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