drivers/gpu/drm/imx/imx-ldb.c

   1 /*
   2  * i.MX drm driver - LVDS display bridge
   3  *
   4  * Copyright (C) 2012 Sascha Hauer, Pengutronix
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version 2
   9  * of the License, or (at your option) any later version.
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/clk.h>
  18 #include <linux/component.h>
  19 #include <drm/drmP.h>
  20 #include <drm/drm_atomic_helper.h>
  21 #include <drm/drm_fb_helper.h>
  22 #include <drm/drm_crtc_helper.h>
  23 #include <drm/drm_of.h>
  24 #include <drm/drm_panel.h>
  25 #include <linux/mfd/syscon.h>
  26 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
  27 #include <linux/of_device.h>
  28 #include <linux/of_graph.h>
  29 #include <video/of_display_timing.h>
  30 #include <video/of_videomode.h>
  31 #include <linux/regmap.h>
  32 #include <linux/videodev2.h>
  33
  34 #include "imx-drm.h"
  35
  36 #define DRIVER_NAME "imx-ldb"
  37
  38 #define LDB_CH0_MODE_EN_TO_DI0          (1 << 0)
  39 #define LDB_CH0_MODE_EN_TO_DI1          (3 << 0)
  40 #define LDB_CH0_MODE_EN_MASK            (3 << 0)
  41 #define LDB_CH1_MODE_EN_TO_DI0          (1 << 2)
  42 #define LDB_CH1_MODE_EN_TO_DI1          (3 << 2)
  43 #define LDB_CH1_MODE_EN_MASK            (3 << 2)
  44 #define LDB_SPLIT_MODE_EN               (1 << 4)
  45 #define LDB_DATA_WIDTH_CH0_24           (1 << 5)
  46 #define LDB_BIT_MAP_CH0_JEIDA           (1 << 6)
  47 #define LDB_DATA_WIDTH_CH1_24           (1 << 7)
  48 #define LDB_BIT_MAP_CH1_JEIDA           (1 << 8)
  49 #define LDB_DI0_VS_POL_ACT_LOW          (1 << 9)
  50 #define LDB_DI1_VS_POL_ACT_LOW          (1 << 10)
  51 #define LDB_BGREF_RMODE_INT             (1 << 15)
  52
  53 #define con_to_imx_ldb_ch(x) container_of(x, struct imx_ldb_channel, connector)
  54 #define enc_to_imx_ldb_ch(x) container_of(x, struct imx_ldb_channel, encoder)
  55
  56 struct imx_ldb;
  57
  58 struct imx_ldb_channel {
  59         struct imx_ldb *ldb;
  60         struct drm_connector connector;
  61         struct drm_encoder encoder;
  62         struct drm_panel *panel;
  63         struct device_node *child;
  64         struct i2c_adapter *ddc;
  65         int chno;
  66         void *edid;
  67         int edid_len;
  68         struct drm_display_mode mode;
  69         int mode_valid;
  70         int bus_format;
  71 };
  72
  73 struct bus_mux {
  74         int reg;
  75         int shift;
  76         int mask;
  77 };
  78
  79 struct imx_ldb {
  80         struct regmap *regmap;
  81         struct device *dev;
  82         struct imx_ldb_channel channel[2];
  83         struct clk *clk[2]; /* our own clock */
  84         struct clk *clk_sel[4]; /* parent of display clock */
  85         struct clk *clk_parent[4]; /* original parent of clk_sel */
  86         struct clk *clk_pll[2]; /* upstream clock we can adjust */
  87         u32 ldb_ctrl;
  88         const struct bus_mux *lvds_mux;
  89 };
  90
  91 static enum drm_connector_status imx_ldb_connector_detect(
  92                 struct drm_connector *connector, bool force)
  93 {
  94         return connector_status_connected;
  95 }
  96
  97 static int imx_ldb_connector_get_modes(struct drm_connector *connector)
  98 {
  99         struct imx_ldb_channel *imx_ldb_ch = con_to_imx_ldb_ch(connector);
 100         int num_modes = 0;
 101
 102         if (imx_ldb_ch->panel && imx_ldb_ch->panel->funcs &&
 103             imx_ldb_ch->panel->funcs->get_modes) {
 104                 struct drm_display_info *di = &connector->display_info;
 105
 106                 num_modes = imx_ldb_ch->panel->funcs->get_modes(imx_ldb_ch->panel);
 107                 if (!imx_ldb_ch->bus_format && di->num_bus_formats)
 108                         imx_ldb_ch->bus_format = di->bus_formats[0];
 109                 if (num_modes > 0)
 110                         return num_modes;
 111         }
 112
 113         if (!imx_ldb_ch->edid && imx_ldb_ch->ddc)
 114                 imx_ldb_ch->edid = drm_get_edid(connector, imx_ldb_ch->ddc);
 115
 116         if (imx_ldb_ch->edid) {
 117                 drm_mode_connector_update_edid_property(connector,
 118                                                         imx_ldb_ch->edid);
 119                 num_modes = drm_add_edid_modes(connector, imx_ldb_ch->edid);
 120         }
 121
 122         if (imx_ldb_ch->mode_valid) {
 123                 struct drm_display_mode *mode;
 124
 125                 mode = drm_mode_create(connector->dev);
 126                 if (!mode)
 127                         return -EINVAL;
 128                 drm_mode_copy(mode, &imx_ldb_ch->mode);
 129                 mode->type |= DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
 130                 drm_mode_probed_add(connector, mode);
 131                 num_modes++;
 132         }
 133
 134         return num_modes;
 135 }
 136
 137 static struct drm_encoder *imx_ldb_connector_best_encoder(
 138                 struct drm_connector *connector)
 139 {
 140         struct imx_ldb_channel *imx_ldb_ch = con_to_imx_ldb_ch(connector);
 141
 142         return &imx_ldb_ch->encoder;
 143 }
 144
 145 static void imx_ldb_encoder_dpms(struct drm_encoder *encoder, int mode)
 146 {
 147 }
 148
 149 static void imx_ldb_set_clock(struct imx_ldb *ldb, int mux, int chno,
 150                 unsigned long serial_clk, unsigned long di_clk)
 151 {
 152         int ret;
 153
 154         dev_dbg(ldb->dev, "%s: now: %ld want: %ld\n", __func__,
 155                         clk_get_rate(ldb->clk_pll[chno]), serial_clk);
 156         clk_set_rate(ldb->clk_pll[chno], serial_clk);
 157
 158         dev_dbg(ldb->dev, "%s after: %ld\n", __func__,
 159                         clk_get_rate(ldb->clk_pll[chno]));
 160
 161         dev_dbg(ldb->dev, "%s: now: %ld want: %ld\n", __func__,
 162                         clk_get_rate(ldb->clk[chno]),
 163                         (long int)di_clk);
 164         clk_set_rate(ldb->clk[chno], di_clk);
 165
 166         dev_dbg(ldb->dev, "%s after: %ld\n", __func__,
 167                         clk_get_rate(ldb->clk[chno]));
 168
 169         /* set display clock mux to LDB input clock */
 170         ret = clk_set_parent(ldb->clk_sel[mux], ldb->clk[chno]);
 171         if (ret)
 172                 dev_err(ldb->dev,
 173                         "unable to set di%d parent clock to ldb_di%d\n", mux,
 174                         chno);
 175 }
 176
 177 static void imx_ldb_encoder_prepare(struct drm_encoder *encoder)
 178 {
 179         struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
 180         struct imx_ldb *ldb = imx_ldb_ch->ldb;
 181         int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
 182         u32 bus_format;
 183
 184         switch (imx_ldb_ch->bus_format) {
 185         default:
 186                 dev_warn(ldb->dev,
 187                          "could not determine data mapping, default to 18-bit \"spwg\"\n");
 188                 /* fallthrough */
 189         case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
 190                 bus_format = MEDIA_BUS_FMT_RGB666_1X18;
 191                 break;
 192         case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
 193                 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
 194                 if (imx_ldb_ch->chno == 0 || dual)
 195                         ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH0_24;
 196                 if (imx_ldb_ch->chno == 1 || dual)
 197                         ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH1_24;
 198                 break;
 199         case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
 200                 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
 201                 if (imx_ldb_ch->chno == 0 || dual)
 202                         ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH0_24 |
 203                                          LDB_BIT_MAP_CH0_JEIDA;
 204                 if (imx_ldb_ch->chno == 1 || dual)
 205                         ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH1_24 |
 206                                          LDB_BIT_MAP_CH1_JEIDA;
 207                 break;
 208         }
 209
 210         imx_drm_set_bus_format(encoder, bus_format);
 211 }
 212
 213 static void imx_ldb_encoder_commit(struct drm_encoder *encoder)
 214 {
 215         struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
 216         struct imx_ldb *ldb = imx_ldb_ch->ldb;
 217         int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
 218         int mux = drm_of_encoder_active_port_id(imx_ldb_ch->child, encoder);
 219
 220         drm_panel_prepare(imx_ldb_ch->panel);
 221
 222         if (dual) {
 223                 clk_prepare_enable(ldb->clk[0]);
 224                 clk_prepare_enable(ldb->clk[1]);
 225         }
 226
 227         if (imx_ldb_ch == &ldb->channel[0] || dual) {
 228                 ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK;
 229                 if (mux == 0 || ldb->lvds_mux)
 230                         ldb->ldb_ctrl |= LDB_CH0_MODE_EN_TO_DI0;
 231                 else if (mux == 1)
 232                         ldb->ldb_ctrl |= LDB_CH0_MODE_EN_TO_DI1;
 233         }
 234         if (imx_ldb_ch == &ldb->channel[1] || dual) {
 235                 ldb->ldb_ctrl &= ~LDB_CH1_MODE_EN_MASK;
 236                 if (mux == 1 || ldb->lvds_mux)
 237                         ldb->ldb_ctrl |= LDB_CH1_MODE_EN_TO_DI1;
 238                 else if (mux == 0)
 239                         ldb->ldb_ctrl |= LDB_CH1_MODE_EN_TO_DI0;
 240         }
 241
 242         if (ldb->lvds_mux) {
 243                 const struct bus_mux *lvds_mux = NULL;
 244
 245                 if (imx_ldb_ch == &ldb->channel[0])
 246                         lvds_mux = &ldb->lvds_mux[0];
 247                 else if (imx_ldb_ch == &ldb->channel[1])
 248                         lvds_mux = &ldb->lvds_mux[1];
 249
 250                 regmap_update_bits(ldb->regmap, lvds_mux->reg, lvds_mux->mask,
 251                                    mux << lvds_mux->shift);
 252         }
 253
 254         regmap_write(ldb->regmap, IOMUXC_GPR2, ldb->ldb_ctrl);
 255
 256         drm_panel_enable(imx_ldb_ch->panel);
 257 }
 258
 259 static void imx_ldb_encoder_mode_set(struct drm_encoder *encoder,
 260                          struct drm_display_mode *orig_mode,
 261                          struct drm_display_mode *mode)
 262 {
 263         struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
 264         struct imx_ldb *ldb = imx_ldb_ch->ldb;
 265         int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
 266         unsigned long serial_clk;
 267         unsigned long di_clk = mode->clock * 1000;
 268         int mux = drm_of_encoder_active_port_id(imx_ldb_ch->child, encoder);
 269
 270         if (mode->clock > 170000) {
 271                 dev_warn(ldb->dev,
 272                          "%s: mode exceeds 170 MHz pixel clock\n", __func__);
 273         }
 274         if (mode->clock > 85000 && !dual) {
 275                 dev_warn(ldb->dev,
 276                          "%s: mode exceeds 85 MHz pixel clock\n", __func__);
 277         }
 278
 279         if (dual) {
 280                 serial_clk = 3500UL * mode->clock;
 281                 imx_ldb_set_clock(ldb, mux, 0, serial_clk, di_clk);
 282                 imx_ldb_set_clock(ldb, mux, 1, serial_clk, di_clk);
 283         } else {
 284                 serial_clk = 7000UL * mode->clock;
 285                 imx_ldb_set_clock(ldb, mux, imx_ldb_ch->chno, serial_clk,
 286                                   di_clk);
 287         }
 288
 289         /* FIXME - assumes straight connections DI0 --> CH0, DI1 --> CH1 */
 290         if (imx_ldb_ch == &ldb->channel[0]) {
 291                 if (mode->flags & DRM_MODE_FLAG_NVSYNC)
 292                         ldb->ldb_ctrl |= LDB_DI0_VS_POL_ACT_LOW;
 293                 else if (mode->flags & DRM_MODE_FLAG_PVSYNC)
 294                         ldb->ldb_ctrl &= ~LDB_DI0_VS_POL_ACT_LOW;
 295         }
 296         if (imx_ldb_ch == &ldb->channel[1]) {
 297                 if (mode->flags & DRM_MODE_FLAG_NVSYNC)
 298                         ldb->ldb_ctrl |= LDB_DI1_VS_POL_ACT_LOW;
 299                 else if (mode->flags & DRM_MODE_FLAG_PVSYNC)
 300                         ldb->ldb_ctrl &= ~LDB_DI1_VS_POL_ACT_LOW;
 301         }
 302 }
 303
 304 static void imx_ldb_encoder_disable(struct drm_encoder *encoder)
 305 {
 306         struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
 307         struct imx_ldb *ldb = imx_ldb_ch->ldb;
 308         int mux, ret;
 309
 310         /*
 311          * imx_ldb_encoder_disable is called by
 312          * drm_helper_disable_unused_functions without
 313          * the encoder being enabled before.
 314          */
 315         if (imx_ldb_ch == &ldb->channel[0] &&
 316             (ldb->ldb_ctrl & LDB_CH0_MODE_EN_MASK) == 0)
 317                 return;
 318         else if (imx_ldb_ch == &ldb->channel[1] &&
 319                  (ldb->ldb_ctrl & LDB_CH1_MODE_EN_MASK) == 0)
 320                 return;
 321
 322         drm_panel_disable(imx_ldb_ch->panel);
 323
 324         if (imx_ldb_ch == &ldb->channel[0])
 325                 ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK;
 326         else if (imx_ldb_ch == &ldb->channel[1])
 327                 ldb->ldb_ctrl &= ~LDB_CH1_MODE_EN_MASK;
 328
 329         regmap_write(ldb->regmap, IOMUXC_GPR2, ldb->ldb_ctrl);
 330
 331         if (ldb->ldb_ctrl & LDB_SPLIT_MODE_EN) {
 332                 clk_disable_unprepare(ldb->clk[0]);
 333                 clk_disable_unprepare(ldb->clk[1]);
 334         }
 335
 336         if (ldb->lvds_mux) {
 337                 const struct bus_mux *lvds_mux = NULL;
 338
 339                 if (imx_ldb_ch == &ldb->channel[0])
 340                         lvds_mux = &ldb->lvds_mux[0];
 341                 else if (imx_ldb_ch == &ldb->channel[1])
 342                         lvds_mux = &ldb->lvds_mux[1];
 343
 344                 regmap_read(ldb->regmap, lvds_mux->reg, &mux);
 345                 mux &= lvds_mux->mask;
 346                 mux >>= lvds_mux->shift;
 347         } else {
 348                 mux = (imx_ldb_ch == &ldb->channel[0]) ? 0 : 1;
 349         }
 350
 351         /* set display clock mux back to original input clock */
 352         ret = clk_set_parent(ldb->clk_sel[mux], ldb->clk_parent[mux]);
 353         if (ret)
 354                 dev_err(ldb->dev,
 355                         "unable to set di%d parent clock to original parent\n",
 356                         mux);
 357
 358         drm_panel_unprepare(imx_ldb_ch->panel);
 359 }
 360
 361 static const struct drm_connector_funcs imx_ldb_connector_funcs = {
 362         .dpms = drm_helper_connector_dpms,
 363         .fill_modes = drm_helper_probe_single_connector_modes,
 364         .detect = imx_ldb_connector_detect,
 365         .destroy = imx_drm_connector_destroy,
 366         .reset = drm_atomic_helper_connector_reset,
 367         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 368         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 369 };
 370
 371 static const struct drm_connector_helper_funcs imx_ldb_connector_helper_funcs = {
 372         .get_modes = imx_ldb_connector_get_modes,
 373         .best_encoder = imx_ldb_connector_best_encoder,
 374 };
 375
 376 static const struct drm_encoder_funcs imx_ldb_encoder_funcs = {
 377         .destroy = imx_drm_encoder_destroy,
 378 };
 379
 380 static const struct drm_encoder_helper_funcs imx_ldb_encoder_helper_funcs = {
 381         .dpms = imx_ldb_encoder_dpms,
 382         .prepare = imx_ldb_encoder_prepare,
 383         .commit = imx_ldb_encoder_commit,
 384         .mode_set = imx_ldb_encoder_mode_set,
 385         .disable = imx_ldb_encoder_disable,
 386 };
 387
 388 static int imx_ldb_get_clk(struct imx_ldb *ldb, int chno)
 389 {
 390         char clkname[16];
 391
 392         snprintf(clkname, sizeof(clkname), "di%d", chno);
 393         ldb->clk[chno] = devm_clk_get(ldb->dev, clkname);
 394         if (IS_ERR(ldb->clk[chno]))
 395                 return PTR_ERR(ldb->clk[chno]);
 396
 397         snprintf(clkname, sizeof(clkname), "di%d_pll", chno);
 398         ldb->clk_pll[chno] = devm_clk_get(ldb->dev, clkname);
 399
 400         return PTR_ERR_OR_ZERO(ldb->clk_pll[chno]);
 401 }
 402
 403 static int imx_ldb_register(struct drm_device *drm,
 404         struct imx_ldb_channel *imx_ldb_ch)
 405 {
 406         struct imx_ldb *ldb = imx_ldb_ch->ldb;
 407         int ret;
 408
 409         ret = imx_drm_encoder_parse_of(drm, &imx_ldb_ch->encoder,
 410                                        imx_ldb_ch->child);
 411         if (ret)
 412                 return ret;
 413
 414         ret = imx_ldb_get_clk(ldb, imx_ldb_ch->chno);
 415         if (ret)
 416                 return ret;
 417
 418         if (ldb->ldb_ctrl & LDB_SPLIT_MODE_EN) {
 419                 ret = imx_ldb_get_clk(ldb, 1);
 420                 if (ret)
 421                         return ret;
 422         }
 423
 424         drm_encoder_helper_add(&imx_ldb_ch->encoder,
 425                         &imx_ldb_encoder_helper_funcs);
 426         drm_encoder_init(drm, &imx_ldb_ch->encoder, &imx_ldb_encoder_funcs,
 427                          DRM_MODE_ENCODER_LVDS, NULL);
 428
 429         drm_connector_helper_add(&imx_ldb_ch->connector,
 430                         &imx_ldb_connector_helper_funcs);
 431         drm_connector_init(drm, &imx_ldb_ch->connector,
 432                            &imx_ldb_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
 433
 434         if (imx_ldb_ch->panel)
 435                 drm_panel_attach(imx_ldb_ch->panel, &imx_ldb_ch->connector);
 436
 437         drm_mode_connector_attach_encoder(&imx_ldb_ch->connector,
 438                         &imx_ldb_ch->encoder);
 439
 440         return 0;
 441 }
 442
 443 enum {
 444         LVDS_BIT_MAP_SPWG,
 445         LVDS_BIT_MAP_JEIDA
 446 };
 447
 448 struct imx_ldb_bit_mapping {
 449         u32 bus_format;
 450         u32 datawidth;
 451         const char * const mapping;
 452 };
 453
 454 static const struct imx_ldb_bit_mapping imx_ldb_bit_mappings[] = {
 455         { MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,  18, "spwg" },
 456         { MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,  24, "spwg" },
 457         { MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA, 24, "jeida" },
 458 };
 459
 460 static u32 of_get_bus_format(struct device *dev, struct device_node *np)
 461 {
 462         const char *bm;
 463         u32 datawidth = 0;
 464         int ret, i;
 465
 466         ret = of_property_read_string(np, "fsl,data-mapping", &bm);
 467         if (ret < 0)
 468                 return ret;
 469
 470         of_property_read_u32(np, "fsl,data-width", &datawidth);
 471
 472         for (i = 0; i < ARRAY_SIZE(imx_ldb_bit_mappings); i++) {
 473                 if (!strcasecmp(bm, imx_ldb_bit_mappings[i].mapping) &&
 474                     datawidth == imx_ldb_bit_mappings[i].datawidth)
 475                         return imx_ldb_bit_mappings[i].bus_format;
 476         }
 477
 478         dev_err(dev, "invalid data mapping: %d-bit \"%s\"\n", datawidth, bm);
 479
 480         return -ENOENT;
 481 }
 482
 483 static struct bus_mux imx6q_lvds_mux[2] = {
 484         {
 485                 .reg = IOMUXC_GPR3,
 486                 .shift = 6,
 487                 .mask = IMX6Q_GPR3_LVDS0_MUX_CTL_MASK,
 488         }, {
 489                 .reg = IOMUXC_GPR3,
 490                 .shift = 8,
 491                 .mask = IMX6Q_GPR3_LVDS1_MUX_CTL_MASK,
 492         }
 493 };
 494
 495 /*
 496  * For a device declaring compatible = "fsl,imx6q-ldb", "fsl,imx53-ldb",
 497  * of_match_device will walk through this list and take the first entry
 498  * matching any of its compatible values. Therefore, the more generic
 499  * entries (in this case fsl,imx53-ldb) need to be ordered last.
 500  */
 501 static const struct of_device_id imx_ldb_dt_ids[] = {
 502         { .compatible = "fsl,imx6q-ldb", .data = imx6q_lvds_mux, },
 503         { .compatible = "fsl,imx53-ldb", .data = NULL, },
 504         { }
 505 };
 506 MODULE_DEVICE_TABLE(of, imx_ldb_dt_ids);
 507
 508 static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
 509 {
 510         struct drm_device *drm = data;
 511         struct device_node *np = dev->of_node;
 512         const struct of_device_id *of_id =
 513                         of_match_device(imx_ldb_dt_ids, dev);
 514         struct device_node *child;
 515         const u8 *edidp;
 516         struct imx_ldb *imx_ldb;
 517         int dual;
 518         int ret;
 519         int i;
 520
 521         imx_ldb = devm_kzalloc(dev, sizeof(*imx_ldb), GFP_KERNEL);
 522         if (!imx_ldb)
 523                 return -ENOMEM;
 524
 525         imx_ldb->regmap = syscon_regmap_lookup_by_phandle(np, "gpr");
 526         if (IS_ERR(imx_ldb->regmap)) {
 527                 dev_err(dev, "failed to get parent regmap\n");
 528                 return PTR_ERR(imx_ldb->regmap);
 529         }
 530
 531         imx_ldb->dev = dev;
 532
 533         if (of_id)
 534                 imx_ldb->lvds_mux = of_id->data;
 535
 536         dual = of_property_read_bool(np, "fsl,dual-channel");
 537         if (dual)
 538                 imx_ldb->ldb_ctrl |= LDB_SPLIT_MODE_EN;
 539
 540         /*
 541          * There are three different possible clock mux configurations:
 542          * i.MX53:  ipu1_di0_sel, ipu1_di1_sel
 543          * i.MX6q:  ipu1_di0_sel, ipu1_di1_sel, ipu2_di0_sel, ipu2_di1_sel
 544          * i.MX6dl: ipu1_di0_sel, ipu1_di1_sel, lcdif_sel
 545          * Map them all to di0_sel...di3_sel.
 546          */
 547         for (i = 0; i < 4; i++) {
 548                 char clkname[16];
 549
 550                 sprintf(clkname, "di%d_sel", i);
 551                 imx_ldb->clk_sel[i] = devm_clk_get(imx_ldb->dev, clkname);
 552                 if (IS_ERR(imx_ldb->clk_sel[i])) {
 553                         ret = PTR_ERR(imx_ldb->clk_sel[i]);
 554                         imx_ldb->clk_sel[i] = NULL;
 555                         break;
 556                 }
 557
 558                 imx_ldb->clk_parent[i] = clk_get_parent(imx_ldb->clk_sel[i]);
 559         }
 560         if (i == 0)
 561                 return ret;
 562
 563         for_each_child_of_node(np, child) {
 564                 struct imx_ldb_channel *channel;
 565                 struct device_node *ddc_node;
 566                 struct device_node *ep;
 567
 568                 ret = of_property_read_u32(child, "reg", &i);
 569                 if (ret || i < 0 || i > 1)
 570                         return -EINVAL;
 571
 572                 if (dual && i > 0) {
 573                         dev_warn(dev, "dual-channel mode, ignoring second output\n");
 574                         continue;
 575                 }
 576
 577                 if (!of_device_is_available(child))
 578                         continue;
 579
 580                 channel = &imx_ldb->channel[i];
 581                 channel->ldb = imx_ldb;
 582                 channel->chno = i;
 583                 channel->child = child;
 584
 585                 /*
 586                  * The output port is port@4 with an external 4-port mux or
 587                  * port@2 with the internal 2-port mux.
 588                  */
 589                 ep = of_graph_get_endpoint_by_regs(child,
 590                                                    imx_ldb->lvds_mux ? 4 : 2,
 591                                                    -1);
 592                 if (ep) {
 593                         struct device_node *remote;
 594
 595                         remote = of_graph_get_remote_port_parent(ep);
 596                         of_node_put(ep);
 597                         if (remote)
 598                                 channel->panel = of_drm_find_panel(remote);
 599                         else
 600                                 return -EPROBE_DEFER;
 601                         of_node_put(remote);
 602                         if (!channel->panel) {
 603                                 dev_err(dev, "panel not found: %s\n",
 604                                         remote->full_name);
 605                                 return -EPROBE_DEFER;
 606                         }
 607                 }
 608
 609                 ddc_node = of_parse_phandle(child, "ddc-i2c-bus", 0);
 610                 if (ddc_node) {
 611                         channel->ddc = of_find_i2c_adapter_by_node(ddc_node);
 612                         of_node_put(ddc_node);
 613                         if (!channel->ddc) {
 614                                 dev_warn(dev, "failed to get ddc i2c adapter\n");
 615                                 return -EPROBE_DEFER;
 616                         }
 617                 }
 618
 619                 if (!channel->ddc) {
 620                         /* if no DDC available, fallback to hardcoded EDID */
 621                         dev_dbg(dev, "no ddc available\n");
 622
 623                         edidp = of_get_property(child, "edid",
 624                                                 &channel->edid_len);
 625                         if (edidp) {
 626                                 channel->edid = kmemdup(edidp,
 627                                                         channel->edid_len,
 628                                                         GFP_KERNEL);
 629                         } else if (!channel->panel) {
 630                                 /* fallback to display-timings node */
 631                                 ret = of_get_drm_display_mode(child,
 632                                                               &channel->mode,
 633                                                               OF_USE_NATIVE_MODE);
 634                                 if (!ret)
 635                                         channel->mode_valid = 1;
 636                         }
 637                 }
 638
 639                 channel->bus_format = of_get_bus_format(dev, child);
 640                 if (channel->bus_format == -EINVAL) {
 641                         /*
 642                          * If no bus format was specified in the device tree,
 643                          * we can still get it from the connected panel later.
 644                          */
 645                         if (channel->panel && channel->panel->funcs &&
 646                             channel->panel->funcs->get_modes)
 647                                 channel->bus_format = 0;
 648                 }
 649                 if (channel->bus_format < 0) {
 650                         dev_err(dev, "could not determine data mapping: %d\n",
 651                                 channel->bus_format);
 652                         return channel->bus_format;
 653                 }
 654
 655                 ret = imx_ldb_register(drm, channel);
 656                 if (ret)
 657                         return ret;
 658         }
 659
 660         dev_set_drvdata(dev, imx_ldb);
 661
 662         return 0;
 663 }
 664
 665 static void imx_ldb_unbind(struct device *dev, struct device *master,
 666         void *data)
 667 {
 668         struct imx_ldb *imx_ldb = dev_get_drvdata(dev);
 669         int i;
 670
 671         for (i = 0; i < 2; i++) {
 672                 struct imx_ldb_channel *channel = &imx_ldb->channel[i];
 673
 674                 if (!channel->connector.funcs)
 675                         continue;
 676
 677                 channel->connector.funcs->destroy(&channel->connector);
 678                 channel->encoder.funcs->destroy(&channel->encoder);
 679
 680                 kfree(channel->edid);
 681                 i2c_put_adapter(channel->ddc);
 682         }
 683 }
 684
 685 static const struct component_ops imx_ldb_ops = {
 686         .bind   = imx_ldb_bind,
 687         .unbind = imx_ldb_unbind,
 688 };
 689
 690 static int imx_ldb_probe(struct platform_device *pdev)
 691 {
 692         return component_add(&pdev->dev, &imx_ldb_ops);
 693 }
 694
 695 static int imx_ldb_remove(struct platform_device *pdev)
 696 {
 697         component_del(&pdev->dev, &imx_ldb_ops);
 698         return 0;
 699 }
 700
 701 static struct platform_driver imx_ldb_driver = {
 702         .probe          = imx_ldb_probe,
 703         .remove         = imx_ldb_remove,
 704         .driver         = {
 705                 .of_match_table = imx_ldb_dt_ids,
 706                 .name   = DRIVER_NAME,
 707         },
 708 };
 709
 710 module_platform_driver(imx_ldb_driver);
 711
 712 MODULE_DESCRIPTION("i.MX LVDS driver");
 713 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
 714 MODULE_LICENSE("GPL");
 715 MODULE_ALIAS("platform:" DRIVER_NAME);