drivers/gpu/drm/bridge/parade-ps8640.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2016 MediaTek Inc.
   4  */
   5
   6 #include <linux/delay.h>
   7 #include <linux/err.h>
   8 #include <linux/gpio/consumer.h>
   9 #include <linux/i2c.h>
  10 #include <linux/module.h>
  11 #include <linux/of_graph.h>
  12 #include <linux/pm_runtime.h>
  13 #include <linux/regmap.h>
  14 #include <linux/regulator/consumer.h>
  15
  16 #include <drm/display/drm_dp_aux_bus.h>
  17 #include <drm/display/drm_dp_helper.h>
  18 #include <drm/drm_atomic_state_helper.h>
  19 #include <drm/drm_bridge.h>
  20 #include <drm/drm_edid.h>
  21 #include <drm/drm_mipi_dsi.h>
  22 #include <drm/drm_of.h>
  23 #include <drm/drm_panel.h>
  24 #include <drm/drm_print.h>
  25
  26 #define PAGE0_AUXCH_CFG3        0x76
  27 #define  AUXCH_CFG3_RESET       0xff
  28 #define PAGE0_SWAUX_ADDR_7_0    0x7d
  29 #define PAGE0_SWAUX_ADDR_15_8   0x7e
  30 #define PAGE0_SWAUX_ADDR_23_16  0x7f
  31 #define  SWAUX_ADDR_MASK        GENMASK(19, 0)
  32 #define PAGE0_SWAUX_LENGTH      0x80
  33 #define  SWAUX_LENGTH_MASK      GENMASK(3, 0)
  34 #define  SWAUX_NO_PAYLOAD       BIT(7)
  35 #define PAGE0_SWAUX_WDATA       0x81
  36 #define PAGE0_SWAUX_RDATA       0x82
  37 #define PAGE0_SWAUX_CTRL        0x83
  38 #define  SWAUX_SEND             BIT(0)
  39 #define PAGE0_SWAUX_STATUS      0x84
  40 #define  SWAUX_M_MASK           GENMASK(4, 0)
  41 #define  SWAUX_STATUS_MASK      GENMASK(7, 5)
  42 #define  SWAUX_STATUS_NACK      (0x1 << 5)
  43 #define  SWAUX_STATUS_DEFER     (0x2 << 5)
  44 #define  SWAUX_STATUS_ACKM      (0x3 << 5)
  45 #define  SWAUX_STATUS_INVALID   (0x4 << 5)
  46 #define  SWAUX_STATUS_I2C_NACK  (0x5 << 5)
  47 #define  SWAUX_STATUS_I2C_DEFER (0x6 << 5)
  48 #define  SWAUX_STATUS_TIMEOUT   (0x7 << 5)
  49
  50 #define PAGE2_GPIO_H            0xa7
  51 #define  PS_GPIO9               BIT(1)
  52 #define PAGE2_I2C_BYPASS        0xea
  53 #define  I2C_BYPASS_EN          0xd0
  54 #define PAGE2_MCS_EN            0xf3
  55 #define  MCS_EN                 BIT(0)
  56
  57 #define PAGE3_SET_ADD           0xfe
  58 #define  VDO_CTL_ADD            0x13
  59 #define  VDO_DIS                0x18
  60 #define  VDO_EN                 0x1c
  61
  62 #define NUM_MIPI_LANES          4
  63
  64 #define COMMON_PS8640_REGMAP_CONFIG \
  65         .reg_bits = 8, \
  66         .val_bits = 8, \
  67         .cache_type = REGCACHE_NONE
  68
  69 /*
  70  * PS8640 uses multiple addresses:
  71  * page[0]: for DP control
  72  * page[1]: for VIDEO Bridge
  73  * page[2]: for control top
  74  * page[3]: for DSI Link Control1
  75  * page[4]: for MIPI Phy
  76  * page[5]: for VPLL
  77  * page[6]: for DSI Link Control2
  78  * page[7]: for SPI ROM mapping
  79  */
  80 enum page_addr_offset {
  81         PAGE0_DP_CNTL = 0,
  82         PAGE1_VDO_BDG,
  83         PAGE2_TOP_CNTL,
  84         PAGE3_DSI_CNTL1,
  85         PAGE4_MIPI_PHY,
  86         PAGE5_VPLL,
  87         PAGE6_DSI_CNTL2,
  88         PAGE7_SPI_CNTL,
  89         MAX_DEVS
  90 };
  91
  92 enum ps8640_vdo_control {
  93         DISABLE = VDO_DIS,
  94         ENABLE = VDO_EN,
  95 };
  96
  97 struct ps8640 {
  98         struct drm_bridge bridge;
  99         struct drm_bridge *panel_bridge;
 100         struct drm_dp_aux aux;
 101         struct mipi_dsi_device *dsi;
 102         struct i2c_client *page[MAX_DEVS];
 103         struct regmap   *regmap[MAX_DEVS];
 104         struct regulator_bulk_data supplies[2];
 105         struct gpio_desc *gpio_reset;
 106         struct gpio_desc *gpio_powerdown;
 107         struct device_link *link;
 108         bool pre_enabled;
 109         bool need_post_hpd_delay;
 110 };
 111
 112 static const struct regmap_config ps8640_regmap_config[] = {
 113         [PAGE0_DP_CNTL] = {
 114                 COMMON_PS8640_REGMAP_CONFIG,
 115                 .max_register = 0xbf,
 116         },
 117         [PAGE1_VDO_BDG] = {
 118                 COMMON_PS8640_REGMAP_CONFIG,
 119                 .max_register = 0xff,
 120         },
 121         [PAGE2_TOP_CNTL] = {
 122                 COMMON_PS8640_REGMAP_CONFIG,
 123                 .max_register = 0xff,
 124         },
 125         [PAGE3_DSI_CNTL1] = {
 126                 COMMON_PS8640_REGMAP_CONFIG,
 127                 .max_register = 0xff,
 128         },
 129         [PAGE4_MIPI_PHY] = {
 130                 COMMON_PS8640_REGMAP_CONFIG,
 131                 .max_register = 0xff,
 132         },
 133         [PAGE5_VPLL] = {
 134                 COMMON_PS8640_REGMAP_CONFIG,
 135                 .max_register = 0x7f,
 136         },
 137         [PAGE6_DSI_CNTL2] = {
 138                 COMMON_PS8640_REGMAP_CONFIG,
 139                 .max_register = 0xff,
 140         },
 141         [PAGE7_SPI_CNTL] = {
 142                 COMMON_PS8640_REGMAP_CONFIG,
 143                 .max_register = 0xff,
 144         },
 145 };
 146
 147 static inline struct ps8640 *bridge_to_ps8640(struct drm_bridge *e)
 148 {
 149         return container_of(e, struct ps8640, bridge);
 150 }
 151
 152 static inline struct ps8640 *aux_to_ps8640(struct drm_dp_aux *aux)
 153 {
 154         return container_of(aux, struct ps8640, aux);
 155 }
 156
 157 static int _ps8640_wait_hpd_asserted(struct ps8640 *ps_bridge, unsigned long wait_us)
 158 {
 159         struct regmap *map = ps_bridge->regmap[PAGE2_TOP_CNTL];
 160         int status;
 161         int ret;
 162
 163         /*
 164          * Apparently something about the firmware in the chip signals that
 165          * HPD goes high by reporting GPIO9 as high (even though HPD isn't
 166          * actually connected to GPIO9).
 167          */
 168         ret = regmap_read_poll_timeout(map, PAGE2_GPIO_H, status,
 169                                        status & PS_GPIO9, 20000, wait_us);
 170
 171         /*
 172          * The first time we see HPD go high after a reset we delay an extra
 173          * 50 ms. The best guess is that the MCU is doing "stuff" during this
 174          * time (maybe talking to the panel) and we don't want to interrupt it.
 175          *
 176          * No locking is done around "need_post_hpd_delay". If we're here we
 177          * know we're holding a PM Runtime reference and the only other place
 178          * that touches this is PM Runtime resume.
 179          */
 180         if (!ret && ps_bridge->need_post_hpd_delay) {
 181                 ps_bridge->need_post_hpd_delay = false;
 182                 msleep(50);
 183         }
 184
 185         return ret;
 186 }
 187
 188 static int ps8640_wait_hpd_asserted(struct drm_dp_aux *aux, unsigned long wait_us)
 189 {
 190         struct ps8640 *ps_bridge = aux_to_ps8640(aux);
 191         struct device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev;
 192         int ret;
 193
 194         /*
 195          * Note that this function is called by code that has already powered
 196          * the panel. We have to power ourselves up but we don't need to worry
 197          * about powering the panel.
 198          */
 199         pm_runtime_get_sync(dev);
 200         ret = _ps8640_wait_hpd_asserted(ps_bridge, wait_us);
 201         pm_runtime_mark_last_busy(dev);
 202         pm_runtime_put_autosuspend(dev);
 203
 204         return ret;
 205 }
 206
 207 static ssize_t ps8640_aux_transfer_msg(struct drm_dp_aux *aux,
 208                                        struct drm_dp_aux_msg *msg)
 209 {
 210         struct ps8640 *ps_bridge = aux_to_ps8640(aux);
 211         struct regmap *map = ps_bridge->regmap[PAGE0_DP_CNTL];
 212         struct device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev;
 213         unsigned int len = msg->size;
 214         unsigned int data;
 215         unsigned int base;
 216         int ret;
 217         u8 request = msg->request &
 218                      ~(DP_AUX_I2C_MOT | DP_AUX_I2C_WRITE_STATUS_UPDATE);
 219         u8 *buf = msg->buffer;
 220         u8 addr_len[PAGE0_SWAUX_LENGTH + 1 - PAGE0_SWAUX_ADDR_7_0];
 221         u8 i;
 222         bool is_native_aux = false;
 223
 224         if (len > DP_AUX_MAX_PAYLOAD_BYTES)
 225                 return -EINVAL;
 226
 227         if (msg->address & ~SWAUX_ADDR_MASK)
 228                 return -EINVAL;
 229
 230         switch (request) {
 231         case DP_AUX_NATIVE_WRITE:
 232         case DP_AUX_NATIVE_READ:
 233                 is_native_aux = true;
 234                 fallthrough;
 235         case DP_AUX_I2C_WRITE:
 236         case DP_AUX_I2C_READ:
 237                 break;
 238         default:
 239                 return -EINVAL;
 240         }
 241
 242         ret = regmap_write(map, PAGE0_AUXCH_CFG3, AUXCH_CFG3_RESET);
 243         if (ret) {
 244                 DRM_DEV_ERROR(dev, "failed to write PAGE0_AUXCH_CFG3: %d\n",
 245                               ret);
 246                 return ret;
 247         }
 248
 249         /* Assume it's good */
 250         msg->reply = 0;
 251
 252         base = PAGE0_SWAUX_ADDR_7_0;
 253         addr_len[PAGE0_SWAUX_ADDR_7_0 - base] = msg->address;
 254         addr_len[PAGE0_SWAUX_ADDR_15_8 - base] = msg->address >> 8;
 255         addr_len[PAGE0_SWAUX_ADDR_23_16 - base] = (msg->address >> 16) |
 256                                                   (msg->request << 4);
 257         addr_len[PAGE0_SWAUX_LENGTH - base] = (len == 0) ? SWAUX_NO_PAYLOAD :
 258                                               ((len - 1) & SWAUX_LENGTH_MASK);
 259
 260         regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
 261                           ARRAY_SIZE(addr_len));
 262
 263         if (len && (request == DP_AUX_NATIVE_WRITE ||
 264                     request == DP_AUX_I2C_WRITE)) {
 265                 /* Write to the internal FIFO buffer */
 266                 for (i = 0; i < len; i++) {
 267                         ret = regmap_write(map, PAGE0_SWAUX_WDATA, buf[i]);
 268                         if (ret) {
 269                                 DRM_DEV_ERROR(dev,
 270                                               "failed to write WDATA: %d\n",
 271                                               ret);
 272                                 return ret;
 273                         }
 274                 }
 275         }
 276
 277         regmap_write(map, PAGE0_SWAUX_CTRL, SWAUX_SEND);
 278
 279         /* Zero delay loop because i2c transactions are slow already */
 280         regmap_read_poll_timeout(map, PAGE0_SWAUX_CTRL, data,
 281                                  !(data & SWAUX_SEND), 0, 50 * 1000);
 282
 283         regmap_read(map, PAGE0_SWAUX_STATUS, &data);
 284         if (ret) {
 285                 DRM_DEV_ERROR(dev, "failed to read PAGE0_SWAUX_STATUS: %d\n",
 286                               ret);
 287                 return ret;
 288         }
 289
 290         switch (data & SWAUX_STATUS_MASK) {
 291         case SWAUX_STATUS_NACK:
 292         case SWAUX_STATUS_I2C_NACK:
 293                 /*
 294                  * The programming guide is not clear about whether a I2C NACK
 295                  * would trigger SWAUX_STATUS_NACK or SWAUX_STATUS_I2C_NACK. So
 296                  * we handle both cases together.
 297                  */
 298                 if (is_native_aux)
 299                         msg->reply |= DP_AUX_NATIVE_REPLY_NACK;
 300                 else
 301                         msg->reply |= DP_AUX_I2C_REPLY_NACK;
 302
 303                 fallthrough;
 304         case SWAUX_STATUS_ACKM:
 305                 len = data & SWAUX_M_MASK;
 306                 break;
 307         case SWAUX_STATUS_DEFER:
 308         case SWAUX_STATUS_I2C_DEFER:
 309                 if (is_native_aux)
 310                         msg->reply |= DP_AUX_NATIVE_REPLY_DEFER;
 311                 else
 312                         msg->reply |= DP_AUX_I2C_REPLY_DEFER;
 313                 len = data & SWAUX_M_MASK;
 314                 break;
 315         case SWAUX_STATUS_INVALID:
 316                 return -EOPNOTSUPP;
 317         case SWAUX_STATUS_TIMEOUT:
 318                 return -ETIMEDOUT;
 319         }
 320
 321         if (len && (request == DP_AUX_NATIVE_READ ||
 322                     request == DP_AUX_I2C_READ)) {
 323                 /* Read from the internal FIFO buffer */
 324                 for (i = 0; i < len; i++) {
 325                         ret = regmap_read(map, PAGE0_SWAUX_RDATA, &data);
 326                         if (ret) {
 327                                 DRM_DEV_ERROR(dev,
 328                                               "failed to read RDATA: %d\n",
 329                                               ret);
 330                                 return ret;
 331                         }
 332
 333                         buf[i] = data;
 334                 }
 335         }
 336
 337         return len;
 338 }
 339
 340 static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux,
 341                                    struct drm_dp_aux_msg *msg)
 342 {
 343         struct ps8640 *ps_bridge = aux_to_ps8640(aux);
 344         struct device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev;
 345         int ret;
 346
 347         pm_runtime_get_sync(dev);
 348         ret = ps8640_aux_transfer_msg(aux, msg);
 349         pm_runtime_mark_last_busy(dev);
 350         pm_runtime_put_autosuspend(dev);
 351
 352         return ret;
 353 }
 354
 355 static void ps8640_bridge_vdo_control(struct ps8640 *ps_bridge,
 356                                       const enum ps8640_vdo_control ctrl)
 357 {
 358         struct regmap *map = ps_bridge->regmap[PAGE3_DSI_CNTL1];
 359         struct device *dev = &ps_bridge->page[PAGE3_DSI_CNTL1]->dev;
 360         u8 vdo_ctrl_buf[] = { VDO_CTL_ADD, ctrl };
 361         int ret;
 362
 363         ret = regmap_bulk_write(map, PAGE3_SET_ADD,
 364                                 vdo_ctrl_buf, sizeof(vdo_ctrl_buf));
 365
 366         if (ret < 0)
 367                 dev_err(dev, "failed to %sable VDO: %d\n",
 368                         ctrl == ENABLE ? "en" : "dis", ret);
 369 }
 370
 371 static int __maybe_unused ps8640_resume(struct device *dev)
 372 {
 373         struct ps8640 *ps_bridge = dev_get_drvdata(dev);
 374         int ret;
 375
 376         ret = regulator_bulk_enable(ARRAY_SIZE(ps_bridge->supplies),
 377                                     ps_bridge->supplies);
 378         if (ret < 0) {
 379                 dev_err(dev, "cannot enable regulators %d\n", ret);
 380                 return ret;
 381         }
 382
 383         gpiod_set_value(ps_bridge->gpio_powerdown, 0);
 384         gpiod_set_value(ps_bridge->gpio_reset, 1);
 385         usleep_range(2000, 2500);
 386         gpiod_set_value(ps_bridge->gpio_reset, 0);
 387         /* Double reset for T4 and T5 */
 388         msleep(50);
 389         gpiod_set_value(ps_bridge->gpio_reset, 1);
 390         msleep(50);
 391         gpiod_set_value(ps_bridge->gpio_reset, 0);
 392
 393         /* We just reset things, so we need a delay after the first HPD */
 394         ps_bridge->need_post_hpd_delay = true;
 395
 396         /*
 397          * Mystery 200 ms delay for the "MCU to be ready". It's unclear if
 398          * this is truly necessary since the MCU will already signal that
 399          * things are "good to go" by signaling HPD on "gpio 9". See
 400          * _ps8640_wait_hpd_asserted(). For now we'll keep this mystery delay
 401          * just in case.
 402          */
 403         msleep(200);
 404
 405         return 0;
 406 }
 407
 408 static int __maybe_unused ps8640_suspend(struct device *dev)
 409 {
 410         struct ps8640 *ps_bridge = dev_get_drvdata(dev);
 411         int ret;
 412
 413         gpiod_set_value(ps_bridge->gpio_reset, 1);
 414         gpiod_set_value(ps_bridge->gpio_powerdown, 1);
 415         ret = regulator_bulk_disable(ARRAY_SIZE(ps_bridge->supplies),
 416                                      ps_bridge->supplies);
 417         if (ret < 0)
 418                 dev_err(dev, "cannot disable regulators %d\n", ret);
 419
 420         return ret;
 421 }
 422
 423 static const struct dev_pm_ops ps8640_pm_ops = {
 424         SET_RUNTIME_PM_OPS(ps8640_suspend, ps8640_resume, NULL)
 425         SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 426                                 pm_runtime_force_resume)
 427 };
 428
 429 static void ps8640_atomic_pre_enable(struct drm_bridge *bridge,
 430                                      struct drm_bridge_state *old_bridge_state)
 431 {
 432         struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
 433         struct regmap *map = ps_bridge->regmap[PAGE2_TOP_CNTL];
 434         struct device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev;
 435         int ret;
 436
 437         pm_runtime_get_sync(dev);
 438         ret = _ps8640_wait_hpd_asserted(ps_bridge, 200 * 1000);
 439         if (ret < 0)
 440                 dev_warn(dev, "HPD didn't go high: %d\n", ret);
 441
 442         /*
 443          * The Manufacturer Command Set (MCS) is a device dependent interface
 444          * intended for factory programming of the display module default
 445          * parameters. Once the display module is configured, the MCS shall be
 446          * disabled by the manufacturer. Once disabled, all MCS commands are
 447          * ignored by the display interface.
 448          */
 449
 450         ret = regmap_update_bits(map, PAGE2_MCS_EN, MCS_EN, 0);
 451         if (ret < 0)
 452                 dev_warn(dev, "failed write PAGE2_MCS_EN: %d\n", ret);
 453
 454         /* Switch access edp panel's edid through i2c */
 455         ret = regmap_write(map, PAGE2_I2C_BYPASS, I2C_BYPASS_EN);
 456         if (ret < 0)
 457                 dev_warn(dev, "failed write PAGE2_MCS_EN: %d\n", ret);
 458
 459         ps8640_bridge_vdo_control(ps_bridge, ENABLE);
 460
 461         ps_bridge->pre_enabled = true;
 462 }
 463
 464 static void ps8640_atomic_post_disable(struct drm_bridge *bridge,
 465                                        struct drm_bridge_state *old_bridge_state)
 466 {
 467         struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
 468
 469         ps_bridge->pre_enabled = false;
 470
 471         ps8640_bridge_vdo_control(ps_bridge, DISABLE);
 472         pm_runtime_put_sync_suspend(&ps_bridge->page[PAGE0_DP_CNTL]->dev);
 473 }
 474
 475 static int ps8640_bridge_attach(struct drm_bridge *bridge,
 476                                 enum drm_bridge_attach_flags flags)
 477 {
 478         struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
 479         struct device *dev = &ps_bridge->page[0]->dev;
 480         int ret;
 481
 482         if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
 483                 return -EINVAL;
 484
 485         ps_bridge->aux.drm_dev = bridge->dev;
 486         ret = drm_dp_aux_register(&ps_bridge->aux);
 487         if (ret) {
 488                 dev_err(dev, "failed to register DP AUX channel: %d\n", ret);
 489                 return ret;
 490         }
 491
 492         ps_bridge->link = device_link_add(bridge->dev->dev, dev, DL_FLAG_STATELESS);
 493         if (!ps_bridge->link) {
 494                 dev_err(dev, "failed to create device link");
 495                 ret = -EINVAL;
 496                 goto err_devlink;
 497         }
 498
 499         /* Attach the panel-bridge to the dsi bridge */
 500         ret = drm_bridge_attach(bridge->encoder, ps_bridge->panel_bridge,
 501                                 &ps_bridge->bridge, flags);
 502         if (ret)
 503                 goto err_bridge_attach;
 504
 505         return 0;
 506
 507 err_bridge_attach:
 508         device_link_del(ps_bridge->link);
 509 err_devlink:
 510         drm_dp_aux_unregister(&ps_bridge->aux);
 511
 512         return ret;
 513 }
 514
 515 static void ps8640_bridge_detach(struct drm_bridge *bridge)
 516 {
 517         struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
 518
 519         drm_dp_aux_unregister(&ps_bridge->aux);
 520         if (ps_bridge->link)
 521                 device_link_del(ps_bridge->link);
 522 }
 523
 524 static void ps8640_runtime_disable(void *data)
 525 {
 526         pm_runtime_dont_use_autosuspend(data);
 527         pm_runtime_disable(data);
 528 }
 529
 530 static const struct drm_bridge_funcs ps8640_bridge_funcs = {
 531         .attach = ps8640_bridge_attach,
 532         .detach = ps8640_bridge_detach,
 533         .atomic_post_disable = ps8640_atomic_post_disable,
 534         .atomic_pre_enable = ps8640_atomic_pre_enable,
 535         .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
 536         .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
 537         .atomic_reset = drm_atomic_helper_bridge_reset,
 538 };
 539
 540 static int ps8640_bridge_get_dsi_resources(struct device *dev, struct ps8640 *ps_bridge)
 541 {
 542         struct device_node *in_ep, *dsi_node;
 543         struct mipi_dsi_device *dsi;
 544         struct mipi_dsi_host *host;
 545         const struct mipi_dsi_device_info info = { .type = "ps8640",
 546                                                    .channel = 0,
 547                                                    .node = NULL,
 548                                                  };
 549
 550         /* port@0 is ps8640 dsi input port */
 551         in_ep = of_graph_get_endpoint_by_regs(dev->of_node, 0, -1);
 552         if (!in_ep)
 553                 return -ENODEV;
 554
 555         dsi_node = of_graph_get_remote_port_parent(in_ep);
 556         of_node_put(in_ep);
 557         if (!dsi_node)
 558                 return -ENODEV;
 559
 560         host = of_find_mipi_dsi_host_by_node(dsi_node);
 561         of_node_put(dsi_node);
 562         if (!host)
 563                 return -EPROBE_DEFER;
 564
 565         dsi = devm_mipi_dsi_device_register_full(dev, host, &info);
 566         if (IS_ERR(dsi)) {
 567                 dev_err(dev, "failed to create dsi device\n");
 568                 return PTR_ERR(dsi);
 569         }
 570
 571         ps_bridge->dsi = dsi;
 572
 573         dsi->host = host;
 574         dsi->mode_flags = MIPI_DSI_MODE_VIDEO |
 575                           MIPI_DSI_MODE_VIDEO_SYNC_PULSE;
 576         dsi->format = MIPI_DSI_FMT_RGB888;
 577         dsi->lanes = NUM_MIPI_LANES;
 578
 579         return 0;
 580 }
 581
 582 static int ps8640_bridge_link_panel(struct drm_dp_aux *aux)
 583 {
 584         struct ps8640 *ps_bridge = aux_to_ps8640(aux);
 585         struct device *dev = aux->dev;
 586         struct device_node *np = dev->of_node;
 587         int ret;
 588
 589         /*
 590          * NOTE about returning -EPROBE_DEFER from this function: if we
 591          * return an error (most relevant to -EPROBE_DEFER) it will only
 592          * be passed out to ps8640_probe() if it called this directly (AKA the
 593          * panel isn't under the "aux-bus" node). That should be fine because
 594          * if the panel is under "aux-bus" it's guaranteed to have probed by
 595          * the time this function has been called.
 596          */
 597
 598         /* port@1 is ps8640 output port */
 599         ps_bridge->panel_bridge = devm_drm_of_get_bridge(dev, np, 1, 0);
 600         if (IS_ERR(ps_bridge->panel_bridge))
 601                 return PTR_ERR(ps_bridge->panel_bridge);
 602
 603         ret = devm_drm_bridge_add(dev, &ps_bridge->bridge);
 604         if (ret)
 605                 return ret;
 606
 607         return devm_mipi_dsi_attach(dev, ps_bridge->dsi);
 608 }
 609
 610 static int ps8640_probe(struct i2c_client *client)
 611 {
 612         struct device *dev = &client->dev;
 613         struct ps8640 *ps_bridge;
 614         int ret;
 615         u32 i;
 616
 617         ps_bridge = devm_kzalloc(dev, sizeof(*ps_bridge), GFP_KERNEL);
 618         if (!ps_bridge)
 619                 return -ENOMEM;
 620
 621         ps_bridge->supplies[0].supply = "vdd12";
 622         ps_bridge->supplies[1].supply = "vdd33";
 623         ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ps_bridge->supplies),
 624                                       ps_bridge->supplies);
 625         if (ret)
 626                 return ret;
 627
 628         ps_bridge->gpio_powerdown = devm_gpiod_get(&client->dev, "powerdown",
 629                                                    GPIOD_OUT_HIGH);
 630         if (IS_ERR(ps_bridge->gpio_powerdown))
 631                 return PTR_ERR(ps_bridge->gpio_powerdown);
 632
 633         /*
 634          * Assert the reset to avoid the bridge being initialized prematurely
 635          */
 636         ps_bridge->gpio_reset = devm_gpiod_get(&client->dev, "reset",
 637                                                GPIOD_OUT_HIGH);
 638         if (IS_ERR(ps_bridge->gpio_reset))
 639                 return PTR_ERR(ps_bridge->gpio_reset);
 640
 641         ps_bridge->bridge.funcs = &ps8640_bridge_funcs;
 642         ps_bridge->bridge.of_node = dev->of_node;
 643         ps_bridge->bridge.type = DRM_MODE_CONNECTOR_eDP;
 644
 645         /*
 646          * Get MIPI DSI resources early. These can return -EPROBE_DEFER so
 647          * we want to get them out of the way sooner.
 648          */
 649         ret = ps8640_bridge_get_dsi_resources(&client->dev, ps_bridge);
 650         if (ret)
 651                 return ret;
 652
 653         ps_bridge->page[PAGE0_DP_CNTL] = client;
 654
 655         ps_bridge->regmap[PAGE0_DP_CNTL] = devm_regmap_init_i2c(client, ps8640_regmap_config);
 656         if (IS_ERR(ps_bridge->regmap[PAGE0_DP_CNTL]))
 657                 return PTR_ERR(ps_bridge->regmap[PAGE0_DP_CNTL]);
 658
 659         for (i = 1; i < ARRAY_SIZE(ps_bridge->page); i++) {
 660                 ps_bridge->page[i] = devm_i2c_new_dummy_device(&client->dev,
 661                                                              client->adapter,
 662                                                              client->addr + i);
 663                 if (IS_ERR(ps_bridge->page[i]))
 664                         return PTR_ERR(ps_bridge->page[i]);
 665
 666                 ps_bridge->regmap[i] = devm_regmap_init_i2c(ps_bridge->page[i],
 667                                                             ps8640_regmap_config + i);
 668                 if (IS_ERR(ps_bridge->regmap[i]))
 669                         return PTR_ERR(ps_bridge->regmap[i]);
 670         }
 671
 672         i2c_set_clientdata(client, ps_bridge);
 673
 674         ps_bridge->aux.name = "parade-ps8640-aux";
 675         ps_bridge->aux.dev = dev;
 676         ps_bridge->aux.transfer = ps8640_aux_transfer;
 677         ps_bridge->aux.wait_hpd_asserted = ps8640_wait_hpd_asserted;
 678         drm_dp_aux_init(&ps_bridge->aux);
 679
 680         pm_runtime_enable(dev);
 681         /*
 682          * Powering on ps8640 takes ~300ms. To avoid wasting time on power
 683          * cycling ps8640 too often, set autosuspend_delay to 2000ms to ensure
 684          * the bridge wouldn't suspend in between each _aux_transfer_msg() call
 685          * during EDID read (~20ms in my experiment) and in between the last
 686          * _aux_transfer_msg() call during EDID read and the _pre_enable() call
 687          * (~100ms in my experiment).
 688          */
 689         pm_runtime_set_autosuspend_delay(dev, 2000);
 690         pm_runtime_use_autosuspend(dev);
 691         pm_suspend_ignore_children(dev, true);
 692         ret = devm_add_action_or_reset(dev, ps8640_runtime_disable, dev);
 693         if (ret)
 694                 return ret;
 695
 696         ret = devm_of_dp_aux_populate_bus(&ps_bridge->aux, ps8640_bridge_link_panel);
 697
 698         /*
 699          * If devm_of_dp_aux_populate_bus() returns -ENODEV then it's up to
 700          * usa to call ps8640_bridge_link_panel() directly. NOTE: in this case
 701          * the function is allowed to -EPROBE_DEFER.
 702          */
 703         if (ret == -ENODEV)
 704                 return ps8640_bridge_link_panel(&ps_bridge->aux);
 705
 706         return ret;
 707 }
 708
 709 static const struct of_device_id ps8640_match[] = {
 710         { .compatible = "parade,ps8640" },
 711         { }
 712 };
 713 MODULE_DEVICE_TABLE(of, ps8640_match);
 714
 715 static struct i2c_driver ps8640_driver = {
 716         .probe = ps8640_probe,
 717         .driver = {
 718                 .name = "ps8640",
 719                 .of_match_table = ps8640_match,
 720                 .pm = &ps8640_pm_ops,
 721         },
 722 };
 723 module_i2c_driver(ps8640_driver);
 724
 725 MODULE_AUTHOR("Jitao Shi <jitao.shi@mediatek.com>");
 726 MODULE_AUTHOR("CK Hu <ck.hu@mediatek.com>");
 727 MODULE_AUTHOR("Enric Balletbo i Serra <enric.balletbo@collabora.com>");
 728 MODULE_DESCRIPTION("PARADE ps8640 DSI-eDP converter driver");
 729 MODULE_LICENSE("GPL v2");