drivers/video/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/slab.h>
  16 #include <linux/err.h>
  17 #include <linux/clk.h>
  18 #include <linux/io.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/delay.h>
  21 #include <linux/of.h>
  22 #include <linux/phy/phy.h>
  23
  24 #include "exynos_dp_core.h"
  25
  26 static int exynos_dp_init_dp(struct exynos_dp_device *dp)
  27 {
  28         exynos_dp_reset(dp);
  29
  30         exynos_dp_swreset(dp);
  31
  32         exynos_dp_init_analog_param(dp);
  33         exynos_dp_init_interrupt(dp);
  34
  35         /* SW defined function Normal operation */
  36         exynos_dp_enable_sw_function(dp);
  37
  38         exynos_dp_config_interrupt(dp);
  39         exynos_dp_init_analog_func(dp);
  40
  41         exynos_dp_init_hpd(dp);
  42         exynos_dp_init_aux(dp);
  43
  44         return 0;
  45 }
  46
  47 static int exynos_dp_detect_hpd(struct exynos_dp_device *dp)
  48 {
  49         int timeout_loop = 0;
  50
  51         while (exynos_dp_get_plug_in_status(dp) != 0) {
  52                 timeout_loop++;
  53                 if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
  54                         dev_err(dp->dev, "failed to get hpd plug status\n");
  55                         return -ETIMEDOUT;
  56                 }
  57                 usleep_range(10, 11);
  58         }
  59
  60         return 0;
  61 }
  62
  63 static unsigned char exynos_dp_calc_edid_check_sum(unsigned char *edid_data)
  64 {
  65         int i;
  66         unsigned char sum = 0;
  67
  68         for (i = 0; i < EDID_BLOCK_LENGTH; i++)
  69                 sum = sum + edid_data[i];
  70
  71         return sum;
  72 }
  73
  74 static int exynos_dp_read_edid(struct exynos_dp_device *dp)
  75 {
  76         unsigned char edid[EDID_BLOCK_LENGTH * 2];
  77         unsigned int extend_block = 0;
  78         unsigned char sum;
  79         unsigned char test_vector;
  80         int retval;
  81
  82         /*
  83          * EDID device address is 0x50.
  84          * However, if necessary, you must have set upper address
  85          * into E-EDID in I2C device, 0x30.
  86          */
  87
  88         /* Read Extension Flag, Number of 128-byte EDID extension blocks */
  89         retval = exynos_dp_read_byte_from_i2c(dp, I2C_EDID_DEVICE_ADDR,
  90                                 EDID_EXTENSION_FLAG,
  91                                 &extend_block);
  92         if (retval)
  93                 return retval;
  94
  95         if (extend_block > 0) {
  96                 dev_dbg(dp->dev, "EDID data includes a single extension!\n");
  97
  98                 /* Read EDID data */
  99                 retval = exynos_dp_read_bytes_from_i2c(dp, I2C_EDID_DEVICE_ADDR,
 100                                                 EDID_HEADER_PATTERN,
 101                                                 EDID_BLOCK_LENGTH,
 102                                                 &edid[EDID_HEADER_PATTERN]);
 103                 if (retval != 0) {
 104                         dev_err(dp->dev, "EDID Read failed!\n");
 105                         return -EIO;
 106                 }
 107                 sum = exynos_dp_calc_edid_check_sum(edid);
 108                 if (sum != 0) {
 109                         dev_err(dp->dev, "EDID bad checksum!\n");
 110                         return -EIO;
 111                 }
 112
 113                 /* Read additional EDID data */
 114                 retval = exynos_dp_read_bytes_from_i2c(dp,
 115                                 I2C_EDID_DEVICE_ADDR,
 116                                 EDID_BLOCK_LENGTH,
 117                                 EDID_BLOCK_LENGTH,
 118                                 &edid[EDID_BLOCK_LENGTH]);
 119                 if (retval != 0) {
 120                         dev_err(dp->dev, "EDID Read failed!\n");
 121                         return -EIO;
 122                 }
 123                 sum = exynos_dp_calc_edid_check_sum(&edid[EDID_BLOCK_LENGTH]);
 124                 if (sum != 0) {
 125                         dev_err(dp->dev, "EDID bad checksum!\n");
 126                         return -EIO;
 127                 }
 128
 129                 exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_TEST_REQUEST,
 130                                         &test_vector);
 131                 if (test_vector & DPCD_TEST_EDID_READ) {
 132                         exynos_dp_write_byte_to_dpcd(dp,
 133                                 DPCD_ADDR_TEST_EDID_CHECKSUM,
 134                                 edid[EDID_BLOCK_LENGTH + EDID_CHECKSUM]);
 135                         exynos_dp_write_byte_to_dpcd(dp,
 136                                 DPCD_ADDR_TEST_RESPONSE,
 137                                 DPCD_TEST_EDID_CHECKSUM_WRITE);
 138                 }
 139         } else {
 140                 dev_info(dp->dev, "EDID data does not include any extensions.\n");
 141
 142                 /* Read EDID data */
 143                 retval = exynos_dp_read_bytes_from_i2c(dp,
 144                                 I2C_EDID_DEVICE_ADDR,
 145                                 EDID_HEADER_PATTERN,
 146                                 EDID_BLOCK_LENGTH,
 147                                 &edid[EDID_HEADER_PATTERN]);
 148                 if (retval != 0) {
 149                         dev_err(dp->dev, "EDID Read failed!\n");
 150                         return -EIO;
 151                 }
 152                 sum = exynos_dp_calc_edid_check_sum(edid);
 153                 if (sum != 0) {
 154                         dev_err(dp->dev, "EDID bad checksum!\n");
 155                         return -EIO;
 156                 }
 157
 158                 exynos_dp_read_byte_from_dpcd(dp,
 159                         DPCD_ADDR_TEST_REQUEST,
 160                         &test_vector);
 161                 if (test_vector & DPCD_TEST_EDID_READ) {
 162                         exynos_dp_write_byte_to_dpcd(dp,
 163                                 DPCD_ADDR_TEST_EDID_CHECKSUM,
 164                                 edid[EDID_CHECKSUM]);
 165                         exynos_dp_write_byte_to_dpcd(dp,
 166                                 DPCD_ADDR_TEST_RESPONSE,
 167                                 DPCD_TEST_EDID_CHECKSUM_WRITE);
 168                 }
 169         }
 170
 171         dev_err(dp->dev, "EDID Read success!\n");
 172         return 0;
 173 }
 174
 175 static int exynos_dp_handle_edid(struct exynos_dp_device *dp)
 176 {
 177         u8 buf[12];
 178         int i;
 179         int retval;
 180
 181         /* Read DPCD DPCD_ADDR_DPCD_REV~RECEIVE_PORT1_CAP_1 */
 182         retval = exynos_dp_read_bytes_from_dpcd(dp, DPCD_ADDR_DPCD_REV,
 183                                 12, buf);
 184         if (retval)
 185                 return retval;
 186
 187         /* Read EDID */
 188         for (i = 0; i < 3; i++) {
 189                 retval = exynos_dp_read_edid(dp);
 190                 if (!retval)
 191                         break;
 192         }
 193
 194         return retval;
 195 }
 196
 197 static void exynos_dp_enable_rx_to_enhanced_mode(struct exynos_dp_device *dp,
 198                                                 bool enable)
 199 {
 200         u8 data;
 201
 202         exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_LANE_COUNT_SET, &data);
 203
 204         if (enable)
 205                 exynos_dp_write_byte_to_dpcd(dp, DPCD_ADDR_LANE_COUNT_SET,
 206                         DPCD_ENHANCED_FRAME_EN |
 207                         DPCD_LANE_COUNT_SET(data));
 208         else
 209                 exynos_dp_write_byte_to_dpcd(dp, DPCD_ADDR_LANE_COUNT_SET,
 210                         DPCD_LANE_COUNT_SET(data));
 211 }
 212
 213 static int exynos_dp_is_enhanced_mode_available(struct exynos_dp_device *dp)
 214 {
 215         u8 data;
 216         int retval;
 217
 218         exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_MAX_LANE_COUNT, &data);
 219         retval = DPCD_ENHANCED_FRAME_CAP(data);
 220
 221         return retval;
 222 }
 223
 224 static void exynos_dp_set_enhanced_mode(struct exynos_dp_device *dp)
 225 {
 226         u8 data;
 227
 228         data = exynos_dp_is_enhanced_mode_available(dp);
 229         exynos_dp_enable_rx_to_enhanced_mode(dp, data);
 230         exynos_dp_enable_enhanced_mode(dp, data);
 231 }
 232
 233 static void exynos_dp_training_pattern_dis(struct exynos_dp_device *dp)
 234 {
 235         exynos_dp_set_training_pattern(dp, DP_NONE);
 236
 237         exynos_dp_write_byte_to_dpcd(dp,
 238                 DPCD_ADDR_TRAINING_PATTERN_SET,
 239                 DPCD_TRAINING_PATTERN_DISABLED);
 240 }
 241
 242 static void exynos_dp_set_lane_lane_pre_emphasis(struct exynos_dp_device *dp,
 243                                         int pre_emphasis, int lane)
 244 {
 245         switch (lane) {
 246         case 0:
 247                 exynos_dp_set_lane0_pre_emphasis(dp, pre_emphasis);
 248                 break;
 249         case 1:
 250                 exynos_dp_set_lane1_pre_emphasis(dp, pre_emphasis);
 251                 break;
 252
 253         case 2:
 254                 exynos_dp_set_lane2_pre_emphasis(dp, pre_emphasis);
 255                 break;
 256
 257         case 3:
 258                 exynos_dp_set_lane3_pre_emphasis(dp, pre_emphasis);
 259                 break;
 260         }
 261 }
 262
 263 static int exynos_dp_link_start(struct exynos_dp_device *dp)
 264 {
 265         u8 buf[4];
 266         int lane, lane_count, pll_tries, retval;
 267
 268         lane_count = dp->link_train.lane_count;
 269
 270         dp->link_train.lt_state = CLOCK_RECOVERY;
 271         dp->link_train.eq_loop = 0;
 272
 273         for (lane = 0; lane < lane_count; lane++)
 274                 dp->link_train.cr_loop[lane] = 0;
 275
 276         /* Set link rate and count as you want to establish*/
 277         exynos_dp_set_link_bandwidth(dp, dp->link_train.link_rate);
 278         exynos_dp_set_lane_count(dp, dp->link_train.lane_count);
 279
 280         /* Setup RX configuration */
 281         buf[0] = dp->link_train.link_rate;
 282         buf[1] = dp->link_train.lane_count;
 283         retval = exynos_dp_write_bytes_to_dpcd(dp, DPCD_ADDR_LINK_BW_SET,
 284                                 2, buf);
 285         if (retval)
 286                 return retval;
 287
 288         /* Set TX pre-emphasis to minimum */
 289         for (lane = 0; lane < lane_count; lane++)
 290                 exynos_dp_set_lane_lane_pre_emphasis(dp,
 291                         PRE_EMPHASIS_LEVEL_0, lane);
 292
 293         /* Wait for PLL lock */
 294         pll_tries = 0;
 295         while (exynos_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
 296                 if (pll_tries == DP_TIMEOUT_LOOP_COUNT) {
 297                         dev_err(dp->dev, "Wait for PLL lock timed out\n");
 298                         return -ETIMEDOUT;
 299                 }
 300
 301                 pll_tries++;
 302                 usleep_range(90, 120);
 303         }
 304
 305         /* Set training pattern 1 */
 306         exynos_dp_set_training_pattern(dp, TRAINING_PTN1);
 307
 308         /* Set RX training pattern */
 309         retval = exynos_dp_write_byte_to_dpcd(dp,
 310                         DPCD_ADDR_TRAINING_PATTERN_SET,
 311                         DPCD_SCRAMBLING_DISABLED | DPCD_TRAINING_PATTERN_1);
 312         if (retval)
 313                 return retval;
 314
 315         for (lane = 0; lane < lane_count; lane++)
 316                 buf[lane] = DPCD_PRE_EMPHASIS_PATTERN2_LEVEL0 |
 317                             DPCD_VOLTAGE_SWING_PATTERN1_LEVEL0;
 318
 319         retval = exynos_dp_write_bytes_to_dpcd(dp, DPCD_ADDR_TRAINING_LANE0_SET,
 320                         lane_count, buf);
 321
 322         return retval;
 323 }
 324
 325 static unsigned char exynos_dp_get_lane_status(u8 link_status[2], int lane)
 326 {
 327         int shift = (lane & 1) * 4;
 328         u8 link_value = link_status[lane>>1];
 329
 330         return (link_value >> shift) & 0xf;
 331 }
 332
 333 static int exynos_dp_clock_recovery_ok(u8 link_status[2], int lane_count)
 334 {
 335         int lane;
 336         u8 lane_status;
 337
 338         for (lane = 0; lane < lane_count; lane++) {
 339                 lane_status = exynos_dp_get_lane_status(link_status, lane);
 340                 if ((lane_status & DPCD_LANE_CR_DONE) == 0)
 341                         return -EINVAL;
 342         }
 343         return 0;
 344 }
 345
 346 static int exynos_dp_channel_eq_ok(u8 link_status[2], u8 link_align,
 347                                 int lane_count)
 348 {
 349         int lane;
 350         u8 lane_status;
 351
 352         if ((link_align & DPCD_INTERLANE_ALIGN_DONE) == 0)
 353                 return -EINVAL;
 354
 355         for (lane = 0; lane < lane_count; lane++) {
 356                 lane_status = exynos_dp_get_lane_status(link_status, lane);
 357                 lane_status &= DPCD_CHANNEL_EQ_BITS;
 358                 if (lane_status != DPCD_CHANNEL_EQ_BITS)
 359                         return -EINVAL;
 360         }
 361
 362         return 0;
 363 }
 364
 365 static unsigned char exynos_dp_get_adjust_request_voltage(u8 adjust_request[2],
 366                                                         int lane)
 367 {
 368         int shift = (lane & 1) * 4;
 369         u8 link_value = adjust_request[lane>>1];
 370
 371         return (link_value >> shift) & 0x3;
 372 }
 373
 374 static unsigned char exynos_dp_get_adjust_request_pre_emphasis(
 375                                         u8 adjust_request[2],
 376                                         int lane)
 377 {
 378         int shift = (lane & 1) * 4;
 379         u8 link_value = adjust_request[lane>>1];
 380
 381         return ((link_value >> shift) & 0xc) >> 2;
 382 }
 383
 384 static void exynos_dp_set_lane_link_training(struct exynos_dp_device *dp,
 385                                         u8 training_lane_set, int lane)
 386 {
 387         switch (lane) {
 388         case 0:
 389                 exynos_dp_set_lane0_link_training(dp, training_lane_set);
 390                 break;
 391         case 1:
 392                 exynos_dp_set_lane1_link_training(dp, training_lane_set);
 393                 break;
 394
 395         case 2:
 396                 exynos_dp_set_lane2_link_training(dp, training_lane_set);
 397                 break;
 398
 399         case 3:
 400                 exynos_dp_set_lane3_link_training(dp, training_lane_set);
 401                 break;
 402         }
 403 }
 404
 405 static unsigned int exynos_dp_get_lane_link_training(
 406                                 struct exynos_dp_device *dp,
 407                                 int lane)
 408 {
 409         u32 reg;
 410
 411         switch (lane) {
 412         case 0:
 413                 reg = exynos_dp_get_lane0_link_training(dp);
 414                 break;
 415         case 1:
 416                 reg = exynos_dp_get_lane1_link_training(dp);
 417                 break;
 418         case 2:
 419                 reg = exynos_dp_get_lane2_link_training(dp);
 420                 break;
 421         case 3:
 422                 reg = exynos_dp_get_lane3_link_training(dp);
 423                 break;
 424         default:
 425                 WARN_ON(1);
 426                 return 0;
 427         }
 428
 429         return reg;
 430 }
 431
 432 static void exynos_dp_reduce_link_rate(struct exynos_dp_device *dp)
 433 {
 434         exynos_dp_training_pattern_dis(dp);
 435         exynos_dp_set_enhanced_mode(dp);
 436
 437         dp->link_train.lt_state = FAILED;
 438 }
 439
 440 static void exynos_dp_get_adjust_training_lane(struct exynos_dp_device *dp,
 441                                         u8 adjust_request[2])
 442 {
 443         int lane, lane_count;
 444         u8 voltage_swing, pre_emphasis, training_lane;
 445
 446         lane_count = dp->link_train.lane_count;
 447         for (lane = 0; lane < lane_count; lane++) {
 448                 voltage_swing = exynos_dp_get_adjust_request_voltage(
 449                                                 adjust_request, lane);
 450                 pre_emphasis = exynos_dp_get_adjust_request_pre_emphasis(
 451                                                 adjust_request, lane);
 452                 training_lane = DPCD_VOLTAGE_SWING_SET(voltage_swing) |
 453                                 DPCD_PRE_EMPHASIS_SET(pre_emphasis);
 454
 455                 if (voltage_swing == VOLTAGE_LEVEL_3)
 456                         training_lane |= DPCD_MAX_SWING_REACHED;
 457                 if (pre_emphasis == PRE_EMPHASIS_LEVEL_3)
 458                         training_lane |= DPCD_MAX_PRE_EMPHASIS_REACHED;
 459
 460                 dp->link_train.training_lane[lane] = training_lane;
 461         }
 462 }
 463
 464 static int exynos_dp_process_clock_recovery(struct exynos_dp_device *dp)
 465 {
 466         int lane, lane_count, retval;
 467         u8 voltage_swing, pre_emphasis, training_lane;
 468         u8 link_status[2], adjust_request[2];
 469
 470         usleep_range(100, 101);
 471
 472         lane_count = dp->link_train.lane_count;
 473
 474         retval =  exynos_dp_read_bytes_from_dpcd(dp,
 475                         DPCD_ADDR_LANE0_1_STATUS, 2, link_status);
 476         if (retval)
 477                 return retval;
 478
 479         retval =  exynos_dp_read_bytes_from_dpcd(dp,
 480                         DPCD_ADDR_ADJUST_REQUEST_LANE0_1, 2, adjust_request);
 481         if (retval)
 482                 return retval;
 483
 484         if (exynos_dp_clock_recovery_ok(link_status, lane_count) == 0) {
 485                 /* set training pattern 2 for EQ */
 486                 exynos_dp_set_training_pattern(dp, TRAINING_PTN2);
 487
 488                 retval = exynos_dp_write_byte_to_dpcd(dp,
 489                                 DPCD_ADDR_TRAINING_PATTERN_SET,
 490                                 DPCD_SCRAMBLING_DISABLED |
 491                                 DPCD_TRAINING_PATTERN_2);
 492                 if (retval)
 493                         return retval;
 494
 495                 dev_info(dp->dev, "Link Training Clock Recovery success\n");
 496                 dp->link_train.lt_state = EQUALIZER_TRAINING;
 497         } else {
 498                 for (lane = 0; lane < lane_count; lane++) {
 499                         training_lane = exynos_dp_get_lane_link_training(
 500                                                         dp, lane);
 501                         voltage_swing = exynos_dp_get_adjust_request_voltage(
 502                                                         adjust_request, lane);
 503                         pre_emphasis = exynos_dp_get_adjust_request_pre_emphasis(
 504                                                         adjust_request, lane);
 505
 506                         if (DPCD_VOLTAGE_SWING_GET(training_lane) ==
 507                                         voltage_swing &&
 508                             DPCD_PRE_EMPHASIS_GET(training_lane) ==
 509                                         pre_emphasis)
 510                                 dp->link_train.cr_loop[lane]++;
 511
 512                         if (dp->link_train.cr_loop[lane] == MAX_CR_LOOP ||
 513                             voltage_swing == VOLTAGE_LEVEL_3 ||
 514                             pre_emphasis == PRE_EMPHASIS_LEVEL_3) {
 515                                 dev_err(dp->dev, "CR Max reached (%d,%d,%d)\n",
 516                                         dp->link_train.cr_loop[lane],
 517                                         voltage_swing, pre_emphasis);
 518                                 exynos_dp_reduce_link_rate(dp);
 519                                 return -EIO;
 520                         }
 521                 }
 522         }
 523
 524         exynos_dp_get_adjust_training_lane(dp, adjust_request);
 525
 526         for (lane = 0; lane < lane_count; lane++)
 527                 exynos_dp_set_lane_link_training(dp,
 528                         dp->link_train.training_lane[lane], lane);
 529
 530         retval = exynos_dp_write_bytes_to_dpcd(dp,
 531                         DPCD_ADDR_TRAINING_LANE0_SET, lane_count,
 532                         dp->link_train.training_lane);
 533         if (retval)
 534                 return retval;
 535
 536         return retval;
 537 }
 538
 539 static int exynos_dp_process_equalizer_training(struct exynos_dp_device *dp)
 540 {
 541         int lane, lane_count, retval;
 542         u32 reg;
 543         u8 link_align, link_status[2], adjust_request[2];
 544
 545         usleep_range(400, 401);
 546
 547         lane_count = dp->link_train.lane_count;
 548
 549         retval = exynos_dp_read_bytes_from_dpcd(dp,
 550                         DPCD_ADDR_LANE0_1_STATUS, 2, link_status);
 551         if (retval)
 552                 return retval;
 553
 554         if (exynos_dp_clock_recovery_ok(link_status, lane_count)) {
 555                 exynos_dp_reduce_link_rate(dp);
 556                 return -EIO;
 557         }
 558
 559         retval = exynos_dp_read_bytes_from_dpcd(dp,
 560                         DPCD_ADDR_ADJUST_REQUEST_LANE0_1, 2, adjust_request);
 561         if (retval)
 562                 return retval;
 563
 564         retval = exynos_dp_read_byte_from_dpcd(dp,
 565                         DPCD_ADDR_LANE_ALIGN_STATUS_UPDATED, &link_align);
 566         if (retval)
 567                 return retval;
 568
 569         exynos_dp_get_adjust_training_lane(dp, adjust_request);
 570
 571         if (!exynos_dp_channel_eq_ok(link_status, link_align, lane_count)) {
 572                 /* traing pattern Set to Normal */
 573                 exynos_dp_training_pattern_dis(dp);
 574
 575                 dev_info(dp->dev, "Link Training success!\n");
 576
 577                 exynos_dp_get_link_bandwidth(dp, &reg);
 578                 dp->link_train.link_rate = reg;
 579                 dev_dbg(dp->dev, "final bandwidth = %.2x\n",
 580                         dp->link_train.link_rate);
 581
 582                 exynos_dp_get_lane_count(dp, &reg);
 583                 dp->link_train.lane_count = reg;
 584                 dev_dbg(dp->dev, "final lane count = %.2x\n",
 585                         dp->link_train.lane_count);
 586
 587                 /* set enhanced mode if available */
 588                 exynos_dp_set_enhanced_mode(dp);
 589                 dp->link_train.lt_state = FINISHED;
 590
 591                 return 0;
 592         }
 593
 594         /* not all locked */
 595         dp->link_train.eq_loop++;
 596
 597         if (dp->link_train.eq_loop > MAX_EQ_LOOP) {
 598                 dev_err(dp->dev, "EQ Max loop\n");
 599                 exynos_dp_reduce_link_rate(dp);
 600                 return -EIO;
 601         }
 602
 603         for (lane = 0; lane < lane_count; lane++)
 604                 exynos_dp_set_lane_link_training(dp,
 605                         dp->link_train.training_lane[lane], lane);
 606
 607         retval = exynos_dp_write_bytes_to_dpcd(dp, DPCD_ADDR_TRAINING_LANE0_SET,
 608                         lane_count, dp->link_train.training_lane);
 609
 610         return retval;
 611 }
 612
 613 static void exynos_dp_get_max_rx_bandwidth(struct exynos_dp_device *dp,
 614                                         u8 *bandwidth)
 615 {
 616         u8 data;
 617
 618         /*
 619          * For DP rev.1.1, Maximum link rate of Main Link lanes
 620          * 0x06 = 1.62 Gbps, 0x0a = 2.7 Gbps
 621          */
 622         exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_MAX_LINK_RATE, &data);
 623         *bandwidth = data;
 624 }
 625
 626 static void exynos_dp_get_max_rx_lane_count(struct exynos_dp_device *dp,
 627                                         u8 *lane_count)
 628 {
 629         u8 data;
 630
 631         /*
 632          * For DP rev.1.1, Maximum number of Main Link lanes
 633          * 0x01 = 1 lane, 0x02 = 2 lanes, 0x04 = 4 lanes
 634          */
 635         exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_MAX_LANE_COUNT, &data);
 636         *lane_count = DPCD_MAX_LANE_COUNT(data);
 637 }
 638
 639 static void exynos_dp_init_training(struct exynos_dp_device *dp,
 640                         enum link_lane_count_type max_lane,
 641                         enum link_rate_type max_rate)
 642 {
 643         /*
 644          * MACRO_RST must be applied after the PLL_LOCK to avoid
 645          * the DP inter pair skew issue for at least 10 us
 646          */
 647         exynos_dp_reset_macro(dp);
 648
 649         /* Initialize by reading RX's DPCD */
 650         exynos_dp_get_max_rx_bandwidth(dp, &dp->link_train.link_rate);
 651         exynos_dp_get_max_rx_lane_count(dp, &dp->link_train.lane_count);
 652
 653         if ((dp->link_train.link_rate != LINK_RATE_1_62GBPS) &&
 654            (dp->link_train.link_rate != LINK_RATE_2_70GBPS)) {
 655                 dev_err(dp->dev, "Rx Max Link Rate is abnormal :%x !\n",
 656                         dp->link_train.link_rate);
 657                 dp->link_train.link_rate = LINK_RATE_1_62GBPS;
 658         }
 659
 660         if (dp->link_train.lane_count == 0) {
 661                 dev_err(dp->dev, "Rx Max Lane count is abnormal :%x !\n",
 662                         dp->link_train.lane_count);
 663                 dp->link_train.lane_count = (u8)LANE_COUNT1;
 664         }
 665
 666         /* Setup TX lane count & rate */
 667         if (dp->link_train.lane_count > max_lane)
 668                 dp->link_train.lane_count = max_lane;
 669         if (dp->link_train.link_rate > max_rate)
 670                 dp->link_train.link_rate = max_rate;
 671
 672         /* All DP analog module power up */
 673         exynos_dp_set_analog_power_down(dp, POWER_ALL, 0);
 674 }
 675
 676 static int exynos_dp_sw_link_training(struct exynos_dp_device *dp)
 677 {
 678         int retval = 0, training_finished = 0;
 679
 680         dp->link_train.lt_state = START;
 681
 682         /* Process here */
 683         while (!retval && !training_finished) {
 684                 switch (dp->link_train.lt_state) {
 685                 case START:
 686                         retval = exynos_dp_link_start(dp);
 687                         if (retval)
 688                                 dev_err(dp->dev, "LT link start failed!\n");
 689                         break;
 690                 case CLOCK_RECOVERY:
 691                         retval = exynos_dp_process_clock_recovery(dp);
 692                         if (retval)
 693                                 dev_err(dp->dev, "LT CR failed!\n");
 694                         break;
 695                 case EQUALIZER_TRAINING:
 696                         retval = exynos_dp_process_equalizer_training(dp);
 697                         if (retval)
 698                                 dev_err(dp->dev, "LT EQ failed!\n");
 699                         break;
 700                 case FINISHED:
 701                         training_finished = 1;
 702                         break;
 703                 case FAILED:
 704                         return -EREMOTEIO;
 705                 }
 706         }
 707         if (retval)
 708                 dev_err(dp->dev, "eDP link training failed (%d)\n", retval);
 709
 710         return retval;
 711 }
 712
 713 static int exynos_dp_set_link_train(struct exynos_dp_device *dp,
 714                                 u32 count,
 715                                 u32 bwtype)
 716 {
 717         int i;
 718         int retval;
 719
 720         for (i = 0; i < DP_TIMEOUT_LOOP_COUNT; i++) {
 721                 exynos_dp_init_training(dp, count, bwtype);
 722                 retval = exynos_dp_sw_link_training(dp);
 723                 if (retval == 0)
 724                         break;
 725
 726                 usleep_range(100, 110);
 727         }
 728
 729         return retval;
 730 }
 731
 732 static int exynos_dp_config_video(struct exynos_dp_device *dp)
 733 {
 734         int retval = 0;
 735         int timeout_loop = 0;
 736         int done_count = 0;
 737
 738         exynos_dp_config_video_slave_mode(dp);
 739
 740         exynos_dp_set_video_color_format(dp);
 741
 742         if (exynos_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
 743                 dev_err(dp->dev, "PLL is not locked yet.\n");
 744                 return -EINVAL;
 745         }
 746
 747         for (;;) {
 748                 timeout_loop++;
 749                 if (exynos_dp_is_slave_video_stream_clock_on(dp) == 0)
 750                         break;
 751                 if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
 752                         dev_err(dp->dev, "Timeout of video streamclk ok\n");
 753                         return -ETIMEDOUT;
 754                 }
 755
 756                 usleep_range(1, 2);
 757         }
 758
 759         /* Set to use the register calculated M/N video */
 760         exynos_dp_set_video_cr_mn(dp, CALCULATED_M, 0, 0);
 761
 762         /* For video bist, Video timing must be generated by register */
 763         exynos_dp_set_video_timing_mode(dp, VIDEO_TIMING_FROM_CAPTURE);
 764
 765         /* Disable video mute */
 766         exynos_dp_enable_video_mute(dp, 0);
 767
 768         /* Configure video slave mode */
 769         exynos_dp_enable_video_master(dp, 0);
 770
 771         /* Enable video */
 772         exynos_dp_start_video(dp);
 773
 774         timeout_loop = 0;
 775
 776         for (;;) {
 777                 timeout_loop++;
 778                 if (exynos_dp_is_video_stream_on(dp) == 0) {
 779                         done_count++;
 780                         if (done_count > 10)
 781                                 break;
 782                 } else if (done_count) {
 783                         done_count = 0;
 784                 }
 785                 if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
 786                         dev_err(dp->dev, "Timeout of video streamclk ok\n");
 787                         return -ETIMEDOUT;
 788                 }
 789
 790                 usleep_range(1000, 1001);
 791         }
 792
 793         if (retval != 0)
 794                 dev_err(dp->dev, "Video stream is not detected!\n");
 795
 796         return retval;
 797 }
 798
 799 static void exynos_dp_enable_scramble(struct exynos_dp_device *dp, bool enable)
 800 {
 801         u8 data;
 802
 803         if (enable) {
 804                 exynos_dp_enable_scrambling(dp);
 805
 806                 exynos_dp_read_byte_from_dpcd(dp,
 807                         DPCD_ADDR_TRAINING_PATTERN_SET,
 808                         &data);
 809                 exynos_dp_write_byte_to_dpcd(dp,
 810                         DPCD_ADDR_TRAINING_PATTERN_SET,
 811                         (u8)(data & ~DPCD_SCRAMBLING_DISABLED));
 812         } else {
 813                 exynos_dp_disable_scrambling(dp);
 814
 815                 exynos_dp_read_byte_from_dpcd(dp,
 816                         DPCD_ADDR_TRAINING_PATTERN_SET,
 817                         &data);
 818                 exynos_dp_write_byte_to_dpcd(dp,
 819                         DPCD_ADDR_TRAINING_PATTERN_SET,
 820                         (u8)(data | DPCD_SCRAMBLING_DISABLED));
 821         }
 822 }
 823
 824 static irqreturn_t exynos_dp_irq_handler(int irq, void *arg)
 825 {
 826         struct exynos_dp_device *dp = arg;
 827
 828         enum dp_irq_type irq_type;
 829
 830         irq_type = exynos_dp_get_irq_type(dp);
 831         switch (irq_type) {
 832         case DP_IRQ_TYPE_HP_CABLE_IN:
 833                 dev_dbg(dp->dev, "Received irq - cable in\n");
 834                 schedule_work(&dp->hotplug_work);
 835                 exynos_dp_clear_hotplug_interrupts(dp);
 836                 break;
 837         case DP_IRQ_TYPE_HP_CABLE_OUT:
 838                 dev_dbg(dp->dev, "Received irq - cable out\n");
 839                 exynos_dp_clear_hotplug_interrupts(dp);
 840                 break;
 841         case DP_IRQ_TYPE_HP_CHANGE:
 842                 /*
 843                  * We get these change notifications once in a while, but there
 844                  * is nothing we can do with them. Just ignore it for now and
 845                  * only handle cable changes.
 846                  */
 847                 dev_dbg(dp->dev, "Received irq - hotplug change; ignoring.\n");
 848                 exynos_dp_clear_hotplug_interrupts(dp);
 849                 break;
 850         default:
 851                 dev_err(dp->dev, "Received irq - unknown type!\n");
 852                 break;
 853         }
 854         return IRQ_HANDLED;
 855 }
 856
 857 static void exynos_dp_hotplug(struct work_struct *work)
 858 {
 859         struct exynos_dp_device *dp;
 860         int ret;
 861
 862         dp = container_of(work, struct exynos_dp_device, hotplug_work);
 863
 864         ret = exynos_dp_detect_hpd(dp);
 865         if (ret) {
 866                 /* Cable has been disconnected, we're done */
 867                 return;
 868         }
 869
 870         ret = exynos_dp_handle_edid(dp);
 871         if (ret) {
 872                 dev_err(dp->dev, "unable to handle edid\n");
 873                 return;
 874         }
 875
 876         ret = exynos_dp_set_link_train(dp, dp->video_info->lane_count,
 877                                         dp->video_info->link_rate);
 878         if (ret) {
 879                 dev_err(dp->dev, "unable to do link train\n");
 880                 return;
 881         }
 882
 883         exynos_dp_enable_scramble(dp, 1);
 884         exynos_dp_enable_rx_to_enhanced_mode(dp, 1);
 885         exynos_dp_enable_enhanced_mode(dp, 1);
 886
 887         exynos_dp_set_lane_count(dp, dp->video_info->lane_count);
 888         exynos_dp_set_link_bandwidth(dp, dp->video_info->link_rate);
 889
 890         exynos_dp_init_video(dp);
 891         ret = exynos_dp_config_video(dp);
 892         if (ret)
 893                 dev_err(dp->dev, "unable to config video\n");
 894 }
 895
 896 static struct video_info *exynos_dp_dt_parse_pdata(struct device *dev)
 897 {
 898         struct device_node *dp_node = dev->of_node;
 899         struct video_info *dp_video_config;
 900
 901         dp_video_config = devm_kzalloc(dev,
 902                                 sizeof(*dp_video_config), GFP_KERNEL);
 903         if (!dp_video_config) {
 904                 dev_err(dev, "memory allocation for video config failed\n");
 905                 return ERR_PTR(-ENOMEM);
 906         }
 907
 908         dp_video_config->h_sync_polarity =
 909                 of_property_read_bool(dp_node, "hsync-active-high");
 910
 911         dp_video_config->v_sync_polarity =
 912                 of_property_read_bool(dp_node, "vsync-active-high");
 913
 914         dp_video_config->interlaced =
 915                 of_property_read_bool(dp_node, "interlaced");
 916
 917         if (of_property_read_u32(dp_node, "samsung,color-space",
 918                                 &dp_video_config->color_space)) {
 919                 dev_err(dev, "failed to get color-space\n");
 920                 return ERR_PTR(-EINVAL);
 921         }
 922
 923         if (of_property_read_u32(dp_node, "samsung,dynamic-range",
 924                                 &dp_video_config->dynamic_range)) {
 925                 dev_err(dev, "failed to get dynamic-range\n");
 926                 return ERR_PTR(-EINVAL);
 927         }
 928
 929         if (of_property_read_u32(dp_node, "samsung,ycbcr-coeff",
 930                                 &dp_video_config->ycbcr_coeff)) {
 931                 dev_err(dev, "failed to get ycbcr-coeff\n");
 932                 return ERR_PTR(-EINVAL);
 933         }
 934
 935         if (of_property_read_u32(dp_node, "samsung,color-depth",
 936                                 &dp_video_config->color_depth)) {
 937                 dev_err(dev, "failed to get color-depth\n");
 938                 return ERR_PTR(-EINVAL);
 939         }
 940
 941         if (of_property_read_u32(dp_node, "samsung,link-rate",
 942                                 &dp_video_config->link_rate)) {
 943                 dev_err(dev, "failed to get link-rate\n");
 944                 return ERR_PTR(-EINVAL);
 945         }
 946
 947         if (of_property_read_u32(dp_node, "samsung,lane-count",
 948                                 &dp_video_config->lane_count)) {
 949                 dev_err(dev, "failed to get lane-count\n");
 950                 return ERR_PTR(-EINVAL);
 951         }
 952
 953         return dp_video_config;
 954 }
 955
 956 static int exynos_dp_dt_parse_phydata(struct exynos_dp_device *dp)
 957 {
 958         struct device_node *dp_phy_node = of_node_get(dp->dev->of_node);
 959         u32 phy_base;
 960         int ret = 0;
 961
 962         dp_phy_node = of_find_node_by_name(dp_phy_node, "dptx-phy");
 963         if (!dp_phy_node) {
 964                 dp->phy = devm_phy_get(dp->dev, "dp");
 965                 if (IS_ERR(dp->phy))
 966                         return PTR_ERR(dp->phy);
 967                 else
 968                         return 0;
 969         }
 970
 971         if (of_property_read_u32(dp_phy_node, "reg", &phy_base)) {
 972                 dev_err(dp->dev, "failed to get reg for dptx-phy\n");
 973                 ret = -EINVAL;
 974                 goto err;
 975         }
 976
 977         if (of_property_read_u32(dp_phy_node, "samsung,enable-mask",
 978                                 &dp->enable_mask)) {
 979                 dev_err(dp->dev, "failed to get enable-mask for dptx-phy\n");
 980                 ret = -EINVAL;
 981                 goto err;
 982         }
 983
 984         dp->phy_addr = ioremap(phy_base, SZ_4);
 985         if (!dp->phy_addr) {
 986                 dev_err(dp->dev, "failed to ioremap dp-phy\n");
 987                 ret = -ENOMEM;
 988                 goto err;
 989         }
 990
 991 err:
 992         of_node_put(dp_phy_node);
 993
 994         return ret;
 995 }
 996
 997 static void exynos_dp_phy_init(struct exynos_dp_device *dp)
 998 {
 999         if (dp->phy) {
1000                 phy_power_on(dp->phy);
1001         } else if (dp->phy_addr) {
1002                 u32 reg;
1003
1004                 reg = __raw_readl(dp->phy_addr);
1005                 reg |= dp->enable_mask;
1006                 __raw_writel(reg, dp->phy_addr);
1007         }
1008 }
1009
1010 static void exynos_dp_phy_exit(struct exynos_dp_device *dp)
1011 {
1012         if (dp->phy) {
1013                 phy_power_off(dp->phy);
1014         } else if (dp->phy_addr) {
1015                 u32 reg;
1016
1017                 reg = __raw_readl(dp->phy_addr);
1018                 reg &= ~(dp->enable_mask);
1019                 __raw_writel(reg, dp->phy_addr);
1020         }
1021 }
1022
1023 static int exynos_dp_probe(struct platform_device *pdev)
1024 {
1025         struct resource *res;
1026         struct exynos_dp_device *dp;
1027
1028         int ret = 0;
1029
1030         dp = devm_kzalloc(&pdev->dev, sizeof(struct exynos_dp_device),
1031                                 GFP_KERNEL);
1032         if (!dp) {
1033                 dev_err(&pdev->dev, "no memory for device data\n");
1034                 return -ENOMEM;
1035         }
1036
1037         dp->dev = &pdev->dev;
1038
1039         dp->video_info = exynos_dp_dt_parse_pdata(&pdev->dev);
1040         if (IS_ERR(dp->video_info))
1041                 return PTR_ERR(dp->video_info);
1042
1043         ret = exynos_dp_dt_parse_phydata(dp);
1044         if (ret)
1045                 return ret;
1046
1047         dp->clock = devm_clk_get(&pdev->dev, "dp");
1048         if (IS_ERR(dp->clock)) {
1049                 dev_err(&pdev->dev, "failed to get clock\n");
1050                 return PTR_ERR(dp->clock);
1051         }
1052
1053         clk_prepare_enable(dp->clock);
1054
1055         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1056
1057         dp->reg_base = devm_ioremap_resource(&pdev->dev, res);
1058         if (IS_ERR(dp->reg_base))
1059                 return PTR_ERR(dp->reg_base);
1060
1061         dp->irq = platform_get_irq(pdev, 0);
1062         if (dp->irq == -ENXIO) {
1063                 dev_err(&pdev->dev, "failed to get irq\n");
1064                 return -ENODEV;
1065         }
1066
1067         INIT_WORK(&dp->hotplug_work, exynos_dp_hotplug);
1068
1069         exynos_dp_phy_init(dp);
1070
1071         exynos_dp_init_dp(dp);
1072
1073         ret = devm_request_irq(&pdev->dev, dp->irq, exynos_dp_irq_handler, 0,
1074                                 "exynos-dp", dp);
1075         if (ret) {
1076                 dev_err(&pdev->dev, "failed to request irq\n");
1077                 return ret;
1078         }
1079
1080         platform_set_drvdata(pdev, dp);
1081
1082         return 0;
1083 }
1084
1085 static int exynos_dp_remove(struct platform_device *pdev)
1086 {
1087         struct exynos_dp_device *dp = platform_get_drvdata(pdev);
1088
1089         flush_work(&dp->hotplug_work);
1090
1091         exynos_dp_phy_exit(dp);
1092
1093         clk_disable_unprepare(dp->clock);
1094
1095
1096         return 0;
1097 }
1098
1099 #ifdef CONFIG_PM_SLEEP
1100 static int exynos_dp_suspend(struct device *dev)
1101 {
1102         struct exynos_dp_device *dp = dev_get_drvdata(dev);
1103
1104         disable_irq(dp->irq);
1105
1106         flush_work(&dp->hotplug_work);
1107
1108         exynos_dp_phy_exit(dp);
1109
1110         clk_disable_unprepare(dp->clock);
1111
1112         return 0;
1113 }
1114
1115 static int exynos_dp_resume(struct device *dev)
1116 {
1117         struct exynos_dp_device *dp = dev_get_drvdata(dev);
1118
1119         exynos_dp_phy_init(dp);
1120
1121         clk_prepare_enable(dp->clock);
1122
1123         exynos_dp_init_dp(dp);
1124
1125         enable_irq(dp->irq);
1126
1127         return 0;
1128 }
1129 #endif
1130
1131 static const struct dev_pm_ops exynos_dp_pm_ops = {
1132         SET_SYSTEM_SLEEP_PM_OPS(exynos_dp_suspend, exynos_dp_resume)
1133 };
1134
1135 static const struct of_device_id exynos_dp_match[] = {
1136         { .compatible = "samsung,exynos5-dp" },
1137         {},
1138 };
1139 MODULE_DEVICE_TABLE(of, exynos_dp_match);
1140
1141 static struct platform_driver exynos_dp_driver = {
1142         .probe          = exynos_dp_probe,
1143         .remove         = exynos_dp_remove,
1144         .driver         = {
1145                 .name   = "exynos-dp",
1146                 .owner  = THIS_MODULE,
1147                 .pm     = &exynos_dp_pm_ops,
1148                 .of_match_table = exynos_dp_match,
1149         },
1150 };
1151
1152 module_platform_driver(exynos_dp_driver);
1153
1154 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
1155 MODULE_DESCRIPTION("Samsung SoC DP Driver");
1156 MODULE_LICENSE("GPL");