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

   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");