.h> 28 #include <linux/regulator/consumer.h> 29 30 #include <drm/drm_panel.h> 31 32 #include "drmP.h" 33 #include "drm_crtc.h" 34 #include "drm_crtc_helper.h" 35 #include "drm_atomic_helper.h" 36 37 /* Brightness scale on the Parade chip */ 38 #define PS8622_MAX_BRIGHTNESS 0xff 39 40 /* Timings taken from the version 1.7 datasheet for the PS8622/PS8625 */ 41 #define PS8622_POWER_RISE_T1_MIN_US 10 42 #define PS8622_POWER_RISE_T1_MAX_US 10000 43 #define PS8622_RST_HIGH_T2_MIN_US 3000 44 #define PS8622_RST_HIGH_T2_MAX_US 30000 45 #define PS8622_PWMO_END_T12_MS 200 46 #define PS8622_POWER_FALL_T16_MAX_US 10000 47 #define PS8622_POWER_OFF_T17_MS 500 48 49 #if ((PS8622_RST_HIGH_T2_MIN_US + PS8622_POWER_RISE_T1_MAX_US) > \ 50 (PS8622_RST_HIGH_T2_MAX_US + PS8622_POWER_RISE_T1_MIN_US)) 51 #error "T2.min + T1.max must be less than T2.max + T1.min" 52 #endif 53 54 struct ps8622_bridge { 55 struct drm_connector connector; 56 struct i2c_client *client; 57 struct drm_bridge bridge; 58 struct drm_panel *panel; 59 struct regulator *v12; 60 struct backlight_device *bl; 61 62 struct gpio_desc *gpio_slp; 63 struct gpio_desc *gpio_rst; 64 65 u32 max_lane_count; 66 u32 lane_count; 67 68 bool enabled; 69 }; 70 71 static inline struct ps8622_bridge * 72 bridge_to_ps8622(struct drm_bridge *bridge) 73 { 74 return container_of(bridge, struct ps8622_bridge, bridge); 75 } 76 77 static inline struct ps8622_bridge * 78 connector_to_ps8622(struct drm_connector *connector) 79 { 80 return container_of(connector, struct ps8622_bridge, connector); 81 } 82 83 static int ps8622_set(struct i2c_client *client, u8 page, u8 reg, u8 val) 84 { 85 int ret; 86 struct i2c_adapter *adap = client->adapter; 87 struct i2c_msg msg; 88 u8 data[] = {reg, val}; 89 90 msg.addr = client->addr + page; 91 msg.flags = 0; 92 msg.len = sizeof(data); 93 msg.buf = data; 94 95 ret = i2c_transfer(adap, &msg, 1); 96 if (ret != 1) 97 pr_warn("PS8622 I2C write (0x%02x,0x%02x,0x%02x) failed: %d\n", 98 client->addr + page, reg, val, ret); 99 return !(ret == 1); 100 } 101 102 static int ps8622_send_config(struct ps8622_bridge *ps8622) 103 { 104 struct i2c_client *cl = ps8622->client; 105 int err = 0; 106 107 /* HPD low */ 108 err = ps8622_set(cl, 0x02, 0xa1, 0x01); 109 if (err) 110 goto error; 111 112 /* SW setting: [1:0] SW output 1.2V voltage is lower to 96% */ 113 err = ps8622_set(cl, 0x04, 0x14, 0x01); 114 if (err) 115 goto error; 116 117 /* RCO SS setting: [5:4] = b01 0.5%, b10 1%, b11 1.5% */ 118 err = ps8622_set(cl, 0x04, 0xe3, 0x20); 119 if (err) 120 goto error; 121 122 /* [7] RCO SS enable */ 123 err = ps8622_set(cl, 0x04, 0xe2, 0x80); 124 if (err) 125 goto error; 126 127 /* RPHY Setting 128 * [3:2] CDR tune wait cycle before measure for fine tune 129 * b00: 1us b01: 0.5us b10:2us, b11: 4us 130 */ 131 err = ps8622_set(cl, 0x04, 0x8a, 0x0c); 132 if (err) 133 goto error; 134 135 /* [3] RFD always on */ 136 err = ps8622_set(cl, 0x04, 0x89, 0x08); 137 if (err) 138 goto error; 139 140 /* CTN lock in/out: 20000ppm/80000ppm. Lock out 2 times. */ 141 err = ps8622_set(cl, 0x04, 0x71, 0x2d); 142 if (err) 143 goto error; 144 145 /* 2.7G CDR settings: NOF=40LSB for HBR CDR setting */ 146 err = ps8622_set(cl, 0x04, 0x7d, 0x07); 147 if (err) 148 goto error; 149 150 /* [1:0] Fmin=+4bands */ 151 err = ps8622_set(cl, 0x04, 0x7b, 0x00); 152 if (err) 153 goto error; 154 155 /* [7:5] DCO_FTRNG=+-40% */ 156 err = ps8622_set(cl, 0x04, 0x7a, 0xfd); 157 if (err) 158 goto error; 159 160 /* 1.62G CDR settings: [5:2]NOF=64LSB [1:0]DCO scale is 2/5 */ 161 err = ps8622_set(cl, 0x04, 0xc0, 0x12); 162 if (err) 163 goto error; 164 165 /* Gitune=-37% */ 166 err = ps8622_set(cl, 0x04, 0xc1, 0x92); 167 if (err) 168 goto error; 169 170 /* Fbstep=100% */ 171 err = ps8622_set(cl, 0x04, 0xc2, 0x1c); 172 if (err) 173 goto error; 174 175 /* [7] LOS signal disable */ 176 err = ps8622_set(cl, 0x04, 0x32, 0x80); 177 if (err) 178 goto error; 179 180 /* RPIO Setting: [7:4] LVDS driver bias current : 75% (250mV swing) */ 181 err = ps8622_set(cl, 0x04, 0x00, 0xb0); 182 if (err) 183 goto error; 184 185 /* [7:6] Right-bar GPIO output strength is 8mA */ 186 err = ps8622_set(cl, 0x04, 0x15, 0x40); 187 if (err) 188 goto error; 189 190 /* EQ Training State Machine Setting, RCO calibration start */ 191 err = ps8622_set(cl, 0x04, 0x54, 0x10); 192 if (err) 193 goto error; 194 195 /* Logic, needs more than 10 I2C command */ 196 /* [4:0] MAX_LANE_COUNT set to max supported lanes */ 197 err = ps8622_set(cl, 0x01, 0x02, 0x80 | ps8622->max_lane_count); 198 if (err) 199 goto error; 200 201 /* [4:0] LANE_COUNT_SET set to chosen lane count */ 202 err = ps8622_set(cl, 0x01, 0x21, 0x80 | ps8622->lane_count); 203 if (err) 204 goto error; 205 206 err = ps8622_set(cl, 0x00, 0x52, 0x20); 207 if (err) 208 goto error; 209 210 /* HPD CP toggle enable */ 211 err = ps8622_set(cl, 0x00, 0xf1, 0x03); 212 if (err) 213 goto error; 214 215 err = ps8622_set(cl, 0x00, 0x62, 0x41); 216 if (err) 217 goto error; 218 219 /* Counter number, add 1ms counter delay */ 220 err = ps8622_set(cl, 0x00, 0xf6, 0x01); 221 if (err) 222 goto error; 223 224 /* [6]PWM function control by DPCD0040f[7], default is PWM block */ 225 err = ps8622_set(cl, 0x00, 0x77, 0x06); 226 if (err) 227 goto error; 228 229 /* 04h Adjust VTotal toleranceto fix the 30Hz no display issue */ 230 err = ps8622_set(cl, 0x00, 0x4c, 0x04); 231 if (err) 232 goto error; 233 234 /* DPCD00400='h00, Parade OUI ='h001cf8 */ 235 err = ps8622_set(cl, 0x01, 0xc0, 0x00); 236 if (err) 237 goto error; 238 239 /* DPCD00401='h1c */ 240 err = ps8622_set(cl, 0x01, 0xc1, 0x1c); 241 if (err) 242 goto error; 243 244 /* DPCD00402='hf8 */ 245 err = ps8622_set(cl, 0x01, 0xc2, 0xf8); 246 if (err) 247 goto error; 248 249 /* DPCD403~408 = ASCII code, D2SLV5='h4432534c5635 */ 250 err = ps8622_set(cl, 0x01, 0xc3, 0x44); 251 if (err) 252 goto error; 253 254 /* DPCD404 */ 255 err = ps8622_set(cl, 0x01, 0xc4, 0x32); 256 if (err) 257 goto error; 258 259 /* DPCD405 */ 260 err = ps8622_set(cl, 0x01, 0xc5, 0x53); 261 if (err) 262 goto error; 263 264 /* DPCD406 */ 265 err = ps8622_set(cl, 0x01, 0xc6, 0x4c); 266 if (err) 267 goto error; 268 269 /* DPCD407 */ 270 err = ps8622_set(cl, 0x01, 0xc7, 0x56); 271 if (err) 272 goto error; 273 274 /* DPCD408 */ 275 err = ps8622_set(cl, 0x01, 0xc8, 0x35); 276 if (err) 277 goto error; 278 279 /* DPCD40A, Initial Code major revision '01' */ 280 err = ps8622_set(cl, 0x01, 0xca, 0x01); 281 if (err) 282 goto error; 283 284 /* DPCD40B, Initial Code minor revision '05' */ 285 err = ps8622_set(cl, 0x01, 0xcb, 0x05); 286 if (err) 287 goto error; 288 289 290 if (ps8622->bl) { 291 /* DPCD720, internal PWM */ 292 err = ps8622_set(cl, 0x01, 0xa5, 0xa0); 293 if (err) 294 goto error; 295 296 /* FFh for 100% brightness, 0h for 0% brightness */ 297 err = ps8622_set(cl, 0x01, 0xa7, 298 ps8622->bl->props.brightness); 299 if (err) 300 goto error; 301 } else { 302 /* DPCD720, external PWM */ 303 err = ps8622_set(cl, 0x01, 0xa5, 0x80); 304 if (err) 305 goto error; 306 } 307 308 /* Set LVDS output as 6bit-VESA mapping, single LVDS channel */ 309 err = ps8622_set(cl, 0x01, 0xcc, 0x13); 310 if (err) 311 goto error; 312 313 /* Enable SSC set by register */ 314 err = ps8622_set(cl, 0x02, 0xb1, 0x20); 315 if (err) 316 goto error; 317 318 /* Set SSC enabled and +/-1% central spreading */ 319 err = ps8622_set(cl, 0x04, 0x10, 0x16); 320 if (err) 321 goto error; 322 323 /* Logic end */ 324 /* MPU Clock source: LC => RCO */ 325 err = ps8622_set(cl, 0x04, 0x59, 0x60); 326 if (err) 327 goto error; 328 329 /* LC -> RCO */ 330 err = ps8622_set(cl, 0x04, 0x54, 0x14); 331 if (err) 332 goto error; 333 334 /* HPD high */ 335 err = ps8622_set(cl, 0x02, 0xa1, 0x91); 336 337 error: 338 return err ? -EIO : 0; 339 } 340 341 static int ps8622_backlight_update(struct backlight_device *bl) 342 { 343 struct ps8622_bridge *ps8622 = dev_get_drvdata(&bl->dev); 344 int ret, brightness = bl->props.brightness; 345 346 if (bl->props.power != FB_BLANK_UNBLANK || 347 bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK)) 348 brightness = 0; 349 350 if (!ps8622->enabled) 351 return -EINVAL; 352 353 ret = ps8622_set(ps8622->client, 0x01, 0xa7, brightness); 354 355 return ret; 356 } 357 358 static const struct backlight_ops ps8622_backlight_ops = { 359 .update_status = ps8622_backlight_update, 360 }; 361 362 static void ps8622_pre_enable(struct drm_bridge *bridge) 363 { 364 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 365 int ret; 366 367 if (ps8622->enabled) 368 return; 369 370 gpiod_set_value(ps8622->gpio_rst, 0); 371 372 if (ps8622->v12) { 373 ret = regulator_enable(ps8622->v12); 374 if (ret) 375 DRM_ERROR("fails to enable ps8622->v12"); 376 } 377 378 if (drm_panel_prepare(ps8622->panel)) { 379 DRM_ERROR("failed to prepare panel\n"); 380 return; 381 } 382 383 gpiod_set_value(ps8622->gpio_slp, 1); 384 385 /* 386 * T1 is the range of time that it takes for the power to rise after we 387 * enable the lcd/ps8622 fet. T2 is the range of time in which the 388 * data sheet specifies we should deassert the reset pin. 389 * 390 * If it takes T1.max for the power to rise, we need to wait atleast 391 * T2.min before deasserting the reset pin. If it takes T1.min for the 392 * power to rise, we need to wait at most T2.max before deasserting the 393 * reset pin. 394 */ 395 usleep_range(PS8622_RST_HIGH_T2_MIN_US + PS8622_POWER_RISE_T1_MAX_US, 396 PS8622_RST_HIGH_T2_MAX_US + PS8622_POWER_RISE_T1_MIN_US); 397 398 gpiod_set_value(ps8622->gpio_rst, 1); 399 400 /* wait 20ms after RST high */ 401 usleep_range(20000, 30000); 402 403 ret = ps8622_send_config(ps8622); 404 if (ret) { 405 DRM_ERROR("Failed to send config to bridge (%d)\n", ret); 406 return; 407 } 408 409 ps8622->enabled = true; 410 } 411 412 static void ps8622_enable(struct drm_bridge *bridge) 413 { 414 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 415 416 if (drm_panel_enable(ps8622->panel)) { 417 DRM_ERROR("failed to enable panel\n"); 418 return; 419 } 420 } 421 422 static void ps8622_disable(struct drm_bridge *bridge) 423 { 424 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 425 426 if (drm_panel_disable(ps8622->panel)) { 427 DRM_ERROR("failed to disable panel\n"); 428 return; 429 } 430 msleep(PS8622_PWMO_END_T12_MS); 431 } 432 433 static void ps8622_post_disable(struct drm_bridge *bridge) 434 { 435 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 436 437 if (!ps8622->enabled) 438 return; 439 440 ps8622->enabled = false; 441 442 /* 443 * This doesn't matter if the regulators are turned off, but something 444 * else might keep them on. In that case, we want to assert the slp gpio 445 * to lower power. 446 */ 447 gpiod_set_value(ps8622->gpio_slp, 0); 448 449 if (drm_panel_unprepare(ps8622->panel)) { 450 DRM_ERROR("failed to unprepare panel\n"); 451 return; 452 } 453 454 if (ps8622->v12) 455 regulator_disable(ps8622->v12); 456 457 /* 458 * Sleep for at least the amount of time that it takes the power rail to 459 * fall to prevent asserting the rst gpio from doing anything. 460 */ 461 usleep_range(PS8622_POWER_FALL_T16_MAX_US, 462 2 * PS8622_POWER_FALL_T16_MAX_US); 463 gpiod_set_value(ps8622->gpio_rst, 0); 464 465 msleep(PS8622_POWER_OFF_T17_MS); 466 } 467 468 static int ps8622_get_modes(struct drm_connector *connector) 469 { 470 struct ps8622_bridge *ps8622; 471 472 ps8622 = connector_to_ps8622(connector); 473 474 return drm_panel_get_modes(ps8622->panel); 475 } 476 477 static struct drm_encoder *ps8622_best_encoder(struct drm_connector *connector) 478 { 479 struct ps8622_bridge *ps8622; 480 481 ps8622 = connector_to_ps8622(connector); 482 483 return ps8622->bridge.encoder; 484 } 485 486 static const struct drm_connector_helper_funcs ps8622_connector_helper_funcs = { 487 .get_modes = ps8622_get_modes, 488 .best_encoder = ps8622_best_encoder, 489 }; 490 491 static enum drm_connector_status ps8622_detect(struct drm_connector *connector, 492 bool force) 493 { 494 return connector_status_connected; 495 } 496 497 static void ps8622_connector_destroy(struct drm_connector *connector) 498 { 499 drm_connector_cleanup(connector); 500 } 501 502 static const struct drm_connector_funcs ps8622_connector_funcs = { 503 .dpms = drm_atomic_helper_connector_dpms, 504 .fill_modes = drm_helper_probe_single_connector_modes, 505 .detect = ps8622_detect, 506 .destroy = ps8622_connector_destroy, 507 .reset = drm_atomic_helper_connector_reset, 508 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, 509 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, 510 }; 511 512 static int ps8622_attach(struct drm_bridge *bridge) 513 { 514 struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge); 515 int ret; 516 517 if (!bridge->encoder) { 518 DRM_ERROR("Parent encoder object not found"); 519 return -ENODEV; 520 } 521 522 ps8622->connector.polled = DRM_CONNECTOR_POLL_HPD; 523 ret = drm_connector_init(bridge->dev, &ps8622->connector, 524 &ps8622_connector_funcs, DRM_MODE_CONNECTOR_LVDS); 525 if (ret) { 526 DRM_ERROR("Failed to initialize connector with drm\n"); 527 return ret; 528 } 529 drm_connector_helper_add(&ps8622->connector, 530 &ps8622_connector_helper_funcs); 531 drm_connector_register(&ps8622->connector); 532 drm_mode_connector_attach_encoder(&ps8622->connector, 533 bridge->encoder); 534 535 if (ps8622->panel) 536 drm_panel_attach(ps8622->panel, &ps8622->connector); 537 538 drm_helper_hpd_irq_event(ps8622->connector.dev); 539 540 return ret; 541 } 542 543 static const struct drm_bridge_funcs ps8622_bridge_funcs = { 544 .pre_enable = ps8622_pre_enable, 545 .enable = ps8622_enable, 546 .disable = ps8622_disable, 547 .post_disable = ps8622_post_disable, 548 .attach = ps8622_attach, 549 }; 550 551 static const struct of_device_id ps8622_devices[] = { 552 {.compatible = "parade,ps8622",}, 553 {.compatible = "parade,ps8625",}, 554 {} 555 }; 556 MODULE_DEVICE_TABLE(of, ps8622_devices); 557 558 static int ps8622_probe(struct i2c_client *client, 559 const struct i2c_device_id *id) 560 { 561 struct device *dev = &client->dev; 562 struct device_node *endpoint, *panel_node; 563 struct ps8622_bridge *ps8622; 564 int ret; 565 566 ps8622 = devm_kzalloc(dev, sizeof(*ps8622), GFP_KERNEL); 567 if (!ps8622) 568 return -ENOMEM; 569 570 endpoint = of_graph_get_next_endpoint(dev->of_node, NULL); 571 if (endpoint) { 572 panel_node = of_graph_get_remote_port_parent(endpoint); 573 if (panel_node) { 574 ps8622->panel = of_drm_find_panel(panel_node); 575 of_node_put(panel_node); 576 if (!ps8622->panel) 577 return -EPROBE_DEFER; 578 } 579 } 580 581 ps8622->client = client; 582 583 ps8622->v12 = devm_regulator_get(dev, "vdd12"); 584 if (IS_ERR(ps8622->v12)) { 585 dev_info(dev, "no 1.2v regulator found for PS8622\n"); 586 ps8622->v12 = NULL; 587 } 588 589 ps8622->gpio_slp = devm_gpiod_get(dev, "sleep", GPIOD_OUT_HIGH); 590 if (IS_ERR(ps8622->gpio_slp)) { 591 ret = PTR_ERR(ps8622->gpio_slp); 592 dev_err(dev, "cannot get gpio_slp %d\n", ret); 593 return ret; 594 } 595 596 /* 597 * Assert the reset pin high to avoid the bridge being 598 * initialized prematurely 599 */ 600 ps8622->gpio_rst = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); 601 if (IS_ERR(ps8622->gpio_rst)) { 602 ret = PTR_ERR(ps8622->gpio_rst); 603 dev_err(dev, "cannot get gpio_rst %d\n", ret); 604 return ret; 605 } 606 607 ps8622->max_lane_count = id->driver_data; 608 609 if (of_property_read_u32(dev->of_node, "lane-count", 610 &ps8622->lane_count)) { 611 ps8622->lane_count = ps8622->max_lane_count; 612 } else if (ps8622->lane_count > ps8622->max_lane_count) { 613 dev_info(dev, "lane-count property is too high," 614 "using max_lane_count\n"); 615 ps8622->lane_count = ps8622->max_lane_count; 616 } 617 618 if (!of_find_property(dev->of_node, "use-external-pwm", NULL)) { 619 ps8622->bl = backlight_device_register("ps8622-backlight", 620 dev, ps8622, &ps8622_backlight_ops, 621 NULL); 622 if (IS_ERR(ps8622->bl)) { 623 DRM_ERROR("failed to register backlight\n"); 624 ret = PTR_ERR(ps8622->bl); 625 ps8622->bl = NULL; 626 return ret; 627 } 628 ps8622->bl->props.max_brightness = PS8622_MAX_BRIGHTNESS; 629 ps8622->bl->props.brightness = PS8622_MAX_BRIGHTNESS; 630 } 631 632 ps8622->bridge.funcs = &ps8622_bridge_funcs; 633 ps8622->bridge.of_node = dev->of_node; 634 ret = drm_bridge_add(&ps8622->bridge); 635 if (ret) { 636 DRM_ERROR("Failed to add bridge\n"); 637 return ret; 638 } 639 640 i2c_set_clientdata(client, ps8622); 641 642 return 0; 643 } 644 645 static int ps8622_remove(struct i2c_client *client) 646 { 647 struct ps8622_bridge *ps8622 = i2c_get_clientdata(client); 648 649 if (ps8622->bl) 650 backlight_device_unregister(ps8622->bl); 651 652 drm_bridge_remove(&ps8622->bridge); 653 654 return 0; 655 } 656 657 static const struct i2c_device_id ps8622_i2c_table[] = { 658 /* Device type, max_lane_count */ 659 {"ps8622", 1}, 660 {"ps8625", 2}, 661 {}, 662 }; 663 MODULE_DEVICE_TABLE(i2c, ps8622_i2c_table); 664 665 static struct i2c_driver ps8622_driver = { 666 .id_table = ps8622_i2c_table, 667 .probe = ps8622_probe, 668 .remove = ps8622_remove, 669 .driver = { 670 .name = "ps8622", 671 .owner = THIS_MODULE, 672 .of_match_table = ps8622_devices, 673 }, 674 }; 675 module_i2c_driver(ps8622_driver); 676 677 MODULE_AUTHOR("Vincent Palatin <vpalatin@chromium.org>"); 678 MODULE_DESCRIPTION("Parade ps8622/ps8625 eDP-LVDS converter driver"); 679 MODULE_LICENSE("GPL v2"); 680