linux/drivers/gpu/drm/exynos/exynos_dp_core.c
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   1/*
   2 * Samsung SoC DP (Display Port) interface driver.
   3 *
   4 * Copyright (C) 2012 Samsung Electronics Co., Ltd.
   5 * Author: Jingoo Han <jg1.han@samsung.com>
   6 *
   7 * This program is free software; you can redistribute it and/or modify it
   8 * under the terms of the GNU General Public License as published by the
   9 * Free Software Foundation; either version 2 of the License, or (at your
  10 * option) any later version.
  11 */
  12
  13#include <linux/module.h>
  14#include <linux/platform_device.h>
  15#include <linux/err.h>
  16#include <linux/clk.h>
  17#include <linux/io.h>
  18#include <linux/interrupt.h>
  19#include <linux/of.h>
  20#include <linux/of_gpio.h>
  21#include <linux/of_graph.h>
  22#include <linux/gpio.h>
  23#include <linux/component.h>
  24#include <linux/phy/phy.h>
  25#include <video/of_display_timing.h>
  26#include <video/of_videomode.h>
  27
  28#include <drm/drmP.h>
  29#include <drm/drm_crtc.h>
  30#include <drm/drm_crtc_helper.h>
  31#include <drm/drm_atomic_helper.h>
  32#include <drm/drm_panel.h>
  33
  34#include "exynos_dp_core.h"
  35#include "exynos_drm_crtc.h"
  36
  37#define ctx_from_connector(c)   container_of(c, struct exynos_dp_device, \
  38                                        connector)
  39
  40static inline struct exynos_drm_crtc *dp_to_crtc(struct exynos_dp_device *dp)
  41{
  42        return to_exynos_crtc(dp->encoder.crtc);
  43}
  44
  45static inline struct exynos_dp_device *encoder_to_dp(
  46                                                struct drm_encoder *e)
  47{
  48        return container_of(e, struct exynos_dp_device, encoder);
  49}
  50
  51struct bridge_init {
  52        struct i2c_client *client;
  53        struct device_node *node;
  54};
  55
  56static void exynos_dp_init_dp(struct exynos_dp_device *dp)
  57{
  58        exynos_dp_reset(dp);
  59
  60        exynos_dp_swreset(dp);
  61
  62        exynos_dp_init_analog_param(dp);
  63        exynos_dp_init_interrupt(dp);
  64
  65        /* SW defined function Normal operation */
  66        exynos_dp_enable_sw_function(dp);
  67
  68        exynos_dp_config_interrupt(dp);
  69        exynos_dp_init_analog_func(dp);
  70
  71        exynos_dp_init_hpd(dp);
  72        exynos_dp_init_aux(dp);
  73}
  74
  75static int exynos_dp_detect_hpd(struct exynos_dp_device *dp)
  76{
  77        int timeout_loop = 0;
  78
  79        while (exynos_dp_get_plug_in_status(dp) != 0) {
  80                timeout_loop++;
  81                if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
  82                        dev_err(dp->dev, "failed to get hpd plug status\n");
  83                        return -ETIMEDOUT;
  84                }
  85                usleep_range(10, 11);
  86        }
  87
  88        return 0;
  89}
  90
  91static unsigned char exynos_dp_calc_edid_check_sum(unsigned char *edid_data)
  92{
  93        int i;
  94        unsigned char sum = 0;
  95
  96        for (i = 0; i < EDID_BLOCK_LENGTH; i++)
  97                sum = sum + edid_data[i];
  98
  99        return sum;
 100}
 101
 102static int exynos_dp_read_edid(struct exynos_dp_device *dp)
 103{
 104        unsigned char edid[EDID_BLOCK_LENGTH * 2];
 105        unsigned int extend_block = 0;
 106        unsigned char sum;
 107        unsigned char test_vector;
 108        int retval;
 109
 110        /*
 111         * EDID device address is 0x50.
 112         * However, if necessary, you must have set upper address
 113         * into E-EDID in I2C device, 0x30.
 114         */
 115
 116        /* Read Extension Flag, Number of 128-byte EDID extension blocks */
 117        retval = exynos_dp_read_byte_from_i2c(dp, I2C_EDID_DEVICE_ADDR,
 118                                EDID_EXTENSION_FLAG,
 119                                &extend_block);
 120        if (retval)
 121                return retval;
 122
 123        if (extend_block > 0) {
 124                dev_dbg(dp->dev, "EDID data includes a single extension!\n");
 125
 126                /* Read EDID data */
 127                retval = exynos_dp_read_bytes_from_i2c(dp, I2C_EDID_DEVICE_ADDR,
 128                                                EDID_HEADER_PATTERN,
 129                                                EDID_BLOCK_LENGTH,
 130                                                &edid[EDID_HEADER_PATTERN]);
 131                if (retval != 0) {
 132                        dev_err(dp->dev, "EDID Read failed!\n");
 133                        return -EIO;
 134                }
 135                sum = exynos_dp_calc_edid_check_sum(edid);
 136                if (sum != 0) {
 137                        dev_err(dp->dev, "EDID bad checksum!\n");
 138                        return -EIO;
 139                }
 140
 141                /* Read additional EDID data */
 142                retval = exynos_dp_read_bytes_from_i2c(dp,
 143                                I2C_EDID_DEVICE_ADDR,
 144                                EDID_BLOCK_LENGTH,
 145                                EDID_BLOCK_LENGTH,
 146                                &edid[EDID_BLOCK_LENGTH]);
 147                if (retval != 0) {
 148                        dev_err(dp->dev, "EDID Read failed!\n");
 149                        return -EIO;
 150                }
 151                sum = exynos_dp_calc_edid_check_sum(&edid[EDID_BLOCK_LENGTH]);
 152                if (sum != 0) {
 153                        dev_err(dp->dev, "EDID bad checksum!\n");
 154                        return -EIO;
 155                }
 156
 157                exynos_dp_read_byte_from_dpcd(dp, DP_TEST_REQUEST,
 158                                        &test_vector);
 159                if (test_vector & DP_TEST_LINK_EDID_READ) {
 160                        exynos_dp_write_byte_to_dpcd(dp,
 161                                DP_TEST_EDID_CHECKSUM,
 162                                edid[EDID_BLOCK_LENGTH + EDID_CHECKSUM]);
 163                        exynos_dp_write_byte_to_dpcd(dp,
 164                                DP_TEST_RESPONSE,
 165                                DP_TEST_EDID_CHECKSUM_WRITE);
 166                }
 167        } else {
 168                dev_info(dp->dev, "EDID data does not include any extensions.\n");
 169
 170                /* Read EDID data */
 171                retval = exynos_dp_read_bytes_from_i2c(dp,
 172                                I2C_EDID_DEVICE_ADDR,
 173                                EDID_HEADER_PATTERN,
 174                                EDID_BLOCK_LENGTH,
 175                                &edid[EDID_HEADER_PATTERN]);
 176                if (retval != 0) {
 177                        dev_err(dp->dev, "EDID Read failed!\n");
 178                        return -EIO;
 179                }
 180                sum = exynos_dp_calc_edid_check_sum(edid);
 181                if (sum != 0) {
 182                        dev_err(dp->dev, "EDID bad checksum!\n");
 183                        return -EIO;
 184                }
 185
 186                exynos_dp_read_byte_from_dpcd(dp,
 187                        DP_TEST_REQUEST,
 188                        &test_vector);
 189                if (test_vector & DP_TEST_LINK_EDID_READ) {
 190                        exynos_dp_write_byte_to_dpcd(dp,
 191                                DP_TEST_EDID_CHECKSUM,
 192                                edid[EDID_CHECKSUM]);
 193                        exynos_dp_write_byte_to_dpcd(dp,
 194                                DP_TEST_RESPONSE,
 195                                DP_TEST_EDID_CHECKSUM_WRITE);
 196                }
 197        }
 198
 199        dev_dbg(dp->dev, "EDID Read success!\n");
 200        return 0;
 201}
 202
 203static int exynos_dp_handle_edid(struct exynos_dp_device *dp)
 204{
 205        u8 buf[12];
 206        int i;
 207        int retval;
 208
 209        /* Read DPCD DP_DPCD_REV~RECEIVE_PORT1_CAP_1 */
 210        retval = exynos_dp_read_bytes_from_dpcd(dp, DP_DPCD_REV,
 211                                12, buf);
 212        if (retval)
 213                return retval;
 214
 215        /* Read EDID */
 216        for (i = 0; i < 3; i++) {
 217                retval = exynos_dp_read_edid(dp);
 218                if (!retval)
 219                        break;
 220        }
 221
 222        return retval;
 223}
 224
 225static void exynos_dp_enable_rx_to_enhanced_mode(struct exynos_dp_device *dp,
 226                                                bool enable)
 227{
 228        u8 data;
 229
 230        exynos_dp_read_byte_from_dpcd(dp, DP_LANE_COUNT_SET, &data);
 231
 232        if (enable)
 233                exynos_dp_write_byte_to_dpcd(dp, DP_LANE_COUNT_SET,
 234                        DP_LANE_COUNT_ENHANCED_FRAME_EN |
 235                        DPCD_LANE_COUNT_SET(data));
 236        else
 237                exynos_dp_write_byte_to_dpcd(dp, DP_LANE_COUNT_SET,
 238                        DPCD_LANE_COUNT_SET(data));
 239}
 240
 241static int exynos_dp_is_enhanced_mode_available(struct exynos_dp_device *dp)
 242{
 243        u8 data;
 244        int retval;
 245
 246        exynos_dp_read_byte_from_dpcd(dp, DP_MAX_LANE_COUNT, &data);
 247        retval = DPCD_ENHANCED_FRAME_CAP(data);
 248
 249        return retval;
 250}
 251
 252static void exynos_dp_set_enhanced_mode(struct exynos_dp_device *dp)
 253{
 254        u8 data;
 255
 256        data = exynos_dp_is_enhanced_mode_available(dp);
 257        exynos_dp_enable_rx_to_enhanced_mode(dp, data);
 258        exynos_dp_enable_enhanced_mode(dp, data);
 259}
 260
 261static void exynos_dp_training_pattern_dis(struct exynos_dp_device *dp)
 262{
 263        exynos_dp_set_training_pattern(dp, DP_NONE);
 264
 265        exynos_dp_write_byte_to_dpcd(dp,
 266                DP_TRAINING_PATTERN_SET,
 267                DP_TRAINING_PATTERN_DISABLE);
 268}
 269
 270static void exynos_dp_set_lane_lane_pre_emphasis(struct exynos_dp_device *dp,
 271                                        int pre_emphasis, int lane)
 272{
 273        switch (lane) {
 274        case 0:
 275                exynos_dp_set_lane0_pre_emphasis(dp, pre_emphasis);
 276                break;
 277        case 1:
 278                exynos_dp_set_lane1_pre_emphasis(dp, pre_emphasis);
 279                break;
 280
 281        case 2:
 282                exynos_dp_set_lane2_pre_emphasis(dp, pre_emphasis);
 283                break;
 284
 285        case 3:
 286                exynos_dp_set_lane3_pre_emphasis(dp, pre_emphasis);
 287                break;
 288        }
 289}
 290
 291static int exynos_dp_link_start(struct exynos_dp_device *dp)
 292{
 293        u8 buf[4];
 294        int lane, lane_count, pll_tries, retval;
 295
 296        lane_count = dp->link_train.lane_count;
 297
 298        dp->link_train.lt_state = CLOCK_RECOVERY;
 299        dp->link_train.eq_loop = 0;
 300
 301        for (lane = 0; lane < lane_count; lane++)
 302                dp->link_train.cr_loop[lane] = 0;
 303
 304        /* Set link rate and count as you want to establish*/
 305        exynos_dp_set_link_bandwidth(dp, dp->link_train.link_rate);
 306        exynos_dp_set_lane_count(dp, dp->link_train.lane_count);
 307
 308        /* Setup RX configuration */
 309        buf[0] = dp->link_train.link_rate;
 310        buf[1] = dp->link_train.lane_count;
 311        retval = exynos_dp_write_bytes_to_dpcd(dp, DP_LINK_BW_SET,
 312                                2, buf);
 313        if (retval)
 314                return retval;
 315
 316        /* Set TX pre-emphasis to minimum */
 317        for (lane = 0; lane < lane_count; lane++)
 318                exynos_dp_set_lane_lane_pre_emphasis(dp,
 319                        PRE_EMPHASIS_LEVEL_0, lane);
 320
 321        /* Wait for PLL lock */
 322        pll_tries = 0;
 323        while (exynos_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
 324                if (pll_tries == DP_TIMEOUT_LOOP_COUNT) {
 325                        dev_err(dp->dev, "Wait for PLL lock timed out\n");
 326                        return -ETIMEDOUT;
 327                }
 328
 329                pll_tries++;
 330                usleep_range(90, 120);
 331        }
 332
 333        /* Set training pattern 1 */
 334        exynos_dp_set_training_pattern(dp, TRAINING_PTN1);
 335
 336        /* Set RX training pattern */
 337        retval = exynos_dp_write_byte_to_dpcd(dp,
 338                        DP_TRAINING_PATTERN_SET,
 339                        DP_LINK_SCRAMBLING_DISABLE | DP_TRAINING_PATTERN_1);
 340        if (retval)
 341                return retval;
 342
 343        for (lane = 0; lane < lane_count; lane++)
 344                buf[lane] = DP_TRAIN_PRE_EMPH_LEVEL_0 |
 345                            DP_TRAIN_VOLTAGE_SWING_LEVEL_0;
 346
 347        retval = exynos_dp_write_bytes_to_dpcd(dp, DP_TRAINING_LANE0_SET,
 348                        lane_count, buf);
 349
 350        return retval;
 351}
 352
 353static unsigned char exynos_dp_get_lane_status(u8 link_status[2], int lane)
 354{
 355        int shift = (lane & 1) * 4;
 356        u8 link_value = link_status[lane>>1];
 357
 358        return (link_value >> shift) & 0xf;
 359}
 360
 361static int exynos_dp_clock_recovery_ok(u8 link_status[2], int lane_count)
 362{
 363        int lane;
 364        u8 lane_status;
 365
 366        for (lane = 0; lane < lane_count; lane++) {
 367                lane_status = exynos_dp_get_lane_status(link_status, lane);
 368                if ((lane_status & DP_LANE_CR_DONE) == 0)
 369                        return -EINVAL;
 370        }
 371        return 0;
 372}
 373
 374static int exynos_dp_channel_eq_ok(u8 link_status[2], u8 link_align,
 375                                int lane_count)
 376{
 377        int lane;
 378        u8 lane_status;
 379
 380        if ((link_align & DP_INTERLANE_ALIGN_DONE) == 0)
 381                return -EINVAL;
 382
 383        for (lane = 0; lane < lane_count; lane++) {
 384                lane_status = exynos_dp_get_lane_status(link_status, lane);
 385                lane_status &= DP_CHANNEL_EQ_BITS;
 386                if (lane_status != DP_CHANNEL_EQ_BITS)
 387                        return -EINVAL;
 388        }
 389
 390        return 0;
 391}
 392
 393static unsigned char exynos_dp_get_adjust_request_voltage(u8 adjust_request[2],
 394                                                        int lane)
 395{
 396        int shift = (lane & 1) * 4;
 397        u8 link_value = adjust_request[lane>>1];
 398
 399        return (link_value >> shift) & 0x3;
 400}
 401
 402static unsigned char exynos_dp_get_adjust_request_pre_emphasis(
 403                                        u8 adjust_request[2],
 404                                        int lane)
 405{
 406        int shift = (lane & 1) * 4;
 407        u8 link_value = adjust_request[lane>>1];
 408
 409        return ((link_value >> shift) & 0xc) >> 2;
 410}
 411
 412static void exynos_dp_set_lane_link_training(struct exynos_dp_device *dp,
 413                                        u8 training_lane_set, int lane)
 414{
 415        switch (lane) {
 416        case 0:
 417                exynos_dp_set_lane0_link_training(dp, training_lane_set);
 418                break;
 419        case 1:
 420                exynos_dp_set_lane1_link_training(dp, training_lane_set);
 421                break;
 422
 423        case 2:
 424                exynos_dp_set_lane2_link_training(dp, training_lane_set);
 425                break;
 426
 427        case 3:
 428                exynos_dp_set_lane3_link_training(dp, training_lane_set);
 429                break;
 430        }
 431}
 432
 433static unsigned int exynos_dp_get_lane_link_training(
 434                                struct exynos_dp_device *dp,
 435                                int lane)
 436{
 437        u32 reg;
 438
 439        switch (lane) {
 440        case 0:
 441                reg = exynos_dp_get_lane0_link_training(dp);
 442                break;
 443        case 1:
 444                reg = exynos_dp_get_lane1_link_training(dp);
 445                break;
 446        case 2:
 447                reg = exynos_dp_get_lane2_link_training(dp);
 448                break;
 449        case 3:
 450                reg = exynos_dp_get_lane3_link_training(dp);
 451                break;
 452        default:
 453                WARN_ON(1);
 454                return 0;
 455        }
 456
 457        return reg;
 458}
 459
 460static void exynos_dp_reduce_link_rate(struct exynos_dp_device *dp)
 461{
 462        exynos_dp_training_pattern_dis(dp);
 463        exynos_dp_set_enhanced_mode(dp);
 464
 465        dp->link_train.lt_state = FAILED;
 466}
 467
 468static void exynos_dp_get_adjust_training_lane(struct exynos_dp_device *dp,
 469                                        u8 adjust_request[2])
 470{
 471        int lane, lane_count;
 472        u8 voltage_swing, pre_emphasis, training_lane;
 473
 474        lane_count = dp->link_train.lane_count;
 475        for (lane = 0; lane < lane_count; lane++) {
 476                voltage_swing = exynos_dp_get_adjust_request_voltage(
 477                                                adjust_request, lane);
 478                pre_emphasis = exynos_dp_get_adjust_request_pre_emphasis(
 479                                                adjust_request, lane);
 480                training_lane = DPCD_VOLTAGE_SWING_SET(voltage_swing) |
 481                                DPCD_PRE_EMPHASIS_SET(pre_emphasis);
 482
 483                if (voltage_swing == VOLTAGE_LEVEL_3)
 484                        training_lane |= DP_TRAIN_MAX_SWING_REACHED;
 485                if (pre_emphasis == PRE_EMPHASIS_LEVEL_3)
 486                        training_lane |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
 487
 488                dp->link_train.training_lane[lane] = training_lane;
 489        }
 490}
 491
 492static int exynos_dp_process_clock_recovery(struct exynos_dp_device *dp)
 493{
 494        int lane, lane_count, retval;
 495        u8 voltage_swing, pre_emphasis, training_lane;
 496        u8 link_status[2], adjust_request[2];
 497
 498        usleep_range(100, 101);
 499
 500        lane_count = dp->link_train.lane_count;
 501
 502        retval =  exynos_dp_read_bytes_from_dpcd(dp,
 503                        DP_LANE0_1_STATUS, 2, link_status);
 504        if (retval)
 505                return retval;
 506
 507        retval =  exynos_dp_read_bytes_from_dpcd(dp,
 508                        DP_ADJUST_REQUEST_LANE0_1, 2, adjust_request);
 509        if (retval)
 510                return retval;
 511
 512        if (exynos_dp_clock_recovery_ok(link_status, lane_count) == 0) {
 513                /* set training pattern 2 for EQ */
 514                exynos_dp_set_training_pattern(dp, TRAINING_PTN2);
 515
 516                retval = exynos_dp_write_byte_to_dpcd(dp,
 517                                DP_TRAINING_PATTERN_SET,
 518                                DP_LINK_SCRAMBLING_DISABLE |
 519                                DP_TRAINING_PATTERN_2);
 520                if (retval)
 521                        return retval;
 522
 523                dev_info(dp->dev, "Link Training Clock Recovery success\n");
 524                dp->link_train.lt_state = EQUALIZER_TRAINING;
 525        } else {
 526                for (lane = 0; lane < lane_count; lane++) {
 527                        training_lane = exynos_dp_get_lane_link_training(
 528                                                        dp, lane);
 529                        voltage_swing = exynos_dp_get_adjust_request_voltage(
 530                                                        adjust_request, lane);
 531                        pre_emphasis = exynos_dp_get_adjust_request_pre_emphasis(
 532                                                        adjust_request, lane);
 533
 534                        if (DPCD_VOLTAGE_SWING_GET(training_lane) ==
 535                                        voltage_swing &&
 536                            DPCD_PRE_EMPHASIS_GET(training_lane) ==
 537                                        pre_emphasis)
 538                                dp->link_train.cr_loop[lane]++;
 539
 540                        if (dp->link_train.cr_loop[lane] == MAX_CR_LOOP ||
 541                            voltage_swing == VOLTAGE_LEVEL_3 ||
 542                            pre_emphasis == PRE_EMPHASIS_LEVEL_3) {
 543                                dev_err(dp->dev, "CR Max reached (%d,%d,%d)\n",
 544                                        dp->link_train.cr_loop[lane],
 545                                        voltage_swing, pre_emphasis);
 546                                exynos_dp_reduce_link_rate(dp);
 547                                return -EIO;
 548                        }
 549                }
 550        }
 551
 552        exynos_dp_get_adjust_training_lane(dp, adjust_request);
 553
 554        for (lane = 0; lane < lane_count; lane++)
 555                exynos_dp_set_lane_link_training(dp,
 556                        dp->link_train.training_lane[lane], lane);
 557
 558        retval = exynos_dp_write_bytes_to_dpcd(dp,
 559                        DP_TRAINING_LANE0_SET, lane_count,
 560                        dp->link_train.training_lane);
 561        if (retval)
 562                return retval;
 563
 564        return retval;
 565}
 566
 567static int exynos_dp_process_equalizer_training(struct exynos_dp_device *dp)
 568{
 569        int lane, lane_count, retval;
 570        u32 reg;
 571        u8 link_align, link_status[2], adjust_request[2];
 572
 573        usleep_range(400, 401);
 574
 575        lane_count = dp->link_train.lane_count;
 576
 577        retval = exynos_dp_read_bytes_from_dpcd(dp,
 578                        DP_LANE0_1_STATUS, 2, link_status);
 579        if (retval)
 580                return retval;
 581
 582        if (exynos_dp_clock_recovery_ok(link_status, lane_count)) {
 583                exynos_dp_reduce_link_rate(dp);
 584                return -EIO;
 585        }
 586
 587        retval = exynos_dp_read_bytes_from_dpcd(dp,
 588                        DP_ADJUST_REQUEST_LANE0_1, 2, adjust_request);
 589        if (retval)
 590                return retval;
 591
 592        retval = exynos_dp_read_byte_from_dpcd(dp,
 593                        DP_LANE_ALIGN_STATUS_UPDATED, &link_align);
 594        if (retval)
 595                return retval;
 596
 597        exynos_dp_get_adjust_training_lane(dp, adjust_request);
 598
 599        if (!exynos_dp_channel_eq_ok(link_status, link_align, lane_count)) {
 600                /* traing pattern Set to Normal */
 601                exynos_dp_training_pattern_dis(dp);
 602
 603                dev_info(dp->dev, "Link Training success!\n");
 604
 605                exynos_dp_get_link_bandwidth(dp, &reg);
 606                dp->link_train.link_rate = reg;
 607                dev_dbg(dp->dev, "final bandwidth = %.2x\n",
 608                        dp->link_train.link_rate);
 609
 610                exynos_dp_get_lane_count(dp, &reg);
 611                dp->link_train.lane_count = reg;
 612                dev_dbg(dp->dev, "final lane count = %.2x\n",
 613                        dp->link_train.lane_count);
 614
 615                /* set enhanced mode if available */
 616                exynos_dp_set_enhanced_mode(dp);
 617                dp->link_train.lt_state = FINISHED;
 618
 619                return 0;
 620        }
 621
 622        /* not all locked */
 623        dp->link_train.eq_loop++;
 624
 625        if (dp->link_train.eq_loop > MAX_EQ_LOOP) {
 626                dev_err(dp->dev, "EQ Max loop\n");
 627                exynos_dp_reduce_link_rate(dp);
 628                return -EIO;
 629        }
 630
 631        for (lane = 0; lane < lane_count; lane++)
 632                exynos_dp_set_lane_link_training(dp,
 633                        dp->link_train.training_lane[lane], lane);
 634
 635        retval = exynos_dp_write_bytes_to_dpcd(dp, DP_TRAINING_LANE0_SET,
 636                        lane_count, dp->link_train.training_lane);
 637
 638        return retval;
 639}
 640
 641static void exynos_dp_get_max_rx_bandwidth(struct exynos_dp_device *dp,
 642                                        u8 *bandwidth)
 643{
 644        u8 data;
 645
 646        /*
 647         * For DP rev.1.1, Maximum link rate of Main Link lanes
 648         * 0x06 = 1.62 Gbps, 0x0a = 2.7 Gbps
 649         */
 650        exynos_dp_read_byte_from_dpcd(dp, DP_MAX_LINK_RATE, &data);
 651        *bandwidth = data;
 652}
 653
 654static void exynos_dp_get_max_rx_lane_count(struct exynos_dp_device *dp,
 655                                        u8 *lane_count)
 656{
 657        u8 data;
 658
 659        /*
 660         * For DP rev.1.1, Maximum number of Main Link lanes
 661         * 0x01 = 1 lane, 0x02 = 2 lanes, 0x04 = 4 lanes
 662         */
 663        exynos_dp_read_byte_from_dpcd(dp, DP_MAX_LANE_COUNT, &data);
 664        *lane_count = DPCD_MAX_LANE_COUNT(data);
 665}
 666
 667static void exynos_dp_init_training(struct exynos_dp_device *dp,
 668                        enum link_lane_count_type max_lane,
 669                        enum link_rate_type max_rate)
 670{
 671        /*
 672         * MACRO_RST must be applied after the PLL_LOCK to avoid
 673         * the DP inter pair skew issue for at least 10 us
 674         */
 675        exynos_dp_reset_macro(dp);
 676
 677        /* Initialize by reading RX's DPCD */
 678        exynos_dp_get_max_rx_bandwidth(dp, &dp->link_train.link_rate);
 679        exynos_dp_get_max_rx_lane_count(dp, &dp->link_train.lane_count);
 680
 681        if ((dp->link_train.link_rate != LINK_RATE_1_62GBPS) &&
 682           (dp->link_train.link_rate != LINK_RATE_2_70GBPS)) {
 683                dev_err(dp->dev, "Rx Max Link Rate is abnormal :%x !\n",
 684                        dp->link_train.link_rate);
 685                dp->link_train.link_rate = LINK_RATE_1_62GBPS;
 686        }
 687
 688        if (dp->link_train.lane_count == 0) {
 689                dev_err(dp->dev, "Rx Max Lane count is abnormal :%x !\n",
 690                        dp->link_train.lane_count);
 691                dp->link_train.lane_count = (u8)LANE_COUNT1;
 692        }
 693
 694        /* Setup TX lane count & rate */
 695        if (dp->link_train.lane_count > max_lane)
 696                dp->link_train.lane_count = max_lane;
 697        if (dp->link_train.link_rate > max_rate)
 698                dp->link_train.link_rate = max_rate;
 699
 700        /* All DP analog module power up */
 701        exynos_dp_set_analog_power_down(dp, POWER_ALL, 0);
 702}
 703
 704static int exynos_dp_sw_link_training(struct exynos_dp_device *dp)
 705{
 706        int retval = 0, training_finished = 0;
 707
 708        dp->link_train.lt_state = START;
 709
 710        /* Process here */
 711        while (!retval && !training_finished) {
 712                switch (dp->link_train.lt_state) {
 713                case START:
 714                        retval = exynos_dp_link_start(dp);
 715                        if (retval)
 716                                dev_err(dp->dev, "LT link start failed!\n");
 717                        break;
 718                case CLOCK_RECOVERY:
 719                        retval = exynos_dp_process_clock_recovery(dp);
 720                        if (retval)
 721                                dev_err(dp->dev, "LT CR failed!\n");
 722                        break;
 723                case EQUALIZER_TRAINING:
 724                        retval = exynos_dp_process_equalizer_training(dp);
 725                        if (retval)
 726                                dev_err(dp->dev, "LT EQ failed!\n");
 727                        break;
 728                case FINISHED:
 729                        training_finished = 1;
 730                        break;
 731                case FAILED:
 732                        return -EREMOTEIO;
 733                }
 734        }
 735        if (retval)
 736                dev_err(dp->dev, "eDP link training failed (%d)\n", retval);
 737
 738        return retval;
 739}
 740
 741static int exynos_dp_set_link_train(struct exynos_dp_device *dp,
 742                                u32 count,
 743                                u32 bwtype)
 744{
 745        int i;
 746        int retval;
 747
 748        for (i = 0; i < DP_TIMEOUT_LOOP_COUNT; i++) {
 749                exynos_dp_init_training(dp, count, bwtype);
 750                retval = exynos_dp_sw_link_training(dp);
 751                if (retval == 0)
 752                        break;
 753
 754                usleep_range(100, 110);
 755        }
 756
 757        return retval;
 758}
 759
 760static int exynos_dp_config_video(struct exynos_dp_device *dp)
 761{
 762        int retval = 0;
 763        int timeout_loop = 0;
 764        int done_count = 0;
 765
 766        exynos_dp_config_video_slave_mode(dp);
 767
 768        exynos_dp_set_video_color_format(dp);
 769
 770        if (exynos_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
 771                dev_err(dp->dev, "PLL is not locked yet.\n");
 772                return -EINVAL;
 773        }
 774
 775        for (;;) {
 776                timeout_loop++;
 777                if (exynos_dp_is_slave_video_stream_clock_on(dp) == 0)
 778                        break;
 779                if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
 780                        dev_err(dp->dev, "Timeout of video streamclk ok\n");
 781                        return -ETIMEDOUT;
 782                }
 783
 784                usleep_range(1, 2);
 785        }
 786
 787        /* Set to use the register calculated M/N video */
 788        exynos_dp_set_video_cr_mn(dp, CALCULATED_M, 0, 0);
 789
 790        /* For video bist, Video timing must be generated by register */
 791        exynos_dp_set_video_timing_mode(dp, VIDEO_TIMING_FROM_CAPTURE);
 792
 793        /* Disable video mute */
 794        exynos_dp_enable_video_mute(dp, 0);
 795
 796        /* Configure video slave mode */
 797        exynos_dp_enable_video_master(dp, 0);
 798
 799        timeout_loop = 0;
 800
 801        for (;;) {
 802                timeout_loop++;
 803                if (exynos_dp_is_video_stream_on(dp) == 0) {
 804                        done_count++;
 805                        if (done_count > 10)
 806                                break;
 807                } else if (done_count) {
 808                        done_count = 0;
 809                }
 810                if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
 811                        dev_err(dp->dev, "Timeout of video streamclk ok\n");
 812                        return -ETIMEDOUT;
 813                }
 814
 815                usleep_range(1000, 1001);
 816        }
 817
 818        if (retval != 0)
 819                dev_err(dp->dev, "Video stream is not detected!\n");
 820
 821        return retval;
 822}
 823
 824static void exynos_dp_enable_scramble(struct exynos_dp_device *dp, bool enable)
 825{
 826        u8 data;
 827
 828        if (enable) {
 829                exynos_dp_enable_scrambling(dp);
 830
 831                exynos_dp_read_byte_from_dpcd(dp,
 832                        DP_TRAINING_PATTERN_SET,
 833                        &data);
 834                exynos_dp_write_byte_to_dpcd(dp,
 835                        DP_TRAINING_PATTERN_SET,
 836                        (u8)(data & ~DP_LINK_SCRAMBLING_DISABLE));
 837        } else {
 838                exynos_dp_disable_scrambling(dp);
 839
 840                exynos_dp_read_byte_from_dpcd(dp,
 841                        DP_TRAINING_PATTERN_SET,
 842                        &data);
 843                exynos_dp_write_byte_to_dpcd(dp,
 844                        DP_TRAINING_PATTERN_SET,
 845                        (u8)(data | DP_LINK_SCRAMBLING_DISABLE));
 846        }
 847}
 848
 849static irqreturn_t exynos_dp_irq_handler(int irq, void *arg)
 850{
 851        struct exynos_dp_device *dp = arg;
 852
 853        enum dp_irq_type irq_type;
 854
 855        irq_type = exynos_dp_get_irq_type(dp);
 856        switch (irq_type) {
 857        case DP_IRQ_TYPE_HP_CABLE_IN:
 858                dev_dbg(dp->dev, "Received irq - cable in\n");
 859                schedule_work(&dp->hotplug_work);
 860                exynos_dp_clear_hotplug_interrupts(dp);
 861                break;
 862        case DP_IRQ_TYPE_HP_CABLE_OUT:
 863                dev_dbg(dp->dev, "Received irq - cable out\n");
 864                exynos_dp_clear_hotplug_interrupts(dp);
 865                break;
 866        case DP_IRQ_TYPE_HP_CHANGE:
 867                /*
 868                 * We get these change notifications once in a while, but there
 869                 * is nothing we can do with them. Just ignore it for now and
 870                 * only handle cable changes.
 871                 */
 872                dev_dbg(dp->dev, "Received irq - hotplug change; ignoring.\n");
 873                exynos_dp_clear_hotplug_interrupts(dp);
 874                break;
 875        default:
 876                dev_err(dp->dev, "Received irq - unknown type!\n");
 877                break;
 878        }
 879        return IRQ_HANDLED;
 880}
 881
 882static void exynos_dp_hotplug(struct work_struct *work)
 883{
 884        struct exynos_dp_device *dp;
 885
 886        dp = container_of(work, struct exynos_dp_device, hotplug_work);
 887
 888        if (dp->drm_dev)
 889                drm_helper_hpd_irq_event(dp->drm_dev);
 890}
 891
 892static void exynos_dp_commit(struct drm_encoder *encoder)
 893{
 894        struct exynos_dp_device *dp = encoder_to_dp(encoder);
 895        int ret;
 896
 897        /* Keep the panel disabled while we configure video */
 898        if (dp->panel) {
 899                if (drm_panel_disable(dp->panel))
 900                        DRM_ERROR("failed to disable the panel\n");
 901        }
 902
 903        ret = exynos_dp_detect_hpd(dp);
 904        if (ret) {
 905                /* Cable has been disconnected, we're done */
 906                return;
 907        }
 908
 909        ret = exynos_dp_handle_edid(dp);
 910        if (ret) {
 911                dev_err(dp->dev, "unable to handle edid\n");
 912                return;
 913        }
 914
 915        ret = exynos_dp_set_link_train(dp, dp->video_info->lane_count,
 916                                        dp->video_info->link_rate);
 917        if (ret) {
 918                dev_err(dp->dev, "unable to do link train\n");
 919                return;
 920        }
 921
 922        exynos_dp_enable_scramble(dp, 1);
 923        exynos_dp_enable_rx_to_enhanced_mode(dp, 1);
 924        exynos_dp_enable_enhanced_mode(dp, 1);
 925
 926        exynos_dp_set_lane_count(dp, dp->video_info->lane_count);
 927        exynos_dp_set_link_bandwidth(dp, dp->video_info->link_rate);
 928
 929        exynos_dp_init_video(dp);
 930        ret = exynos_dp_config_video(dp);
 931        if (ret)
 932                dev_err(dp->dev, "unable to config video\n");
 933
 934        /* Safe to enable the panel now */
 935        if (dp->panel) {
 936                if (drm_panel_enable(dp->panel))
 937                        DRM_ERROR("failed to enable the panel\n");
 938        }
 939
 940        /* Enable video */
 941        exynos_dp_start_video(dp);
 942}
 943
 944static enum drm_connector_status exynos_dp_detect(
 945                                struct drm_connector *connector, bool force)
 946{
 947        return connector_status_connected;
 948}
 949
 950static void exynos_dp_connector_destroy(struct drm_connector *connector)
 951{
 952        drm_connector_unregister(connector);
 953        drm_connector_cleanup(connector);
 954}
 955
 956static const struct drm_connector_funcs exynos_dp_connector_funcs = {
 957        .dpms = drm_atomic_helper_connector_dpms,
 958        .fill_modes = drm_helper_probe_single_connector_modes,
 959        .detect = exynos_dp_detect,
 960        .destroy = exynos_dp_connector_destroy,
 961        .reset = drm_atomic_helper_connector_reset,
 962        .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 963        .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 964};
 965
 966static int exynos_dp_get_modes(struct drm_connector *connector)
 967{
 968        struct exynos_dp_device *dp = ctx_from_connector(connector);
 969        struct drm_display_mode *mode;
 970
 971        if (dp->panel)
 972                return drm_panel_get_modes(dp->panel);
 973
 974        mode = drm_mode_create(connector->dev);
 975        if (!mode) {
 976                DRM_ERROR("failed to create a new display mode.\n");
 977                return 0;
 978        }
 979
 980        drm_display_mode_from_videomode(&dp->vm, mode);
 981        connector->display_info.width_mm = mode->width_mm;
 982        connector->display_info.height_mm = mode->height_mm;
 983
 984        mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
 985        drm_mode_set_name(mode);
 986        drm_mode_probed_add(connector, mode);
 987
 988        return 1;
 989}
 990
 991static struct drm_encoder *exynos_dp_best_encoder(
 992                        struct drm_connector *connector)
 993{
 994        struct exynos_dp_device *dp = ctx_from_connector(connector);
 995
 996        return &dp->encoder;
 997}
 998
 999static const struct drm_connector_helper_funcs exynos_dp_connector_helper_funcs = {
1000        .get_modes = exynos_dp_get_modes,
1001        .best_encoder = exynos_dp_best_encoder,
1002};
1003
1004/* returns the number of bridges attached */
1005static int exynos_drm_attach_lcd_bridge(struct exynos_dp_device *dp,
1006                struct drm_encoder *encoder)
1007{
1008        int ret;
1009
1010        encoder->bridge->next = dp->ptn_bridge;
1011        dp->ptn_bridge->encoder = encoder;
1012        ret = drm_bridge_attach(encoder->dev, dp->ptn_bridge);
1013        if (ret) {
1014                DRM_ERROR("Failed to attach bridge to drm\n");
1015                return ret;
1016        }
1017
1018        return 0;
1019}
1020
1021static int exynos_dp_bridge_attach(struct drm_bridge *bridge)
1022{
1023        struct exynos_dp_device *dp = bridge->driver_private;
1024        struct drm_encoder *encoder = &dp->encoder;
1025        struct drm_connector *connector = &dp->connector;
1026        int ret;
1027
1028        /* Pre-empt DP connector creation if there's a bridge */
1029        if (dp->ptn_bridge) {
1030                ret = exynos_drm_attach_lcd_bridge(dp, encoder);
1031                if (!ret)
1032                        return 0;
1033        }
1034
1035        connector->polled = DRM_CONNECTOR_POLL_HPD;
1036
1037        ret = drm_connector_init(dp->drm_dev, connector,
1038                        &exynos_dp_connector_funcs, DRM_MODE_CONNECTOR_eDP);
1039        if (ret) {
1040                DRM_ERROR("Failed to initialize connector with drm\n");
1041                return ret;
1042        }
1043
1044        drm_connector_helper_add(connector, &exynos_dp_connector_helper_funcs);
1045        drm_connector_register(connector);
1046        drm_mode_connector_attach_encoder(connector, encoder);
1047
1048        if (dp->panel)
1049                ret = drm_panel_attach(dp->panel, &dp->connector);
1050
1051        return ret;
1052}
1053
1054static void exynos_dp_bridge_enable(struct drm_bridge *bridge)
1055{
1056        struct exynos_dp_device *dp = bridge->driver_private;
1057        struct exynos_drm_crtc *crtc = dp_to_crtc(dp);
1058
1059        if (dp->dpms_mode == DRM_MODE_DPMS_ON)
1060                return;
1061
1062        pm_runtime_get_sync(dp->dev);
1063
1064        if (dp->panel) {
1065                if (drm_panel_prepare(dp->panel)) {
1066                        DRM_ERROR("failed to setup the panel\n");
1067                        return;
1068                }
1069        }
1070
1071        if (crtc->ops->clock_enable)
1072                crtc->ops->clock_enable(dp_to_crtc(dp), true);
1073
1074        phy_power_on(dp->phy);
1075        exynos_dp_init_dp(dp);
1076        enable_irq(dp->irq);
1077        exynos_dp_commit(&dp->encoder);
1078
1079        dp->dpms_mode = DRM_MODE_DPMS_ON;
1080}
1081
1082static void exynos_dp_bridge_disable(struct drm_bridge *bridge)
1083{
1084        struct exynos_dp_device *dp = bridge->driver_private;
1085        struct exynos_drm_crtc *crtc = dp_to_crtc(dp);
1086
1087        if (dp->dpms_mode != DRM_MODE_DPMS_ON)
1088                return;
1089
1090        if (dp->panel) {
1091                if (drm_panel_disable(dp->panel)) {
1092                        DRM_ERROR("failed to disable the panel\n");
1093                        return;
1094                }
1095        }
1096
1097        disable_irq(dp->irq);
1098        flush_work(&dp->hotplug_work);
1099        phy_power_off(dp->phy);
1100
1101        if (crtc->ops->clock_enable)
1102                crtc->ops->clock_enable(dp_to_crtc(dp), false);
1103
1104        if (dp->panel) {
1105                if (drm_panel_unprepare(dp->panel))
1106                        DRM_ERROR("failed to turnoff the panel\n");
1107        }
1108
1109        pm_runtime_put_sync(dp->dev);
1110
1111        dp->dpms_mode = DRM_MODE_DPMS_OFF;
1112}
1113
1114static void exynos_dp_bridge_nop(struct drm_bridge *bridge)
1115{
1116        /* do nothing */
1117}
1118
1119static const struct drm_bridge_funcs exynos_dp_bridge_funcs = {
1120        .enable = exynos_dp_bridge_enable,
1121        .disable = exynos_dp_bridge_disable,
1122        .pre_enable = exynos_dp_bridge_nop,
1123        .post_disable = exynos_dp_bridge_nop,
1124        .attach = exynos_dp_bridge_attach,
1125};
1126
1127static int exynos_dp_create_connector(struct drm_encoder *encoder)
1128{
1129        struct exynos_dp_device *dp = encoder_to_dp(encoder);
1130        struct drm_device *drm_dev = dp->drm_dev;
1131        struct drm_bridge *bridge;
1132        int ret;
1133
1134        bridge = devm_kzalloc(drm_dev->dev, sizeof(*bridge), GFP_KERNEL);
1135        if (!bridge) {
1136                DRM_ERROR("failed to allocate for drm bridge\n");
1137                return -ENOMEM;
1138        }
1139
1140        dp->bridge = bridge;
1141
1142        encoder->bridge = bridge;
1143        bridge->driver_private = dp;
1144        bridge->encoder = encoder;
1145        bridge->funcs = &exynos_dp_bridge_funcs;
1146
1147        ret = drm_bridge_attach(drm_dev, bridge);
1148        if (ret) {
1149                DRM_ERROR("failed to attach drm bridge\n");
1150                return -EINVAL;
1151        }
1152
1153        return 0;
1154}
1155
1156static void exynos_dp_mode_set(struct drm_encoder *encoder,
1157                               struct drm_display_mode *mode,
1158                               struct drm_display_mode *adjusted_mode)
1159{
1160}
1161
1162static void exynos_dp_enable(struct drm_encoder *encoder)
1163{
1164}
1165
1166static void exynos_dp_disable(struct drm_encoder *encoder)
1167{
1168}
1169
1170static const struct drm_encoder_helper_funcs exynos_dp_encoder_helper_funcs = {
1171        .mode_set = exynos_dp_mode_set,
1172        .enable = exynos_dp_enable,
1173        .disable = exynos_dp_disable,
1174};
1175
1176static const struct drm_encoder_funcs exynos_dp_encoder_funcs = {
1177        .destroy = drm_encoder_cleanup,
1178};
1179
1180static struct video_info *exynos_dp_dt_parse_pdata(struct device *dev)
1181{
1182        struct device_node *dp_node = dev->of_node;
1183        struct video_info *dp_video_config;
1184
1185        dp_video_config = devm_kzalloc(dev,
1186                                sizeof(*dp_video_config), GFP_KERNEL);
1187        if (!dp_video_config)
1188                return ERR_PTR(-ENOMEM);
1189
1190        dp_video_config->h_sync_polarity =
1191                of_property_read_bool(dp_node, "hsync-active-high");
1192
1193        dp_video_config->v_sync_polarity =
1194                of_property_read_bool(dp_node, "vsync-active-high");
1195
1196        dp_video_config->interlaced =
1197                of_property_read_bool(dp_node, "interlaced");
1198
1199        if (of_property_read_u32(dp_node, "samsung,color-space",
1200                                &dp_video_config->color_space)) {
1201                dev_err(dev, "failed to get color-space\n");
1202                return ERR_PTR(-EINVAL);
1203        }
1204
1205        if (of_property_read_u32(dp_node, "samsung,dynamic-range",
1206                                &dp_video_config->dynamic_range)) {
1207                dev_err(dev, "failed to get dynamic-range\n");
1208                return ERR_PTR(-EINVAL);
1209        }
1210
1211        if (of_property_read_u32(dp_node, "samsung,ycbcr-coeff",
1212                                &dp_video_config->ycbcr_coeff)) {
1213                dev_err(dev, "failed to get ycbcr-coeff\n");
1214                return ERR_PTR(-EINVAL);
1215        }
1216
1217        if (of_property_read_u32(dp_node, "samsung,color-depth",
1218                                &dp_video_config->color_depth)) {
1219                dev_err(dev, "failed to get color-depth\n");
1220                return ERR_PTR(-EINVAL);
1221        }
1222
1223        if (of_property_read_u32(dp_node, "samsung,link-rate",
1224                                &dp_video_config->link_rate)) {
1225                dev_err(dev, "failed to get link-rate\n");
1226                return ERR_PTR(-EINVAL);
1227        }
1228
1229        if (of_property_read_u32(dp_node, "samsung,lane-count",
1230                                &dp_video_config->lane_count)) {
1231                dev_err(dev, "failed to get lane-count\n");
1232                return ERR_PTR(-EINVAL);
1233        }
1234
1235        return dp_video_config;
1236}
1237
1238static int exynos_dp_dt_parse_panel(struct exynos_dp_device *dp)
1239{
1240        int ret;
1241
1242        ret = of_get_videomode(dp->dev->of_node, &dp->vm, OF_USE_NATIVE_MODE);
1243        if (ret) {
1244                DRM_ERROR("failed: of_get_videomode() : %d\n", ret);
1245                return ret;
1246        }
1247        return 0;
1248}
1249
1250static int exynos_dp_bind(struct device *dev, struct device *master, void *data)
1251{
1252        struct exynos_dp_device *dp = dev_get_drvdata(dev);
1253        struct platform_device *pdev = to_platform_device(dev);
1254        struct drm_device *drm_dev = data;
1255        struct drm_encoder *encoder = &dp->encoder;
1256        struct resource *res;
1257        unsigned int irq_flags;
1258        int pipe, ret = 0;
1259
1260        dp->dev = &pdev->dev;
1261        dp->dpms_mode = DRM_MODE_DPMS_OFF;
1262
1263        dp->video_info = exynos_dp_dt_parse_pdata(&pdev->dev);
1264        if (IS_ERR(dp->video_info))
1265                return PTR_ERR(dp->video_info);
1266
1267        dp->phy = devm_phy_get(dp->dev, "dp");
1268        if (IS_ERR(dp->phy)) {
1269                dev_err(dp->dev, "no DP phy configured\n");
1270                ret = PTR_ERR(dp->phy);
1271                if (ret) {
1272                        /*
1273                         * phy itself is not enabled, so we can move forward
1274                         * assigning NULL to phy pointer.
1275                         */
1276                        if (ret == -ENOSYS || ret == -ENODEV)
1277                                dp->phy = NULL;
1278                        else
1279                                return ret;
1280                }
1281        }
1282
1283        if (!dp->panel && !dp->ptn_bridge) {
1284                ret = exynos_dp_dt_parse_panel(dp);
1285                if (ret)
1286                        return ret;
1287        }
1288
1289        dp->clock = devm_clk_get(&pdev->dev, "dp");
1290        if (IS_ERR(dp->clock)) {
1291                dev_err(&pdev->dev, "failed to get clock\n");
1292                return PTR_ERR(dp->clock);
1293        }
1294
1295        clk_prepare_enable(dp->clock);
1296
1297        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1298
1299        dp->reg_base = devm_ioremap_resource(&pdev->dev, res);
1300        if (IS_ERR(dp->reg_base))
1301                return PTR_ERR(dp->reg_base);
1302
1303        dp->hpd_gpio = of_get_named_gpio(dev->of_node, "samsung,hpd-gpio", 0);
1304
1305        if (gpio_is_valid(dp->hpd_gpio)) {
1306                /*
1307                 * Set up the hotplug GPIO from the device tree as an interrupt.
1308                 * Simply specifying a different interrupt in the device tree
1309                 * doesn't work since we handle hotplug rather differently when
1310                 * using a GPIO.  We also need the actual GPIO specifier so
1311                 * that we can get the current state of the GPIO.
1312                 */
1313                ret = devm_gpio_request_one(&pdev->dev, dp->hpd_gpio, GPIOF_IN,
1314                                            "hpd_gpio");
1315                if (ret) {
1316                        dev_err(&pdev->dev, "failed to get hpd gpio\n");
1317                        return ret;
1318                }
1319                dp->irq = gpio_to_irq(dp->hpd_gpio);
1320                irq_flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
1321        } else {
1322                dp->hpd_gpio = -ENODEV;
1323                dp->irq = platform_get_irq(pdev, 0);
1324                irq_flags = 0;
1325        }
1326
1327        if (dp->irq == -ENXIO) {
1328                dev_err(&pdev->dev, "failed to get irq\n");
1329                return -ENODEV;
1330        }
1331
1332        INIT_WORK(&dp->hotplug_work, exynos_dp_hotplug);
1333
1334        ret = devm_request_irq(&pdev->dev, dp->irq, exynos_dp_irq_handler,
1335                        irq_flags, "exynos-dp", dp);
1336        if (ret) {
1337                dev_err(&pdev->dev, "failed to request irq\n");
1338                return ret;
1339        }
1340        disable_irq(dp->irq);
1341
1342        dp->drm_dev = drm_dev;
1343
1344        pipe = exynos_drm_crtc_get_pipe_from_type(drm_dev,
1345                                                  EXYNOS_DISPLAY_TYPE_LCD);
1346        if (pipe < 0)
1347                return pipe;
1348
1349        encoder->possible_crtcs = 1 << pipe;
1350
1351        DRM_DEBUG_KMS("possible_crtcs = 0x%x\n", encoder->possible_crtcs);
1352
1353        drm_encoder_init(drm_dev, encoder, &exynos_dp_encoder_funcs,
1354                         DRM_MODE_ENCODER_TMDS, NULL);
1355
1356        drm_encoder_helper_add(encoder, &exynos_dp_encoder_helper_funcs);
1357
1358        ret = exynos_dp_create_connector(encoder);
1359        if (ret) {
1360                DRM_ERROR("failed to create connector ret = %d\n", ret);
1361                drm_encoder_cleanup(encoder);
1362                return ret;
1363        }
1364
1365        return 0;
1366}
1367
1368static void exynos_dp_unbind(struct device *dev, struct device *master,
1369                                void *data)
1370{
1371        struct exynos_dp_device *dp = dev_get_drvdata(dev);
1372
1373        exynos_dp_disable(&dp->encoder);
1374}
1375
1376static const struct component_ops exynos_dp_ops = {
1377        .bind   = exynos_dp_bind,
1378        .unbind = exynos_dp_unbind,
1379};
1380
1381static int exynos_dp_probe(struct platform_device *pdev)
1382{
1383        struct device *dev = &pdev->dev;
1384        struct device_node *np = NULL, *endpoint = NULL;
1385        struct exynos_dp_device *dp;
1386        int ret;
1387
1388        dp = devm_kzalloc(&pdev->dev, sizeof(struct exynos_dp_device),
1389                                GFP_KERNEL);
1390        if (!dp)
1391                return -ENOMEM;
1392
1393        platform_set_drvdata(pdev, dp);
1394
1395        /* This is for the backward compatibility. */
1396        np = of_parse_phandle(dev->of_node, "panel", 0);
1397        if (np) {
1398                dp->panel = of_drm_find_panel(np);
1399                of_node_put(np);
1400                if (!dp->panel)
1401                        return -EPROBE_DEFER;
1402                goto out;
1403        }
1404
1405        endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
1406        if (endpoint) {
1407                np = of_graph_get_remote_port_parent(endpoint);
1408                if (np) {
1409                        /* The remote port can be either a panel or a bridge */
1410                        dp->panel = of_drm_find_panel(np);
1411                        if (!dp->panel) {
1412                                dp->ptn_bridge = of_drm_find_bridge(np);
1413                                if (!dp->ptn_bridge) {
1414                                        of_node_put(np);
1415                                        return -EPROBE_DEFER;
1416                                }
1417                        }
1418                        of_node_put(np);
1419                } else {
1420                        DRM_ERROR("no remote endpoint device node found.\n");
1421                        return -EINVAL;
1422                }
1423        } else {
1424                DRM_ERROR("no port endpoint subnode found.\n");
1425                return -EINVAL;
1426        }
1427
1428out:
1429        pm_runtime_enable(dev);
1430
1431        ret = component_add(&pdev->dev, &exynos_dp_ops);
1432        if (ret)
1433                goto err_disable_pm_runtime;
1434
1435        return ret;
1436
1437err_disable_pm_runtime:
1438        pm_runtime_disable(dev);
1439
1440        return ret;
1441}
1442
1443static int exynos_dp_remove(struct platform_device *pdev)
1444{
1445        pm_runtime_disable(&pdev->dev);
1446        component_del(&pdev->dev, &exynos_dp_ops);
1447
1448        return 0;
1449}
1450
1451#ifdef CONFIG_PM
1452static int exynos_dp_suspend(struct device *dev)
1453{
1454        struct exynos_dp_device *dp = dev_get_drvdata(dev);
1455
1456        clk_disable_unprepare(dp->clock);
1457
1458        return 0;
1459}
1460
1461static int exynos_dp_resume(struct device *dev)
1462{
1463        struct exynos_dp_device *dp = dev_get_drvdata(dev);
1464        int ret;
1465
1466        ret = clk_prepare_enable(dp->clock);
1467        if (ret < 0) {
1468                DRM_ERROR("Failed to prepare_enable the clock clk [%d]\n", ret);
1469                return ret;
1470        }
1471
1472        return 0;
1473}
1474#endif
1475
1476static const struct dev_pm_ops exynos_dp_pm_ops = {
1477        SET_RUNTIME_PM_OPS(exynos_dp_suspend, exynos_dp_resume, NULL)
1478};
1479
1480static const struct of_device_id exynos_dp_match[] = {
1481        { .compatible = "samsung,exynos5-dp" },
1482        {},
1483};
1484MODULE_DEVICE_TABLE(of, exynos_dp_match);
1485
1486struct platform_driver dp_driver = {
1487        .probe          = exynos_dp_probe,
1488        .remove         = exynos_dp_remove,
1489        .driver         = {
1490                .name   = "exynos-dp",
1491                .owner  = THIS_MODULE,
1492                .pm     = &exynos_dp_pm_ops,
1493                .of_match_table = exynos_dp_match,
1494        },
1495};
1496
1497MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
1498MODULE_DESCRIPTION("Samsung SoC DP Driver");
1499MODULE_LICENSE("GPL v2");
1500