drivers/staging/imx-drm/imx-drm-core.c

   1 /*
   2  * Freescale i.MX drm driver
   3  *
   4  * Copyright (C) 2011 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/component.h>
  17 #include <linux/device.h>
  18 #include <linux/fb.h>
  19 #include <linux/module.h>
  20 #include <linux/of_graph.h>
  21 #include <linux/platform_device.h>
  22 #include <drm/drmP.h>
  23 #include <drm/drm_fb_helper.h>
  24 #include <drm/drm_crtc_helper.h>
  25 #include <drm/drm_gem_cma_helper.h>
  26 #include <drm/drm_fb_cma_helper.h>
  27
  28 #include "imx-drm.h"
  29
  30 #define MAX_CRTC        4
  31
  32 struct imx_drm_crtc;
  33
  34 struct imx_drm_component {
  35         struct device_node *of_node;
  36         struct list_head list;
  37 };
  38
  39 struct imx_drm_device {
  40         struct drm_device                       *drm;
  41         struct imx_drm_crtc                     *crtc[MAX_CRTC];
  42         int                                     pipes;
  43         struct drm_fbdev_cma                    *fbhelper;
  44 };
  45
  46 struct imx_drm_crtc {
  47         struct drm_crtc                         *crtc;
  48         int                                     pipe;
  49         struct imx_drm_crtc_helper_funcs        imx_drm_helper_funcs;
  50         struct device_node                      *port;
  51 };
  52
  53 static int legacyfb_depth = 16;
  54 module_param(legacyfb_depth, int, 0444);
  55
  56 int imx_drm_crtc_id(struct imx_drm_crtc *crtc)
  57 {
  58         return crtc->pipe;
  59 }
  60 EXPORT_SYMBOL_GPL(imx_drm_crtc_id);
  61
  62 static void imx_drm_driver_lastclose(struct drm_device *drm)
  63 {
  64 #if IS_ENABLED(CONFIG_DRM_IMX_FB_HELPER)
  65         struct imx_drm_device *imxdrm = drm->dev_private;
  66
  67         if (imxdrm->fbhelper)
  68                 drm_fbdev_cma_restore_mode(imxdrm->fbhelper);
  69 #endif
  70 }
  71
  72 static int imx_drm_driver_unload(struct drm_device *drm)
  73 {
  74 #if IS_ENABLED(CONFIG_DRM_IMX_FB_HELPER)
  75         struct imx_drm_device *imxdrm = drm->dev_private;
  76 #endif
  77
  78         drm_kms_helper_poll_fini(drm);
  79
  80 #if IS_ENABLED(CONFIG_DRM_IMX_FB_HELPER)
  81         if (imxdrm->fbhelper)
  82                 drm_fbdev_cma_fini(imxdrm->fbhelper);
  83 #endif
  84
  85         component_unbind_all(drm->dev, drm);
  86
  87         drm_vblank_cleanup(drm);
  88         drm_mode_config_cleanup(drm);
  89
  90         return 0;
  91 }
  92
  93 static struct imx_drm_crtc *imx_drm_find_crtc(struct drm_crtc *crtc)
  94 {
  95         struct imx_drm_device *imxdrm = crtc->dev->dev_private;
  96         unsigned i;
  97
  98         for (i = 0; i < MAX_CRTC; i++)
  99                 if (imxdrm->crtc[i] && imxdrm->crtc[i]->crtc == crtc)
 100                         return imxdrm->crtc[i];
 101
 102         return NULL;
 103 }
 104
 105 int imx_drm_panel_format_pins(struct drm_encoder *encoder,
 106                 u32 interface_pix_fmt, int hsync_pin, int vsync_pin)
 107 {
 108         struct imx_drm_crtc_helper_funcs *helper;
 109         struct imx_drm_crtc *imx_crtc;
 110
 111         imx_crtc = imx_drm_find_crtc(encoder->crtc);
 112         if (!imx_crtc)
 113                 return -EINVAL;
 114
 115         helper = &imx_crtc->imx_drm_helper_funcs;
 116         if (helper->set_interface_pix_fmt)
 117                 return helper->set_interface_pix_fmt(encoder->crtc,
 118                                 encoder->encoder_type, interface_pix_fmt,
 119                                 hsync_pin, vsync_pin);
 120         return 0;
 121 }
 122 EXPORT_SYMBOL_GPL(imx_drm_panel_format_pins);
 123
 124 int imx_drm_panel_format(struct drm_encoder *encoder, u32 interface_pix_fmt)
 125 {
 126         return imx_drm_panel_format_pins(encoder, interface_pix_fmt, 2, 3);
 127 }
 128 EXPORT_SYMBOL_GPL(imx_drm_panel_format);
 129
 130 int imx_drm_crtc_vblank_get(struct imx_drm_crtc *imx_drm_crtc)
 131 {
 132         return drm_vblank_get(imx_drm_crtc->crtc->dev, imx_drm_crtc->pipe);
 133 }
 134 EXPORT_SYMBOL_GPL(imx_drm_crtc_vblank_get);
 135
 136 void imx_drm_crtc_vblank_put(struct imx_drm_crtc *imx_drm_crtc)
 137 {
 138         drm_vblank_put(imx_drm_crtc->crtc->dev, imx_drm_crtc->pipe);
 139 }
 140 EXPORT_SYMBOL_GPL(imx_drm_crtc_vblank_put);
 141
 142 void imx_drm_handle_vblank(struct imx_drm_crtc *imx_drm_crtc)
 143 {
 144         drm_handle_vblank(imx_drm_crtc->crtc->dev, imx_drm_crtc->pipe);
 145 }
 146 EXPORT_SYMBOL_GPL(imx_drm_handle_vblank);
 147
 148 static int imx_drm_enable_vblank(struct drm_device *drm, int crtc)
 149 {
 150         struct imx_drm_device *imxdrm = drm->dev_private;
 151         struct imx_drm_crtc *imx_drm_crtc = imxdrm->crtc[crtc];
 152         int ret;
 153
 154         if (!imx_drm_crtc)
 155                 return -EINVAL;
 156
 157         if (!imx_drm_crtc->imx_drm_helper_funcs.enable_vblank)
 158                 return -ENOSYS;
 159
 160         ret = imx_drm_crtc->imx_drm_helper_funcs.enable_vblank(
 161                         imx_drm_crtc->crtc);
 162
 163         return ret;
 164 }
 165
 166 static void imx_drm_disable_vblank(struct drm_device *drm, int crtc)
 167 {
 168         struct imx_drm_device *imxdrm = drm->dev_private;
 169         struct imx_drm_crtc *imx_drm_crtc = imxdrm->crtc[crtc];
 170
 171         if (!imx_drm_crtc)
 172                 return;
 173
 174         if (!imx_drm_crtc->imx_drm_helper_funcs.disable_vblank)
 175                 return;
 176
 177         imx_drm_crtc->imx_drm_helper_funcs.disable_vblank(imx_drm_crtc->crtc);
 178 }
 179
 180 static void imx_drm_driver_preclose(struct drm_device *drm,
 181                 struct drm_file *file)
 182 {
 183         int i;
 184
 185         if (!file->is_master)
 186                 return;
 187
 188         for (i = 0; i < MAX_CRTC; i++)
 189                 imx_drm_disable_vblank(drm, i);
 190 }
 191
 192 static const struct file_operations imx_drm_driver_fops = {
 193         .owner = THIS_MODULE,
 194         .open = drm_open,
 195         .release = drm_release,
 196         .unlocked_ioctl = drm_ioctl,
 197         .mmap = drm_gem_cma_mmap,
 198         .poll = drm_poll,
 199         .read = drm_read,
 200         .llseek = noop_llseek,
 201 };
 202
 203 void imx_drm_connector_destroy(struct drm_connector *connector)
 204 {
 205         drm_sysfs_connector_remove(connector);
 206         drm_connector_cleanup(connector);
 207 }
 208 EXPORT_SYMBOL_GPL(imx_drm_connector_destroy);
 209
 210 void imx_drm_encoder_destroy(struct drm_encoder *encoder)
 211 {
 212         drm_encoder_cleanup(encoder);
 213 }
 214 EXPORT_SYMBOL_GPL(imx_drm_encoder_destroy);
 215
 216 static void imx_drm_output_poll_changed(struct drm_device *drm)
 217 {
 218 #if IS_ENABLED(CONFIG_DRM_IMX_FB_HELPER)
 219         struct imx_drm_device *imxdrm = drm->dev_private;
 220
 221         drm_fbdev_cma_hotplug_event(imxdrm->fbhelper);
 222 #endif
 223 }
 224
 225 static struct drm_mode_config_funcs imx_drm_mode_config_funcs = {
 226         .fb_create = drm_fb_cma_create,
 227         .output_poll_changed = imx_drm_output_poll_changed,
 228 };
 229
 230 /*
 231  * Main DRM initialisation. This binds, initialises and registers
 232  * with DRM the subcomponents of the driver.
 233  */
 234 static int imx_drm_driver_load(struct drm_device *drm, unsigned long flags)
 235 {
 236         struct imx_drm_device *imxdrm;
 237         struct drm_connector *connector;
 238         int ret;
 239
 240         imxdrm = devm_kzalloc(drm->dev, sizeof(*imxdrm), GFP_KERNEL);
 241         if (!imxdrm)
 242                 return -ENOMEM;
 243
 244         imxdrm->drm = drm;
 245
 246         drm->dev_private = imxdrm;
 247
 248         /*
 249          * enable drm irq mode.
 250          * - with irq_enabled = true, we can use the vblank feature.
 251          *
 252          * P.S. note that we wouldn't use drm irq handler but
 253          *      just specific driver own one instead because
 254          *      drm framework supports only one irq handler and
 255          *      drivers can well take care of their interrupts
 256          */
 257         drm->irq_enabled = true;
 258
 259         /*
 260          * set max width and height as default value(4096x4096).
 261          * this value would be used to check framebuffer size limitation
 262          * at drm_mode_addfb().
 263          */
 264         drm->mode_config.min_width = 64;
 265         drm->mode_config.min_height = 64;
 266         drm->mode_config.max_width = 4096;
 267         drm->mode_config.max_height = 4096;
 268         drm->mode_config.funcs = &imx_drm_mode_config_funcs;
 269
 270         drm_mode_config_init(drm);
 271
 272         ret = drm_vblank_init(drm, MAX_CRTC);
 273         if (ret)
 274                 goto err_kms;
 275
 276         /*
 277          * with vblank_disable_allowed = true, vblank interrupt will be
 278          * disabled by drm timer once a current process gives up ownership
 279          * of vblank event. (after drm_vblank_put function is called)
 280          */
 281         drm->vblank_disable_allowed = true;
 282
 283         platform_set_drvdata(drm->platformdev, drm);
 284
 285         /* Now try and bind all our sub-components */
 286         ret = component_bind_all(drm->dev, drm);
 287         if (ret)
 288                 goto err_vblank;
 289
 290         /*
 291          * All components are now added, we can publish the connector sysfs
 292          * entries to userspace.  This will generate hotplug events and so
 293          * userspace will expect to be able to access DRM at this point.
 294          */
 295         list_for_each_entry(connector, &drm->mode_config.connector_list, head) {
 296                 ret = drm_sysfs_connector_add(connector);
 297                 if (ret) {
 298                         dev_err(drm->dev,
 299                                 "[CONNECTOR:%d:%s] drm_sysfs_connector_add failed: %d\n",
 300                                 connector->base.id,
 301                                 connector->name, ret);
 302                         goto err_unbind;
 303                 }
 304         }
 305
 306         /*
 307          * All components are now initialised, so setup the fb helper.
 308          * The fb helper takes copies of key hardware information, so the
 309          * crtcs/connectors/encoders must not change after this point.
 310          */
 311 #if IS_ENABLED(CONFIG_DRM_IMX_FB_HELPER)
 312         if (legacyfb_depth != 16 && legacyfb_depth != 32) {
 313                 dev_warn(drm->dev, "Invalid legacyfb_depth.  Defaulting to 16bpp\n");
 314                 legacyfb_depth = 16;
 315         }
 316         imxdrm->fbhelper = drm_fbdev_cma_init(drm, legacyfb_depth,
 317                                 drm->mode_config.num_crtc, MAX_CRTC);
 318         if (IS_ERR(imxdrm->fbhelper)) {
 319                 ret = PTR_ERR(imxdrm->fbhelper);
 320                 imxdrm->fbhelper = NULL;
 321                 goto err_unbind;
 322         }
 323 #endif
 324
 325         drm_kms_helper_poll_init(drm);
 326
 327         return 0;
 328
 329 err_unbind:
 330         component_unbind_all(drm->dev, drm);
 331 err_vblank:
 332         drm_vblank_cleanup(drm);
 333 err_kms:
 334         drm_mode_config_cleanup(drm);
 335
 336         return ret;
 337 }
 338
 339 /*
 340  * imx_drm_add_crtc - add a new crtc
 341  */
 342 int imx_drm_add_crtc(struct drm_device *drm, struct drm_crtc *crtc,
 343                 struct imx_drm_crtc **new_crtc,
 344                 const struct imx_drm_crtc_helper_funcs *imx_drm_helper_funcs,
 345                 struct device_node *port)
 346 {
 347         struct imx_drm_device *imxdrm = drm->dev_private;
 348         struct imx_drm_crtc *imx_drm_crtc;
 349         int ret;
 350
 351         /*
 352          * The vblank arrays are dimensioned by MAX_CRTC - we can't
 353          * pass IDs greater than this to those functions.
 354          */
 355         if (imxdrm->pipes >= MAX_CRTC)
 356                 return -EINVAL;
 357
 358         if (imxdrm->drm->open_count)
 359                 return -EBUSY;
 360
 361         imx_drm_crtc = kzalloc(sizeof(*imx_drm_crtc), GFP_KERNEL);
 362         if (!imx_drm_crtc)
 363                 return -ENOMEM;
 364
 365         imx_drm_crtc->imx_drm_helper_funcs = *imx_drm_helper_funcs;
 366         imx_drm_crtc->pipe = imxdrm->pipes++;
 367         imx_drm_crtc->port = port;
 368         imx_drm_crtc->crtc = crtc;
 369
 370         imxdrm->crtc[imx_drm_crtc->pipe] = imx_drm_crtc;
 371
 372         *new_crtc = imx_drm_crtc;
 373
 374         ret = drm_mode_crtc_set_gamma_size(imx_drm_crtc->crtc, 256);
 375         if (ret)
 376                 goto err_register;
 377
 378         drm_crtc_helper_add(crtc,
 379                         imx_drm_crtc->imx_drm_helper_funcs.crtc_helper_funcs);
 380
 381         drm_crtc_init(drm, crtc,
 382                         imx_drm_crtc->imx_drm_helper_funcs.crtc_funcs);
 383
 384         return 0;
 385
 386 err_register:
 387         imxdrm->crtc[imx_drm_crtc->pipe] = NULL;
 388         kfree(imx_drm_crtc);
 389         return ret;
 390 }
 391 EXPORT_SYMBOL_GPL(imx_drm_add_crtc);
 392
 393 /*
 394  * imx_drm_remove_crtc - remove a crtc
 395  */
 396 int imx_drm_remove_crtc(struct imx_drm_crtc *imx_drm_crtc)
 397 {
 398         struct imx_drm_device *imxdrm = imx_drm_crtc->crtc->dev->dev_private;
 399
 400         drm_crtc_cleanup(imx_drm_crtc->crtc);
 401
 402         imxdrm->crtc[imx_drm_crtc->pipe] = NULL;
 403
 404         kfree(imx_drm_crtc);
 405
 406         return 0;
 407 }
 408 EXPORT_SYMBOL_GPL(imx_drm_remove_crtc);
 409
 410 /*
 411  * Find the DRM CRTC possible mask for the connected endpoint.
 412  *
 413  * The encoder possible masks are defined by their position in the
 414  * mode_config crtc_list.  This means that CRTCs must not be added
 415  * or removed once the DRM device has been fully initialised.
 416  */
 417 static uint32_t imx_drm_find_crtc_mask(struct imx_drm_device *imxdrm,
 418         struct device_node *endpoint)
 419 {
 420         struct device_node *port;
 421         unsigned i;
 422
 423         port = of_graph_get_remote_port(endpoint);
 424         if (!port)
 425                 return 0;
 426         of_node_put(port);
 427
 428         for (i = 0; i < MAX_CRTC; i++) {
 429                 struct imx_drm_crtc *imx_drm_crtc = imxdrm->crtc[i];
 430                 if (imx_drm_crtc && imx_drm_crtc->port == port)
 431                         return drm_crtc_mask(imx_drm_crtc->crtc);
 432         }
 433
 434         return 0;
 435 }
 436
 437 static struct device_node *imx_drm_of_get_next_endpoint(
 438                 const struct device_node *parent, struct device_node *prev)
 439 {
 440         struct device_node *node = of_graph_get_next_endpoint(parent, prev);
 441         of_node_put(prev);
 442         return node;
 443 }
 444
 445 int imx_drm_encoder_parse_of(struct drm_device *drm,
 446         struct drm_encoder *encoder, struct device_node *np)
 447 {
 448         struct imx_drm_device *imxdrm = drm->dev_private;
 449         struct device_node *ep = NULL;
 450         uint32_t crtc_mask = 0;
 451         int i;
 452
 453         for (i = 0; ; i++) {
 454                 u32 mask;
 455
 456                 ep = imx_drm_of_get_next_endpoint(np, ep);
 457                 if (!ep)
 458                         break;
 459
 460                 mask = imx_drm_find_crtc_mask(imxdrm, ep);
 461
 462                 /*
 463                  * If we failed to find the CRTC(s) which this encoder is
 464                  * supposed to be connected to, it's because the CRTC has
 465                  * not been registered yet.  Defer probing, and hope that
 466                  * the required CRTC is added later.
 467                  */
 468                 if (mask == 0)
 469                         return -EPROBE_DEFER;
 470
 471                 crtc_mask |= mask;
 472         }
 473
 474         if (ep)
 475                 of_node_put(ep);
 476         if (i == 0)
 477                 return -ENOENT;
 478
 479         encoder->possible_crtcs = crtc_mask;
 480
 481         /* FIXME: this is the mask of outputs which can clone this output. */
 482         encoder->possible_clones = ~0;
 483
 484         return 0;
 485 }
 486 EXPORT_SYMBOL_GPL(imx_drm_encoder_parse_of);
 487
 488 /*
 489  * @node: device tree node containing encoder input ports
 490  * @encoder: drm_encoder
 491  */
 492 int imx_drm_encoder_get_mux_id(struct device_node *node,
 493                                struct drm_encoder *encoder)
 494 {
 495         struct imx_drm_crtc *imx_crtc = imx_drm_find_crtc(encoder->crtc);
 496         struct device_node *ep = NULL;
 497         struct of_endpoint endpoint;
 498         struct device_node *port;
 499         int ret;
 500
 501         if (!node || !imx_crtc)
 502                 return -EINVAL;
 503
 504         do {
 505                 ep = imx_drm_of_get_next_endpoint(node, ep);
 506                 if (!ep)
 507                         break;
 508
 509                 port = of_graph_get_remote_port(ep);
 510                 of_node_put(port);
 511                 if (port == imx_crtc->port) {
 512                         ret = of_graph_parse_endpoint(ep, &endpoint);
 513                         return ret ? ret : endpoint.port;
 514                 }
 515         } while (ep);
 516
 517         return -EINVAL;
 518 }
 519 EXPORT_SYMBOL_GPL(imx_drm_encoder_get_mux_id);
 520
 521 static const struct drm_ioctl_desc imx_drm_ioctls[] = {
 522         /* none so far */
 523 };
 524
 525 static struct drm_driver imx_drm_driver = {
 526         .driver_features        = DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME,
 527         .load                   = imx_drm_driver_load,
 528         .unload                 = imx_drm_driver_unload,
 529         .lastclose              = imx_drm_driver_lastclose,
 530         .preclose               = imx_drm_driver_preclose,
 531         .gem_free_object        = drm_gem_cma_free_object,
 532         .gem_vm_ops             = &drm_gem_cma_vm_ops,
 533         .dumb_create            = drm_gem_cma_dumb_create,
 534         .dumb_map_offset        = drm_gem_cma_dumb_map_offset,
 535         .dumb_destroy           = drm_gem_dumb_destroy,
 536
 537         .prime_handle_to_fd     = drm_gem_prime_handle_to_fd,
 538         .prime_fd_to_handle     = drm_gem_prime_fd_to_handle,
 539         .gem_prime_import       = drm_gem_prime_import,
 540         .gem_prime_export       = drm_gem_prime_export,
 541         .gem_prime_get_sg_table = drm_gem_cma_prime_get_sg_table,
 542         .gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
 543         .gem_prime_vmap         = drm_gem_cma_prime_vmap,
 544         .gem_prime_vunmap       = drm_gem_cma_prime_vunmap,
 545         .gem_prime_mmap         = drm_gem_cma_prime_mmap,
 546         .get_vblank_counter     = drm_vblank_count,
 547         .enable_vblank          = imx_drm_enable_vblank,
 548         .disable_vblank         = imx_drm_disable_vblank,
 549         .ioctls                 = imx_drm_ioctls,
 550         .num_ioctls             = ARRAY_SIZE(imx_drm_ioctls),
 551         .fops                   = &imx_drm_driver_fops,
 552         .name                   = "imx-drm",
 553         .desc                   = "i.MX DRM graphics",
 554         .date                   = "20120507",
 555         .major                  = 1,
 556         .minor                  = 0,
 557         .patchlevel             = 0,
 558 };
 559
 560 static int compare_of(struct device *dev, void *data)
 561 {
 562         struct device_node *np = data;
 563
 564         /* Special case for LDB, one device for two channels */
 565         if (of_node_cmp(np->name, "lvds-channel") == 0) {
 566                 np = of_get_parent(np);
 567                 of_node_put(np);
 568         }
 569
 570         return dev->of_node == np;
 571 }
 572
 573 static LIST_HEAD(imx_drm_components);
 574
 575 static int imx_drm_add_components(struct device *master, struct master *m)
 576 {
 577         struct imx_drm_component *component;
 578         int ret;
 579
 580         list_for_each_entry(component, &imx_drm_components, list) {
 581                 ret = component_master_add_child(m, compare_of,
 582                                                  component->of_node);
 583                 if (ret)
 584                         return ret;
 585         }
 586         return 0;
 587 }
 588
 589 static int imx_drm_bind(struct device *dev)
 590 {
 591         return drm_platform_init(&imx_drm_driver, to_platform_device(dev));
 592 }
 593
 594 static void imx_drm_unbind(struct device *dev)
 595 {
 596         drm_put_dev(dev_get_drvdata(dev));
 597 }
 598
 599 static const struct component_master_ops imx_drm_ops = {
 600         .add_components = imx_drm_add_components,
 601         .bind = imx_drm_bind,
 602         .unbind = imx_drm_unbind,
 603 };
 604
 605 static struct imx_drm_component *imx_drm_find_component(struct device *dev,
 606                 struct device_node *node)
 607 {
 608         struct imx_drm_component *component;
 609
 610         list_for_each_entry(component, &imx_drm_components, list)
 611                 if (component->of_node == node)
 612                         return component;
 613
 614         return NULL;
 615 }
 616
 617 static int imx_drm_add_component(struct device *dev, struct device_node *node)
 618 {
 619         struct imx_drm_component *component;
 620
 621         if (imx_drm_find_component(dev, node))
 622                 return 0;
 623
 624         component = devm_kzalloc(dev, sizeof(*component), GFP_KERNEL);
 625         if (!component)
 626                 return -ENOMEM;
 627
 628         component->of_node = node;
 629         list_add_tail(&component->list, &imx_drm_components);
 630
 631         return 0;
 632 }
 633
 634 static int imx_drm_platform_probe(struct platform_device *pdev)
 635 {
 636         struct device_node *ep, *port, *remote;
 637         int ret;
 638         int i;
 639
 640         /*
 641          * Bind the IPU display interface ports first, so that
 642          * imx_drm_encoder_parse_of called from encoder .bind callbacks
 643          * works as expected.
 644          */
 645         for (i = 0; ; i++) {
 646                 port = of_parse_phandle(pdev->dev.of_node, "ports", i);
 647                 if (!port)
 648                         break;
 649
 650                 ret = imx_drm_add_component(&pdev->dev, port);
 651                 if (ret < 0)
 652                         return ret;
 653         }
 654
 655         if (i == 0) {
 656                 dev_err(&pdev->dev, "missing 'ports' property\n");
 657                 return -ENODEV;
 658         }
 659
 660         /* Then bind all encoders */
 661         for (i = 0; ; i++) {
 662                 port = of_parse_phandle(pdev->dev.of_node, "ports", i);
 663                 if (!port)
 664                         break;
 665
 666                 for_each_child_of_node(port, ep) {
 667                         remote = of_graph_get_remote_port_parent(ep);
 668                         if (!remote || !of_device_is_available(remote)) {
 669                                 of_node_put(remote);
 670                                 continue;
 671                         } else if (!of_device_is_available(remote->parent)) {
 672                                 dev_warn(&pdev->dev, "parent device of %s is not available\n",
 673                                          remote->full_name);
 674                                 of_node_put(remote);
 675                                 continue;
 676                         }
 677
 678                         ret = imx_drm_add_component(&pdev->dev, remote);
 679                         of_node_put(remote);
 680                         if (ret < 0)
 681                                 return ret;
 682                 }
 683                 of_node_put(port);
 684         }
 685
 686         ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
 687         if (ret)
 688                 return ret;
 689
 690         return component_master_add(&pdev->dev, &imx_drm_ops);
 691 }
 692
 693 static int imx_drm_platform_remove(struct platform_device *pdev)
 694 {
 695         component_master_del(&pdev->dev, &imx_drm_ops);
 696         return 0;
 697 }
 698
 699 static const struct of_device_id imx_drm_dt_ids[] = {
 700         { .compatible = "fsl,imx-display-subsystem", },
 701         { /* sentinel */ },
 702 };
 703 MODULE_DEVICE_TABLE(of, imx_drm_dt_ids);
 704
 705 static struct platform_driver imx_drm_pdrv = {
 706         .probe          = imx_drm_platform_probe,
 707         .remove         = imx_drm_platform_remove,
 708         .driver         = {
 709                 .owner  = THIS_MODULE,
 710                 .name   = "imx-drm",
 711                 .of_match_table = imx_drm_dt_ids,
 712         },
 713 };
 714 module_platform_driver(imx_drm_pdrv);
 715
 716 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
 717 MODULE_DESCRIPTION("i.MX drm driver core");
 718 MODULE_LICENSE("GPL");