drivers/gpu/drm/bridge/lontium-lt8912b.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2018, The Linux Foundation. All rights reserved.
   4  */
   5
   6 #include <linux/device.h>
   7 #include <linux/delay.h>
   8 #include <linux/gpio/consumer.h>
   9 #include <linux/i2c.h>
  10 #include <linux/media-bus-format.h>
  11 #include <linux/regmap.h>
  12
  13 #include <drm/drm_probe_helper.h>
  14 #include <drm/drm_atomic_helper.h>
  15 #include <drm/drm_edid.h>
  16 #include <drm/drm_mipi_dsi.h>
  17 #include <drm/drm_of.h>
  18
  19 #include <video/videomode.h>
  20
  21 #define I2C_MAIN 0
  22 #define I2C_ADDR_MAIN 0x48
  23
  24 #define I2C_CEC_DSI 1
  25 #define I2C_ADDR_CEC_DSI 0x49
  26
  27 #define I2C_MAX_IDX 2
  28
  29 struct lt8912 {
  30         struct device *dev;
  31         struct drm_bridge bridge;
  32         struct drm_connector connector;
  33
  34         struct i2c_client *i2c_client[I2C_MAX_IDX];
  35         struct regmap *regmap[I2C_MAX_IDX];
  36
  37         struct device_node *host_node;
  38         struct drm_bridge *hdmi_port;
  39
  40         struct mipi_dsi_device *dsi;
  41
  42         struct gpio_desc *gp_reset;
  43
  44         struct videomode mode;
  45
  46         u8 data_lanes;
  47         bool is_power_on;
  48 };
  49
  50 static int lt8912_write_init_config(struct lt8912 *lt)
  51 {
  52         const struct reg_sequence seq[] = {
  53                 /* Digital clock en*/
  54                 {0x08, 0xff},
  55                 {0x09, 0xff},
  56                 {0x0a, 0xff},
  57                 {0x0b, 0x7c},
  58                 {0x0c, 0xff},
  59                 {0x42, 0x04},
  60
  61                 /*Tx Analog*/
  62                 {0x31, 0xb1},
  63                 {0x32, 0xb1},
  64                 {0x33, 0x0e},
  65                 {0x37, 0x00},
  66                 {0x38, 0x22},
  67                 {0x60, 0x82},
  68
  69                 /*Cbus Analog*/
  70                 {0x39, 0x45},
  71                 {0x3a, 0x00},
  72                 {0x3b, 0x00},
  73
  74                 /*HDMI Pll Analog*/
  75                 {0x44, 0x31},
  76                 {0x55, 0x44},
  77                 {0x57, 0x01},
  78                 {0x5a, 0x02},
  79
  80                 /*MIPI Analog*/
  81                 {0x3e, 0xd6},
  82                 {0x3f, 0xd4},
  83                 {0x41, 0x3c},
  84                 {0xB2, 0x00},
  85         };
  86
  87         return regmap_multi_reg_write(lt->regmap[I2C_MAIN], seq, ARRAY_SIZE(seq));
  88 }
  89
  90 static int lt8912_write_mipi_basic_config(struct lt8912 *lt)
  91 {
  92         const struct reg_sequence seq[] = {
  93                 {0x12, 0x04},
  94                 {0x14, 0x00},
  95                 {0x15, 0x00},
  96                 {0x1a, 0x03},
  97                 {0x1b, 0x03},
  98         };
  99
 100         return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq));
 101 };
 102
 103 static int lt8912_write_dds_config(struct lt8912 *lt)
 104 {
 105         const struct reg_sequence seq[] = {
 106                 {0x4e, 0xff},
 107                 {0x4f, 0x56},
 108                 {0x50, 0x69},
 109                 {0x51, 0x80},
 110                 {0x1f, 0x5e},
 111                 {0x20, 0x01},
 112                 {0x21, 0x2c},
 113                 {0x22, 0x01},
 114                 {0x23, 0xfa},
 115                 {0x24, 0x00},
 116                 {0x25, 0xc8},
 117                 {0x26, 0x00},
 118                 {0x27, 0x5e},
 119                 {0x28, 0x01},
 120                 {0x29, 0x2c},
 121                 {0x2a, 0x01},
 122                 {0x2b, 0xfa},
 123                 {0x2c, 0x00},
 124                 {0x2d, 0xc8},
 125                 {0x2e, 0x00},
 126                 {0x42, 0x64},
 127                 {0x43, 0x00},
 128                 {0x44, 0x04},
 129                 {0x45, 0x00},
 130                 {0x46, 0x59},
 131                 {0x47, 0x00},
 132                 {0x48, 0xf2},
 133                 {0x49, 0x06},
 134                 {0x4a, 0x00},
 135                 {0x4b, 0x72},
 136                 {0x4c, 0x45},
 137                 {0x4d, 0x00},
 138                 {0x52, 0x08},
 139                 {0x53, 0x00},
 140                 {0x54, 0xb2},
 141                 {0x55, 0x00},
 142                 {0x56, 0xe4},
 143                 {0x57, 0x0d},
 144                 {0x58, 0x00},
 145                 {0x59, 0xe4},
 146                 {0x5a, 0x8a},
 147                 {0x5b, 0x00},
 148                 {0x5c, 0x34},
 149                 {0x1e, 0x4f},
 150                 {0x51, 0x00},
 151         };
 152
 153         return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq));
 154 }
 155
 156 static int lt8912_write_rxlogicres_config(struct lt8912 *lt)
 157 {
 158         int ret;
 159
 160         ret = regmap_write(lt->regmap[I2C_MAIN], 0x03, 0x7f);
 161         usleep_range(10000, 20000);
 162         ret |= regmap_write(lt->regmap[I2C_MAIN], 0x03, 0xff);
 163
 164         return ret;
 165 };
 166
 167 /* enable LVDS output with some hardcoded configuration, not required for the HDMI output */
 168 static int lt8912_write_lvds_config(struct lt8912 *lt)
 169 {
 170         const struct reg_sequence seq[] = {
 171                 // lvds power up
 172                 {0x44, 0x30},
 173                 {0x51, 0x05},
 174
 175                 // core pll bypass
 176                 {0x50, 0x24}, // cp=50uA
 177                 {0x51, 0x2d}, // Pix_clk as reference, second order passive LPF PLL
 178                 {0x52, 0x04}, // loopdiv=0, use second-order PLL
 179                 {0x69, 0x0e}, // CP_PRESET_DIV_RATIO
 180                 {0x69, 0x8e},
 181                 {0x6a, 0x00},
 182                 {0x6c, 0xb8}, // RGD_CP_SOFT_K_EN,RGD_CP_SOFT_K[13:8]
 183                 {0x6b, 0x51},
 184
 185                 {0x04, 0xfb}, // core pll reset
 186                 {0x04, 0xff},
 187
 188                 // scaler bypass
 189                 {0x7f, 0x00}, // disable scaler
 190                 {0xa8, 0x13}, // 0x13: JEIDA, 0x33: VESA
 191
 192                 {0x02, 0xf7}, // lvds pll reset
 193                 {0x02, 0xff},
 194                 {0x03, 0xcf},
 195                 {0x03, 0xff},
 196         };
 197
 198         return regmap_multi_reg_write(lt->regmap[I2C_MAIN], seq, ARRAY_SIZE(seq));
 199 };
 200
 201 static inline struct lt8912 *bridge_to_lt8912(struct drm_bridge *b)
 202 {
 203         return container_of(b, struct lt8912, bridge);
 204 }
 205
 206 static inline struct lt8912 *connector_to_lt8912(struct drm_connector *c)
 207 {
 208         return container_of(c, struct lt8912, connector);
 209 }
 210
 211 static const struct regmap_config lt8912_regmap_config = {
 212         .reg_bits = 8,
 213         .val_bits = 8,
 214         .max_register = 0xff,
 215 };
 216
 217 static int lt8912_init_i2c(struct lt8912 *lt, struct i2c_client *client)
 218 {
 219         unsigned int i;
 220         /*
 221          * At this time we only initialize 2 chips, but the lt8912 provides
 222          * a third interface for the audio over HDMI configuration.
 223          */
 224         struct i2c_board_info info[] = {
 225                 { I2C_BOARD_INFO("lt8912p0", I2C_ADDR_MAIN), },
 226                 { I2C_BOARD_INFO("lt8912p1", I2C_ADDR_CEC_DSI), },
 227         };
 228
 229         if (!lt)
 230                 return -ENODEV;
 231
 232         for (i = 0; i < ARRAY_SIZE(info); i++) {
 233                 if (i > 0) {
 234                         lt->i2c_client[i] = i2c_new_dummy_device(client->adapter,
 235                                                                  info[i].addr);
 236                         if (IS_ERR(lt->i2c_client[i]))
 237                                 return PTR_ERR(lt->i2c_client[i]);
 238                 }
 239
 240                 lt->regmap[i] = devm_regmap_init_i2c(lt->i2c_client[i],
 241                                                      &lt8912_regmap_config);
 242                 if (IS_ERR(lt->regmap[i]))
 243                         return PTR_ERR(lt->regmap[i]);
 244         }
 245         return 0;
 246 }
 247
 248 static int lt8912_free_i2c(struct lt8912 *lt)
 249 {
 250         unsigned int i;
 251
 252         for (i = 1; i < I2C_MAX_IDX; i++)
 253                 i2c_unregister_device(lt->i2c_client[i]);
 254
 255         return 0;
 256 }
 257
 258 static int lt8912_hard_power_on(struct lt8912 *lt)
 259 {
 260         gpiod_set_value_cansleep(lt->gp_reset, 0);
 261         msleep(20);
 262
 263         return 0;
 264 }
 265
 266 static void lt8912_hard_power_off(struct lt8912 *lt)
 267 {
 268         gpiod_set_value_cansleep(lt->gp_reset, 1);
 269         msleep(20);
 270         lt->is_power_on = false;
 271 }
 272
 273 static int lt8912_video_setup(struct lt8912 *lt)
 274 {
 275         u32 hactive, h_total, hpw, hfp, hbp;
 276         u32 vactive, v_total, vpw, vfp, vbp;
 277         u8 settle = 0x08;
 278         int ret, hsync_activehigh, vsync_activehigh;
 279
 280         if (!lt)
 281                 return -EINVAL;
 282
 283         hactive = lt->mode.hactive;
 284         hfp = lt->mode.hfront_porch;
 285         hpw = lt->mode.hsync_len;
 286         hbp = lt->mode.hback_porch;
 287         h_total = hactive + hfp + hpw + hbp;
 288         hsync_activehigh = lt->mode.flags & DISPLAY_FLAGS_HSYNC_HIGH;
 289
 290         vactive = lt->mode.vactive;
 291         vfp = lt->mode.vfront_porch;
 292         vpw = lt->mode.vsync_len;
 293         vbp = lt->mode.vback_porch;
 294         v_total = vactive + vfp + vpw + vbp;
 295         vsync_activehigh = lt->mode.flags & DISPLAY_FLAGS_VSYNC_HIGH;
 296
 297         if (vactive <= 600)
 298                 settle = 0x04;
 299         else if (vactive == 1080)
 300                 settle = 0x0a;
 301
 302         ret = regmap_write(lt->regmap[I2C_CEC_DSI], 0x10, 0x01);
 303         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x11, settle);
 304         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x18, hpw);
 305         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x19, vpw);
 306         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x1c, hactive & 0xff);
 307         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x1d, hactive >> 8);
 308
 309         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x2f, 0x0c);
 310
 311         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x34, h_total & 0xff);
 312         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x35, h_total >> 8);
 313
 314         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x36, v_total & 0xff);
 315         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x37, v_total >> 8);
 316
 317         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x38, vbp & 0xff);
 318         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x39, vbp >> 8);
 319
 320         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3a, vfp & 0xff);
 321         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3b, vfp >> 8);
 322
 323         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3c, hbp & 0xff);
 324         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3d, hbp >> 8);
 325
 326         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3e, hfp & 0xff);
 327         ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3f, hfp >> 8);
 328
 329         ret |= regmap_update_bits(lt->regmap[I2C_MAIN], 0xab, BIT(0),
 330                                   vsync_activehigh ? BIT(0) : 0);
 331         ret |= regmap_update_bits(lt->regmap[I2C_MAIN], 0xab, BIT(1),
 332                                   hsync_activehigh ? BIT(1) : 0);
 333         ret |= regmap_update_bits(lt->regmap[I2C_MAIN], 0xb2, BIT(0),
 334                                   lt->connector.display_info.is_hdmi ? BIT(0) : 0);
 335
 336         return ret;
 337 }
 338
 339 static int lt8912_soft_power_on(struct lt8912 *lt)
 340 {
 341         if (!lt->is_power_on) {
 342                 u32 lanes = lt->data_lanes;
 343
 344                 lt8912_write_init_config(lt);
 345                 regmap_write(lt->regmap[I2C_CEC_DSI], 0x13, lanes & 3);
 346
 347                 lt8912_write_mipi_basic_config(lt);
 348
 349                 lt->is_power_on = true;
 350         }
 351
 352         return 0;
 353 }
 354
 355 static int lt8912_video_on(struct lt8912 *lt)
 356 {
 357         int ret;
 358
 359         ret = lt8912_video_setup(lt);
 360         if (ret < 0)
 361                 goto end;
 362
 363         ret = lt8912_write_dds_config(lt);
 364         if (ret < 0)
 365                 goto end;
 366
 367         ret = lt8912_write_rxlogicres_config(lt);
 368         if (ret < 0)
 369                 goto end;
 370
 371         ret = lt8912_write_lvds_config(lt);
 372         if (ret < 0)
 373                 goto end;
 374
 375 end:
 376         return ret;
 377 }
 378
 379 static enum drm_connector_status lt8912_check_cable_status(struct lt8912 *lt)
 380 {
 381         int ret;
 382         unsigned int reg_val;
 383
 384         ret = regmap_read(lt->regmap[I2C_MAIN], 0xC1, &reg_val);
 385         if (ret)
 386                 return connector_status_unknown;
 387
 388         if (reg_val & BIT(7))
 389                 return connector_status_connected;
 390
 391         return connector_status_disconnected;
 392 }
 393
 394 static enum drm_connector_status
 395 lt8912_connector_detect(struct drm_connector *connector, bool force)
 396 {
 397         struct lt8912 *lt = connector_to_lt8912(connector);
 398
 399         if (lt->hdmi_port->ops & DRM_BRIDGE_OP_DETECT)
 400                 return drm_bridge_detect(lt->hdmi_port);
 401
 402         return lt8912_check_cable_status(lt);
 403 }
 404
 405 static const struct drm_connector_funcs lt8912_connector_funcs = {
 406         .detect = lt8912_connector_detect,
 407         .fill_modes = drm_helper_probe_single_connector_modes,
 408         .destroy = drm_connector_cleanup,
 409         .reset = drm_atomic_helper_connector_reset,
 410         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 411         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 412 };
 413
 414 static enum drm_mode_status
 415 lt8912_connector_mode_valid(struct drm_connector *connector,
 416                             struct drm_display_mode *mode)
 417 {
 418         if (mode->clock > 150000)
 419                 return MODE_CLOCK_HIGH;
 420
 421         if (mode->hdisplay > 1920)
 422                 return MODE_BAD_HVALUE;
 423
 424         if (mode->vdisplay > 1080)
 425                 return MODE_BAD_VVALUE;
 426
 427         return MODE_OK;
 428 }
 429
 430 static int lt8912_connector_get_modes(struct drm_connector *connector)
 431 {
 432         struct edid *edid;
 433         int ret = -1;
 434         int num = 0;
 435         struct lt8912 *lt = connector_to_lt8912(connector);
 436         u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
 437
 438         edid = drm_bridge_get_edid(lt->hdmi_port, connector);
 439         if (edid) {
 440                 drm_connector_update_edid_property(connector, edid);
 441                 num = drm_add_edid_modes(connector, edid);
 442         } else {
 443                 return ret;
 444         }
 445
 446         ret = drm_display_info_set_bus_formats(&connector->display_info,
 447                                                &bus_format, 1);
 448         if (ret)
 449                 num = ret;
 450
 451         kfree(edid);
 452         return num;
 453 }
 454
 455 static const struct drm_connector_helper_funcs lt8912_connector_helper_funcs = {
 456         .get_modes = lt8912_connector_get_modes,
 457         .mode_valid = lt8912_connector_mode_valid,
 458 };
 459
 460 static void lt8912_bridge_mode_set(struct drm_bridge *bridge,
 461                                    const struct drm_display_mode *mode,
 462                                    const struct drm_display_mode *adj)
 463 {
 464         struct lt8912 *lt = bridge_to_lt8912(bridge);
 465
 466         drm_display_mode_to_videomode(adj, &lt->mode);
 467 }
 468
 469 static void lt8912_bridge_enable(struct drm_bridge *bridge)
 470 {
 471         struct lt8912 *lt = bridge_to_lt8912(bridge);
 472
 473         lt8912_video_on(lt);
 474 }
 475
 476 static int lt8912_attach_dsi(struct lt8912 *lt)
 477 {
 478         struct device *dev = lt->dev;
 479         struct mipi_dsi_host *host;
 480         struct mipi_dsi_device *dsi;
 481         int ret = -1;
 482         const struct mipi_dsi_device_info info = { .type = "lt8912",
 483                                                    .channel = 0,
 484                                                    .node = NULL,
 485                                                  };
 486
 487         host = of_find_mipi_dsi_host_by_node(lt->host_node);
 488         if (!host) {
 489                 dev_err(dev, "failed to find dsi host\n");
 490                 return -EPROBE_DEFER;
 491         }
 492
 493         dsi = devm_mipi_dsi_device_register_full(dev, host, &info);
 494         if (IS_ERR(dsi)) {
 495                 ret = PTR_ERR(dsi);
 496                 dev_err(dev, "failed to create dsi device (%d)\n", ret);
 497                 return ret;
 498         }
 499
 500         lt->dsi = dsi;
 501
 502         dsi->lanes = lt->data_lanes;
 503         dsi->format = MIPI_DSI_FMT_RGB888;
 504
 505         dsi->mode_flags = MIPI_DSI_MODE_VIDEO |
 506                           MIPI_DSI_MODE_LPM |
 507                           MIPI_DSI_MODE_NO_EOT_PACKET;
 508
 509         ret = devm_mipi_dsi_attach(dev, dsi);
 510         if (ret < 0) {
 511                 dev_err(dev, "failed to attach dsi to host\n");
 512                 return ret;
 513         }
 514
 515         return 0;
 516 }
 517
 518 static void lt8912_bridge_hpd_cb(void *data, enum drm_connector_status status)
 519 {
 520         struct lt8912 *lt = data;
 521
 522         if (lt->bridge.dev)
 523                 drm_helper_hpd_irq_event(lt->bridge.dev);
 524 }
 525
 526 static int lt8912_bridge_connector_init(struct drm_bridge *bridge)
 527 {
 528         int ret;
 529         struct lt8912 *lt = bridge_to_lt8912(bridge);
 530         struct drm_connector *connector = &lt->connector;
 531
 532         if (lt->hdmi_port->ops & DRM_BRIDGE_OP_HPD) {
 533                 drm_bridge_hpd_enable(lt->hdmi_port, lt8912_bridge_hpd_cb, lt);
 534                 connector->polled = DRM_CONNECTOR_POLL_HPD;
 535         } else {
 536                 connector->polled = DRM_CONNECTOR_POLL_CONNECT |
 537                                     DRM_CONNECTOR_POLL_DISCONNECT;
 538         }
 539
 540         ret = drm_connector_init(bridge->dev, connector,
 541                                  &lt8912_connector_funcs,
 542                                  lt->hdmi_port->type);
 543         if (ret)
 544                 goto exit;
 545
 546         drm_connector_helper_add(connector, &lt8912_connector_helper_funcs);
 547
 548         connector->dpms = DRM_MODE_DPMS_OFF;
 549         drm_connector_attach_encoder(connector, bridge->encoder);
 550
 551 exit:
 552         return ret;
 553 }
 554
 555 static int lt8912_bridge_attach(struct drm_bridge *bridge,
 556                                 enum drm_bridge_attach_flags flags)
 557 {
 558         struct lt8912 *lt = bridge_to_lt8912(bridge);
 559         int ret;
 560
 561         ret = drm_bridge_attach(bridge->encoder, lt->hdmi_port, bridge,
 562                                 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
 563         if (ret < 0) {
 564                 dev_err(lt->dev, "Failed to attach next bridge (%d)\n", ret);
 565                 return ret;
 566         }
 567
 568         if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)) {
 569                 ret = lt8912_bridge_connector_init(bridge);
 570                 if (ret) {
 571                         dev_err(lt->dev, "Failed to init bridge ! (%d)\n", ret);
 572                         return ret;
 573                 }
 574         }
 575
 576         ret = lt8912_hard_power_on(lt);
 577         if (ret)
 578                 return ret;
 579
 580         ret = lt8912_soft_power_on(lt);
 581         if (ret)
 582                 goto error;
 583
 584         return 0;
 585
 586 error:
 587         lt8912_hard_power_off(lt);
 588         return ret;
 589 }
 590
 591 static void lt8912_bridge_detach(struct drm_bridge *bridge)
 592 {
 593         struct lt8912 *lt = bridge_to_lt8912(bridge);
 594
 595         lt8912_hard_power_off(lt);
 596
 597         if (lt->connector.dev && lt->hdmi_port->ops & DRM_BRIDGE_OP_HPD)
 598                 drm_bridge_hpd_disable(lt->hdmi_port);
 599 }
 600
 601 static enum drm_connector_status
 602 lt8912_bridge_detect(struct drm_bridge *bridge)
 603 {
 604         struct lt8912 *lt = bridge_to_lt8912(bridge);
 605
 606         if (lt->hdmi_port->ops & DRM_BRIDGE_OP_DETECT)
 607                 return drm_bridge_detect(lt->hdmi_port);
 608
 609         return lt8912_check_cable_status(lt);
 610 }
 611
 612 static struct edid *lt8912_bridge_get_edid(struct drm_bridge *bridge,
 613                                            struct drm_connector *connector)
 614 {
 615         struct lt8912 *lt = bridge_to_lt8912(bridge);
 616
 617         /*
 618          * edid must be read through the ddc bus but it must be
 619          * given to the hdmi connector node.
 620          */
 621         if (lt->hdmi_port->ops & DRM_BRIDGE_OP_EDID)
 622                 return drm_bridge_get_edid(lt->hdmi_port, connector);
 623
 624         dev_warn(lt->dev, "The connected bridge does not supports DRM_BRIDGE_OP_EDID\n");
 625         return NULL;
 626 }
 627
 628 static const struct drm_bridge_funcs lt8912_bridge_funcs = {
 629         .attach = lt8912_bridge_attach,
 630         .detach = lt8912_bridge_detach,
 631         .mode_set = lt8912_bridge_mode_set,
 632         .enable = lt8912_bridge_enable,
 633         .detect = lt8912_bridge_detect,
 634         .get_edid = lt8912_bridge_get_edid,
 635 };
 636
 637 static int lt8912_parse_dt(struct lt8912 *lt)
 638 {
 639         struct gpio_desc *gp_reset;
 640         struct device *dev = lt->dev;
 641         int ret;
 642         int data_lanes;
 643         struct device_node *port_node;
 644
 645         gp_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
 646         if (IS_ERR(gp_reset)) {
 647                 ret = PTR_ERR(gp_reset);
 648                 if (ret != -EPROBE_DEFER)
 649                         dev_err(dev, "Failed to get reset gpio: %d\n", ret);
 650                 return ret;
 651         }
 652         lt->gp_reset = gp_reset;
 653
 654         data_lanes = drm_of_get_data_lanes_count_ep(dev->of_node, 0, -1, 1, 4);
 655         if (data_lanes < 0) {
 656                 dev_err(lt->dev, "%s: Bad data-lanes property\n", __func__);
 657                 return data_lanes;
 658         }
 659
 660         lt->data_lanes = data_lanes;
 661
 662         lt->host_node = of_graph_get_remote_node(dev->of_node, 0, -1);
 663         if (!lt->host_node) {
 664                 dev_err(lt->dev, "%s: Failed to get remote port\n", __func__);
 665                 return -ENODEV;
 666         }
 667
 668         port_node = of_graph_get_remote_node(dev->of_node, 1, -1);
 669         if (!port_node) {
 670                 dev_err(lt->dev, "%s: Failed to get connector port\n", __func__);
 671                 ret = -ENODEV;
 672                 goto err_free_host_node;
 673         }
 674
 675         lt->hdmi_port = of_drm_find_bridge(port_node);
 676         if (!lt->hdmi_port) {
 677                 ret = -EPROBE_DEFER;
 678                 dev_err_probe(lt->dev, ret, "%s: Failed to get hdmi port\n", __func__);
 679                 goto err_free_host_node;
 680         }
 681
 682         if (!of_device_is_compatible(port_node, "hdmi-connector")) {
 683                 dev_err(lt->dev, "%s: Failed to get hdmi port\n", __func__);
 684                 ret = -EINVAL;
 685                 goto err_free_host_node;
 686         }
 687
 688         of_node_put(port_node);
 689         return 0;
 690
 691 err_free_host_node:
 692         of_node_put(port_node);
 693         of_node_put(lt->host_node);
 694         return ret;
 695 }
 696
 697 static int lt8912_put_dt(struct lt8912 *lt)
 698 {
 699         of_node_put(lt->host_node);
 700         return 0;
 701 }
 702
 703 static int lt8912_probe(struct i2c_client *client)
 704 {
 705         static struct lt8912 *lt;
 706         int ret = 0;
 707         struct device *dev = &client->dev;
 708
 709         lt = devm_kzalloc(dev, sizeof(struct lt8912), GFP_KERNEL);
 710         if (!lt)
 711                 return -ENOMEM;
 712
 713         lt->dev = dev;
 714         lt->i2c_client[0] = client;
 715
 716         ret = lt8912_parse_dt(lt);
 717         if (ret)
 718                 goto err_dt_parse;
 719
 720         ret = lt8912_init_i2c(lt, client);
 721         if (ret)
 722                 goto err_i2c;
 723
 724         i2c_set_clientdata(client, lt);
 725
 726         lt->bridge.funcs = &lt8912_bridge_funcs;
 727         lt->bridge.of_node = dev->of_node;
 728         lt->bridge.ops = (DRM_BRIDGE_OP_EDID |
 729                           DRM_BRIDGE_OP_DETECT);
 730
 731         drm_bridge_add(&lt->bridge);
 732
 733         ret = lt8912_attach_dsi(lt);
 734         if (ret)
 735                 goto err_attach;
 736
 737         return 0;
 738
 739 err_attach:
 740         drm_bridge_remove(&lt->bridge);
 741         lt8912_free_i2c(lt);
 742 err_i2c:
 743         lt8912_put_dt(lt);
 744 err_dt_parse:
 745         return ret;
 746 }
 747
 748 static void lt8912_remove(struct i2c_client *client)
 749 {
 750         struct lt8912 *lt = i2c_get_clientdata(client);
 751
 752         drm_bridge_remove(&lt->bridge);
 753         lt8912_free_i2c(lt);
 754         lt8912_put_dt(lt);
 755 }
 756
 757 static const struct of_device_id lt8912_dt_match[] = {
 758         {.compatible = "lontium,lt8912b"},
 759         {}
 760 };
 761 MODULE_DEVICE_TABLE(of, lt8912_dt_match);
 762
 763 static const struct i2c_device_id lt8912_id[] = {
 764         {"lt8912", 0},
 765         {},
 766 };
 767 MODULE_DEVICE_TABLE(i2c, lt8912_id);
 768
 769 static struct i2c_driver lt8912_i2c_driver = {
 770         .driver = {
 771                 .name = "lt8912",
 772                 .of_match_table = lt8912_dt_match,
 773         },
 774         .probe = lt8912_probe,
 775         .remove = lt8912_remove,
 776         .id_table = lt8912_id,
 777 };
 778 module_i2c_driver(lt8912_i2c_driver);
 779
 780 MODULE_AUTHOR("Adrien Grassein <adrien.grassein@gmail.com>");
 781 MODULE_DESCRIPTION("lt8912 drm driver");
 782 MODULE_LICENSE("GPL v2");