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
  23 #include <video/exynos_dp.h>
  24
  25 #include "exynos_dp_core.h"
  26
  27 static int exynos_dp_init_dp(struct exynos_dp_device *dp)
  28 {
  29         exynos_dp_reset(dp);
  30
  31         exynos_dp_swreset(dp);
  32
  33         exynos_dp_init_analog_param(dp);
  34         exynos_dp_init_interrupt(dp);
  35
  36         /* SW defined function Normal operation */
  37         exynos_dp_enable_sw_function(dp);
  38
  39         exynos_dp_config_interrupt(dp);
  40         exynos_dp_init_analog_func(dp);
  41
  42         exynos_dp_init_hpd(dp);
  43         exynos_dp_init_aux(dp);
  44
  45         return 0;
  46 }
  47
  48 static int exynos_dp_detect_hpd(struct exynos_dp_device *dp)
  49 {
  50         int timeout_loop = 0;
  51
  52         while (exynos_dp_get_plug_in_status(dp) != 0) {
  53                 timeout_loop++;
  54                 if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
  55                         dev_err(dp->dev, "failed to get hpd plug status\n");
  56                         return -ETIMEDOUT;
  57                 }
  58                 usleep_range(10, 11);
  59         }
  60
  61         return 0;
  62 }
  63
  64 static unsigned char exynos_dp_calc_edid_check_sum(unsigned char *edid_data)
  65 {
  66         int i;
  67         unsigned char sum = 0;
  68
  69         for (i = 0; i < EDID_BLOCK_LENGTH; i++)
  70                 sum = sum + edid_data[i];
  71
  72         return sum;
  73 }
  74
  75 static int exynos_dp_read_edid(struct exynos_dp_device *dp)
  76 {
  77         unsigned char edid[EDID_BLOCK_LENGTH * 2];
  78         unsigned int extend_block = 0;
  79         unsigned char sum;
  80         unsigned char test_vector;
  81         int retval;
  82
  83         /*
  84          * EDID device address is 0x50.
  85          * However, if necessary, you must have set upper address
  86          * into E-EDID in I2C device, 0x30.
  87          */
  88
  89         /* Read Extension Flag, Number of 128-byte EDID extension blocks */
  90         retval = exynos_dp_read_byte_from_i2c(dp, I2C_EDID_DEVICE_ADDR,
  91                                 EDID_EXTENSION_FLAG,
  92                                 &extend_block);
  93         if (retval)
  94                 return retval;
  95
  96         if (extend_block > 0) {
  97                 dev_dbg(dp->dev, "EDID data includes a single extension!\n");
  98
  99                 /* Read EDID data */
 100                 retval = exynos_dp_read_bytes_from_i2c(dp, I2C_EDID_DEVICE_ADDR,
 101                                                 EDID_HEADER_PATTERN,
 102                                                 EDID_BLOCK_LENGTH,
 103                                                 &edid[EDID_HEADER_PATTERN]);
 104                 if (retval != 0) {
 105                         dev_err(dp->dev, "EDID Read failed!\n");
 106                         return -EIO;
 107                 }
 108                 sum = exynos_dp_calc_edid_check_sum(edid);
 109                 if (sum != 0) {
 110                         dev_err(dp->dev, "EDID bad checksum!\n");
 111                         return -EIO;
 112                 }
 113
 114                 /* Read additional EDID data */
 115                 retval = exynos_dp_read_bytes_from_i2c(dp,
 116                                 I2C_EDID_DEVICE_ADDR,
 117                                 EDID_BLOCK_LENGTH,
 118                                 EDID_BLOCK_LENGTH,
 119                                 &edid[EDID_BLOCK_LENGTH]);
 120                 if (retval != 0) {
 121                         dev_err(dp->dev, "EDID Read failed!\n");
 122                         return -EIO;
 123                 }
 124                 sum = exynos_dp_calc_edid_check_sum(&edid[EDID_BLOCK_LENGTH]);
 125                 if (sum != 0) {
 126                         dev_err(dp->dev, "EDID bad checksum!\n");
 127                         return -EIO;
 128                 }
 129
 130                 exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_TEST_REQUEST,
 131                                         &test_vector);
 132                 if (test_vector & DPCD_TEST_EDID_READ) {
 133                         exynos_dp_write_byte_to_dpcd(dp,
 134                                 DPCD_ADDR_TEST_EDID_CHECKSUM,
 135                                 edid[EDID_BLOCK_LENGTH + EDID_CHECKSUM]);
 136                         exynos_dp_write_byte_to_dpcd(dp,
 137                                 DPCD_ADDR_TEST_RESPONSE,
 138                                 DPCD_TEST_EDID_CHECKSUM_WRITE);
 139                 }
 140         } else {
 141                 dev_info(dp->dev, "EDID data does not include any extensions.\n");
 142
 143                 /* Read EDID data */
 144                 retval = exynos_dp_read_bytes_from_i2c(dp,
 145                                 I2C_EDID_DEVICE_ADDR,
 146                                 EDID_HEADER_PATTERN,
 147                                 EDID_BLOCK_LENGTH,
 148                                 &edid[EDID_HEADER_PATTERN]);
 149                 if (retval != 0) {
 150                         dev_err(dp->dev, "EDID Read failed!\n");
 151                         return -EIO;
 152                 }
 153                 sum = exynos_dp_calc_edid_check_sum(edid);
 154                 if (sum != 0) {
 155                         dev_err(dp->dev, "EDID bad checksum!\n");
 156                         return -EIO;
 157                 }
 158
 159                 exynos_dp_read_byte_from_dpcd(dp,
 160                         DPCD_ADDR_TEST_REQUEST,
 161                         &test_vector);
 162                 if (test_vector & DPCD_TEST_EDID_READ) {
 163                         exynos_dp_write_byte_to_dpcd(dp,
 164                                 DPCD_ADDR_TEST_EDID_CHECKSUM,
 165                                 edid[EDID_CHECKSUM]);
 166                         exynos_dp_write_byte_to_dpcd(dp,
 167                                 DPCD_ADDR_TEST_RESPONSE,
 168                                 DPCD_TEST_EDID_CHECKSUM_WRITE);
 169                 }
 170         }
 171
 172         dev_err(dp->dev, "EDID Read success!\n");
 173         return 0;
 174 }
 175
 176 static int exynos_dp_handle_edid(struct exynos_dp_device *dp)
 177 {
 178         u8 buf[12];
 179         int i;
 180         int retval;
 181
 182         /* Read DPCD DPCD_ADDR_DPCD_REV~RECEIVE_PORT1_CAP_1 */
 183         retval = exynos_dp_read_bytes_from_dpcd(dp, DPCD_ADDR_DPCD_REV,
 184                                 12, buf);
 185         if (retval)
 186                 return retval;
 187
 188         /* Read EDID */
 189         for (i = 0; i < 3; i++) {
 190                 retval = exynos_dp_read_edid(dp);
 191                 if (!retval)
 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 int exynos_dp_link_start(struct exynos_dp_device *dp)
 265 {
 266         u8 buf[4];
 267         int lane, lane_count, pll_tries, retval;
 268
 269         lane_count = dp->link_train.lane_count;
 270
 271         dp->link_train.lt_state = CLOCK_RECOVERY;
 272         dp->link_train.eq_loop = 0;
 273
 274         for (lane = 0; lane < lane_count; lane++)
 275                 dp->link_train.cr_loop[lane] = 0;
 276
 277         /* Set link rate and count as you want to establish*/
 278         exynos_dp_set_link_bandwidth(dp, dp->link_train.link_rate);
 279         exynos_dp_set_lane_count(dp, dp->link_train.lane_count);
 280
 281         /* Setup RX configuration */
 282         buf[0] = dp->link_train.link_rate;
 283         buf[1] = dp->link_train.lane_count;
 284         retval = exynos_dp_write_bytes_to_dpcd(dp, DPCD_ADDR_LINK_BW_SET,
 285                                 2, buf);
 286         if (retval)
 287                 return retval;
 288
 289         /* Set TX pre-emphasis to minimum */
 290         for (lane = 0; lane < lane_count; lane++)
 291                 exynos_dp_set_lane_lane_pre_emphasis(dp,
 292                         PRE_EMPHASIS_LEVEL_0, lane);
 293
 294         /* Wait for PLL lock */
 295         pll_tries = 0;
 296         while (exynos_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
 297                 if (pll_tries == DP_TIMEOUT_LOOP_COUNT) {
 298                         dev_err(dp->dev, "Wait for PLL lock timed out\n");
 299                         return -ETIMEDOUT;
 300                 }
 301
 302                 pll_tries++;
 303                 usleep_range(90, 120);
 304         }
 305
 306         /* Set training pattern 1 */
 307         exynos_dp_set_training_pattern(dp, TRAINING_PTN1);
 308
 309         /* Set RX training pattern */
 310         retval = exynos_dp_write_byte_to_dpcd(dp,
 311                         DPCD_ADDR_TRAINING_PATTERN_SET,
 312                         DPCD_SCRAMBLING_DISABLED | DPCD_TRAINING_PATTERN_1);
 313         if (retval)
 314                 return retval;
 315
 316         for (lane = 0; lane < lane_count; lane++)
 317                 buf[lane] = DPCD_PRE_EMPHASIS_PATTERN2_LEVEL0 |
 318                             DPCD_VOLTAGE_SWING_PATTERN1_LEVEL0;
 319
 320         retval = exynos_dp_write_bytes_to_dpcd(dp, DPCD_ADDR_TRAINING_LANE0_SET,
 321                         lane_count, buf);
 322
 323         return retval;
 324 }
 325
 326 static unsigned char exynos_dp_get_lane_status(u8 link_status[2], int lane)
 327 {
 328         int shift = (lane & 1) * 4;
 329         u8 link_value = link_status[lane>>1];
 330
 331         return (link_value >> shift) & 0xf;
 332 }
 333
 334 static int exynos_dp_clock_recovery_ok(u8 link_status[2], int lane_count)
 335 {
 336         int lane;
 337         u8 lane_status;
 338
 339         for (lane = 0; lane < lane_count; lane++) {
 340                 lane_status = exynos_dp_get_lane_status(link_status, lane);
 341                 if ((lane_status & DPCD_LANE_CR_DONE) == 0)
 342                         return -EINVAL;
 343         }
 344         return 0;
 345 }
 346
 347 static int exynos_dp_channel_eq_ok(u8 link_status[2], u8 link_align,
 348                                 int lane_count)
 349 {
 350         int lane;
 351         u8 lane_status;
 352
 353         if ((link_align & DPCD_INTERLANE_ALIGN_DONE) == 0)
 354                 return -EINVAL;
 355
 356         for (lane = 0; lane < lane_count; lane++) {
 357                 lane_status = exynos_dp_get_lane_status(link_status, lane);
 358                 lane_status &= DPCD_CHANNEL_EQ_BITS;
 359                 if (lane_status != DPCD_CHANNEL_EQ_BITS)
 360                         return -EINVAL;
 361         }
 362
 363         return 0;
 364 }
 365
 366 static unsigned char exynos_dp_get_adjust_request_voltage(u8 adjust_request[2],
 367                                                         int lane)
 368 {
 369         int shift = (lane & 1) * 4;
 370         u8 link_value = adjust_request[lane>>1];
 371
 372         return (link_value >> shift) & 0x3;
 373 }
 374
 375 static unsigned char exynos_dp_get_adjust_request_pre_emphasis(
 376                                         u8 adjust_request[2],
 377                                         int lane)
 378 {
 379         int shift = (lane & 1) * 4;
 380         u8 link_value = adjust_request[lane>>1];
 381
 382         return ((link_value >> shift) & 0xc) >> 2;
 383 }
 384
 385 static void exynos_dp_set_lane_link_training(struct exynos_dp_device *dp,
 386                                         u8 training_lane_set, int lane)
 387 {
 388         switch (lane) {
 389         case 0:
 390                 exynos_dp_set_lane0_link_training(dp, training_lane_set);
 391                 break;
 392         case 1:
 393                 exynos_dp_set_lane1_link_training(dp, training_lane_set);
 394                 break;
 395
 396         case 2:
 397                 exynos_dp_set_lane2_link_training(dp, training_lane_set);
 398                 break;
 399
 400         case 3:
 401                 exynos_dp_set_lane3_link_training(dp, training_lane_set);
 402                 break;
 403         }
 404 }
 405
 406 static unsigned int exynos_dp_get_lane_link_training(
 407                                 struct exynos_dp_device *dp,
 408                                 int lane)
 409 {
 410         u32 reg;
 411
 412         switch (lane) {
 413         case 0:
 414                 reg = exynos_dp_get_lane0_link_training(dp);
 415                 break;
 416         case 1:
 417                 reg = exynos_dp_get_lane1_link_training(dp);
 418                 break;
 419         case 2:
 420                 reg = exynos_dp_get_lane2_link_training(dp);
 421                 break;
 422         case 3:
 423                 reg = exynos_dp_get_lane3_link_training(dp);
 424                 break;
 425         default:
 426                 WARN_ON(1);
 427                 return 0;
 428         }
 429
 430         return reg;
 431 }
 432
 433 static void exynos_dp_reduce_link_rate(struct exynos_dp_device *dp)
 434 {
 435         exynos_dp_training_pattern_dis(dp);
 436         exynos_dp_set_enhanced_mode(dp);
 437
 438         dp->link_train.lt_state = FAILED;
 439 }
 440
 441 static void exynos_dp_get_adjust_training_lane(struct exynos_dp_device *dp,
 442                                         u8 adjust_request[2])
 443 {
 444         int lane, lane_count;
 445         u8 voltage_swing, pre_emphasis, training_lane;
 446
 447         lane_count = dp->link_train.lane_count;
 448         for (lane = 0; lane < lane_count; lane++) {
 449                 voltage_swing = exynos_dp_get_adjust_request_voltage(
 450                                                 adjust_request, lane);
 451                 pre_emphasis = exynos_dp_get_adjust_request_pre_emphasis(
 452                                                 adjust_request, lane);
 453                 training_lane = DPCD_VOLTAGE_SWING_SET(voltage_swing) |
 454                                 DPCD_PRE_EMPHASIS_SET(pre_emphasis);
 455
 456                 if (voltage_swing == VOLTAGE_LEVEL_3)
 457                         training_lane |= DPCD_MAX_SWING_REACHED;
 458                 if (pre_emphasis == PRE_EMPHASIS_LEVEL_3)
 459                         training_lane |= DPCD_MAX_PRE_EMPHASIS_REACHED;
 460
 461                 dp->link_train.training_lane[lane] = training_lane;
 462         }
 463 }
 464
 465 static int exynos_dp_process_clock_recovery(struct exynos_dp_device *dp)
 466 {
 467         int lane, lane_count, retval;
 468         u8 voltage_swing, pre_emphasis, training_lane;
 469         u8 link_status[2], adjust_request[2];
 470
 471         usleep_range(100, 101);
 472
 473         lane_count = dp->link_train.lane_count;
 474
 475         retval =  exynos_dp_read_bytes_from_dpcd(dp,
 476                         DPCD_ADDR_LANE0_1_STATUS, 2, link_status);
 477         if (retval)
 478                 return retval;
 479
 480         retval =  exynos_dp_read_bytes_from_dpcd(dp,
 481                         DPCD_ADDR_ADJUST_REQUEST_LANE0_1, 2, adjust_request);
 482         if (retval)
 483                 return retval;
 484
 485         if (exynos_dp_clock_recovery_ok(link_status, lane_count) == 0) {
 486                 /* set training pattern 2 for EQ */
 487                 exynos_dp_set_training_pattern(dp, TRAINING_PTN2);
 488
 489                 retval = exynos_dp_write_byte_to_dpcd(dp,
 490                                 DPCD_ADDR_TRAINING_PATTERN_SET,
 491                                 DPCD_SCRAMBLING_DISABLED |
 492                                 DPCD_TRAINING_PATTERN_2);
 493                 if (retval)
 494                         return retval;
 495
 496                 dev_info(dp->dev, "Link Training Clock Recovery success\n");
 497                 dp->link_train.lt_state = EQUALIZER_TRAINING;
 498         } else {
 499                 for (lane = 0; lane < lane_count; lane++) {
 500                         training_lane = exynos_dp_get_lane_link_training(
 501                                                         dp, lane);
 502                         voltage_swing = exynos_dp_get_adjust_request_voltage(
 503                                                         adjust_request, lane);
 504                         pre_emphasis = exynos_dp_get_adjust_request_pre_emphasis(
 505                                                         adjust_request, lane);
 506
 507                         if (DPCD_VOLTAGE_SWING_GET(training_lane) ==
 508                                         voltage_swing &&
 509                             DPCD_PRE_EMPHASIS_GET(training_lane) ==
 510                                         pre_emphasis)
 511                                 dp->link_train.cr_loop[lane]++;
 512
 513                         if (dp->link_train.cr_loop[lane] == MAX_CR_LOOP ||
 514                             voltage_swing == VOLTAGE_LEVEL_3 ||
 515                             pre_emphasis == PRE_EMPHASIS_LEVEL_3) {
 516                                 dev_err(dp->dev, "CR Max reached (%d,%d,%d)\n",
 517                                         dp->link_train.cr_loop[lane],
 518                                         voltage_swing, pre_emphasis);
 519                                 exynos_dp_reduce_link_rate(dp);
 520                                 return -EIO;
 521                         }
 522                 }
 523         }
 524
 525         exynos_dp_get_adjust_training_lane(dp, adjust_request);
 526
 527         for (lane = 0; lane < lane_count; lane++)
 528                 exynos_dp_set_lane_link_training(dp,
 529                         dp->link_train.training_lane[lane], lane);
 530
 531         retval = exynos_dp_write_bytes_to_dpcd(dp,
 532                         DPCD_ADDR_TRAINING_LANE0_SET, lane_count,
 533                         dp->link_train.training_lane);
 534         if (retval)
 535                 return retval;
 536
 537         return retval;
 538 }
 539
 540 static int exynos_dp_process_equalizer_training(struct exynos_dp_device *dp)
 541 {
 542         int lane, lane_count, retval;
 543         u32 reg;
 544         u8 link_align, link_status[2], adjust_request[2];
 545
 546         usleep_range(400, 401);
 547
 548         lane_count = dp->link_train.lane_count;
 549
 550         retval = exynos_dp_read_bytes_from_dpcd(dp,
 551                         DPCD_ADDR_LANE0_1_STATUS, 2, link_status);
 552         if (retval)
 553                 return retval;
 554
 555         if (exynos_dp_clock_recovery_ok(link_status, lane_count)) {
 556                 exynos_dp_reduce_link_rate(dp);
 557                 return -EIO;
 558         }
 559
 560         retval = exynos_dp_read_bytes_from_dpcd(dp,
 561                         DPCD_ADDR_ADJUST_REQUEST_LANE0_1, 2, adjust_request);
 562         if (retval)
 563                 return retval;
 564
 565         retval = exynos_dp_read_byte_from_dpcd(dp,
 566                         DPCD_ADDR_LANE_ALIGN_STATUS_UPDATED, &link_align);
 567         if (retval)
 568                 return retval;
 569
 570         exynos_dp_get_adjust_training_lane(dp, adjust_request);
 571
 572         if (!exynos_dp_channel_eq_ok(link_status, link_align, lane_count)) {
 573                 /* traing pattern Set to Normal */
 574                 exynos_dp_training_pattern_dis(dp);
 575
 576                 dev_info(dp->dev, "Link Training success!\n");
 577
 578                 exynos_dp_get_link_bandwidth(dp, &reg);
 579                 dp->link_train.link_rate = reg;
 580                 dev_dbg(dp->dev, "final bandwidth = %.2x\n",
 581                         dp->link_train.link_rate);
 582
 583                 exynos_dp_get_lane_count(dp, &reg);
 584                 dp->link_train.lane_count = reg;
 585                 dev_dbg(dp->dev, "final lane count = %.2x\n",
 586                         dp->link_train.lane_count);
 587
 588                 /* set enhanced mode if available */
 589                 exynos_dp_set_enhanced_mode(dp);
 590                 dp->link_train.lt_state = FINISHED;
 591
 592                 return 0;
 593         }
 594
 595         /* not all locked */
 596         dp->link_train.eq_loop++;
 597
 598         if (dp->link_train.eq_loop > MAX_EQ_LOOP) {
 599                 dev_err(dp->dev, "EQ Max loop\n");
 600                 exynos_dp_reduce_link_rate(dp);
 601                 return -EIO;
 602         }
 603
 604         for (lane = 0; lane < lane_count; lane++)
 605                 exynos_dp_set_lane_link_training(dp,
 606                         dp->link_train.training_lane[lane], lane);
 607
 608         retval = exynos_dp_write_bytes_to_dpcd(dp, DPCD_ADDR_TRAINING_LANE0_SET,
 609                         lane_count, dp->link_train.training_lane);
 610
 611         return retval;
 612 }
 613
 614 static void exynos_dp_get_max_rx_bandwidth(struct exynos_dp_device *dp,
 615                                         u8 *bandwidth)
 616 {
 617         u8 data;
 618
 619         /*
 620          * For DP rev.1.1, Maximum link rate of Main Link lanes
 621          * 0x06 = 1.62 Gbps, 0x0a = 2.7 Gbps
 622          */
 623         exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_MAX_LINK_RATE, &data);
 624         *bandwidth = data;
 625 }
 626
 627 static void exynos_dp_get_max_rx_lane_count(struct exynos_dp_device *dp,
 628                                         u8 *lane_count)
 629 {
 630         u8 data;
 631
 632         /*
 633          * For DP rev.1.1, Maximum number of Main Link lanes
 634          * 0x01 = 1 lane, 0x02 = 2 lanes, 0x04 = 4 lanes
 635          */
 636         exynos_dp_read_byte_from_dpcd(dp, DPCD_ADDR_MAX_LANE_COUNT, &data);
 637         *lane_count = DPCD_MAX_LANE_COUNT(data);
 638 }
 639
 640 static void exynos_dp_init_training(struct exynos_dp_device *dp,
 641                         enum link_lane_count_type max_lane,
 642                         enum link_rate_type max_rate)
 643 {
 644         /*
 645          * MACRO_RST must be applied after the PLL_LOCK to avoid
 646          * the DP inter pair skew issue for at least 10 us
 647          */
 648         exynos_dp_reset_macro(dp);
 649
 650         /* Initialize by reading RX's DPCD */
 651         exynos_dp_get_max_rx_bandwidth(dp, &dp->link_train.link_rate);
 652         exynos_dp_get_max_rx_lane_count(dp, &dp->link_train.lane_count);
 653
 654         if ((dp->link_train.link_rate != LINK_RATE_1_62GBPS) &&
 655            (dp->link_train.link_rate != LINK_RATE_2_70GBPS)) {
 656                 dev_err(dp->dev, "Rx Max Link Rate is abnormal :%x !\n",
 657                         dp->link_train.link_rate);
 658                 dp->link_train.link_rate = LINK_RATE_1_62GBPS;
 659         }
 660
 661         if (dp->link_train.lane_count == 0) {
 662                 dev_err(dp->dev, "Rx Max Lane count is abnormal :%x !\n",
 663                         dp->link_train.lane_count);
 664                 dp->link_train.lane_count = (u8)LANE_COUNT1;
 665         }
 666
 667         /* Setup TX lane count & rate */
 668         if (dp->link_train.lane_count > max_lane)
 669                 dp->link_train.lane_count = max_lane;
 670         if (dp->link_train.link_rate > max_rate)
 671                 dp->link_train.link_rate = max_rate;
 672
 673         /* All DP analog module power up */
 674         exynos_dp_set_analog_power_down(dp, POWER_ALL, 0);
 675 }
 676
 677 static int exynos_dp_sw_link_training(struct exynos_dp_device *dp)
 678 {
 679         int retval = 0, training_finished = 0;
 680
 681         dp->link_train.lt_state = START;
 682
 683         /* Process here */
 684         while (!retval && !training_finished) {
 685                 switch (dp->link_train.lt_state) {
 686                 case START:
 687                         retval = exynos_dp_link_start(dp);
 688                         if (retval)
 689                                 dev_err(dp->dev, "LT link start failed!\n");
 690                         break;
 691                 case CLOCK_RECOVERY:
 692                         retval = exynos_dp_process_clock_recovery(dp);
 693                         if (retval)
 694                                 dev_err(dp->dev, "LT CR failed!\n");
 695                         break;
 696                 case EQUALIZER_TRAINING:
 697                         retval = exynos_dp_process_equalizer_training(dp);
 698                         if (retval)
 699                                 dev_err(dp->dev, "LT EQ failed!\n");
 700                         break;
 701                 case FINISHED:
 702                         training_finished = 1;
 703                         break;
 704                 case FAILED:
 705                         return -EREMOTEIO;
 706                 }
 707         }
 708         if (retval)
 709                 dev_err(dp->dev, "eDP link training failed (%d)\n", retval);
 710
 711         return retval;
 712 }
 713
 714 static int exynos_dp_set_link_train(struct exynos_dp_device *dp,
 715                                 u32 count,
 716                                 u32 bwtype)
 717 {
 718         int i;
 719         int retval;
 720
 721         for (i = 0; i < DP_TIMEOUT_LOOP_COUNT; i++) {
 722                 exynos_dp_init_training(dp, count, bwtype);
 723                 retval = exynos_dp_sw_link_training(dp);
 724                 if (retval == 0)
 725                         break;
 726
 727                 usleep_range(100, 110);
 728         }
 729
 730         return retval;
 731 }
 732
 733 static int exynos_dp_config_video(struct exynos_dp_device *dp)
 734 {
 735         int retval = 0;
 736         int timeout_loop = 0;
 737         int done_count = 0;
 738
 739         exynos_dp_config_video_slave_mode(dp);
 740
 741         exynos_dp_set_video_color_format(dp);
 742
 743         if (exynos_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
 744                 dev_err(dp->dev, "PLL is not locked yet.\n");
 745                 return -EINVAL;
 746         }
 747
 748         for (;;) {
 749                 timeout_loop++;
 750                 if (exynos_dp_is_slave_video_stream_clock_on(dp) == 0)
 751                         break;
 752                 if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
 753                         dev_err(dp->dev, "Timeout of video streamclk ok\n");
 754                         return -ETIMEDOUT;
 755                 }
 756
 757                 usleep_range(1, 2);
 758         }
 759
 760         /* Set to use the register calculated M/N video */
 761         exynos_dp_set_video_cr_mn(dp, CALCULATED_M, 0, 0);
 762
 763         /* For video bist, Video timing must be generated by register */
 764         exynos_dp_set_video_timing_mode(dp, VIDEO_TIMING_FROM_CAPTURE);
 765
 766         /* Disable video mute */
 767         exynos_dp_enable_video_mute(dp, 0);
 768
 769         /* Configure video slave mode */
 770         exynos_dp_enable_video_master(dp, 0);
 771
 772         /* Enable video */
 773         exynos_dp_start_video(dp);
 774
 775         timeout_loop = 0;
 776
 777         for (;;) {
 778                 timeout_loop++;
 779                 if (exynos_dp_is_video_stream_on(dp) == 0) {
 780                         done_count++;
 781                         if (done_count > 10)
 782                                 break;
 783                 } else if (done_count) {
 784                         done_count = 0;
 785                 }
 786                 if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
 787                         dev_err(dp->dev, "Timeout of video streamclk ok\n");
 788                         return -ETIMEDOUT;
 789                 }
 790
 791                 usleep_range(1000, 1001);
 792         }
 793
 794         if (retval != 0)
 795                 dev_err(dp->dev, "Video stream is not detected!\n");
 796
 797         return retval;
 798 }
 799
 800 static void exynos_dp_enable_scramble(struct exynos_dp_device *dp, bool enable)
 801 {
 802         u8 data;
 803
 804         if (enable) {
 805                 exynos_dp_enable_scrambling(dp);
 806
 807                 exynos_dp_read_byte_from_dpcd(dp,
 808                         DPCD_ADDR_TRAINING_PATTERN_SET,
 809                         &data);
 810                 exynos_dp_write_byte_to_dpcd(dp,
 811                         DPCD_ADDR_TRAINING_PATTERN_SET,
 812                         (u8)(data & ~DPCD_SCRAMBLING_DISABLED));
 813         } else {
 814                 exynos_dp_disable_scrambling(dp);
 815
 816                 exynos_dp_read_byte_from_dpcd(dp,
 817                         DPCD_ADDR_TRAINING_PATTERN_SET,
 818                         &data);
 819                 exynos_dp_write_byte_to_dpcd(dp,
 820                         DPCD_ADDR_TRAINING_PATTERN_SET,
 821                         (u8)(data | DPCD_SCRAMBLING_DISABLED));
 822         }
 823 }
 824
 825 static irqreturn_t exynos_dp_irq_handler(int irq, void *arg)
 826 {
 827         struct exynos_dp_device *dp = arg;
 828
 829         enum dp_irq_type irq_type;
 830
 831         irq_type = exynos_dp_get_irq_type(dp);
 832         switch (irq_type) {
 833         case DP_IRQ_TYPE_HP_CABLE_IN:
 834                 dev_dbg(dp->dev, "Received irq - cable in\n");
 835                 schedule_work(&dp->hotplug_work);
 836                 exynos_dp_clear_hotplug_interrupts(dp);
 837                 break;
 838         case DP_IRQ_TYPE_HP_CABLE_OUT:
 839                 dev_dbg(dp->dev, "Received irq - cable out\n");
 840                 exynos_dp_clear_hotplug_interrupts(dp);
 841                 break;
 842         case DP_IRQ_TYPE_HP_CHANGE:
 843                 /*
 844                  * We get these change notifications once in a while, but there
 845                  * is nothing we can do with them. Just ignore it for now and
 846                  * only handle cable changes.
 847                  */
 848                 dev_dbg(dp->dev, "Received irq - hotplug change; ignoring.\n");
 849                 exynos_dp_clear_hotplug_interrupts(dp);
 850                 break;
 851         default:
 852                 dev_err(dp->dev, "Received irq - unknown type!\n");
 853                 break;
 854         }
 855         return IRQ_HANDLED;
 856 }
 857
 858 static void exynos_dp_hotplug(struct work_struct *work)
 859 {
 860         struct exynos_dp_device *dp;
 861         int ret;
 862
 863         dp = container_of(work, struct exynos_dp_device, hotplug_work);
 864
 865         ret = exynos_dp_detect_hpd(dp);
 866         if (ret) {
 867                 /* Cable has been disconnected, we're done */
 868                 return;
 869         }
 870
 871         ret = exynos_dp_handle_edid(dp);
 872         if (ret) {
 873                 dev_err(dp->dev, "unable to handle edid\n");
 874                 return;
 875         }
 876
 877         ret = exynos_dp_set_link_train(dp, dp->video_info->lane_count,
 878                                         dp->video_info->link_rate);
 879         if (ret) {
 880                 dev_err(dp->dev, "unable to do link train\n");
 881                 return;
 882         }
 883
 884         exynos_dp_enable_scramble(dp, 1);
 885         exynos_dp_enable_rx_to_enhanced_mode(dp, 1);
 886         exynos_dp_enable_enhanced_mode(dp, 1);
 887
 888         exynos_dp_set_lane_count(dp, dp->video_info->lane_count);
 889         exynos_dp_set_link_bandwidth(dp, dp->video_info->link_rate);
 890
 891         exynos_dp_init_video(dp);
 892         ret = exynos_dp_config_video(dp);
 893         if (ret)
 894                 dev_err(dp->dev, "unable to config video\n");
 895 }
 896
 897 #ifdef CONFIG_OF
 898 static struct exynos_dp_platdata *exynos_dp_dt_parse_pdata(struct device *dev)
 899 {
 900         struct device_node *dp_node = dev->of_node;
 901         struct exynos_dp_platdata *pd;
 902         struct video_info *dp_video_config;
 903
 904         pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
 905         if (!pd) {
 906                 dev_err(dev, "memory allocation for pdata failed\n");
 907                 return ERR_PTR(-ENOMEM);
 908         }
 909         dp_video_config = devm_kzalloc(dev,
 910                                 sizeof(*dp_video_config), GFP_KERNEL);
 911
 912         if (!dp_video_config) {
 913                 dev_err(dev, "memory allocation for video config failed\n");
 914                 return ERR_PTR(-ENOMEM);
 915         }
 916         pd->video_info = dp_video_config;
 917
 918         dp_video_config->h_sync_polarity =
 919                 of_property_read_bool(dp_node, "hsync-active-high");
 920
 921         dp_video_config->v_sync_polarity =
 922                 of_property_read_bool(dp_node, "vsync-active-high");
 923
 924         dp_video_config->interlaced =
 925                 of_property_read_bool(dp_node, "interlaced");
 926
 927         if (of_property_read_u32(dp_node, "samsung,color-space",
 928                                 &dp_video_config->color_space)) {
 929                 dev_err(dev, "failed to get color-space\n");
 930                 return ERR_PTR(-EINVAL);
 931         }
 932
 933         if (of_property_read_u32(dp_node, "samsung,dynamic-range",
 934                                 &dp_video_config->dynamic_range)) {
 935                 dev_err(dev, "failed to get dynamic-range\n");
 936                 return ERR_PTR(-EINVAL);
 937         }
 938
 939         if (of_property_read_u32(dp_node, "samsung,ycbcr-coeff",
 940                                 &dp_video_config->ycbcr_coeff)) {
 941                 dev_err(dev, "failed to get ycbcr-coeff\n");
 942                 return ERR_PTR(-EINVAL);
 943         }
 944
 945         if (of_property_read_u32(dp_node, "samsung,color-depth",
 946                                 &dp_video_config->color_depth)) {
 947                 dev_err(dev, "failed to get color-depth\n");
 948                 return ERR_PTR(-EINVAL);
 949         }
 950
 951         if (of_property_read_u32(dp_node, "samsung,link-rate",
 952                                 &dp_video_config->link_rate)) {
 953                 dev_err(dev, "failed to get link-rate\n");
 954                 return ERR_PTR(-EINVAL);
 955         }
 956
 957         if (of_property_read_u32(dp_node, "samsung,lane-count",
 958                                 &dp_video_config->lane_count)) {
 959                 dev_err(dev, "failed to get lane-count\n");
 960                 return ERR_PTR(-EINVAL);
 961         }
 962
 963         return pd;
 964 }
 965
 966 static int exynos_dp_dt_parse_phydata(struct exynos_dp_device *dp)
 967 {
 968         struct device_node *dp_phy_node = of_node_get(dp->dev->of_node);
 969         u32 phy_base;
 970         int ret = 0;
 971
 972         dp_phy_node = of_find_node_by_name(dp_phy_node, "dptx-phy");
 973         if (!dp_phy_node) {
 974                 dev_err(dp->dev, "could not find dptx-phy node\n");
 975                 return -ENODEV;
 976         }
 977
 978         if (of_property_read_u32(dp_phy_node, "reg", &phy_base)) {
 979                 dev_err(dp->dev, "failed to get reg for dptx-phy\n");
 980                 ret = -EINVAL;
 981                 goto err;
 982         }
 983
 984         if (of_property_read_u32(dp_phy_node, "samsung,enable-mask",
 985                                 &dp->enable_mask)) {
 986                 dev_err(dp->dev, "failed to get enable-mask for dptx-phy\n");
 987                 ret = -EINVAL;
 988                 goto err;
 989         }
 990
 991         dp->phy_addr = ioremap(phy_base, SZ_4);
 992         if (!dp->phy_addr) {
 993                 dev_err(dp->dev, "failed to ioremap dp-phy\n");
 994                 ret = -ENOMEM;
 995                 goto err;
 996         }
 997
 998 err:
 999         of_node_put(dp_phy_node);
1000
1001         return ret;
1002 }
1003
1004 static void exynos_dp_phy_init(struct exynos_dp_device *dp)
1005 {
1006         u32 reg;
1007
1008         reg = __raw_readl(dp->phy_addr);
1009         reg |= dp->enable_mask;
1010         __raw_writel(reg, dp->phy_addr);
1011 }
1012
1013 static void exynos_dp_phy_exit(struct exynos_dp_device *dp)
1014 {
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 #else
1022 static struct exynos_dp_platdata *exynos_dp_dt_parse_pdata(struct device *dev)
1023 {
1024         return NULL;
1025 }
1026
1027 static int exynos_dp_dt_parse_phydata(struct exynos_dp_device *dp)
1028 {
1029         return -EINVAL;
1030 }
1031
1032 static void exynos_dp_phy_init(struct exynos_dp_device *dp)
1033 {
1034         return;
1035 }
1036
1037 static void exynos_dp_phy_exit(struct exynos_dp_device *dp)
1038 {
1039         return;
1040 }
1041 #endif /* CONFIG_OF */
1042
1043 static int exynos_dp_probe(struct platform_device *pdev)
1044 {
1045         struct resource *res;
1046         struct exynos_dp_device *dp;
1047         struct exynos_dp_platdata *pdata;
1048
1049         int ret = 0;
1050
1051         dp = devm_kzalloc(&pdev->dev, sizeof(struct exynos_dp_device),
1052                                 GFP_KERNEL);
1053         if (!dp) {
1054                 dev_err(&pdev->dev, "no memory for device data\n");
1055                 return -ENOMEM;
1056         }
1057
1058         dp->dev = &pdev->dev;
1059
1060         if (pdev->dev.of_node) {
1061                 pdata = exynos_dp_dt_parse_pdata(&pdev->dev);
1062                 if (IS_ERR(pdata))
1063                         return PTR_ERR(pdata);
1064
1065                 ret = exynos_dp_dt_parse_phydata(dp);
1066                 if (ret)
1067                         return ret;
1068         } else {
1069                 pdata = pdev->dev.platform_data;
1070                 if (!pdata) {
1071                         dev_err(&pdev->dev, "no platform data\n");
1072                         return -EINVAL;
1073                 }
1074         }
1075
1076         dp->clock = devm_clk_get(&pdev->dev, "dp");
1077         if (IS_ERR(dp->clock)) {
1078                 dev_err(&pdev->dev, "failed to get clock\n");
1079                 return PTR_ERR(dp->clock);
1080         }
1081
1082         clk_prepare_enable(dp->clock);
1083
1084         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1085
1086         dp->reg_base = devm_ioremap_resource(&pdev->dev, res);
1087         if (IS_ERR(dp->reg_base))
1088                 return PTR_ERR(dp->reg_base);
1089
1090         dp->irq = platform_get_irq(pdev, 0);
1091         if (dp->irq == -ENXIO) {
1092                 dev_err(&pdev->dev, "failed to get irq\n");
1093                 return -ENODEV;
1094         }
1095
1096         INIT_WORK(&dp->hotplug_work, exynos_dp_hotplug);
1097
1098         dp->video_info = pdata->video_info;
1099
1100         if (pdev->dev.of_node) {
1101                 if (dp->phy_addr)
1102                         exynos_dp_phy_init(dp);
1103         } else {
1104                 if (pdata->phy_init)
1105                         pdata->phy_init();
1106         }
1107
1108         exynos_dp_init_dp(dp);
1109
1110         ret = devm_request_irq(&pdev->dev, dp->irq, exynos_dp_irq_handler, 0,
1111                                 "exynos-dp", dp);
1112         if (ret) {
1113                 dev_err(&pdev->dev, "failed to request irq\n");
1114                 return ret;
1115         }
1116
1117         platform_set_drvdata(pdev, dp);
1118
1119         return 0;
1120 }
1121
1122 static int exynos_dp_remove(struct platform_device *pdev)
1123 {
1124         struct exynos_dp_platdata *pdata = pdev->dev.platform_data;
1125         struct exynos_dp_device *dp = platform_get_drvdata(pdev);
1126
1127         flush_work(&dp->hotplug_work);
1128
1129         if (pdev->dev.of_node) {
1130                 if (dp->phy_addr)
1131                         exynos_dp_phy_exit(dp);
1132         } else {
1133                 if (pdata->phy_exit)
1134                         pdata->phy_exit();
1135         }
1136
1137         clk_disable_unprepare(dp->clock);
1138
1139
1140         return 0;
1141 }
1142
1143 #ifdef CONFIG_PM_SLEEP
1144 static int exynos_dp_suspend(struct device *dev)
1145 {
1146         struct exynos_dp_platdata *pdata = dev->platform_data;
1147         struct exynos_dp_device *dp = dev_get_drvdata(dev);
1148
1149         disable_irq(dp->irq);
1150
1151         flush_work(&dp->hotplug_work);
1152
1153         if (dev->of_node) {
1154                 if (dp->phy_addr)
1155                         exynos_dp_phy_exit(dp);
1156         } else {
1157                 if (pdata->phy_exit)
1158                         pdata->phy_exit();
1159         }
1160
1161         clk_disable_unprepare(dp->clock);
1162
1163         return 0;
1164 }
1165
1166 static int exynos_dp_resume(struct device *dev)
1167 {
1168         struct exynos_dp_platdata *pdata = dev->platform_data;
1169         struct exynos_dp_device *dp = dev_get_drvdata(dev);
1170
1171         if (dev->of_node) {
1172                 if (dp->phy_addr)
1173                         exynos_dp_phy_init(dp);
1174         } else {
1175                 if (pdata->phy_init)
1176                         pdata->phy_init();
1177         }
1178
1179         clk_prepare_enable(dp->clock);
1180
1181         exynos_dp_init_dp(dp);
1182
1183         enable_irq(dp->irq);
1184
1185         return 0;
1186 }
1187 #endif
1188
1189 static const struct dev_pm_ops exynos_dp_pm_ops = {
1190         SET_SYSTEM_SLEEP_PM_OPS(exynos_dp_suspend, exynos_dp_resume)
1191 };
1192
1193 static const struct of_device_id exynos_dp_match[] = {
1194         { .compatible = "samsung,exynos5-dp" },
1195         {},
1196 };
1197 MODULE_DEVICE_TABLE(of, exynos_dp_match);
1198
1199 static struct platform_driver exynos_dp_driver = {
1200         .probe          = exynos_dp_probe,
1201         .remove         = exynos_dp_remove,
1202         .driver         = {
1203                 .name   = "exynos-dp",
1204                 .owner  = THIS_MODULE,
1205                 .pm     = &exynos_dp_pm_ops,
1206                 .of_match_table = of_match_ptr(exynos_dp_match),
1207         },
1208 };
1209
1210 module_platform_driver(exynos_dp_driver);
1211
1212 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
1213 MODULE_DESCRIPTION("Samsung SoC DP Driver");
1214 MODULE_LICENSE("GPL");