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