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