drivers/gpu/drm/bridge/ti-sn65dsi86.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2018, The Linux Foundation. All rights reserved.
   4  */
   5
   6 #include <drm/drmP.h>
   7 #include <drm/drm_atomic.h>
   8 #include <drm/drm_atomic_helper.h>
   9 #include <drm/drm_crtc_helper.h>
  10 #include <drm/drm_dp_helper.h>
  11 #include <drm/drm_mipi_dsi.h>
  12 #include <drm/drm_of.h>
  13 #include <drm/drm_panel.h>
  14 #include <linux/clk.h>
  15 #include <linux/gpio/consumer.h>
  16 #include <linux/i2c.h>
  17 #include <linux/iopoll.h>
  18 #include <linux/of_graph.h>
  19 #include <linux/pm_runtime.h>
  20 #include <linux/regmap.h>
  21 #include <linux/regulator/consumer.h>
  22
  23 #define SN_DEVICE_REV_REG                       0x08
  24 #define SN_DPPLL_SRC_REG                        0x0A
  25 #define  DPPLL_CLK_SRC_DSICLK                   BIT(0)
  26 #define  REFCLK_FREQ_MASK                       GENMASK(3, 1)
  27 #define  REFCLK_FREQ(x)                         ((x) << 1)
  28 #define  DPPLL_SRC_DP_PLL_LOCK                  BIT(7)
  29 #define SN_PLL_ENABLE_REG                       0x0D
  30 #define SN_DSI_LANES_REG                        0x10
  31 #define  CHA_DSI_LANES_MASK                     GENMASK(4, 3)
  32 #define  CHA_DSI_LANES(x)                       ((x) << 3)
  33 #define SN_DSIA_CLK_FREQ_REG                    0x12
  34 #define SN_CHA_ACTIVE_LINE_LENGTH_LOW_REG       0x20
  35 #define SN_CHA_VERTICAL_DISPLAY_SIZE_LOW_REG    0x24
  36 #define SN_CHA_HSYNC_PULSE_WIDTH_LOW_REG        0x2C
  37 #define SN_CHA_HSYNC_PULSE_WIDTH_HIGH_REG       0x2D
  38 #define  CHA_HSYNC_POLARITY                     BIT(7)
  39 #define SN_CHA_VSYNC_PULSE_WIDTH_LOW_REG        0x30
  40 #define SN_CHA_VSYNC_PULSE_WIDTH_HIGH_REG       0x31
  41 #define  CHA_VSYNC_POLARITY                     BIT(7)
  42 #define SN_CHA_HORIZONTAL_BACK_PORCH_REG        0x34
  43 #define SN_CHA_VERTICAL_BACK_PORCH_REG          0x36
  44 #define SN_CHA_HORIZONTAL_FRONT_PORCH_REG       0x38
  45 #define SN_CHA_VERTICAL_FRONT_PORCH_REG         0x3A
  46 #define SN_ENH_FRAME_REG                        0x5A
  47 #define  VSTREAM_ENABLE                         BIT(3)
  48 #define SN_DATA_FORMAT_REG                      0x5B
  49 #define SN_HPD_DISABLE_REG                      0x5C
  50 #define  HPD_DISABLE                            BIT(0)
  51 #define SN_AUX_WDATA_REG(x)                     (0x64 + (x))
  52 #define SN_AUX_ADDR_19_16_REG                   0x74
  53 #define SN_AUX_ADDR_15_8_REG                    0x75
  54 #define SN_AUX_ADDR_7_0_REG                     0x76
  55 #define SN_AUX_LENGTH_REG                       0x77
  56 #define SN_AUX_CMD_REG                          0x78
  57 #define  AUX_CMD_SEND                           BIT(1)
  58 #define  AUX_CMD_REQ(x)                         ((x) << 4)
  59 #define SN_AUX_RDATA_REG(x)                     (0x79 + (x))
  60 #define SN_SSC_CONFIG_REG                       0x93
  61 #define  DP_NUM_LANES_MASK                      GENMASK(5, 4)
  62 #define  DP_NUM_LANES(x)                        ((x) << 4)
  63 #define SN_DATARATE_CONFIG_REG                  0x94
  64 #define  DP_DATARATE_MASK                       GENMASK(7, 5)
  65 #define  DP_DATARATE(x)                         ((x) << 5)
  66 #define SN_ML_TX_MODE_REG                       0x96
  67 #define  ML_TX_MAIN_LINK_OFF                    0
  68 #define  ML_TX_NORMAL_MODE                      BIT(0)
  69 #define SN_AUX_CMD_STATUS_REG                   0xF4
  70 #define  AUX_IRQ_STATUS_AUX_RPLY_TOUT           BIT(3)
  71 #define  AUX_IRQ_STATUS_AUX_SHORT               BIT(5)
  72 #define  AUX_IRQ_STATUS_NAT_I2C_FAIL            BIT(6)
  73
  74 #define MIN_DSI_CLK_FREQ_MHZ    40
  75
  76 /* fudge factor required to account for 8b/10b encoding */
  77 #define DP_CLK_FUDGE_NUM        10
  78 #define DP_CLK_FUDGE_DEN        8
  79
  80 /* Matches DP_AUX_MAX_PAYLOAD_BYTES (for now) */
  81 #define SN_AUX_MAX_PAYLOAD_BYTES        16
  82
  83 #define SN_REGULATOR_SUPPLY_NUM         4
  84
  85 struct ti_sn_bridge {
  86         struct device                   *dev;
  87         struct regmap                   *regmap;
  88         struct drm_dp_aux               aux;
  89         struct drm_bridge               bridge;
  90         struct drm_connector            connector;
  91         struct device_node              *host_node;
  92         struct mipi_dsi_device          *dsi;
  93         struct clk                      *refclk;
  94         struct drm_panel                *panel;
  95         struct gpio_desc                *enable_gpio;
  96         struct regulator_bulk_data      supplies[SN_REGULATOR_SUPPLY_NUM];
  97 };
  98
  99 static const struct regmap_range ti_sn_bridge_volatile_ranges[] = {
 100         { .range_min = 0, .range_max = 0xFF },
 101 };
 102
 103 static const struct regmap_access_table ti_sn_bridge_volatile_table = {
 104         .yes_ranges = ti_sn_bridge_volatile_ranges,
 105         .n_yes_ranges = ARRAY_SIZE(ti_sn_bridge_volatile_ranges),
 106 };
 107
 108 static const struct regmap_config ti_sn_bridge_regmap_config = {
 109         .reg_bits = 8,
 110         .val_bits = 8,
 111         .volatile_table = &ti_sn_bridge_volatile_table,
 112         .cache_type = REGCACHE_NONE,
 113 };
 114
 115 static void ti_sn_bridge_write_u16(struct ti_sn_bridge *pdata,
 116                                    unsigned int reg, u16 val)
 117 {
 118         regmap_write(pdata->regmap, reg, val & 0xFF);
 119         regmap_write(pdata->regmap, reg + 1, val >> 8);
 120 }
 121
 122 static int __maybe_unused ti_sn_bridge_resume(struct device *dev)
 123 {
 124         struct ti_sn_bridge *pdata = dev_get_drvdata(dev);
 125         int ret;
 126
 127         ret = regulator_bulk_enable(SN_REGULATOR_SUPPLY_NUM, pdata->supplies);
 128         if (ret) {
 129                 DRM_ERROR("failed to enable supplies %d\n", ret);
 130                 return ret;
 131         }
 132
 133         gpiod_set_value(pdata->enable_gpio, 1);
 134
 135         return ret;
 136 }
 137
 138 static int __maybe_unused ti_sn_bridge_suspend(struct device *dev)
 139 {
 140         struct ti_sn_bridge *pdata = dev_get_drvdata(dev);
 141         int ret;
 142
 143         gpiod_set_value(pdata->enable_gpio, 0);
 144
 145         ret = regulator_bulk_disable(SN_REGULATOR_SUPPLY_NUM, pdata->supplies);
 146         if (ret)
 147                 DRM_ERROR("failed to disable supplies %d\n", ret);
 148
 149         return ret;
 150 }
 151
 152 static const struct dev_pm_ops ti_sn_bridge_pm_ops = {
 153         SET_RUNTIME_PM_OPS(ti_sn_bridge_suspend, ti_sn_bridge_resume, NULL)
 154 };
 155
 156 /* Connector funcs */
 157 static struct ti_sn_bridge *
 158 connector_to_ti_sn_bridge(struct drm_connector *connector)
 159 {
 160         return container_of(connector, struct ti_sn_bridge, connector);
 161 }
 162
 163 static int ti_sn_bridge_connector_get_modes(struct drm_connector *connector)
 164 {
 165         struct ti_sn_bridge *pdata = connector_to_ti_sn_bridge(connector);
 166
 167         return drm_panel_get_modes(pdata->panel);
 168 }
 169
 170 static enum drm_mode_status
 171 ti_sn_bridge_connector_mode_valid(struct drm_connector *connector,
 172                                   struct drm_display_mode *mode)
 173 {
 174         /* maximum supported resolution is 4K at 60 fps */
 175         if (mode->clock > 594000)
 176                 return MODE_CLOCK_HIGH;
 177
 178         return MODE_OK;
 179 }
 180
 181 static struct drm_connector_helper_funcs ti_sn_bridge_connector_helper_funcs = {
 182         .get_modes = ti_sn_bridge_connector_get_modes,
 183         .mode_valid = ti_sn_bridge_connector_mode_valid,
 184 };
 185
 186 static enum drm_connector_status
 187 ti_sn_bridge_connector_detect(struct drm_connector *connector, bool force)
 188 {
 189         /**
 190          * TODO: Currently if drm_panel is present, then always
 191          * return the status as connected. Need to add support to detect
 192          * device state for hot pluggable scenarios.
 193          */
 194         return connector_status_connected;
 195 }
 196
 197 static const struct drm_connector_funcs ti_sn_bridge_connector_funcs = {
 198         .fill_modes = drm_helper_probe_single_connector_modes,
 199         .detect = ti_sn_bridge_connector_detect,
 200         .destroy = drm_connector_cleanup,
 201         .reset = drm_atomic_helper_connector_reset,
 202         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 203         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 204 };
 205
 206 static struct ti_sn_bridge *bridge_to_ti_sn_bridge(struct drm_bridge *bridge)
 207 {
 208         return container_of(bridge, struct ti_sn_bridge, bridge);
 209 }
 210
 211 static int ti_sn_bridge_parse_regulators(struct ti_sn_bridge *pdata)
 212 {
 213         unsigned int i;
 214         const char * const ti_sn_bridge_supply_names[] = {
 215                 "vcca", "vcc", "vccio", "vpll",
 216         };
 217
 218         for (i = 0; i < SN_REGULATOR_SUPPLY_NUM; i++)
 219                 pdata->supplies[i].supply = ti_sn_bridge_supply_names[i];
 220
 221         return devm_regulator_bulk_get(pdata->dev, SN_REGULATOR_SUPPLY_NUM,
 222                                        pdata->supplies);
 223 }
 224
 225 static int ti_sn_bridge_attach(struct drm_bridge *bridge)
 226 {
 227         int ret, val;
 228         struct ti_sn_bridge *pdata = bridge_to_ti_sn_bridge(bridge);
 229         struct mipi_dsi_host *host;
 230         struct mipi_dsi_device *dsi;
 231         const struct mipi_dsi_device_info info = { .type = "ti_sn_bridge",
 232                                                    .channel = 0,
 233                                                    .node = NULL,
 234                                                  };
 235
 236         ret = drm_connector_init(bridge->dev, &pdata->connector,
 237                                  &ti_sn_bridge_connector_funcs,
 238                                  DRM_MODE_CONNECTOR_eDP);
 239         if (ret) {
 240                 DRM_ERROR("Failed to initialize connector with drm\n");
 241                 return ret;
 242         }
 243
 244         drm_connector_helper_add(&pdata->connector,
 245                                  &ti_sn_bridge_connector_helper_funcs);
 246         drm_connector_attach_encoder(&pdata->connector, bridge->encoder);
 247
 248         /*
 249          * TODO: ideally finding host resource and dsi dev registration needs
 250          * to be done in bridge probe. But some existing DSI host drivers will
 251          * wait for any of the drm_bridge/drm_panel to get added to the global
 252          * bridge/panel list, before completing their probe. So if we do the
 253          * dsi dev registration part in bridge probe, before populating in
 254          * the global bridge list, then it will cause deadlock as dsi host probe
 255          * will never complete, neither our bridge probe. So keeping it here
 256          * will satisfy most of the existing host drivers. Once the host driver
 257          * is fixed we can move the below code to bridge probe safely.
 258          */
 259         host = of_find_mipi_dsi_host_by_node(pdata->host_node);
 260         if (!host) {
 261                 DRM_ERROR("failed to find dsi host\n");
 262                 ret = -ENODEV;
 263                 goto err_dsi_host;
 264         }
 265
 266         dsi = mipi_dsi_device_register_full(host, &info);
 267         if (IS_ERR(dsi)) {
 268                 DRM_ERROR("failed to create dsi device\n");
 269                 ret = PTR_ERR(dsi);
 270                 goto err_dsi_host;
 271         }
 272
 273         /* TODO: setting to 4 lanes always for now */
 274         dsi->lanes = 4;
 275         dsi->format = MIPI_DSI_FMT_RGB888;
 276         dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_SYNC_PULSE |
 277                           MIPI_DSI_MODE_EOT_PACKET | MIPI_DSI_MODE_VIDEO_HSE;
 278
 279         /* check if continuous dsi clock is required or not */
 280         pm_runtime_get_sync(pdata->dev);
 281         regmap_read(pdata->regmap, SN_DPPLL_SRC_REG, &val);
 282         pm_runtime_put(pdata->dev);
 283         if (!(val & DPPLL_CLK_SRC_DSICLK))
 284                 dsi->mode_flags |= MIPI_DSI_CLOCK_NON_CONTINUOUS;
 285
 286         ret = mipi_dsi_attach(dsi);
 287         if (ret < 0) {
 288                 DRM_ERROR("failed to attach dsi to host\n");
 289                 goto err_dsi_attach;
 290         }
 291         pdata->dsi = dsi;
 292
 293         /* attach panel to bridge */
 294         drm_panel_attach(pdata->panel, &pdata->connector);
 295
 296         return 0;
 297
 298 err_dsi_attach:
 299         mipi_dsi_device_unregister(dsi);
 300 err_dsi_host:
 301         drm_connector_cleanup(&pdata->connector);
 302         return ret;
 303 }
 304
 305 static void ti_sn_bridge_disable(struct drm_bridge *bridge)
 306 {
 307         struct ti_sn_bridge *pdata = bridge_to_ti_sn_bridge(bridge);
 308
 309         drm_panel_disable(pdata->panel);
 310
 311         /* disable video stream */
 312         regmap_update_bits(pdata->regmap, SN_ENH_FRAME_REG, VSTREAM_ENABLE, 0);
 313         /* semi auto link training mode OFF */
 314         regmap_write(pdata->regmap, SN_ML_TX_MODE_REG, 0);
 315         /* disable DP PLL */
 316         regmap_write(pdata->regmap, SN_PLL_ENABLE_REG, 0);
 317
 318         drm_panel_unprepare(pdata->panel);
 319 }
 320
 321 static u32 ti_sn_bridge_get_dsi_freq(struct ti_sn_bridge *pdata)
 322 {
 323         u32 bit_rate_khz, clk_freq_khz;
 324         struct drm_display_mode *mode =
 325                 &pdata->bridge.encoder->crtc->state->adjusted_mode;
 326
 327         bit_rate_khz = mode->clock *
 328                         mipi_dsi_pixel_format_to_bpp(pdata->dsi->format);
 329         clk_freq_khz = bit_rate_khz / (pdata->dsi->lanes * 2);
 330
 331         return clk_freq_khz;
 332 }
 333
 334 /* clk frequencies supported by bridge in Hz in case derived from REFCLK pin */
 335 static const u32 ti_sn_bridge_refclk_lut[] = {
 336         12000000,
 337         19200000,
 338         26000000,
 339         27000000,
 340         38400000,
 341 };
 342
 343 /* clk frequencies supported by bridge in Hz in case derived from DACP/N pin */
 344 static const u32 ti_sn_bridge_dsiclk_lut[] = {
 345         468000000,
 346         384000000,
 347         416000000,
 348         486000000,
 349         460800000,
 350 };
 351
 352 static void ti_sn_bridge_set_refclk_freq(struct ti_sn_bridge *pdata)
 353 {
 354         int i;
 355         u32 refclk_rate;
 356         const u32 *refclk_lut;
 357         size_t refclk_lut_size;
 358
 359         if (pdata->refclk) {
 360                 refclk_rate = clk_get_rate(pdata->refclk);
 361                 refclk_lut = ti_sn_bridge_refclk_lut;
 362                 refclk_lut_size = ARRAY_SIZE(ti_sn_bridge_refclk_lut);
 363                 clk_prepare_enable(pdata->refclk);
 364         } else {
 365                 refclk_rate = ti_sn_bridge_get_dsi_freq(pdata) * 1000;
 366                 refclk_lut = ti_sn_bridge_dsiclk_lut;
 367                 refclk_lut_size = ARRAY_SIZE(ti_sn_bridge_dsiclk_lut);
 368         }
 369
 370         /* for i equals to refclk_lut_size means default frequency */
 371         for (i = 0; i < refclk_lut_size; i++)
 372                 if (refclk_lut[i] == refclk_rate)
 373                         break;
 374
 375         regmap_update_bits(pdata->regmap, SN_DPPLL_SRC_REG, REFCLK_FREQ_MASK,
 376                            REFCLK_FREQ(i));
 377 }
 378
 379 /**
 380  * LUT index corresponds to register value and
 381  * LUT values corresponds to dp data rate supported
 382  * by the bridge in Mbps unit.
 383  */
 384 static const unsigned int ti_sn_bridge_dp_rate_lut[] = {
 385         0, 1620, 2160, 2430, 2700, 3240, 4320, 5400
 386 };
 387
 388 static void ti_sn_bridge_set_dsi_dp_rate(struct ti_sn_bridge *pdata)
 389 {
 390         unsigned int bit_rate_mhz, clk_freq_mhz, dp_rate_mhz;
 391         unsigned int val, i;
 392         struct drm_display_mode *mode =
 393                 &pdata->bridge.encoder->crtc->state->adjusted_mode;
 394
 395         /* set DSIA clk frequency */
 396         bit_rate_mhz = (mode->clock / 1000) *
 397                         mipi_dsi_pixel_format_to_bpp(pdata->dsi->format);
 398         clk_freq_mhz = bit_rate_mhz / (pdata->dsi->lanes * 2);
 399
 400         /* for each increment in val, frequency increases by 5MHz */
 401         val = (MIN_DSI_CLK_FREQ_MHZ / 5) +
 402                 (((clk_freq_mhz - MIN_DSI_CLK_FREQ_MHZ) / 5) & 0xFF);
 403         regmap_write(pdata->regmap, SN_DSIA_CLK_FREQ_REG, val);
 404
 405         /* set DP data rate */
 406         dp_rate_mhz = ((bit_rate_mhz / pdata->dsi->lanes) * DP_CLK_FUDGE_NUM) /
 407                                                         DP_CLK_FUDGE_DEN;
 408         for (i = 0; i < ARRAY_SIZE(ti_sn_bridge_dp_rate_lut) - 1; i++)
 409                 if (ti_sn_bridge_dp_rate_lut[i] > dp_rate_mhz)
 410                         break;
 411
 412         regmap_update_bits(pdata->regmap, SN_DATARATE_CONFIG_REG,
 413                            DP_DATARATE_MASK, DP_DATARATE(i));
 414 }
 415
 416 static void ti_sn_bridge_set_video_timings(struct ti_sn_bridge *pdata)
 417 {
 418         struct drm_display_mode *mode =
 419                 &pdata->bridge.encoder->crtc->state->adjusted_mode;
 420         u8 hsync_polarity = 0, vsync_polarity = 0;
 421
 422         if (mode->flags & DRM_MODE_FLAG_PHSYNC)
 423                 hsync_polarity = CHA_HSYNC_POLARITY;
 424         if (mode->flags & DRM_MODE_FLAG_PVSYNC)
 425                 vsync_polarity = CHA_VSYNC_POLARITY;
 426
 427         ti_sn_bridge_write_u16(pdata, SN_CHA_ACTIVE_LINE_LENGTH_LOW_REG,
 428                                mode->hdisplay);
 429         ti_sn_bridge_write_u16(pdata, SN_CHA_VERTICAL_DISPLAY_SIZE_LOW_REG,
 430                                mode->vdisplay);
 431         regmap_write(pdata->regmap, SN_CHA_HSYNC_PULSE_WIDTH_LOW_REG,
 432                      (mode->hsync_end - mode->hsync_start) & 0xFF);
 433         regmap_write(pdata->regmap, SN_CHA_HSYNC_PULSE_WIDTH_HIGH_REG,
 434                      (((mode->hsync_end - mode->hsync_start) >> 8) & 0x7F) |
 435                      hsync_polarity);
 436         regmap_write(pdata->regmap, SN_CHA_VSYNC_PULSE_WIDTH_LOW_REG,
 437                      (mode->vsync_end - mode->vsync_start) & 0xFF);
 438         regmap_write(pdata->regmap, SN_CHA_VSYNC_PULSE_WIDTH_HIGH_REG,
 439                      (((mode->vsync_end - mode->vsync_start) >> 8) & 0x7F) |
 440                      vsync_polarity);
 441
 442         regmap_write(pdata->regmap, SN_CHA_HORIZONTAL_BACK_PORCH_REG,
 443                      (mode->htotal - mode->hsync_end) & 0xFF);
 444         regmap_write(pdata->regmap, SN_CHA_VERTICAL_BACK_PORCH_REG,
 445                      (mode->vtotal - mode->vsync_end) & 0xFF);
 446
 447         regmap_write(pdata->regmap, SN_CHA_HORIZONTAL_FRONT_PORCH_REG,
 448                      (mode->hsync_start - mode->hdisplay) & 0xFF);
 449         regmap_write(pdata->regmap, SN_CHA_VERTICAL_FRONT_PORCH_REG,
 450                      (mode->vsync_start - mode->vdisplay) & 0xFF);
 451
 452         usleep_range(10000, 10500); /* 10ms delay recommended by spec */
 453 }
 454
 455 static void ti_sn_bridge_enable(struct drm_bridge *bridge)
 456 {
 457         struct ti_sn_bridge *pdata = bridge_to_ti_sn_bridge(bridge);
 458         unsigned int val;
 459         int ret;
 460
 461         /* DSI_A lane config */
 462         val = CHA_DSI_LANES(4 - pdata->dsi->lanes);
 463         regmap_update_bits(pdata->regmap, SN_DSI_LANES_REG,
 464                            CHA_DSI_LANES_MASK, val);
 465
 466         /* DP lane config */
 467         val = DP_NUM_LANES(pdata->dsi->lanes - 1);
 468         regmap_update_bits(pdata->regmap, SN_SSC_CONFIG_REG, DP_NUM_LANES_MASK,
 469                            val);
 470
 471         /* set dsi/dp clk frequency value */
 472         ti_sn_bridge_set_dsi_dp_rate(pdata);
 473
 474         /* enable DP PLL */
 475         regmap_write(pdata->regmap, SN_PLL_ENABLE_REG, 1);
 476
 477         ret = regmap_read_poll_timeout(pdata->regmap, SN_DPPLL_SRC_REG, val,
 478                                        val & DPPLL_SRC_DP_PLL_LOCK, 1000,
 479                                        50 * 1000);
 480         if (ret) {
 481                 DRM_ERROR("DP_PLL_LOCK polling failed (%d)\n", ret);
 482                 return;
 483         }
 484
 485         /**
 486          * The SN65DSI86 only supports ASSR Display Authentication method and
 487          * this method is enabled by default. An eDP panel must support this
 488          * authentication method. We need to enable this method in the eDP panel
 489          * at DisplayPort address 0x0010A prior to link training.
 490          */
 491         drm_dp_dpcd_writeb(&pdata->aux, DP_EDP_CONFIGURATION_SET,
 492                            DP_ALTERNATE_SCRAMBLER_RESET_ENABLE);
 493
 494         /* Semi auto link training mode */
 495         regmap_write(pdata->regmap, SN_ML_TX_MODE_REG, 0x0A);
 496         ret = regmap_read_poll_timeout(pdata->regmap, SN_ML_TX_MODE_REG, val,
 497                                        val == ML_TX_MAIN_LINK_OFF ||
 498                                        val == ML_TX_NORMAL_MODE, 1000,
 499                                        500 * 1000);
 500         if (ret) {
 501                 DRM_ERROR("Training complete polling failed (%d)\n", ret);
 502                 return;
 503         } else if (val == ML_TX_MAIN_LINK_OFF) {
 504                 DRM_ERROR("Link training failed, link is off\n");
 505                 return;
 506         }
 507
 508         /* config video parameters */
 509         ti_sn_bridge_set_video_timings(pdata);
 510
 511         /* enable video stream */
 512         regmap_update_bits(pdata->regmap, SN_ENH_FRAME_REG, VSTREAM_ENABLE,
 513                            VSTREAM_ENABLE);
 514
 515         drm_panel_enable(pdata->panel);
 516 }
 517
 518 static void ti_sn_bridge_pre_enable(struct drm_bridge *bridge)
 519 {
 520         struct ti_sn_bridge *pdata = bridge_to_ti_sn_bridge(bridge);
 521
 522         pm_runtime_get_sync(pdata->dev);
 523
 524         /* configure bridge ref_clk */
 525         ti_sn_bridge_set_refclk_freq(pdata);
 526
 527         /*
 528          * HPD on this bridge chip is a bit useless.  This is an eDP bridge
 529          * so the HPD is an internal signal that's only there to signal that
 530          * the panel is done powering up.  ...but the bridge chip debounces
 531          * this signal by between 100 ms and 400 ms (depending on process,
 532          * voltage, and temperate--I measured it at about 200 ms).  One
 533          * particular panel asserted HPD 84 ms after it was powered on meaning
 534          * that we saw HPD 284 ms after power on.  ...but the same panel said
 535          * that instead of looking at HPD you could just hardcode a delay of
 536          * 200 ms.  We'll assume that the panel driver will have the hardcoded
 537          * delay in its prepare and always disable HPD.
 538          *
 539          * If HPD somehow makes sense on some future panel we'll have to
 540          * change this to be conditional on someone specifying that HPD should
 541          * be used.
 542          */
 543         regmap_update_bits(pdata->regmap, SN_HPD_DISABLE_REG, HPD_DISABLE,
 544                            HPD_DISABLE);
 545
 546         drm_panel_prepare(pdata->panel);
 547 }
 548
 549 static void ti_sn_bridge_post_disable(struct drm_bridge *bridge)
 550 {
 551         struct ti_sn_bridge *pdata = bridge_to_ti_sn_bridge(bridge);
 552
 553         if (pdata->refclk)
 554                 clk_disable_unprepare(pdata->refclk);
 555
 556         pm_runtime_put_sync(pdata->dev);
 557 }
 558
 559 static const struct drm_bridge_funcs ti_sn_bridge_funcs = {
 560         .attach = ti_sn_bridge_attach,
 561         .pre_enable = ti_sn_bridge_pre_enable,
 562         .enable = ti_sn_bridge_enable,
 563         .disable = ti_sn_bridge_disable,
 564         .post_disable = ti_sn_bridge_post_disable,
 565 };
 566
 567 static struct ti_sn_bridge *aux_to_ti_sn_bridge(struct drm_dp_aux *aux)
 568 {
 569         return container_of(aux, struct ti_sn_bridge, aux);
 570 }
 571
 572 static ssize_t ti_sn_aux_transfer(struct drm_dp_aux *aux,
 573                                   struct drm_dp_aux_msg *msg)
 574 {
 575         struct ti_sn_bridge *pdata = aux_to_ti_sn_bridge(aux);
 576         u32 request = msg->request & ~DP_AUX_I2C_MOT;
 577         u32 request_val = AUX_CMD_REQ(msg->request);
 578         u8 *buf = (u8 *)msg->buffer;
 579         unsigned int val;
 580         int ret, i;
 581
 582         if (msg->size > SN_AUX_MAX_PAYLOAD_BYTES)
 583                 return -EINVAL;
 584
 585         switch (request) {
 586         case DP_AUX_NATIVE_WRITE:
 587         case DP_AUX_I2C_WRITE:
 588         case DP_AUX_NATIVE_READ:
 589         case DP_AUX_I2C_READ:
 590                 regmap_write(pdata->regmap, SN_AUX_CMD_REG, request_val);
 591                 break;
 592         default:
 593                 return -EINVAL;
 594         }
 595
 596         regmap_write(pdata->regmap, SN_AUX_ADDR_19_16_REG,
 597                      (msg->address >> 16) & 0xF);
 598         regmap_write(pdata->regmap, SN_AUX_ADDR_15_8_REG,
 599                      (msg->address >> 8) & 0xFF);
 600         regmap_write(pdata->regmap, SN_AUX_ADDR_7_0_REG, msg->address & 0xFF);
 601
 602         regmap_write(pdata->regmap, SN_AUX_LENGTH_REG, msg->size);
 603
 604         if (request == DP_AUX_NATIVE_WRITE || request == DP_AUX_I2C_WRITE) {
 605                 for (i = 0; i < msg->size; i++)
 606                         regmap_write(pdata->regmap, SN_AUX_WDATA_REG(i),
 607                                      buf[i]);
 608         }
 609
 610         regmap_write(pdata->regmap, SN_AUX_CMD_REG, request_val | AUX_CMD_SEND);
 611
 612         ret = regmap_read_poll_timeout(pdata->regmap, SN_AUX_CMD_REG, val,
 613                                        !(val & AUX_CMD_SEND), 200,
 614                                        50 * 1000);
 615         if (ret)
 616                 return ret;
 617
 618         ret = regmap_read(pdata->regmap, SN_AUX_CMD_STATUS_REG, &val);
 619         if (ret)
 620                 return ret;
 621         else if ((val & AUX_IRQ_STATUS_NAT_I2C_FAIL)
 622                  || (val & AUX_IRQ_STATUS_AUX_RPLY_TOUT)
 623                  || (val & AUX_IRQ_STATUS_AUX_SHORT))
 624                 return -ENXIO;
 625
 626         if (request == DP_AUX_NATIVE_WRITE || request == DP_AUX_I2C_WRITE)
 627                 return msg->size;
 628
 629         for (i = 0; i < msg->size; i++) {
 630                 unsigned int val;
 631                 ret = regmap_read(pdata->regmap, SN_AUX_RDATA_REG(i),
 632                                   &val);
 633                 if (ret)
 634                         return ret;
 635
 636                 WARN_ON(val & ~0xFF);
 637                 buf[i] = (u8)(val & 0xFF);
 638         }
 639
 640         return msg->size;
 641 }
 642
 643 static int ti_sn_bridge_parse_dsi_host(struct ti_sn_bridge *pdata)
 644 {
 645         struct device_node *np = pdata->dev->of_node;
 646
 647         pdata->host_node = of_graph_get_remote_node(np, 0, 0);
 648
 649         if (!pdata->host_node) {
 650                 DRM_ERROR("remote dsi host node not found\n");
 651                 return -ENODEV;
 652         }
 653
 654         return 0;
 655 }
 656
 657 static int ti_sn_bridge_probe(struct i2c_client *client,
 658                               const struct i2c_device_id *id)
 659 {
 660         struct ti_sn_bridge *pdata;
 661         int ret;
 662
 663         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 664                 DRM_ERROR("device doesn't support I2C\n");
 665                 return -ENODEV;
 666         }
 667
 668         pdata = devm_kzalloc(&client->dev, sizeof(struct ti_sn_bridge),
 669                              GFP_KERNEL);
 670         if (!pdata)
 671                 return -ENOMEM;
 672
 673         pdata->regmap = devm_regmap_init_i2c(client,
 674                                              &ti_sn_bridge_regmap_config);
 675         if (IS_ERR(pdata->regmap)) {
 676                 DRM_ERROR("regmap i2c init failed\n");
 677                 return PTR_ERR(pdata->regmap);
 678         }
 679
 680         pdata->dev = &client->dev;
 681
 682         ret = drm_of_find_panel_or_bridge(pdata->dev->of_node, 1, 0,
 683                                           &pdata->panel, NULL);
 684         if (ret) {
 685                 DRM_ERROR("could not find any panel node\n");
 686                 return ret;
 687         }
 688
 689         dev_set_drvdata(&client->dev, pdata);
 690
 691         pdata->enable_gpio = devm_gpiod_get(pdata->dev, "enable",
 692                                             GPIOD_OUT_LOW);
 693         if (IS_ERR(pdata->enable_gpio)) {
 694                 DRM_ERROR("failed to get enable gpio from DT\n");
 695                 ret = PTR_ERR(pdata->enable_gpio);
 696                 return ret;
 697         }
 698
 699         ret = ti_sn_bridge_parse_regulators(pdata);
 700         if (ret) {
 701                 DRM_ERROR("failed to parse regulators\n");
 702                 return ret;
 703         }
 704
 705         pdata->refclk = devm_clk_get(pdata->dev, "refclk");
 706         if (IS_ERR(pdata->refclk)) {
 707                 ret = PTR_ERR(pdata->refclk);
 708                 if (ret == -EPROBE_DEFER)
 709                         return ret;
 710                 DRM_DEBUG_KMS("refclk not found\n");
 711                 pdata->refclk = NULL;
 712         }
 713
 714         ret = ti_sn_bridge_parse_dsi_host(pdata);
 715         if (ret)
 716                 return ret;
 717
 718         pm_runtime_enable(pdata->dev);
 719
 720         i2c_set_clientdata(client, pdata);
 721
 722         pdata->aux.name = "ti-sn65dsi86-aux";
 723         pdata->aux.dev = pdata->dev;
 724         pdata->aux.transfer = ti_sn_aux_transfer;
 725         drm_dp_aux_register(&pdata->aux);
 726
 727         pdata->bridge.funcs = &ti_sn_bridge_funcs;
 728         pdata->bridge.of_node = client->dev.of_node;
 729
 730         drm_bridge_add(&pdata->bridge);
 731
 732         return 0;
 733 }
 734
 735 static int ti_sn_bridge_remove(struct i2c_client *client)
 736 {
 737         struct ti_sn_bridge *pdata = i2c_get_clientdata(client);
 738
 739         if (!pdata)
 740                 return -EINVAL;
 741
 742         of_node_put(pdata->host_node);
 743
 744         pm_runtime_disable(pdata->dev);
 745
 746         if (pdata->dsi) {
 747                 mipi_dsi_detach(pdata->dsi);
 748                 mipi_dsi_device_unregister(pdata->dsi);
 749         }
 750
 751         drm_bridge_remove(&pdata->bridge);
 752
 753         return 0;
 754 }
 755
 756 static struct i2c_device_id ti_sn_bridge_id[] = {
 757         { "ti,sn65dsi86", 0},
 758         {},
 759 };
 760 MODULE_DEVICE_TABLE(i2c, ti_sn_bridge_id);
 761
 762 static const struct of_device_id ti_sn_bridge_match_table[] = {
 763         {.compatible = "ti,sn65dsi86"},
 764         {},
 765 };
 766 MODULE_DEVICE_TABLE(of, ti_sn_bridge_match_table);
 767
 768 static struct i2c_driver ti_sn_bridge_driver = {
 769         .driver = {
 770                 .name = "ti_sn65dsi86",
 771                 .of_match_table = ti_sn_bridge_match_table,
 772                 .pm = &ti_sn_bridge_pm_ops,
 773         },
 774         .probe = ti_sn_bridge_probe,
 775         .remove = ti_sn_bridge_remove,
 776         .id_table = ti_sn_bridge_id,
 777 };
 778 module_i2c_driver(ti_sn_bridge_driver);
 779
 780 MODULE_AUTHOR("Sandeep Panda <spanda@codeaurora.org>");
 781 MODULE_DESCRIPTION("sn65dsi86 DSI to eDP bridge driver");
 782 MODULE_LICENSE("GPL v2");