drivers/gpu/drm/exynos/exynos_dp_core.c

   1 /*
   2  * Samsung SoC DP (Display Port) interface driver.
   3  *
   4  * Copyright (C) 2012 Samsung Electronics Co., Ltd.
   5  * Author: Jingoo Han <jg1.han@samsung.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2 of the License, or (at your
  10  * option) any later version.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/err.h>
  16 #include <linux/clk.h>
  17 #include <linux/io.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/of.h>
  20 #include <linux/of_gpio.h>
  21 #include <linux/of_graph.h>
  22 #include <linux/gpio.h>
  23 #include <linux/component.h>
  24 #include <linux/phy/phy.h>
  25 #include <video/of_display_timing.h>
  26 #include <video/of_videomode.h>
  27
  28 #include <drm/drmP.h>
  29 #include <drm/drm_crtc.h>
  30 #include <drm/drm_crtc_helper.h>
  31 #include <drm/drm_atomic_helper.h>
  32 #include <drm/drm_panel.h>
  33
  34 #include "exynos_dp_core.h"
  35 #include "exynos_drm_crtc.h"
  36
  37 #define ctx_from_connector(c)   container_of(c, struct exynos_dp_device, \
  38                                         connector)
  39
  40 static inline struct exynos_drm_crtc *dp_to_crtc(struct exynos_dp_device *dp)
  41 {
  42         return to_exynos_crtc(dp->encoder.crtc);
  43 }
  44
  45 static inline struct exynos_dp_device *encoder_to_dp(
  46                                                 struct drm_encoder *e)
  47 {
  48         return container_of(e, struct exynos_dp_device, encoder);
  49 }
  50
  51 struct bridge_init {
  52         struct i2c_client *client;
  53         struct device_node *node;
  54 };
  55
  56 static void exynos_dp_init_dp(struct exynos_dp_device *dp)
  57 {
  58         exynos_dp_reset(dp);
  59
  60         exynos_dp_swreset(dp);
  61
  62         exynos_dp_init_analog_param(dp);
  63         exynos_dp_init_interrupt(dp);
  64
  65         /* SW defined function Normal operation */
  66         exynos_dp_enable_sw_function(dp);
  67
  68         exynos_dp_config_interrupt(dp);
  69         exynos_dp_init_analog_func(dp);
  70
  71         exynos_dp_init_hpd(dp);
  72         exynos_dp_init_aux(dp);
  73 }
  74
  75 static int exynos_dp_detect_hpd(struct exynos_dp_device *dp)
  76 {
  77         int timeout_loop = 0;
  78
  79         while (exynos_dp_get_plug_in_status(dp) != 0) {
  80                 timeout_loop++;
  81                 if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
  82                         dev_err(dp->dev, "failed to get hpd plug status\n");
  83                         return -ETIMEDOUT;
  84                 }
  85                 usleep_range(10, 11);
  86         }
  87
  88         return 0;
  89 }
  90
  91 static unsigned char exynos_dp_calc_edid_check_sum(unsigned char *edid_data)
  92 {
  93         int i;
  94         unsigned char sum = 0;
  95
  96         for (i = 0; i < EDID_BLOCK_LENGTH; i++)
  97                 sum = sum + edid_data[i];
  98
  99         return sum;
 100 }
 101
 102 static int exynos_dp_read_edid(struct exynos_dp_device *dp)
 103 {
 104         unsigned char edid[EDID_BLOCK_LENGTH * 2];
 105         unsigned int extend_block = 0;
 106         unsigned char sum;
 107         unsigned char test_vector;
 108         int retval;
 109
 110         /*
 111          * EDID device address is 0x50.
 112          * However, if necessary, you must have set upper address
 113          * into E-EDID in I2C device, 0x30.
 114          */
 115
 116         /* Read Extension Flag, Number of 128-byte EDID extension blocks */
 117         retval = exynos_dp_read_byte_from_i2c(dp, I2C_EDID_DEVICE_ADDR,
 118                                 EDID_EXTENSION_FLAG,
 119                                 &extend_block);
 120         if (retval)
 121                 return retval;
 122
 123         if (extend_block > 0) {
 124                 dev_dbg(dp->dev, "EDID data includes a single extension!\n");
 125
 126                 /* Read EDID data */
 127                 retval = exynos_dp_read_bytes_from_i2c(dp, I2C_EDID_DEVICE_ADDR,
 128                                                 EDID_HEADER_PATTERN,
 129                                                 EDID_BLOCK_LENGTH,
 130                                                 &edid[EDID_HEADER_PATTERN]);
 131                 if (retval != 0) {
 132                         dev_err(dp->dev, "EDID Read failed!\n");
 133                         return -EIO;
 134                 }
 135                 sum = exynos_dp_calc_edid_check_sum(edid);
 136                 if (sum != 0) {
 137                         dev_err(dp->dev, "EDID bad checksum!\n");
 138                         return -EIO;
 139                 }
 140
 141                 /* Read additional EDID data */
 142                 retval = exynos_dp_read_bytes_from_i2c(dp,
 143                                 I2C_EDID_DEVICE_ADDR,
 144                                 EDID_BLOCK_LENGTH,
 145                                 EDID_BLOCK_LENGTH,
 146                                 &edid[EDID_BLOCK_LENGTH]);
 147                 if (retval != 0) {
 148                         dev_err(dp->dev, "EDID Read failed!\n");
 149                         return -EIO;
 150                 }
 151                 sum = exynos_dp_calc_edid_check_sum(&edid[EDID_BLOCK_LENGTH]);
 152                 if (sum != 0) {
 153                         dev_err(dp->dev, "EDID bad checksum!\n");
 154                         return -EIO;
 155                 }
 156
 157                 exynos_dp_read_byte_from_dpcd(dp, DP_TEST_REQUEST,
 158                                         &test_vector);
 159                 if (test_vector & DP_TEST_LINK_EDID_READ) {
 160                         exynos_dp_write_byte_to_dpcd(dp,
 161                                 DP_TEST_EDID_CHECKSUM,
 162                                 edid[EDID_BLOCK_LENGTH + EDID_CHECKSUM]);
 163                         exynos_dp_write_byte_to_dpcd(dp,
 164                                 DP_TEST_RESPONSE,
 165                                 DP_TEST_EDID_CHECKSUM_WRITE);
 166                 }
 167         } else {
 168                 dev_info(dp->dev, "EDID data does not include any extensions.\n");
 169
 170                 /* Read EDID data */
 171                 retval = exynos_dp_read_bytes_from_i2c(dp,
 172                                 I2C_EDID_DEVICE_ADDR,
 173                                 EDID_HEADER_PATTERN,
 174                                 EDID_BLOCK_LENGTH,
 175                                 &edid[EDID_HEADER_PATTERN]);
 176                 if (retval != 0) {
 177                         dev_err(dp->dev, "EDID Read failed!\n");
 178                         return -EIO;
 179                 }
 180                 sum = exynos_dp_calc_edid_check_sum(edid);
 181                 if (sum != 0) {
 182                         dev_err(dp->dev, "EDID bad checksum!\n");
 183                         return -EIO;
 184                 }
 185
 186                 exynos_dp_read_byte_from_dpcd(dp,
 187                         DP_TEST_REQUEST,
 188                         &test_vector);
 189                 if (test_vector & DP_TEST_LINK_EDID_READ) {
 190                         exynos_dp_write_byte_to_dpcd(dp,
 191                                 DP_TEST_EDID_CHECKSUM,
 192                                 edid[EDID_CHECKSUM]);
 193                         exynos_dp_write_byte_to_dpcd(dp,
 194                                 DP_TEST_RESPONSE,
 195                                 DP_TEST_EDID_CHECKSUM_WRITE);
 196                 }
 197         }
 198
 199         dev_dbg(dp->dev, "EDID Read success!\n");
 200         return 0;
 201 }
 202
 203 static int exynos_dp_handle_edid(struct exynos_dp_device *dp)
 204 {
 205         u8 buf[12];
 206         int i;
 207         int retval;
 208
 209         /* Read DPCD DP_DPCD_REV~RECEIVE_PORT1_CAP_1 */
 210         retval = exynos_dp_read_bytes_from_dpcd(dp, DP_DPCD_REV,
 211                                 12, buf);
 212         if (retval)
 213                 return retval;
 214
 215         /* Read EDID */
 216         for (i = 0; i < 3; i++) {
 217                 retval = exynos_dp_read_edid(dp);
 218                 if (!retval)
 219                         break;
 220         }
 221
 222         return retval;
 223 }
 224
 225 static void exynos_dp_enable_rx_to_enhanced_mode(struct exynos_dp_device *dp,
 226                                                 bool enable)
 227 {
 228         u8 data;
 229
 230         exynos_dp_read_byte_from_dpcd(dp, DP_LANE_COUNT_SET, &data);
 231
 232         if (enable)
 233                 exynos_dp_write_byte_to_dpcd(dp, DP_LANE_COUNT_SET,
 234                         DP_LANE_COUNT_ENHANCED_FRAME_EN |
 235                         DPCD_LANE_COUNT_SET(data));
 236         else
 237                 exynos_dp_write_byte_to_dpcd(dp, DP_LANE_COUNT_SET,
 238                         DPCD_LANE_COUNT_SET(data));
 239 }
 240
 241 static int exynos_dp_is_enhanced_mode_available(struct exynos_dp_device *dp)
 242 {
 243         u8 data;
 244         int retval;
 245
 246         exynos_dp_read_byte_from_dpcd(dp, DP_MAX_LANE_COUNT, &data);
 247         retval = DPCD_ENHANCED_FRAME_CAP(data);
 248
 249         return retval;
 250 }
 251
 252 static void exynos_dp_set_enhanced_mode(struct exynos_dp_device *dp)
 253 {
 254         u8 data;
 255
 256         data = exynos_dp_is_enhanced_mode_available(dp);
 257         exynos_dp_enable_rx_to_enhanced_mode(dp, data);
 258         exynos_dp_enable_enhanced_mode(dp, data);
 259 }
 260
 261 static void exynos_dp_training_pattern_dis(struct exynos_dp_device *dp)
 262 {
 263         exynos_dp_set_training_pattern(dp, DP_NONE);
 264
 265         exynos_dp_write_byte_to_dpcd(dp,
 266                 DP_TRAINING_PATTERN_SET,
 267                 DP_TRAINING_PATTERN_DISABLE);
 268 }
 269
 270 static void exynos_dp_set_lane_lane_pre_emphasis(struct exynos_dp_device *dp,
 271                                         int pre_emphasis, int lane)
 272 {
 273         switch (lane) {
 274         case 0:
 275                 exynos_dp_set_lane0_pre_emphasis(dp, pre_emphasis);
 276                 break;
 277         case 1:
 278                 exynos_dp_set_lane1_pre_emphasis(dp, pre_emphasis);
 279                 break;
 280
 281         case 2:
 282                 exynos_dp_set_lane2_pre_emphasis(dp, pre_emphasis);
 283                 break;
 284
 285         case 3:
 286                 exynos_dp_set_lane3_pre_emphasis(dp, pre_emphasis);
 287                 break;
 288         }
 289 }
 290
 291 static int exynos_dp_link_start(struct exynos_dp_device *dp)
 292 {
 293         u8 buf[4];
 294         int lane, lane_count, pll_tries, retval;
 295
 296         lane_count = dp->link_train.lane_count;
 297
 298         dp->link_train.lt_state = CLOCK_RECOVERY;
 299         dp->link_train.eq_loop = 0;
 300
 301         for (lane = 0; lane < lane_count; lane++)
 302                 dp->link_train.cr_loop[lane] = 0;
 303
 304         /* Set link rate and count as you want to establish*/
 305         exynos_dp_set_link_bandwidth(dp, dp->link_train.link_rate);
 306         exynos_dp_set_lane_count(dp, dp->link_train.lane_count);
 307
 308         /* Setup RX configuration */
 309         buf[0] = dp->link_train.link_rate;
 310         buf[1] = dp->link_train.lane_count;
 311         retval = exynos_dp_write_bytes_to_dpcd(dp, DP_LINK_BW_SET,
 312                                 2, buf);
 313         if (retval)
 314                 return retval;
 315
 316         /* Set TX pre-emphasis to minimum */
 317         for (lane = 0; lane < lane_count; lane++)
 318                 exynos_dp_set_lane_lane_pre_emphasis(dp,
 319                         PRE_EMPHASIS_LEVEL_0, lane);
 320
 321         /* Wait for PLL lock */
 322         pll_tries = 0;
 323         while (exynos_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
 324                 if (pll_tries == DP_TIMEOUT_LOOP_COUNT) {
 325                         dev_err(dp->dev, "Wait for PLL lock timed out\n");
 326                         return -ETIMEDOUT;
 327                 }
 328
 329                 pll_tries++;
 330                 usleep_range(90, 120);
 331         }
 332
 333         /* Set training pattern 1 */
 334         exynos_dp_set_training_pattern(dp, TRAINING_PTN1);
 335
 336         /* Set RX training pattern */
 337         retval = exynos_dp_write_byte_to_dpcd(dp,
 338                         DP_TRAINING_PATTERN_SET,
 339                         DP_LINK_SCRAMBLING_DISABLE | DP_TRAINING_PATTERN_1);
 340         if (retval)
 341                 return retval;
 342
 343         for (lane = 0; lane < lane_count; lane++)
 344                 buf[lane] = DP_TRAIN_PRE_EMPH_LEVEL_0 |
 345                             DP_TRAIN_VOLTAGE_SWING_LEVEL_0;
 346
 347         retval = exynos_dp_write_bytes_to_dpcd(dp, DP_TRAINING_LANE0_SET,
 348                         lane_count, buf);
 349
 350         return retval;
 351 }
 352
 353 static unsigned char exynos_dp_get_lane_status(u8 link_status[2], int lane)
 354 {
 355         int shift = (lane & 1) * 4;
 356         u8 link_value = link_status[lane>>1];
 357
 358         return (link_value >> shift) & 0xf;
 359 }
 360
 361 static int exynos_dp_clock_recovery_ok(u8 link_status[2], int lane_count)
 362 {
 363         int lane;
 364         u8 lane_status;
 365
 366         for (lane = 0; lane < lane_count; lane++) {
 367                 lane_status = exynos_dp_get_lane_status(link_status, lane);
 368                 if ((lane_status & DP_LANE_CR_DONE) == 0)
 369                         return -EINVAL;
 370         }
 371         return 0;
 372 }
 373
 374 static int exynos_dp_channel_eq_ok(u8 link_status[2], u8 link_align,
 375                                 int lane_count)
 376 {
 377         int lane;
 378         u8 lane_status;
 379
 380         if ((link_align & DP_INTERLANE_ALIGN_DONE) == 0)
 381                 return -EINVAL;
 382
 383         for (lane = 0; lane < lane_count; lane++) {
 384                 lane_status = exynos_dp_get_lane_status(link_status, lane);
 385                 lane_status &= DP_CHANNEL_EQ_BITS;
 386                 if (lane_status != DP_CHANNEL_EQ_BITS)
 387                         return -EINVAL;
 388         }
 389
 390         return 0;
 391 }
 392
 393 static unsigned char exynos_dp_get_adjust_request_voltage(u8 adjust_request[2],
 394                                                         int lane)
 395 {
 396         int shift = (lane & 1) * 4;
 397         u8 link_value = adjust_request[lane>>1];
 398
 399         return (link_value >> shift) & 0x3;
 400 }
 401
 402 static unsigned char exynos_dp_get_adjust_request_pre_emphasis(
 403                                         u8 adjust_request[2],
 404                                         int lane)
 405 {
 406         int shift = (lane & 1) * 4;
 407         u8 link_value = adjust_request[lane>>1];
 408
 409         return ((link_value >> shift) & 0xc) >> 2;
 410 }
 411
 412 static void exynos_dp_set_lane_link_training(struct exynos_dp_device *dp,
 413                                         u8 training_lane_set, int lane)
 414 {
 415         switch (lane) {
 416         case 0:
 417                 exynos_dp_set_lane0_link_training(dp, training_lane_set);
 418                 break;
 419         case 1:
 420                 exynos_dp_set_lane1_link_training(dp, training_lane_set);
 421                 break;
 422
 423         case 2:
 424                 exynos_dp_set_lane2_link_training(dp, training_lane_set);
 425                 break;
 426
 427         case 3:
 428                 exynos_dp_set_lane3_link_training(dp, training_lane_set);
 429                 break;
 430         }
 431 }
 432
 433 static unsigned int exynos_dp_get_lane_link_training(
 434                                 struct exynos_dp_device *dp,
 435                                 int lane)
 436 {
 437         u32 reg;
 438
 439         switch (lane) {
 440         case 0:
 441                 reg = exynos_dp_get_lane0_link_training(dp);
 442                 break;
 443         case 1:
 444                 reg = exynos_dp_get_lane1_link_training(dp);
 445                 break;
 446         case 2:
 447                 reg = exynos_dp_get_lane2_link_training(dp);
 448                 break;
 449         case 3:
 450                 reg = exynos_dp_get_lane3_link_training(dp);
 451                 break;
 452         default:
 453                 WARN_ON(1);
 454                 return 0;
 455         }
 456
 457         return reg;
 458 }
 459
 460 static void exynos_dp_reduce_link_rate(struct exynos_dp_device *dp)
 461 {
 462         exynos_dp_training_pattern_dis(dp);
 463         exynos_dp_set_enhanced_mode(dp);
 464
 465         dp->link_train.lt_state = FAILED;
 466 }
 467
 468 static void exynos_dp_get_adjust_training_lane(struct exynos_dp_device *dp,
 469                                         u8 adjust_request[2])
 470 {
 471         int lane, lane_count;
 472         u8 voltage_swing, pre_emphasis, training_lane;
 473
 474         lane_count = dp->link_train.lane_count;
 475         for (lane = 0; lane < lane_count; lane++) {
 476                 voltage_swing = exynos_dp_get_adjust_request_voltage(
 477                                                 adjust_request, lane);
 478                 pre_emphasis = exynos_dp_get_adjust_request_pre_emphasis(
 479                                                 adjust_request, lane);
 480                 training_lane = DPCD_VOLTAGE_SWING_SET(voltage_swing) |
 481                                 DPCD_PRE_EMPHASIS_SET(pre_emphasis);
 482
 483                 if (voltage_swing == VOLTAGE_LEVEL_3)
 484                         training_lane |= DP_TRAIN_MAX_SWING_REACHED;
 485                 if (pre_emphasis == PRE_EMPHASIS_LEVEL_3)
 486                         training_lane |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
 487
 488                 dp->link_train.training_lane[lane] = training_lane;
 489         }
 490 }
 491
 492 static int exynos_dp_process_clock_recovery(struct exynos_dp_device *dp)
 493 {
 494         int lane, lane_count, retval;
 495         u8 voltage_swing, pre_emphasis, training_lane;
 496         u8 link_status[2], adjust_request[2];
 497
 498         usleep_range(100, 101);
 499
 500         lane_count = dp->link_train.lane_count;
 501
 502         retval =  exynos_dp_read_bytes_from_dpcd(dp,
 503                         DP_LANE0_1_STATUS, 2, link_status);
 504         if (retval)
 505                 return retval;
 506
 507         retval =  exynos_dp_read_bytes_from_dpcd(dp,
 508                         DP_ADJUST_REQUEST_LANE0_1, 2, adjust_request);
 509         if (retval)
 510                 return retval;
 511
 512         if (exynos_dp_clock_recovery_ok(link_status, lane_count) == 0) {
 513                 /* set training pattern 2 for EQ */
 514                 exynos_dp_set_training_pattern(dp, TRAINING_PTN2);
 515
 516                 retval = exynos_dp_write_byte_to_dpcd(dp,
 517                                 DP_TRAINING_PATTERN_SET,
 518                                 DP_LINK_SCRAMBLING_DISABLE |
 519                                 DP_TRAINING_PATTERN_2);
 520                 if (retval)
 521                         return retval;
 522
 523                 dev_info(dp->dev, "Link Training Clock Recovery success\n");
 524                 dp->link_train.lt_state = EQUALIZER_TRAINING;
 525         } else {
 526                 for (lane = 0; lane < lane_count; lane++) {
 527                         training_lane = exynos_dp_get_lane_link_training(
 528                                                         dp, lane);
 529                         voltage_swing = exynos_dp_get_adjust_request_voltage(
 530                                                         adjust_request, lane);
 531                         pre_emphasis = exynos_dp_get_adjust_request_pre_emphasis(
 532                                                         adjust_request, lane);
 533
 534                         if (DPCD_VOLTAGE_SWING_GET(training_lane) ==
 535                                         voltage_swing &&
 536                             DPCD_PRE_EMPHASIS_GET(training_lane) ==
 537                                         pre_emphasis)
 538                                 dp->link_train.cr_loop[lane]++;
 539
 540                         if (dp->link_train.cr_loop[lane] == MAX_CR_LOOP ||
 541                             voltage_swing == VOLTAGE_LEVEL_3 ||
 542                             pre_emphasis == PRE_EMPHASIS_LEVEL_3) {
 543                                 dev_err(dp->dev, "CR Max reached (%d,%d,%d)\n",
 544                                         dp->link_train.cr_loop[lane],
 545                                         voltage_swing, pre_emphasis);
 546                                 exynos_dp_reduce_link_rate(dp);
 547                                 return -EIO;
 548                         }
 549                 }
 550         }
 551
 552         exynos_dp_get_adjust_training_lane(dp, adjust_request);
 553
 554         for (lane = 0; lane < lane_count; lane++)
 555                 exynos_dp_set_lane_link_training(dp,
 556                         dp->link_train.training_lane[lane], lane);
 557
 558         retval = exynos_dp_write_bytes_to_dpcd(dp,
 559                         DP_TRAINING_LANE0_SET, lane_count,
 560                         dp->link_train.training_lane);
 561         if (retval)
 562                 return retval;
 563
 564         return retval;
 565 }
 566
 567 static int exynos_dp_process_equalizer_training(struct exynos_dp_device *dp)
 568 {
 569         int lane, lane_count, retval;
 570         u32 reg;
 571         u8 link_align, link_status[2], adjust_request[2];
 572
 573         usleep_range(400, 401);
 574
 575         lane_count = dp->link_train.lane_count;
 576
 577         retval = exynos_dp_read_bytes_from_dpcd(dp,
 578                         DP_LANE0_1_STATUS, 2, link_status);
 579         if (retval)
 580                 return retval;
 581
 582         if (exynos_dp_clock_recovery_ok(link_status, lane_count)) {
 583                 exynos_dp_reduce_link_rate(dp);
 584                 return -EIO;
 585         }
 586
 587         retval = exynos_dp_read_bytes_from_dpcd(dp,
 588                         DP_ADJUST_REQUEST_LANE0_1, 2, adjust_request);
 589         if (retval)
 590                 return retval;
 591
 592         retval = exynos_dp_read_byte_from_dpcd(dp,
 593                         DP_LANE_ALIGN_STATUS_UPDATED, &link_align);
 594         if (retval)
 595                 return retval;
 596
 597         exynos_dp_get_adjust_training_lane(dp, adjust_request);
 598
 599         if (!exynos_dp_channel_eq_ok(link_status, link_align, lane_count)) {
 600                 /* traing pattern Set to Normal */
 601                 exynos_dp_training_pattern_dis(dp);
 602
 603                 dev_info(dp->dev, "Link Training success!\n");
 604
 605                 exynos_dp_get_link_bandwidth(dp, &reg);
 606                 dp->link_train.link_rate = reg;
 607                 dev_dbg(dp->dev, "final bandwidth = %.2x\n",
 608                         dp->link_train.link_rate);
 609
 610                 exynos_dp_get_lane_count(dp, &reg);
 611                 dp->link_train.lane_count = reg;
 612                 dev_dbg(dp->dev, "final lane count = %.2x\n",
 613                         dp->link_train.lane_count);
 614
 615                 /* set enhanced mode if available */
 616                 exynos_dp_set_enhanced_mode(dp);
 617                 dp->link_train.lt_state = FINISHED;
 618
 619                 return 0;
 620         }
 621
 622         /* not all locked */
 623         dp->link_train.eq_loop++;
 624
 625         if (dp->link_train.eq_loop > MAX_EQ_LOOP) {
 626                 dev_err(dp->dev, "EQ Max loop\n");
 627                 exynos_dp_reduce_link_rate(dp);
 628                 return -EIO;
 629         }
 630
 631         for (lane = 0; lane < lane_count; lane++)
 632                 exynos_dp_set_lane_link_training(dp,
 633                         dp->link_train.training_lane[lane], lane);
 634
 635         retval = exynos_dp_write_bytes_to_dpcd(dp, DP_TRAINING_LANE0_SET,
 636                         lane_count, dp->link_train.training_lane);
 637
 638         return retval;
 639 }
 640
 641 static void exynos_dp_get_max_rx_bandwidth(struct exynos_dp_device *dp,
 642                                         u8 *bandwidth)
 643 {
 644         u8 data;
 645
 646         /*
 647          * For DP rev.1.1, Maximum link rate of Main Link lanes
 648          * 0x06 = 1.62 Gbps, 0x0a = 2.7 Gbps
 649          */
 650         exynos_dp_read_byte_from_dpcd(dp, DP_MAX_LINK_RATE, &data);
 651         *bandwidth = data;
 652 }
 653
 654 static void exynos_dp_get_max_rx_lane_count(struct exynos_dp_device *dp,
 655                                         u8 *lane_count)
 656 {
 657         u8 data;
 658
 659         /*
 660          * For DP rev.1.1, Maximum number of Main Link lanes
 661          * 0x01 = 1 lane, 0x02 = 2 lanes, 0x04 = 4 lanes
 662          */
 663         exynos_dp_read_byte_from_dpcd(dp, DP_MAX_LANE_COUNT, &data);
 664         *lane_count = DPCD_MAX_LANE_COUNT(data);
 665 }
 666
 667 static void exynos_dp_init_training(struct exynos_dp_device *dp,
 668                         enum link_lane_count_type max_lane,
 669                         enum link_rate_type max_rate)
 670 {
 671         /*
 672          * MACRO_RST must be applied after the PLL_LOCK to avoid
 673          * the DP inter pair skew issue for at least 10 us
 674          */
 675         exynos_dp_reset_macro(dp);
 676
 677         /* Initialize by reading RX's DPCD */
 678         exynos_dp_get_max_rx_bandwidth(dp, &dp->link_train.link_rate);
 679         exynos_dp_get_max_rx_lane_count(dp, &dp->link_train.lane_count);
 680
 681         if ((dp->link_train.link_rate != LINK_RATE_1_62GBPS) &&
 682            (dp->link_train.link_rate != LINK_RATE_2_70GBPS)) {
 683                 dev_err(dp->dev, "Rx Max Link Rate is abnormal :%x !\n",
 684                         dp->link_train.link_rate);
 685                 dp->link_train.link_rate = LINK_RATE_1_62GBPS;
 686         }
 687
 688         if (dp->link_train.lane_count == 0) {
 689                 dev_err(dp->dev, "Rx Max Lane count is abnormal :%x !\n",
 690                         dp->link_train.lane_count);
 691                 dp->link_train.lane_count = (u8)LANE_COUNT1;
 692         }
 693
 694         /* Setup TX lane count & rate */
 695         if (dp->link_train.lane_count > max_lane)
 696                 dp->link_train.lane_count = max_lane;
 697         if (dp->link_train.link_rate > max_rate)
 698                 dp->link_train.link_rate = max_rate;
 699
 700         /* All DP analog module power up */
 701         exynos_dp_set_analog_power_down(dp, POWER_ALL, 0);
 702 }
 703
 704 static int exynos_dp_sw_link_training(struct exynos_dp_device *dp)
 705 {
 706         int retval = 0, training_finished = 0;
 707
 708         dp->link_train.lt_state = START;
 709
 710         /* Process here */
 711         while (!retval && !training_finished) {
 712                 switch (dp->link_train.lt_state) {
 713                 case START:
 714                         retval = exynos_dp_link_start(dp);
 715                         if (retval)
 716                                 dev_err(dp->dev, "LT link start failed!\n");
 717                         break;
 718                 case CLOCK_RECOVERY:
 719                         retval = exynos_dp_process_clock_recovery(dp);
 720                         if (retval)
 721                                 dev_err(dp->dev, "LT CR failed!\n");
 722                         break;
 723                 case EQUALIZER_TRAINING:
 724                         retval = exynos_dp_process_equalizer_training(dp);
 725                         if (retval)
 726                                 dev_err(dp->dev, "LT EQ failed!\n");
 727                         break;
 728                 case FINISHED:
 729                         training_finished = 1;
 730                         break;
 731                 case FAILED:
 732                         return -EREMOTEIO;
 733                 }
 734         }
 735         if (retval)
 736                 dev_err(dp->dev, "eDP link training failed (%d)\n", retval);
 737
 738         return retval;
 739 }
 740
 741 static int exynos_dp_set_link_train(struct exynos_dp_device *dp,
 742                                 u32 count,
 743                                 u32 bwtype)
 744 {
 745         int i;
 746         int retval;
 747
 748         for (i = 0; i < DP_TIMEOUT_LOOP_COUNT; i++) {
 749                 exynos_dp_init_training(dp, count, bwtype);
 750                 retval = exynos_dp_sw_link_training(dp);
 751                 if (retval == 0)
 752                         break;
 753
 754                 usleep_range(100, 110);
 755         }
 756
 757         return retval;
 758 }
 759
 760 static int exynos_dp_config_video(struct exynos_dp_device *dp)
 761 {
 762         int retval = 0;
 763         int timeout_loop = 0;
 764         int done_count = 0;
 765
 766         exynos_dp_config_video_slave_mode(dp);
 767
 768         exynos_dp_set_video_color_format(dp);
 769
 770         if (exynos_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
 771                 dev_err(dp->dev, "PLL is not locked yet.\n");
 772                 return -EINVAL;
 773         }
 774
 775         for (;;) {
 776                 timeout_loop++;
 777                 if (exynos_dp_is_slave_video_stream_clock_on(dp) == 0)
 778                         break;
 779                 if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
 780                         dev_err(dp->dev, "Timeout of video streamclk ok\n");
 781                         return -ETIMEDOUT;
 782                 }
 783
 784                 usleep_range(1, 2);
 785         }
 786
 787         /* Set to use the register calculated M/N video */
 788         exynos_dp_set_video_cr_mn(dp, CALCULATED_M, 0, 0);
 789
 790         /* For video bist, Video timing must be generated by register */
 791         exynos_dp_set_video_timing_mode(dp, VIDEO_TIMING_FROM_CAPTURE);
 792
 793         /* Disable video mute */
 794         exynos_dp_enable_video_mute(dp, 0);
 795
 796         /* Configure video slave mode */
 797         exynos_dp_enable_video_master(dp, 0);
 798
 799         timeout_loop = 0;
 800
 801         for (;;) {
 802                 timeout_loop++;
 803                 if (exynos_dp_is_video_stream_on(dp) == 0) {
 804                         done_count++;
 805                         if (done_count > 10)
 806                                 break;
 807                 } else if (done_count) {
 808                         done_count = 0;
 809                 }
 810                 if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
 811                         dev_err(dp->dev, "Timeout of video streamclk ok\n");
 812                         return -ETIMEDOUT;
 813                 }
 814
 815                 usleep_range(1000, 1001);
 816         }
 817
 818         if (retval != 0)
 819                 dev_err(dp->dev, "Video stream is not detected!\n");
 820
 821         return retval;
 822 }
 823
 824 static void exynos_dp_enable_scramble(struct exynos_dp_device *dp, bool enable)
 825 {
 826         u8 data;
 827
 828         if (enable) {
 829                 exynos_dp_enable_scrambling(dp);
 830
 831                 exynos_dp_read_byte_from_dpcd(dp,
 832                         DP_TRAINING_PATTERN_SET,
 833                         &data);
 834                 exynos_dp_write_byte_to_dpcd(dp,
 835                         DP_TRAINING_PATTERN_SET,
 836                         (u8)(data & ~DP_LINK_SCRAMBLING_DISABLE));
 837         } else {
 838                 exynos_dp_disable_scrambling(dp);
 839
 840                 exynos_dp_read_byte_from_dpcd(dp,
 841                         DP_TRAINING_PATTERN_SET,
 842                         &data);
 843                 exynos_dp_write_byte_to_dpcd(dp,
 844                         DP_TRAINING_PATTERN_SET,
 845                         (u8)(data | DP_LINK_SCRAMBLING_DISABLE));
 846         }
 847 }
 848
 849 static irqreturn_t exynos_dp_irq_handler(int irq, void *arg)
 850 {
 851         struct exynos_dp_device *dp = arg;
 852
 853         enum dp_irq_type irq_type;
 854
 855         irq_type = exynos_dp_get_irq_type(dp);
 856         switch (irq_type) {
 857         case DP_IRQ_TYPE_HP_CABLE_IN:
 858                 dev_dbg(dp->dev, "Received irq - cable in\n");
 859                 schedule_work(&dp->hotplug_work);
 860                 exynos_dp_clear_hotplug_interrupts(dp);
 861                 break;
 862         case DP_IRQ_TYPE_HP_CABLE_OUT:
 863                 dev_dbg(dp->dev, "Received irq - cable out\n");
 864                 exynos_dp_clear_hotplug_interrupts(dp);
 865                 break;
 866         case DP_IRQ_TYPE_HP_CHANGE:
 867                 /*
 868                  * We get these change notifications once in a while, but there
 869                  * is nothing we can do with them. Just ignore it for now and
 870                  * only handle cable changes.
 871                  */
 872                 dev_dbg(dp->dev, "Received irq - hotplug change; ignoring.\n");
 873                 exynos_dp_clear_hotplug_interrupts(dp);
 874                 break;
 875         default:
 876                 dev_err(dp->dev, "Received irq - unknown type!\n");
 877                 break;
 878         }
 879         return IRQ_HANDLED;
 880 }
 881
 882 static void exynos_dp_hotplug(struct work_struct *work)
 883 {
 884         struct exynos_dp_device *dp;
 885
 886         dp = container_of(work, struct exynos_dp_device, hotplug_work);
 887
 888         if (dp->drm_dev)
 889                 drm_helper_hpd_irq_event(dp->drm_dev);
 890 }
 891
 892 static void exynos_dp_commit(struct drm_encoder *encoder)
 893 {
 894         struct exynos_dp_device *dp = encoder_to_dp(encoder);
 895         int ret;
 896
 897         /* Keep the panel disabled while we configure video */
 898         if (dp->panel) {
 899                 if (drm_panel_disable(dp->panel))
 900                         DRM_ERROR("failed to disable the panel\n");
 901         }
 902
 903         ret = exynos_dp_detect_hpd(dp);
 904         if (ret) {
 905                 /* Cable has been disconnected, we're done */
 906                 return;
 907         }
 908
 909         ret = exynos_dp_handle_edid(dp);
 910         if (ret) {
 911                 dev_err(dp->dev, "unable to handle edid\n");
 912                 return;
 913         }
 914
 915         ret = exynos_dp_set_link_train(dp, dp->video_info->lane_count,
 916                                         dp->video_info->link_rate);
 917         if (ret) {
 918                 dev_err(dp->dev, "unable to do link train\n");
 919                 return;
 920         }
 921
 922         exynos_dp_enable_scramble(dp, 1);
 923         exynos_dp_enable_rx_to_enhanced_mode(dp, 1);
 924         exynos_dp_enable_enhanced_mode(dp, 1);
 925
 926         exynos_dp_set_lane_count(dp, dp->video_info->lane_count);
 927         exynos_dp_set_link_bandwidth(dp, dp->video_info->link_rate);
 928
 929         exynos_dp_init_video(dp);
 930         ret = exynos_dp_config_video(dp);
 931         if (ret)
 932                 dev_err(dp->dev, "unable to config video\n");
 933
 934         /* Safe to enable the panel now */
 935         if (dp->panel) {
 936                 if (drm_panel_enable(dp->panel))
 937                         DRM_ERROR("failed to enable the panel\n");
 938         }
 939
 940         /* Enable video */
 941         exynos_dp_start_video(dp);
 942 }
 943
 944 static enum drm_connector_status exynos_dp_detect(
 945                                 struct drm_connector *connector, bool force)
 946 {
 947         return connector_status_connected;
 948 }
 949
 950 static void exynos_dp_connector_destroy(struct drm_connector *connector)
 951 {
 952         drm_connector_unregister(connector);
 953         drm_connector_cleanup(connector);
 954 }
 955
 956 static const struct drm_connector_funcs exynos_dp_connector_funcs = {
 957         .dpms = drm_atomic_helper_connector_dpms,
 958         .fill_modes = drm_helper_probe_single_connector_modes,
 959         .detect = exynos_dp_detect,
 960         .destroy = exynos_dp_connector_destroy,
 961         .reset = drm_atomic_helper_connector_reset,
 962         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 963         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 964 };
 965
 966 static int exynos_dp_get_modes(struct drm_connector *connector)
 967 {
 968         struct exynos_dp_device *dp = ctx_from_connector(connector);
 969         struct drm_display_mode *mode;
 970
 971         if (dp->panel)
 972                 return drm_panel_get_modes(dp->panel);
 973
 974         mode = drm_mode_create(connector->dev);
 975         if (!mode) {
 976                 DRM_ERROR("failed to create a new display mode.\n");
 977                 return 0;
 978         }
 979
 980         drm_display_mode_from_videomode(&dp->vm, mode);
 981         connector->display_info.width_mm = mode->width_mm;
 982         connector->display_info.height_mm = mode->height_mm;
 983
 984         mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
 985         drm_mode_set_name(mode);
 986         drm_mode_probed_add(connector, mode);
 987
 988         return 1;
 989 }
 990
 991 static struct drm_encoder *exynos_dp_best_encoder(
 992                         struct drm_connector *connector)
 993 {
 994         struct exynos_dp_device *dp = ctx_from_connector(connector);
 995
 996         return &dp->encoder;
 997 }
 998
 999 static const struct drm_connector_helper_funcs exynos_dp_connector_helper_funcs = {
1000         .get_modes = exynos_dp_get_modes,
1001         .best_encoder = exynos_dp_best_encoder,
1002 };
1003
1004 /* returns the number of bridges attached */
1005 static int exynos_drm_attach_lcd_bridge(struct exynos_dp_device *dp,
1006                 struct drm_encoder *encoder)
1007 {
1008         int ret;
1009
1010         encoder->bridge->next = dp->ptn_bridge;
1011         dp->ptn_bridge->encoder = encoder;
1012         ret = drm_bridge_attach(encoder->dev, dp->ptn_bridge);
1013         if (ret) {
1014                 DRM_ERROR("Failed to attach bridge to drm\n");
1015                 return ret;
1016         }
1017
1018         return 0;
1019 }
1020
1021 static int exynos_dp_bridge_attach(struct drm_bridge *bridge)
1022 {
1023         struct exynos_dp_device *dp = bridge->driver_private;
1024         struct drm_encoder *encoder = &dp->encoder;
1025         struct drm_connector *connector = &dp->connector;
1026         int ret;
1027
1028         /* Pre-empt DP connector creation if there's a bridge */
1029         if (dp->ptn_bridge) {
1030                 ret = exynos_drm_attach_lcd_bridge(dp, encoder);
1031                 if (!ret)
1032                         return 0;
1033         }
1034
1035         connector->polled = DRM_CONNECTOR_POLL_HPD;
1036
1037         ret = drm_connector_init(dp->drm_dev, connector,
1038                         &exynos_dp_connector_funcs, DRM_MODE_CONNECTOR_eDP);
1039         if (ret) {
1040                 DRM_ERROR("Failed to initialize connector with drm\n");
1041                 return ret;
1042         }
1043
1044         drm_connector_helper_add(connector, &exynos_dp_connector_helper_funcs);
1045         drm_connector_register(connector);
1046         drm_mode_connector_attach_encoder(connector, encoder);
1047
1048         if (dp->panel)
1049                 ret = drm_panel_attach(dp->panel, &dp->connector);
1050
1051         return ret;
1052 }
1053
1054 static void exynos_dp_bridge_enable(struct drm_bridge *bridge)
1055 {
1056         struct exynos_dp_device *dp = bridge->driver_private;
1057         struct exynos_drm_crtc *crtc = dp_to_crtc(dp);
1058
1059         if (dp->dpms_mode == DRM_MODE_DPMS_ON)
1060                 return;
1061
1062         pm_runtime_get_sync(dp->dev);
1063
1064         if (dp->panel) {
1065                 if (drm_panel_prepare(dp->panel)) {
1066                         DRM_ERROR("failed to setup the panel\n");
1067                         return;
1068                 }
1069         }
1070
1071         if (crtc->ops->clock_enable)
1072                 crtc->ops->clock_enable(dp_to_crtc(dp), true);
1073
1074         phy_power_on(dp->phy);
1075         exynos_dp_init_dp(dp);
1076         enable_irq(dp->irq);
1077         exynos_dp_commit(&dp->encoder);
1078
1079         dp->dpms_mode = DRM_MODE_DPMS_ON;
1080 }
1081
1082 static void exynos_dp_bridge_disable(struct drm_bridge *bridge)
1083 {
1084         struct exynos_dp_device *dp = bridge->driver_private;
1085         struct exynos_drm_crtc *crtc = dp_to_crtc(dp);
1086
1087         if (dp->dpms_mode != DRM_MODE_DPMS_ON)
1088                 return;
1089
1090         if (dp->panel) {
1091                 if (drm_panel_disable(dp->panel)) {
1092                         DRM_ERROR("failed to disable the panel\n");
1093                         return;
1094                 }
1095         }
1096
1097         disable_irq(dp->irq);
1098         flush_work(&dp->hotplug_work);
1099         phy_power_off(dp->phy);
1100
1101         if (crtc->ops->clock_enable)
1102                 crtc->ops->clock_enable(dp_to_crtc(dp), false);
1103
1104         if (dp->panel) {
1105                 if (drm_panel_unprepare(dp->panel))
1106                         DRM_ERROR("failed to turnoff the panel\n");
1107         }
1108
1109         pm_runtime_put_sync(dp->dev);
1110
1111         dp->dpms_mode = DRM_MODE_DPMS_OFF;
1112 }
1113
1114 static void exynos_dp_bridge_nop(struct drm_bridge *bridge)
1115 {
1116         /* do nothing */
1117 }
1118
1119 static const struct drm_bridge_funcs exynos_dp_bridge_funcs = {
1120         .enable = exynos_dp_bridge_enable,
1121         .disable = exynos_dp_bridge_disable,
1122         .pre_enable = exynos_dp_bridge_nop,
1123         .post_disable = exynos_dp_bridge_nop,
1124         .attach = exynos_dp_bridge_attach,
1125 };
1126
1127 static int exynos_dp_create_connector(struct drm_encoder *encoder)
1128 {
1129         struct exynos_dp_device *dp = encoder_to_dp(encoder);
1130         struct drm_device *drm_dev = dp->drm_dev;
1131         struct drm_bridge *bridge;
1132         int ret;
1133
1134         bridge = devm_kzalloc(drm_dev->dev, sizeof(*bridge), GFP_KERNEL);
1135         if (!bridge) {
1136                 DRM_ERROR("failed to allocate for drm bridge\n");
1137                 return -ENOMEM;
1138         }
1139
1140         dp->bridge = bridge;
1141
1142         encoder->bridge = bridge;
1143         bridge->driver_private = dp;
1144         bridge->encoder = encoder;
1145         bridge->funcs = &exynos_dp_bridge_funcs;
1146
1147         ret = drm_bridge_attach(drm_dev, bridge);
1148         if (ret) {
1149                 DRM_ERROR("failed to attach drm bridge\n");
1150                 return -EINVAL;
1151         }
1152
1153         return 0;
1154 }
1155
1156 static void exynos_dp_mode_set(struct drm_encoder *encoder,
1157                                struct drm_display_mode *mode,
1158                                struct drm_display_mode *adjusted_mode)
1159 {
1160 }
1161
1162 static void exynos_dp_enable(struct drm_encoder *encoder)
1163 {
1164 }
1165
1166 static void exynos_dp_disable(struct drm_encoder *encoder)
1167 {
1168 }
1169
1170 static const struct drm_encoder_helper_funcs exynos_dp_encoder_helper_funcs = {
1171         .mode_set = exynos_dp_mode_set,
1172         .enable = exynos_dp_enable,
1173         .disable = exynos_dp_disable,
1174 };
1175
1176 static const struct drm_encoder_funcs exynos_dp_encoder_funcs = {
1177         .destroy = drm_encoder_cleanup,
1178 };
1179
1180 static struct video_info *exynos_dp_dt_parse_pdata(struct device *dev)
1181 {
1182         struct device_node *dp_node = dev->of_node;
1183         struct video_info *dp_video_config;
1184
1185         dp_video_config = devm_kzalloc(dev,
1186                                 sizeof(*dp_video_config), GFP_KERNEL);
1187         if (!dp_video_config)
1188                 return ERR_PTR(-ENOMEM);
1189
1190         dp_video_config->h_sync_polarity =
1191                 of_property_read_bool(dp_node, "hsync-active-high");
1192
1193         dp_video_config->v_sync_polarity =
1194                 of_property_read_bool(dp_node, "vsync-active-high");
1195
1196         dp_video_config->interlaced =
1197                 of_property_read_bool(dp_node, "interlaced");
1198
1199         if (of_property_read_u32(dp_node, "samsung,color-space",
1200                                 &dp_video_config->color_space)) {
1201                 dev_err(dev, "failed to get color-space\n");
1202                 return ERR_PTR(-EINVAL);
1203         }
1204
1205         if (of_property_read_u32(dp_node, "samsung,dynamic-range",
1206                                 &dp_video_config->dynamic_range)) {
1207                 dev_err(dev, "failed to get dynamic-range\n");
1208                 return ERR_PTR(-EINVAL);
1209         }
1210
1211         if (of_property_read_u32(dp_node, "samsung,ycbcr-coeff",
1212                                 &dp_video_config->ycbcr_coeff)) {
1213                 dev_err(dev, "failed to get ycbcr-coeff\n");
1214                 return ERR_PTR(-EINVAL);
1215         }
1216
1217         if (of_property_read_u32(dp_node, "samsung,color-depth",
1218                                 &dp_video_config->color_depth)) {
1219                 dev_err(dev, "failed to get color-depth\n");
1220                 return ERR_PTR(-EINVAL);
1221         }
1222
1223         if (of_property_read_u32(dp_node, "samsung,link-rate",
1224                                 &dp_video_config->link_rate)) {
1225                 dev_err(dev, "failed to get link-rate\n");
1226                 return ERR_PTR(-EINVAL);
1227         }
1228
1229         if (of_property_read_u32(dp_node, "samsung,lane-count",
1230                                 &dp_video_config->lane_count)) {
1231                 dev_err(dev, "failed to get lane-count\n");
1232                 return ERR_PTR(-EINVAL);
1233         }
1234
1235         return dp_video_config;
1236 }
1237
1238 static int exynos_dp_dt_parse_panel(struct exynos_dp_device *dp)
1239 {
1240         int ret;
1241
1242         ret = of_get_videomode(dp->dev->of_node, &dp->vm, OF_USE_NATIVE_MODE);
1243         if (ret) {
1244                 DRM_ERROR("failed: of_get_videomode() : %d\n", ret);
1245                 return ret;
1246         }
1247         return 0;
1248 }
1249
1250 static int exynos_dp_bind(struct device *dev, struct device *master, void *data)
1251 {
1252         struct exynos_dp_device *dp = dev_get_drvdata(dev);
1253         struct platform_device *pdev = to_platform_device(dev);
1254         struct drm_device *drm_dev = data;
1255         struct drm_encoder *encoder = &dp->encoder;
1256         struct resource *res;
1257         unsigned int irq_flags;
1258         int pipe, ret = 0;
1259
1260         dp->dev = &pdev->dev;
1261         dp->dpms_mode = DRM_MODE_DPMS_OFF;
1262
1263         dp->video_info = exynos_dp_dt_parse_pdata(&pdev->dev);
1264         if (IS_ERR(dp->video_info))
1265                 return PTR_ERR(dp->video_info);
1266
1267         dp->phy = devm_phy_get(dp->dev, "dp");
1268         if (IS_ERR(dp->phy)) {
1269                 dev_err(dp->dev, "no DP phy configured\n");
1270                 ret = PTR_ERR(dp->phy);
1271                 if (ret) {
1272                         /*
1273                          * phy itself is not enabled, so we can move forward
1274                          * assigning NULL to phy pointer.
1275                          */
1276                         if (ret == -ENOSYS || ret == -ENODEV)
1277                                 dp->phy = NULL;
1278                         else
1279                                 return ret;
1280                 }
1281         }
1282
1283         if (!dp->panel && !dp->ptn_bridge) {
1284                 ret = exynos_dp_dt_parse_panel(dp);
1285                 if (ret)
1286                         return ret;
1287         }
1288
1289         dp->clock = devm_clk_get(&pdev->dev, "dp");
1290         if (IS_ERR(dp->clock)) {
1291                 dev_err(&pdev->dev, "failed to get clock\n");
1292                 return PTR_ERR(dp->clock);
1293         }
1294
1295         clk_prepare_enable(dp->clock);
1296
1297         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1298
1299         dp->reg_base = devm_ioremap_resource(&pdev->dev, res);
1300         if (IS_ERR(dp->reg_base))
1301                 return PTR_ERR(dp->reg_base);
1302
1303         dp->hpd_gpio = of_get_named_gpio(dev->of_node, "samsung,hpd-gpio", 0);
1304
1305         if (gpio_is_valid(dp->hpd_gpio)) {
1306                 /*
1307                  * Set up the hotplug GPIO from the device tree as an interrupt.
1308                  * Simply specifying a different interrupt in the device tree
1309                  * doesn't work since we handle hotplug rather differently when
1310                  * using a GPIO.  We also need the actual GPIO specifier so
1311                  * that we can get the current state of the GPIO.
1312                  */
1313                 ret = devm_gpio_request_one(&pdev->dev, dp->hpd_gpio, GPIOF_IN,
1314                                             "hpd_gpio");
1315                 if (ret) {
1316                         dev_err(&pdev->dev, "failed to get hpd gpio\n");
1317                         return ret;
1318                 }
1319                 dp->irq = gpio_to_irq(dp->hpd_gpio);
1320                 irq_flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
1321         } else {
1322                 dp->hpd_gpio = -ENODEV;
1323                 dp->irq = platform_get_irq(pdev, 0);
1324                 irq_flags = 0;
1325         }
1326
1327         if (dp->irq == -ENXIO) {
1328                 dev_err(&pdev->dev, "failed to get irq\n");
1329                 return -ENODEV;
1330         }
1331
1332         INIT_WORK(&dp->hotplug_work, exynos_dp_hotplug);
1333
1334         ret = devm_request_irq(&pdev->dev, dp->irq, exynos_dp_irq_handler,
1335                         irq_flags, "exynos-dp", dp);
1336         if (ret) {
1337                 dev_err(&pdev->dev, "failed to request irq\n");
1338                 return ret;
1339         }
1340         disable_irq(dp->irq);
1341
1342         dp->drm_dev = drm_dev;
1343
1344         pipe = exynos_drm_crtc_get_pipe_from_type(drm_dev,
1345                                                   EXYNOS_DISPLAY_TYPE_LCD);
1346         if (pipe < 0)
1347                 return pipe;
1348
1349         encoder->possible_crtcs = 1 << pipe;
1350
1351         DRM_DEBUG_KMS("possible_crtcs = 0x%x\n", encoder->possible_crtcs);
1352
1353         drm_encoder_init(drm_dev, encoder, &exynos_dp_encoder_funcs,
1354                          DRM_MODE_ENCODER_TMDS, NULL);
1355
1356         drm_encoder_helper_add(encoder, &exynos_dp_encoder_helper_funcs);
1357
1358         ret = exynos_dp_create_connector(encoder);
1359         if (ret) {
1360                 DRM_ERROR("failed to create connector ret = %d\n", ret);
1361                 drm_encoder_cleanup(encoder);
1362                 return ret;
1363         }
1364
1365         return 0;
1366 }
1367
1368 static void exynos_dp_unbind(struct device *dev, struct device *master,
1369                                 void *data)
1370 {
1371         struct exynos_dp_device *dp = dev_get_drvdata(dev);
1372
1373         exynos_dp_disable(&dp->encoder);
1374 }
1375
1376 static const struct component_ops exynos_dp_ops = {
1377         .bind   = exynos_dp_bind,
1378         .unbind = exynos_dp_unbind,
1379 };
1380
1381 static int exynos_dp_probe(struct platform_device *pdev)
1382 {
1383         struct device *dev = &pdev->dev;
1384         struct device_node *np = NULL, *endpoint = NULL;
1385         struct exynos_dp_device *dp;
1386         int ret;
1387
1388         dp = devm_kzalloc(&pdev->dev, sizeof(struct exynos_dp_device),
1389                                 GFP_KERNEL);
1390         if (!dp)
1391                 return -ENOMEM;
1392
1393         platform_set_drvdata(pdev, dp);
1394
1395         /* This is for the backward compatibility. */
1396         np = of_parse_phandle(dev->of_node, "panel", 0);
1397         if (np) {
1398                 dp->panel = of_drm_find_panel(np);
1399                 of_node_put(np);
1400                 if (!dp->panel)
1401                         return -EPROBE_DEFER;
1402                 goto out;
1403         }
1404
1405         endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
1406         if (endpoint) {
1407                 np = of_graph_get_remote_port_parent(endpoint);
1408                 if (np) {
1409                         /* The remote port can be either a panel or a bridge */
1410                         dp->panel = of_drm_find_panel(np);
1411                         if (!dp->panel) {
1412                                 dp->ptn_bridge = of_drm_find_bridge(np);
1413                                 if (!dp->ptn_bridge) {
1414                                         of_node_put(np);
1415                                         return -EPROBE_DEFER;
1416                                 }
1417                         }
1418                         of_node_put(np);
1419                 } else {
1420                         DRM_ERROR("no remote endpoint device node found.\n");
1421                         return -EINVAL;
1422                 }
1423         } else {
1424                 DRM_ERROR("no port endpoint subnode found.\n");
1425                 return -EINVAL;
1426         }
1427
1428 out:
1429         pm_runtime_enable(dev);
1430
1431         ret = component_add(&pdev->dev, &exynos_dp_ops);
1432         if (ret)
1433                 goto err_disable_pm_runtime;
1434
1435         return ret;
1436
1437 err_disable_pm_runtime:
1438         pm_runtime_disable(dev);
1439
1440         return ret;
1441 }
1442
1443 static int exynos_dp_remove(struct platform_device *pdev)
1444 {
1445         pm_runtime_disable(&pdev->dev);
1446         component_del(&pdev->dev, &exynos_dp_ops);
1447
1448         return 0;
1449 }
1450
1451 #ifdef CONFIG_PM
1452 static int exynos_dp_suspend(struct device *dev)
1453 {
1454         struct exynos_dp_device *dp = dev_get_drvdata(dev);
1455
1456         clk_disable_unprepare(dp->clock);
1457
1458         return 0;
1459 }
1460
1461 static int exynos_dp_resume(struct device *dev)
1462 {
1463         struct exynos_dp_device *dp = dev_get_drvdata(dev);
1464         int ret;
1465
1466         ret = clk_prepare_enable(dp->clock);
1467         if (ret < 0) {
1468                 DRM_ERROR("Failed to prepare_enable the clock clk [%d]\n", ret);
1469                 return ret;
1470         }
1471
1472         return 0;
1473 }
1474 #endif
1475
1476 static const struct dev_pm_ops exynos_dp_pm_ops = {
1477         SET_RUNTIME_PM_OPS(exynos_dp_suspend, exynos_dp_resume, NULL)
1478 };
1479
1480 static const struct of_device_id exynos_dp_match[] = {
1481         { .compatible = "samsung,exynos5-dp" },
1482         {},
1483 };
1484 MODULE_DEVICE_TABLE(of, exynos_dp_match);
1485
1486 struct platform_driver dp_driver = {
1487         .probe          = exynos_dp_probe,
1488         .remove         = exynos_dp_remove,
1489         .driver         = {
1490                 .name   = "exynos-dp",
1491                 .owner  = THIS_MODULE,
1492                 .pm     = &exynos_dp_pm_ops,
1493                 .of_match_table = exynos_dp_match,
1494         },
1495 };
1496
1497 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
1498 MODULE_DESCRIPTION("Samsung SoC DP Driver");
1499 MODULE_LICENSE("GPL v2");