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
  22 #include <video/exynos_dp.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         exynos_dp_init_hpd(dp);
  52
  53         usleep_range(200, 210);
  54
  55         while (exynos_dp_get_plug_in_status(dp) != 0) {
  56                 timeout_loop++;
  57                 if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
  58                         dev_err(dp->dev, "failed to get hpd plug status\n");
  59                         return -ETIMEDOUT;
  60                 }
  61                 usleep_range(10, 11);
  62         }
  63
  64         return 0;
  65 }
  66
  67 static unsigned char exynos_dp_calc_edid_check_sum(unsigned char *edid_data)
  68 {
  69         int i;
  70         unsigned char sum = 0;
  71
  72         for (i = 0; i < EDID_BLOCK_LENGTH; i++)
  73                 sum = sum + edid_data[i];
  74
  75         return sum;
  76 }
  77
  78 static int exynos_dp_read_edid(struct exynos_dp_device *dp)
  79 {
  80         unsigned char edid[EDID_BLOCK_LENGTH * 2];
  81         unsigned int extend_block = 0;
  82         unsigned char sum;
  83         unsigned char test_vector;
  84         int retval;
  85
  86         /*
  87          * EDID device address is 0x50.
  88          * However, if necessary, you must have set upper address
  89          * into E-EDID in I2C device, 0x30.
  90          */
  91
  92         /* Read Extension Flag, Number of 128-byte EDID extension blocks */
  93         exynos_dp_read_byte_from_i2c(dp, I2C_EDID_DEVICE_ADDR,
  94                                 EDID_EXTENSION_FLAG,
  95                                 &extend_block);
  96
  97         if (extend_block > 0) {
  98                 dev_dbg(dp->dev, "EDID data includes a single extension!\n");
  99
 100                 /* Read EDID data */
 101                 retval = exynos_dp_read_bytes_from_i2c(dp, I2C_EDID_DEVICE_ADDR,
 102                                                 EDID_HEADER_PATTERN,
 103                                                 EDID_BLOCK_LENGTH,
 104                                                 &edid[EDID_HEADER_PATTERN]);
 105                 if (retval != 0) {
 106                         dev_err(dp->dev, "EDID Read failed!\n");
 107                         return -EIO;
 108                 }
 109                 sum = exynos_dp_calc_edid_check_sum(edid);
 110                 if (sum != 0) {
 111                         dev_err(dp->dev, "EDID bad checksum!\n");
 112                         return -EIO;
 113                 }
 114
 115                 /* Read additional EDID data */
 116                 retval = exynos_dp_read_bytes_from_i2c(dp,
 117                                 I2C_EDID_DEVICE_ADDR,
 118                                 EDID_BLOCK_LENGTH,
 119                                 EDID_BLOCK_LENGTH,
 120                                 &edid[EDID_BLOCK_LENGTH]);
 121                 if (retval != 0) {
 122                         dev_err(dp->dev, "EDID Read failed!\n");
 123                         return -EIO;
 124                 }
 125                 sum = exynos_dp_calc_edid_check_sum(&edid[EDID_BLOCK_LENGTH]);
 126                 if (sum != 0) {
 127                         dev_err(dp->dev, "EDID bad checksum!\n");
 128                         return -EIO;
 129                 }
 130
 131                 exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_TEST_REQUEST,
 132                                         &test_vector);
 133                 if (test_vector & DPCD_TEST_EDID_READ) {
 134                         exynos_dp_write_byte_to_dpcd(dp,
 135                                 DPCD_ADDR_TEST_EDID_CHECKSUM,
 136                                 edid[EDID_BLOCK_LENGTH + EDID_CHECKSUM]);
 137                         exynos_dp_write_byte_to_dpcd(dp,
 138                                 DPCD_ADDR_TEST_RESPONSE,
 139                                 DPCD_TEST_EDID_CHECKSUM_WRITE);
 140                 }
 141         } else {
 142                 dev_info(dp->dev, "EDID data does not include any extensions.\n");
 143
 144                 /* Read EDID data */
 145                 retval = exynos_dp_read_bytes_from_i2c(dp,
 146                                 I2C_EDID_DEVICE_ADDR,
 147                                 EDID_HEADER_PATTERN,
 148                                 EDID_BLOCK_LENGTH,
 149                                 &edid[EDID_HEADER_PATTERN]);
 150                 if (retval != 0) {
 151                         dev_err(dp->dev, "EDID Read failed!\n");
 152                         return -EIO;
 153                 }
 154                 sum = exynos_dp_calc_edid_check_sum(edid);
 155                 if (sum != 0) {
 156                         dev_err(dp->dev, "EDID bad checksum!\n");
 157                         return -EIO;
 158                 }
 159
 160                 exynos_dp_read_byte_from_dpcd(dp,
 161                         DPCD_ADDR_TEST_REQUEST,
 162                         &test_vector);
 163                 if (test_vector & DPCD_TEST_EDID_READ) {
 164                         exynos_dp_write_byte_to_dpcd(dp,
 165                                 DPCD_ADDR_TEST_EDID_CHECKSUM,
 166                                 edid[EDID_CHECKSUM]);
 167                         exynos_dp_write_byte_to_dpcd(dp,
 168                                 DPCD_ADDR_TEST_RESPONSE,
 169                                 DPCD_TEST_EDID_CHECKSUM_WRITE);
 170                 }
 171         }
 172
 173         dev_err(dp->dev, "EDID Read success!\n");
 174         return 0;
 175 }
 176
 177 static int exynos_dp_handle_edid(struct exynos_dp_device *dp)
 178 {
 179         u8 buf[12];
 180         int i;
 181         int retval;
 182
 183         /* Read DPCD DPCD_ADDR_DPCD_REV~RECEIVE_PORT1_CAP_1 */
 184         exynos_dp_read_bytes_from_dpcd(dp,
 185                 DPCD_ADDR_DPCD_REV,
 186                 12, buf);
 187
 188         /* Read EDID */
 189         for (i = 0; i < 3; i++) {
 190                 retval = exynos_dp_read_edid(dp);
 191                 if (retval == 0)
 192                         break;
 193         }
 194
 195         return retval;
 196 }
 197
 198 static void exynos_dp_enable_rx_to_enhanced_mode(struct exynos_dp_device *dp,
 199                                                 bool enable)
 200 {
 201         u8 data;
 202
 203         exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_LANE_COUNT_SET, &data);
 204
 205         if (enable)
 206                 exynos_dp_write_byte_to_dpcd(dp, DPCD_ADDR_LANE_COUNT_SET,
 207                         DPCD_ENHANCED_FRAME_EN |
 208                         DPCD_LANE_COUNT_SET(data));
 209         else
 210                 exynos_dp_write_byte_to_dpcd(dp, DPCD_ADDR_LANE_COUNT_SET,
 211                         DPCD_LANE_COUNT_SET(data));
 212 }
 213
 214 static int exynos_dp_is_enhanced_mode_available(struct exynos_dp_device *dp)
 215 {
 216         u8 data;
 217         int retval;
 218
 219         exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_MAX_LANE_COUNT, &data);
 220         retval = DPCD_ENHANCED_FRAME_CAP(data);
 221
 222         return retval;
 223 }
 224
 225 static void exynos_dp_set_enhanced_mode(struct exynos_dp_device *dp)
 226 {
 227         u8 data;
 228
 229         data = exynos_dp_is_enhanced_mode_available(dp);
 230         exynos_dp_enable_rx_to_enhanced_mode(dp, data);
 231         exynos_dp_enable_enhanced_mode(dp, data);
 232 }
 233
 234 static void exynos_dp_training_pattern_dis(struct exynos_dp_device *dp)
 235 {
 236         exynos_dp_set_training_pattern(dp, DP_NONE);
 237
 238         exynos_dp_write_byte_to_dpcd(dp,
 239                 DPCD_ADDR_TRAINING_PATTERN_SET,
 240                 DPCD_TRAINING_PATTERN_DISABLED);
 241 }
 242
 243 static void exynos_dp_set_lane_lane_pre_emphasis(struct exynos_dp_device *dp,
 244                                         int pre_emphasis, int lane)
 245 {
 246         switch (lane) {
 247         case 0:
 248                 exynos_dp_set_lane0_pre_emphasis(dp, pre_emphasis);
 249                 break;
 250         case 1:
 251                 exynos_dp_set_lane1_pre_emphasis(dp, pre_emphasis);
 252                 break;
 253
 254         case 2:
 255                 exynos_dp_set_lane2_pre_emphasis(dp, pre_emphasis);
 256                 break;
 257
 258         case 3:
 259                 exynos_dp_set_lane3_pre_emphasis(dp, pre_emphasis);
 260                 break;
 261         }
 262 }
 263
 264 static void exynos_dp_link_start(struct exynos_dp_device *dp)
 265 {
 266         u8 buf[4];
 267         int lane;
 268         int lane_count;
 269
 270         lane_count = dp->link_train.lane_count;
 271
 272         dp->link_train.lt_state = CLOCK_RECOVERY;
 273         dp->link_train.eq_loop = 0;
 274
 275         for (lane = 0; lane < lane_count; lane++)
 276                 dp->link_train.cr_loop[lane] = 0;
 277
 278         /* Set sink to D0 (Sink Not Ready) mode. */
 279         exynos_dp_write_byte_to_dpcd(dp, DPCD_ADDR_SINK_POWER_STATE,
 280                                 DPCD_SET_POWER_STATE_D0);
 281
 282         /* Set link rate and count as you want to establish*/
 283         exynos_dp_set_link_bandwidth(dp, dp->link_train.link_rate);
 284         exynos_dp_set_lane_count(dp, dp->link_train.lane_count);
 285
 286         /* Setup RX configuration */
 287         buf[0] = dp->link_train.link_rate;
 288         buf[1] = dp->link_train.lane_count;
 289         exynos_dp_write_bytes_to_dpcd(dp, DPCD_ADDR_LINK_BW_SET,
 290                                 2, buf);
 291
 292         /* Set TX pre-emphasis to minimum */
 293         for (lane = 0; lane < lane_count; lane++)
 294                 exynos_dp_set_lane_lane_pre_emphasis(dp,
 295                         PRE_EMPHASIS_LEVEL_0, lane);
 296
 297         /* Set training pattern 1 */
 298         exynos_dp_set_training_pattern(dp, TRAINING_PTN1);
 299
 300         /* Set RX training pattern */
 301         exynos_dp_write_byte_to_dpcd(dp,
 302                 DPCD_ADDR_TRAINING_PATTERN_SET,
 303                 DPCD_SCRAMBLING_DISABLED |
 304                 DPCD_TRAINING_PATTERN_1);
 305
 306         for (lane = 0; lane < lane_count; lane++)
 307                 buf[lane] = DPCD_PRE_EMPHASIS_PATTERN2_LEVEL0 |
 308                             DPCD_VOLTAGE_SWING_PATTERN1_LEVEL0;
 309         exynos_dp_write_bytes_to_dpcd(dp,
 310                 DPCD_ADDR_TRAINING_LANE0_SET,
 311                 lane_count, buf);
 312 }
 313
 314 static unsigned char exynos_dp_get_lane_status(u8 link_status[2], int lane)
 315 {
 316         int shift = (lane & 1) * 4;
 317         u8 link_value = link_status[lane>>1];
 318
 319         return (link_value >> shift) & 0xf;
 320 }
 321
 322 static int exynos_dp_clock_recovery_ok(u8 link_status[2], int lane_count)
 323 {
 324         int lane;
 325         u8 lane_status;
 326
 327         for (lane = 0; lane < lane_count; lane++) {
 328                 lane_status = exynos_dp_get_lane_status(link_status, lane);
 329                 if ((lane_status & DPCD_LANE_CR_DONE) == 0)
 330                         return -EINVAL;
 331         }
 332         return 0;
 333 }
 334
 335 static int exynos_dp_channel_eq_ok(u8 link_align[3], int lane_count)
 336 {
 337         int lane;
 338         u8 lane_align;
 339         u8 lane_status;
 340
 341         lane_align = link_align[2];
 342         if ((lane_align & DPCD_INTERLANE_ALIGN_DONE) == 0)
 343                 return -EINVAL;
 344
 345         for (lane = 0; lane < lane_count; lane++) {
 346                 lane_status = exynos_dp_get_lane_status(link_align, lane);
 347                 lane_status &= DPCD_CHANNEL_EQ_BITS;
 348                 if (lane_status != DPCD_CHANNEL_EQ_BITS)
 349                         return -EINVAL;
 350         }
 351
 352         return 0;
 353 }
 354
 355 static unsigned char exynos_dp_get_adjust_request_voltage(u8 adjust_request[2],
 356                                                         int lane)
 357 {
 358         int shift = (lane & 1) * 4;
 359         u8 link_value = adjust_request[lane>>1];
 360
 361         return (link_value >> shift) & 0x3;
 362 }
 363
 364 static unsigned char exynos_dp_get_adjust_request_pre_emphasis(
 365                                         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) & 0xc) >> 2;
 372 }
 373
 374 static void exynos_dp_set_lane_link_training(struct exynos_dp_device *dp,
 375                                         u8 training_lane_set, int lane)
 376 {
 377         switch (lane) {
 378         case 0:
 379                 exynos_dp_set_lane0_link_training(dp, training_lane_set);
 380                 break;
 381         case 1:
 382                 exynos_dp_set_lane1_link_training(dp, training_lane_set);
 383                 break;
 384
 385         case 2:
 386                 exynos_dp_set_lane2_link_training(dp, training_lane_set);
 387                 break;
 388
 389         case 3:
 390                 exynos_dp_set_lane3_link_training(dp, training_lane_set);
 391                 break;
 392         }
 393 }
 394
 395 static unsigned int exynos_dp_get_lane_link_training(
 396                                 struct exynos_dp_device *dp,
 397                                 int lane)
 398 {
 399         u32 reg;
 400
 401         switch (lane) {
 402         case 0:
 403                 reg = exynos_dp_get_lane0_link_training(dp);
 404                 break;
 405         case 1:
 406                 reg = exynos_dp_get_lane1_link_training(dp);
 407                 break;
 408         case 2:
 409                 reg = exynos_dp_get_lane2_link_training(dp);
 410                 break;
 411         case 3:
 412                 reg = exynos_dp_get_lane3_link_training(dp);
 413                 break;
 414         default:
 415                 WARN_ON(1);
 416                 return 0;
 417         }
 418
 419         return reg;
 420 }
 421
 422 static void exynos_dp_reduce_link_rate(struct exynos_dp_device *dp)
 423 {
 424         exynos_dp_training_pattern_dis(dp);
 425         exynos_dp_set_enhanced_mode(dp);
 426
 427         dp->link_train.lt_state = FAILED;
 428 }
 429
 430 static int exynos_dp_process_clock_recovery(struct exynos_dp_device *dp)
 431 {
 432         u8 link_status[2];
 433         int lane;
 434         int lane_count;
 435
 436         u8 adjust_request[2];
 437         u8 voltage_swing;
 438         u8 pre_emphasis;
 439         u8 training_lane;
 440
 441         usleep_range(100, 101);
 442
 443         lane_count = dp->link_train.lane_count;
 444
 445         exynos_dp_read_bytes_from_dpcd(dp, DPCD_ADDR_LANE0_1_STATUS,
 446                                 2, link_status);
 447
 448         if (exynos_dp_clock_recovery_ok(link_status, lane_count) == 0) {
 449                 /* set training pattern 2 for EQ */
 450                 exynos_dp_set_training_pattern(dp, TRAINING_PTN2);
 451
 452                 for (lane = 0; lane < lane_count; lane++) {
 453                         exynos_dp_read_bytes_from_dpcd(dp,
 454                                         DPCD_ADDR_ADJUST_REQUEST_LANE0_1,
 455                                         2, adjust_request);
 456                         voltage_swing = exynos_dp_get_adjust_request_voltage(
 457                                                         adjust_request, lane);
 458                         pre_emphasis = exynos_dp_get_adjust_request_pre_emphasis(
 459                                                         adjust_request, lane);
 460                         training_lane = DPCD_VOLTAGE_SWING_SET(voltage_swing) |
 461                                         DPCD_PRE_EMPHASIS_SET(pre_emphasis);
 462
 463                         if (voltage_swing == VOLTAGE_LEVEL_3)
 464                                 training_lane |= DPCD_MAX_SWING_REACHED;
 465                         if (pre_emphasis == PRE_EMPHASIS_LEVEL_3)
 466                                 training_lane |= DPCD_MAX_PRE_EMPHASIS_REACHED;
 467
 468                         dp->link_train.training_lane[lane] = training_lane;
 469
 470                         exynos_dp_set_lane_link_training(dp,
 471                                 dp->link_train.training_lane[lane],
 472                                 lane);
 473                 }
 474
 475                 exynos_dp_write_byte_to_dpcd(dp,
 476                         DPCD_ADDR_TRAINING_PATTERN_SET,
 477                         DPCD_SCRAMBLING_DISABLED |
 478                         DPCD_TRAINING_PATTERN_2);
 479
 480                 exynos_dp_write_bytes_to_dpcd(dp,
 481                         DPCD_ADDR_TRAINING_LANE0_SET,
 482                         lane_count,
 483                         dp->link_train.training_lane);
 484
 485                 dev_info(dp->dev, "Link Training Clock Recovery success\n");
 486                 dp->link_train.lt_state = EQUALIZER_TRAINING;
 487         } else {
 488                 for (lane = 0; lane < lane_count; lane++) {
 489                         training_lane = exynos_dp_get_lane_link_training(
 490                                                         dp, lane);
 491                         exynos_dp_read_bytes_from_dpcd(dp,
 492                                         DPCD_ADDR_ADJUST_REQUEST_LANE0_1,
 493                                         2, adjust_request);
 494                         voltage_swing = exynos_dp_get_adjust_request_voltage(
 495                                                         adjust_request, lane);
 496                         pre_emphasis = exynos_dp_get_adjust_request_pre_emphasis(
 497                                                         adjust_request, lane);
 498
 499                         if (voltage_swing == VOLTAGE_LEVEL_3 ||
 500                             pre_emphasis == PRE_EMPHASIS_LEVEL_3) {
 501                                 dev_err(dp->dev, "voltage or pre emphasis reached max level\n");
 502                                 goto reduce_link_rate;
 503                         }
 504
 505                         if ((DPCD_VOLTAGE_SWING_GET(training_lane) ==
 506                                         voltage_swing) &&
 507                            (DPCD_PRE_EMPHASIS_GET(training_lane) ==
 508                                         pre_emphasis)) {
 509                                 dp->link_train.cr_loop[lane]++;
 510                                 if (dp->link_train.cr_loop[lane] == MAX_CR_LOOP) {
 511                                         dev_err(dp->dev, "CR Max loop\n");
 512                                         goto reduce_link_rate;
 513                                 }
 514                         }
 515
 516                         training_lane = DPCD_VOLTAGE_SWING_SET(voltage_swing) |
 517                                         DPCD_PRE_EMPHASIS_SET(pre_emphasis);
 518
 519                         if (voltage_swing == VOLTAGE_LEVEL_3)
 520                                 training_lane |= DPCD_MAX_SWING_REACHED;
 521                         if (pre_emphasis == PRE_EMPHASIS_LEVEL_3)
 522                                 training_lane |= DPCD_MAX_PRE_EMPHASIS_REACHED;
 523
 524                         dp->link_train.training_lane[lane] = training_lane;
 525
 526                         exynos_dp_set_lane_link_training(dp,
 527                                 dp->link_train.training_lane[lane], lane);
 528                 }
 529
 530                 exynos_dp_write_bytes_to_dpcd(dp,
 531                         DPCD_ADDR_TRAINING_LANE0_SET,
 532                         lane_count,
 533                         dp->link_train.training_lane);
 534         }
 535
 536         return 0;
 537
 538 reduce_link_rate:
 539         exynos_dp_reduce_link_rate(dp);
 540         return -EIO;
 541 }
 542
 543 static int exynos_dp_process_equalizer_training(struct exynos_dp_device *dp)
 544 {
 545         u8 link_status[2];
 546         u8 link_align[3];
 547         int lane;
 548         int lane_count;
 549         u32 reg;
 550
 551         u8 adjust_request[2];
 552         u8 voltage_swing;
 553         u8 pre_emphasis;
 554         u8 training_lane;
 555
 556         usleep_range(400, 401);
 557
 558         lane_count = dp->link_train.lane_count;
 559
 560         exynos_dp_read_bytes_from_dpcd(dp, DPCD_ADDR_LANE0_1_STATUS,
 561                                 2, link_status);
 562
 563         if (exynos_dp_clock_recovery_ok(link_status, lane_count) == 0) {
 564                 link_align[0] = link_status[0];
 565                 link_align[1] = link_status[1];
 566
 567                 exynos_dp_read_byte_from_dpcd(dp,
 568                         DPCD_ADDR_LANE_ALIGN_STATUS_UPDATED,
 569                         &link_align[2]);
 570
 571                 for (lane = 0; lane < lane_count; lane++) {
 572                         exynos_dp_read_bytes_from_dpcd(dp,
 573                                         DPCD_ADDR_ADJUST_REQUEST_LANE0_1,
 574                                         2, adjust_request);
 575                         voltage_swing = exynos_dp_get_adjust_request_voltage(
 576                                                         adjust_request, lane);
 577                         pre_emphasis = exynos_dp_get_adjust_request_pre_emphasis(
 578                                                         adjust_request, lane);
 579                         training_lane = DPCD_VOLTAGE_SWING_SET(voltage_swing) |
 580                                         DPCD_PRE_EMPHASIS_SET(pre_emphasis);
 581
 582                         if (voltage_swing == VOLTAGE_LEVEL_3)
 583                                 training_lane |= DPCD_MAX_SWING_REACHED;
 584                         if (pre_emphasis == PRE_EMPHASIS_LEVEL_3)
 585                                 training_lane |= DPCD_MAX_PRE_EMPHASIS_REACHED;
 586
 587                         dp->link_train.training_lane[lane] = training_lane;
 588                 }
 589
 590                 if (exynos_dp_channel_eq_ok(link_align, lane_count) == 0) {
 591                         /* traing pattern Set to Normal */
 592                         exynos_dp_training_pattern_dis(dp);
 593
 594                         dev_info(dp->dev, "Link Training success!\n");
 595
 596                         exynos_dp_get_link_bandwidth(dp, &reg);
 597                         dp->link_train.link_rate = reg;
 598                         dev_dbg(dp->dev, "final bandwidth = %.2x\n",
 599                                 dp->link_train.link_rate);
 600
 601                         exynos_dp_get_lane_count(dp, &reg);
 602                         dp->link_train.lane_count = reg;
 603                         dev_dbg(dp->dev, "final lane count = %.2x\n",
 604                                 dp->link_train.lane_count);
 605
 606                         /* set enhanced mode if available */
 607                         exynos_dp_set_enhanced_mode(dp);
 608                         dp->link_train.lt_state = FINISHED;
 609                 } else {
 610                         /* not all locked */
 611                         dp->link_train.eq_loop++;
 612
 613                         if (dp->link_train.eq_loop > MAX_EQ_LOOP) {
 614                                 dev_err(dp->dev, "EQ Max loop\n");
 615                                 goto reduce_link_rate;
 616                         }
 617
 618                         for (lane = 0; lane < lane_count; lane++)
 619                                 exynos_dp_set_lane_link_training(dp,
 620                                         dp->link_train.training_lane[lane],
 621                                         lane);
 622
 623                         exynos_dp_write_bytes_to_dpcd(dp,
 624                                 DPCD_ADDR_TRAINING_LANE0_SET,
 625                                 lane_count,
 626                                 dp->link_train.training_lane);
 627                 }
 628         } else {
 629                 goto reduce_link_rate;
 630         }
 631
 632         return 0;
 633
 634 reduce_link_rate:
 635         exynos_dp_reduce_link_rate(dp);
 636         return -EIO;
 637 }
 638
 639 static void exynos_dp_get_max_rx_bandwidth(struct exynos_dp_device *dp,
 640                                         u8 *bandwidth)
 641 {
 642         u8 data;
 643
 644         /*
 645          * For DP rev.1.1, Maximum link rate of Main Link lanes
 646          * 0x06 = 1.62 Gbps, 0x0a = 2.7 Gbps
 647          */
 648         exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_MAX_LINK_RATE, &data);
 649         *bandwidth = data;
 650 }
 651
 652 static void exynos_dp_get_max_rx_lane_count(struct exynos_dp_device *dp,
 653                                         u8 *lane_count)
 654 {
 655         u8 data;
 656
 657         /*
 658          * For DP rev.1.1, Maximum number of Main Link lanes
 659          * 0x01 = 1 lane, 0x02 = 2 lanes, 0x04 = 4 lanes
 660          */
 661         exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_MAX_LANE_COUNT, &data);
 662         *lane_count = DPCD_MAX_LANE_COUNT(data);
 663 }
 664
 665 static void exynos_dp_init_training(struct exynos_dp_device *dp,
 666                         enum link_lane_count_type max_lane,
 667                         enum link_rate_type max_rate)
 668 {
 669         /*
 670          * MACRO_RST must be applied after the PLL_LOCK to avoid
 671          * the DP inter pair skew issue for at least 10 us
 672          */
 673         exynos_dp_reset_macro(dp);
 674
 675         /* Initialize by reading RX's DPCD */
 676         exynos_dp_get_max_rx_bandwidth(dp, &dp->link_train.link_rate);
 677         exynos_dp_get_max_rx_lane_count(dp, &dp->link_train.lane_count);
 678
 679         if ((dp->link_train.link_rate != LINK_RATE_1_62GBPS) &&
 680            (dp->link_train.link_rate != LINK_RATE_2_70GBPS)) {
 681                 dev_err(dp->dev, "Rx Max Link Rate is abnormal :%x !\n",
 682                         dp->link_train.link_rate);
 683                 dp->link_train.link_rate = LINK_RATE_1_62GBPS;
 684         }
 685
 686         if (dp->link_train.lane_count == 0) {
 687                 dev_err(dp->dev, "Rx Max Lane count is abnormal :%x !\n",
 688                         dp->link_train.lane_count);
 689                 dp->link_train.lane_count = (u8)LANE_COUNT1;
 690         }
 691
 692         /* Setup TX lane count & rate */
 693         if (dp->link_train.lane_count > max_lane)
 694                 dp->link_train.lane_count = max_lane;
 695         if (dp->link_train.link_rate > max_rate)
 696                 dp->link_train.link_rate = max_rate;
 697
 698         /* All DP analog module power up */
 699         exynos_dp_set_analog_power_down(dp, POWER_ALL, 0);
 700 }
 701
 702 static int exynos_dp_sw_link_training(struct exynos_dp_device *dp)
 703 {
 704         int retval = 0;
 705         int training_finished = 0;
 706
 707         dp->link_train.lt_state = START;
 708
 709         /* Process here */
 710         while (!training_finished) {
 711                 switch (dp->link_train.lt_state) {
 712                 case START:
 713                         exynos_dp_link_start(dp);
 714                         break;
 715                 case CLOCK_RECOVERY:
 716                         retval = exynos_dp_process_clock_recovery(dp);
 717                         if (retval)
 718                                 dev_err(dp->dev, "LT CR failed!\n");
 719                         break;
 720                 case EQUALIZER_TRAINING:
 721                         retval = exynos_dp_process_equalizer_training(dp);
 722                         if (retval)
 723                                 dev_err(dp->dev, "LT EQ failed!\n");
 724                         break;
 725                 case FINISHED:
 726                         training_finished = 1;
 727                         break;
 728                 case FAILED:
 729                         return -EREMOTEIO;
 730                 }
 731         }
 732
 733         return retval;
 734 }
 735
 736 static int exynos_dp_set_link_train(struct exynos_dp_device *dp,
 737                                 u32 count,
 738                                 u32 bwtype)
 739 {
 740         int i;
 741         int retval;
 742
 743         for (i = 0; i < DP_TIMEOUT_LOOP_COUNT; i++) {
 744                 exynos_dp_init_training(dp, count, bwtype);
 745                 retval = exynos_dp_sw_link_training(dp);
 746                 if (retval == 0)
 747                         break;
 748
 749                 usleep_range(100, 110);
 750         }
 751
 752         return retval;
 753 }
 754
 755 static int exynos_dp_config_video(struct exynos_dp_device *dp,
 756                         struct video_info *video_info)
 757 {
 758         int retval = 0;
 759         int timeout_loop = 0;
 760         int done_count = 0;
 761
 762         exynos_dp_config_video_slave_mode(dp, video_info);
 763
 764         exynos_dp_set_video_color_format(dp, video_info->color_depth,
 765                         video_info->color_space,
 766                         video_info->dynamic_range,
 767                         video_info->ycbcr_coeff);
 768
 769         if (exynos_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
 770                 dev_err(dp->dev, "PLL is not locked yet.\n");
 771                 return -EINVAL;
 772         }
 773
 774         for (;;) {
 775                 timeout_loop++;
 776                 if (exynos_dp_is_slave_video_stream_clock_on(dp) == 0)
 777                         break;
 778                 if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
 779                         dev_err(dp->dev, "Timeout of video streamclk ok\n");
 780                         return -ETIMEDOUT;
 781                 }
 782
 783                 usleep_range(1, 2);
 784         }
 785
 786         /* Set to use the register calculated M/N video */
 787         exynos_dp_set_video_cr_mn(dp, CALCULATED_M, 0, 0);
 788
 789         /* For video bist, Video timing must be generated by register */
 790         exynos_dp_set_video_timing_mode(dp, VIDEO_TIMING_FROM_CAPTURE);
 791
 792         /* Disable video mute */
 793         exynos_dp_enable_video_mute(dp, 0);
 794
 795         /* Configure video slave mode */
 796         exynos_dp_enable_video_master(dp, 0);
 797
 798         /* Enable video */
 799         exynos_dp_start_video(dp);
 800
 801         timeout_loop = 0;
 802
 803         for (;;) {
 804                 timeout_loop++;
 805                 if (exynos_dp_is_video_stream_on(dp) == 0) {
 806                         done_count++;
 807                         if (done_count > 10)
 808                                 break;
 809                 } else if (done_count) {
 810                         done_count = 0;
 811                 }
 812                 if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
 813                         dev_err(dp->dev, "Timeout of video streamclk ok\n");
 814                         return -ETIMEDOUT;
 815                 }
 816
 817                 usleep_range(1000, 1001);
 818         }
 819
 820         if (retval != 0)
 821                 dev_err(dp->dev, "Video stream is not detected!\n");
 822
 823         return retval;
 824 }
 825
 826 static void exynos_dp_enable_scramble(struct exynos_dp_device *dp, bool enable)
 827 {
 828         u8 data;
 829
 830         if (enable) {
 831                 exynos_dp_enable_scrambling(dp);
 832
 833                 exynos_dp_read_byte_from_dpcd(dp,
 834                         DPCD_ADDR_TRAINING_PATTERN_SET,
 835                         &data);
 836                 exynos_dp_write_byte_to_dpcd(dp,
 837                         DPCD_ADDR_TRAINING_PATTERN_SET,
 838                         (u8)(data & ~DPCD_SCRAMBLING_DISABLED));
 839         } else {
 840                 exynos_dp_disable_scrambling(dp);
 841
 842                 exynos_dp_read_byte_from_dpcd(dp,
 843                         DPCD_ADDR_TRAINING_PATTERN_SET,
 844                         &data);
 845                 exynos_dp_write_byte_to_dpcd(dp,
 846                         DPCD_ADDR_TRAINING_PATTERN_SET,
 847                         (u8)(data | DPCD_SCRAMBLING_DISABLED));
 848         }
 849 }
 850
 851 static irqreturn_t exynos_dp_irq_handler(int irq, void *arg)
 852 {
 853         struct exynos_dp_device *dp = arg;
 854
 855         dev_err(dp->dev, "exynos_dp_irq_handler\n");
 856         return IRQ_HANDLED;
 857 }
 858
 859 static int __devinit exynos_dp_probe(struct platform_device *pdev)
 860 {
 861         struct resource *res;
 862         struct exynos_dp_device *dp;
 863         struct exynos_dp_platdata *pdata;
 864
 865         int ret = 0;
 866
 867         pdata = pdev->dev.platform_data;
 868         if (!pdata) {
 869                 dev_err(&pdev->dev, "no platform data\n");
 870                 return -EINVAL;
 871         }
 872
 873         dp = devm_kzalloc(&pdev->dev, sizeof(struct exynos_dp_device),
 874                                 GFP_KERNEL);
 875         if (!dp) {
 876                 dev_err(&pdev->dev, "no memory for device data\n");
 877                 return -ENOMEM;
 878         }
 879
 880         dp->dev = &pdev->dev;
 881
 882         dp->clock = devm_clk_get(&pdev->dev, "dp");
 883         if (IS_ERR(dp->clock)) {
 884                 dev_err(&pdev->dev, "failed to get clock\n");
 885                 return PTR_ERR(dp->clock);
 886         }
 887
 888         clk_prepare_enable(dp->clock);
 889
 890         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 891
 892         dp->reg_base = devm_request_and_ioremap(&pdev->dev, res);
 893         if (!dp->reg_base) {
 894                 dev_err(&pdev->dev, "failed to ioremap\n");
 895                 return -ENOMEM;
 896         }
 897
 898         dp->irq = platform_get_irq(pdev, 0);
 899         if (!dp->irq) {
 900                 dev_err(&pdev->dev, "failed to get irq\n");
 901                 return -ENODEV;
 902         }
 903
 904         ret = devm_request_irq(&pdev->dev, dp->irq, exynos_dp_irq_handler, 0,
 905                                 "exynos-dp", dp);
 906         if (ret) {
 907                 dev_err(&pdev->dev, "failed to request irq\n");
 908                 return ret;
 909         }
 910
 911         dp->video_info = pdata->video_info;
 912         if (pdata->phy_init)
 913                 pdata->phy_init();
 914
 915         exynos_dp_init_dp(dp);
 916
 917         ret = exynos_dp_detect_hpd(dp);
 918         if (ret) {
 919                 dev_err(&pdev->dev, "unable to detect hpd\n");
 920                 return ret;
 921         }
 922
 923         exynos_dp_handle_edid(dp);
 924
 925         ret = exynos_dp_set_link_train(dp, dp->video_info->lane_count,
 926                                 dp->video_info->link_rate);
 927         if (ret) {
 928                 dev_err(&pdev->dev, "unable to do link train\n");
 929                 return ret;
 930         }
 931
 932         exynos_dp_enable_scramble(dp, 1);
 933         exynos_dp_enable_rx_to_enhanced_mode(dp, 1);
 934         exynos_dp_enable_enhanced_mode(dp, 1);
 935
 936         exynos_dp_set_lane_count(dp, dp->video_info->lane_count);
 937         exynos_dp_set_link_bandwidth(dp, dp->video_info->link_rate);
 938
 939         exynos_dp_init_video(dp);
 940         ret = exynos_dp_config_video(dp, dp->video_info);
 941         if (ret) {
 942                 dev_err(&pdev->dev, "unable to config video\n");
 943                 return ret;
 944         }
 945
 946         platform_set_drvdata(pdev, dp);
 947
 948         return 0;
 949 }
 950
 951 static int __devexit exynos_dp_remove(struct platform_device *pdev)
 952 {
 953         struct exynos_dp_platdata *pdata = pdev->dev.platform_data;
 954         struct exynos_dp_device *dp = platform_get_drvdata(pdev);
 955
 956         if (pdata && pdata->phy_exit)
 957                 pdata->phy_exit();
 958
 959         clk_disable_unprepare(dp->clock);
 960
 961         return 0;
 962 }
 963
 964 #ifdef CONFIG_PM_SLEEP
 965 static int exynos_dp_suspend(struct device *dev)
 966 {
 967         struct platform_device *pdev = to_platform_device(dev);
 968         struct exynos_dp_platdata *pdata = pdev->dev.platform_data;
 969         struct exynos_dp_device *dp = platform_get_drvdata(pdev);
 970
 971         if (pdata && pdata->phy_exit)
 972                 pdata->phy_exit();
 973
 974         clk_disable_unprepare(dp->clock);
 975
 976         return 0;
 977 }
 978
 979 static int exynos_dp_resume(struct device *dev)
 980 {
 981         struct platform_device *pdev = to_platform_device(dev);
 982         struct exynos_dp_platdata *pdata = pdev->dev.platform_data;
 983         struct exynos_dp_device *dp = platform_get_drvdata(pdev);
 984
 985         if (pdata && pdata->phy_init)
 986                 pdata->phy_init();
 987
 988         clk_prepare_enable(dp->clock);
 989
 990         exynos_dp_init_dp(dp);
 991
 992         exynos_dp_detect_hpd(dp);
 993         exynos_dp_handle_edid(dp);
 994
 995         exynos_dp_set_link_train(dp, dp->video_info->lane_count,
 996                                 dp->video_info->link_rate);
 997
 998         exynos_dp_enable_scramble(dp, 1);
 999         exynos_dp_enable_rx_to_enhanced_mode(dp, 1);
1000         exynos_dp_enable_enhanced_mode(dp, 1);
1001
1002         exynos_dp_set_lane_count(dp, dp->video_info->lane_count);
1003         exynos_dp_set_link_bandwidth(dp, dp->video_info->link_rate);
1004
1005         exynos_dp_init_video(dp);
1006         exynos_dp_config_video(dp, dp->video_info);
1007
1008         return 0;
1009 }
1010 #endif
1011
1012 static const struct dev_pm_ops exynos_dp_pm_ops = {
1013         SET_SYSTEM_SLEEP_PM_OPS(exynos_dp_suspend, exynos_dp_resume)
1014 };
1015
1016 static struct platform_driver exynos_dp_driver = {
1017         .probe          = exynos_dp_probe,
1018         .remove         = __devexit_p(exynos_dp_remove),
1019         .driver         = {
1020                 .name   = "exynos-dp",
1021                 .owner  = THIS_MODULE,
1022                 .pm     = &exynos_dp_pm_ops,
1023         },
1024 };
1025
1026 module_platform_driver(exynos_dp_driver);
1027
1028 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
1029 MODULE_DESCRIPTION("Samsung SoC DP Driver");
1030 MODULE_LICENSE("GPL");