drivers/gpu/drm/bridge/parade-ps8622.c

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