drivers/gpu/drm/drm_sysfs.c

   1
   2 /*
   3  * drm_sysfs.c - Modifications to drm_sysfs_class.c to support
   4  *               extra sysfs attribute from DRM. Normal drm_sysfs_class
   5  *               does not allow adding attributes.
   6  *
   7  * Copyright (c) 2004 Jon Smirl <jonsmirl@gmail.com>
   8  * Copyright (c) 2003-2004 Greg Kroah-Hartman <greg@kroah.com>
   9  * Copyright (c) 2003-2004 IBM Corp.
  10  *
  11  * This file is released under the GPLv2
  12  *
  13  */
  14
  15 #include <linux/device.h>
  16 #include <linux/kdev_t.h>
  17 #include <linux/gfp.h>
  18 #include <linux/err.h>
  19 #include <linux/export.h>
  20
  21 #include <drm/drm_sysfs.h>
  22 #include <drm/drm_core.h>
  23 #include <drm/drmP.h>
  24 #include "drm_internal.h"
  25
  26 #define to_drm_minor(d) dev_get_drvdata(d)
  27 #define to_drm_connector(d) dev_get_drvdata(d)
  28
  29 static struct device_type drm_sysfs_device_minor = {
  30         .name = "drm_minor"
  31 };
  32
  33 /**
  34  * __drm_class_suspend - internal DRM class suspend routine
  35  * @dev: Linux device to suspend
  36  * @state: power state to enter
  37  *
  38  * Just figures out what the actual struct drm_device associated with
  39  * @dev is and calls its suspend hook, if present.
  40  */
  41 static int __drm_class_suspend(struct device *dev, pm_message_t state)
  42 {
  43         if (dev->type == &drm_sysfs_device_minor) {
  44                 struct drm_minor *drm_minor = to_drm_minor(dev);
  45                 struct drm_device *drm_dev = drm_minor->dev;
  46
  47                 if (drm_minor->type == DRM_MINOR_LEGACY &&
  48                     !drm_core_check_feature(drm_dev, DRIVER_MODESET) &&
  49                     drm_dev->driver->suspend)
  50                         return drm_dev->driver->suspend(drm_dev, state);
  51         }
  52         return 0;
  53 }
  54
  55 /**
  56  * drm_class_suspend - internal DRM class suspend hook. Simply calls
  57  * __drm_class_suspend() with the correct pm state.
  58  * @dev: Linux device to suspend
  59  */
  60 static int drm_class_suspend(struct device *dev)
  61 {
  62         return __drm_class_suspend(dev, PMSG_SUSPEND);
  63 }
  64
  65 /**
  66  * drm_class_freeze - internal DRM class freeze hook. Simply calls
  67  * __drm_class_suspend() with the correct pm state.
  68  * @dev: Linux device to freeze
  69  */
  70 static int drm_class_freeze(struct device *dev)
  71 {
  72         return __drm_class_suspend(dev, PMSG_FREEZE);
  73 }
  74
  75 /**
  76  * drm_class_resume - DRM class resume hook
  77  * @dev: Linux device to resume
  78  *
  79  * Just figures out what the actual struct drm_device associated with
  80  * @dev is and calls its resume hook, if present.
  81  */
  82 static int drm_class_resume(struct device *dev)
  83 {
  84         if (dev->type == &drm_sysfs_device_minor) {
  85                 struct drm_minor *drm_minor = to_drm_minor(dev);
  86                 struct drm_device *drm_dev = drm_minor->dev;
  87
  88                 if (drm_minor->type == DRM_MINOR_LEGACY &&
  89                     !drm_core_check_feature(drm_dev, DRIVER_MODESET) &&
  90                     drm_dev->driver->resume)
  91                         return drm_dev->driver->resume(drm_dev);
  92         }
  93         return 0;
  94 }
  95
  96 static const struct dev_pm_ops drm_class_dev_pm_ops = {
  97         .suspend        = drm_class_suspend,
  98         .resume         = drm_class_resume,
  99         .freeze         = drm_class_freeze,
 100 };
 101
 102 static char *drm_devnode(struct device *dev, umode_t *mode)
 103 {
 104         return kasprintf(GFP_KERNEL, "dri/%s", dev_name(dev));
 105 }
 106
 107 static CLASS_ATTR_STRING(version, S_IRUGO,
 108                 CORE_NAME " "
 109                 __stringify(CORE_MAJOR) "."
 110                 __stringify(CORE_MINOR) "."
 111                 __stringify(CORE_PATCHLEVEL) " "
 112                 CORE_DATE);
 113
 114 /**
 115  * drm_sysfs_create - create a struct drm_sysfs_class structure
 116  * @owner: pointer to the module that is to "own" this struct drm_sysfs_class
 117  * @name: pointer to a string for the name of this class.
 118  *
 119  * This is used to create DRM class pointer that can then be used
 120  * in calls to drm_sysfs_device_add().
 121  *
 122  * Note, the pointer created here is to be destroyed when finished by making a
 123  * call to drm_sysfs_destroy().
 124  */
 125 struct class *drm_sysfs_create(struct module *owner, char *name)
 126 {
 127         struct class *class;
 128         int err;
 129
 130         class = class_create(owner, name);
 131         if (IS_ERR(class)) {
 132                 err = PTR_ERR(class);
 133                 goto err_out;
 134         }
 135
 136         class->pm = &drm_class_dev_pm_ops;
 137
 138         err = class_create_file(class, &class_attr_version.attr);
 139         if (err)
 140                 goto err_out_class;
 141
 142         class->devnode = drm_devnode;
 143
 144         return class;
 145
 146 err_out_class:
 147         class_destroy(class);
 148 err_out:
 149         return ERR_PTR(err);
 150 }
 151
 152 /**
 153  * drm_sysfs_destroy - destroys DRM class
 154  *
 155  * Destroy the DRM device class.
 156  */
 157 void drm_sysfs_destroy(void)
 158 {
 159         if ((drm_class == NULL) || (IS_ERR(drm_class)))
 160                 return;
 161         class_remove_file(drm_class, &class_attr_version.attr);
 162         class_destroy(drm_class);
 163         drm_class = NULL;
 164 }
 165
 166 /*
 167  * Connector properties
 168  */
 169 static ssize_t status_store(struct device *device,
 170                            struct device_attribute *attr,
 171                            const char *buf, size_t count)
 172 {
 173         struct drm_connector *connector = to_drm_connector(device);
 174         struct drm_device *dev = connector->dev;
 175         enum drm_connector_status old_status;
 176         int ret;
 177
 178         ret = mutex_lock_interruptible(&dev->mode_config.mutex);
 179         if (ret)
 180                 return ret;
 181
 182         old_status = connector->status;
 183
 184         if (sysfs_streq(buf, "detect")) {
 185                 connector->force = 0;
 186                 connector->status = connector->funcs->detect(connector, true);
 187         } else if (sysfs_streq(buf, "on")) {
 188                 connector->force = DRM_FORCE_ON;
 189         } else if (sysfs_streq(buf, "on-digital")) {
 190                 connector->force = DRM_FORCE_ON_DIGITAL;
 191         } else if (sysfs_streq(buf, "off")) {
 192                 connector->force = DRM_FORCE_OFF;
 193         } else
 194                 ret = -EINVAL;
 195
 196         if (ret == 0 && connector->force) {
 197                 if (connector->force == DRM_FORCE_ON ||
 198                     connector->force == DRM_FORCE_ON_DIGITAL)
 199                         connector->status = connector_status_connected;
 200                 else
 201                         connector->status = connector_status_disconnected;
 202                 if (connector->funcs->force)
 203                         connector->funcs->force(connector);
 204         }
 205
 206         if (old_status != connector->status) {
 207                 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %d to %d\n",
 208                               connector->base.id,
 209                               connector->name,
 210                               old_status, connector->status);
 211
 212                 dev->mode_config.delayed_event = true;
 213                 if (dev->mode_config.poll_enabled)
 214                         schedule_delayed_work(&dev->mode_config.output_poll_work,
 215                                               0);
 216         }
 217
 218         mutex_unlock(&dev->mode_config.mutex);
 219
 220         return ret ? ret : count;
 221 }
 222
 223 static ssize_t status_show(struct device *device,
 224                            struct device_attribute *attr,
 225                            char *buf)
 226 {
 227         struct drm_connector *connector = to_drm_connector(device);
 228
 229         return snprintf(buf, PAGE_SIZE, "%s\n",
 230                         drm_get_connector_status_name(connector->status));
 231 }
 232
 233 static ssize_t dpms_show(struct device *device,
 234                            struct device_attribute *attr,
 235                            char *buf)
 236 {
 237         struct drm_connector *connector = to_drm_connector(device);
 238         struct drm_device *dev = connector->dev;
 239         uint64_t dpms_status;
 240         int ret;
 241
 242         ret = drm_object_property_get_value(&connector->base,
 243                                             dev->mode_config.dpms_property,
 244                                             &dpms_status);
 245         if (ret)
 246                 return 0;
 247
 248         return snprintf(buf, PAGE_SIZE, "%s\n",
 249                         drm_get_dpms_name((int)dpms_status));
 250 }
 251
 252 static ssize_t enabled_show(struct device *device,
 253                             struct device_attribute *attr,
 254                            char *buf)
 255 {
 256         struct drm_connector *connector = to_drm_connector(device);
 257
 258         return snprintf(buf, PAGE_SIZE, "%s\n", connector->encoder ? "enabled" :
 259                         "disabled");
 260 }
 261
 262 static ssize_t edid_show(struct file *filp, struct kobject *kobj,
 263                          struct bin_attribute *attr, char *buf, loff_t off,
 264                          size_t count)
 265 {
 266         struct device *connector_dev = container_of(kobj, struct device, kobj);
 267         struct drm_connector *connector = to_drm_connector(connector_dev);
 268         unsigned char *edid;
 269         size_t size;
 270
 271         if (!connector->edid_blob_ptr)
 272                 return 0;
 273
 274         edid = connector->edid_blob_ptr->data;
 275         size = connector->edid_blob_ptr->length;
 276         if (!edid)
 277                 return 0;
 278
 279         if (off >= size)
 280                 return 0;
 281
 282         if (off + count > size)
 283                 count = size - off;
 284         memcpy(buf, edid + off, count);
 285
 286         return count;
 287 }
 288
 289 static ssize_t modes_show(struct device *device,
 290                            struct device_attribute *attr,
 291                            char *buf)
 292 {
 293         struct drm_connector *connector = to_drm_connector(device);
 294         struct drm_display_mode *mode;
 295         int written = 0;
 296
 297         list_for_each_entry(mode, &connector->modes, head) {
 298                 written += snprintf(buf + written, PAGE_SIZE - written, "%s\n",
 299                                     mode->name);
 300         }
 301
 302         return written;
 303 }
 304
 305 static ssize_t tv_subconnector_show(struct device *device,
 306                                     struct device_attribute *attr,
 307                                     char *buf)
 308 {
 309         struct drm_connector *connector = to_drm_connector(device);
 310         struct drm_device *dev = connector->dev;
 311         struct drm_property *prop;
 312         uint64_t subconnector;
 313         int ret;
 314
 315         prop = dev->mode_config.tv_subconnector_property;
 316         if (!prop) {
 317                 DRM_ERROR("Unable to find subconnector property\n");
 318                 return 0;
 319         }
 320
 321         ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
 322         if (ret)
 323                 return 0;
 324
 325         return snprintf(buf, PAGE_SIZE, "%s",
 326                         drm_get_tv_subconnector_name((int)subconnector));
 327 }
 328
 329 static ssize_t tv_select_subconnector_show(struct device *device,
 330                                            struct device_attribute *attr,
 331                                            char *buf)
 332 {
 333         struct drm_connector *connector = to_drm_connector(device);
 334         struct drm_device *dev = connector->dev;
 335         struct drm_property *prop;
 336         uint64_t subconnector;
 337         int ret;
 338
 339         prop = dev->mode_config.tv_select_subconnector_property;
 340         if (!prop) {
 341                 DRM_ERROR("Unable to find select subconnector property\n");
 342                 return 0;
 343         }
 344
 345         ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
 346         if (ret)
 347                 return 0;
 348
 349         return snprintf(buf, PAGE_SIZE, "%s",
 350                         drm_get_tv_select_name((int)subconnector));
 351 }
 352
 353 static ssize_t dvii_subconnector_show(struct device *device,
 354                                       struct device_attribute *attr,
 355                                       char *buf)
 356 {
 357         struct drm_connector *connector = to_drm_connector(device);
 358         struct drm_device *dev = connector->dev;
 359         struct drm_property *prop;
 360         uint64_t subconnector;
 361         int ret;
 362
 363         prop = dev->mode_config.dvi_i_subconnector_property;
 364         if (!prop) {
 365                 DRM_ERROR("Unable to find subconnector property\n");
 366                 return 0;
 367         }
 368
 369         ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
 370         if (ret)
 371                 return 0;
 372
 373         return snprintf(buf, PAGE_SIZE, "%s",
 374                         drm_get_dvi_i_subconnector_name((int)subconnector));
 375 }
 376
 377 static ssize_t dvii_select_subconnector_show(struct device *device,
 378                                              struct device_attribute *attr,
 379                                              char *buf)
 380 {
 381         struct drm_connector *connector = to_drm_connector(device);
 382         struct drm_device *dev = connector->dev;
 383         struct drm_property *prop;
 384         uint64_t subconnector;
 385         int ret;
 386
 387         prop = dev->mode_config.dvi_i_select_subconnector_property;
 388         if (!prop) {
 389                 DRM_ERROR("Unable to find select subconnector property\n");
 390                 return 0;
 391         }
 392
 393         ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
 394         if (ret)
 395                 return 0;
 396
 397         return snprintf(buf, PAGE_SIZE, "%s",
 398                         drm_get_dvi_i_select_name((int)subconnector));
 399 }
 400
 401 static DEVICE_ATTR_RW(status);
 402 static DEVICE_ATTR_RO(enabled);
 403 static DEVICE_ATTR_RO(dpms);
 404 static DEVICE_ATTR_RO(modes);
 405
 406 static struct attribute *connector_dev_attrs[] = {
 407         &dev_attr_status.attr,
 408         &dev_attr_enabled.attr,
 409         &dev_attr_dpms.attr,
 410         &dev_attr_modes.attr,
 411         NULL
 412 };
 413
 414 static DEVICE_ATTR_RO(tv_subconnector);
 415 static DEVICE_ATTR_RO(tv_select_subconnector);
 416
 417 static struct attribute *connector_tv_dev_attrs[] = {
 418         &dev_attr_tv_subconnector.attr,
 419         &dev_attr_tv_select_subconnector.attr,
 420         NULL
 421 };
 422
 423 static DEVICE_ATTR_RO(dvii_subconnector);
 424 static DEVICE_ATTR_RO(dvii_select_subconnector);
 425
 426 static struct attribute *connector_dvii_dev_attrs[] = {
 427         &dev_attr_dvii_subconnector.attr,
 428         &dev_attr_dvii_select_subconnector.attr,
 429         NULL
 430 };
 431
 432 /* Connector type related helpers */
 433 static int kobj_connector_type(struct kobject *kobj)
 434 {
 435         struct device *dev = kobj_to_dev(kobj);
 436         struct drm_connector *connector = to_drm_connector(dev);
 437
 438         return connector->connector_type;
 439 }
 440
 441 static umode_t connector_is_dvii(struct kobject *kobj,
 442                                  struct attribute *attr, int idx)
 443 {
 444         return kobj_connector_type(kobj) == DRM_MODE_CONNECTOR_DVII ?
 445                 attr->mode : 0;
 446 }
 447
 448 static umode_t connector_is_tv(struct kobject *kobj,
 449                                struct attribute *attr, int idx)
 450 {
 451         switch (kobj_connector_type(kobj)) {
 452         case DRM_MODE_CONNECTOR_Composite:
 453         case DRM_MODE_CONNECTOR_SVIDEO:
 454         case DRM_MODE_CONNECTOR_Component:
 455         case DRM_MODE_CONNECTOR_TV:
 456                 return attr->mode;
 457         }
 458
 459         return 0;
 460 }
 461
 462 static struct bin_attribute edid_attr = {
 463         .attr.name = "edid",
 464         .attr.mode = 0444,
 465         .size = 0,
 466         .read = edid_show,
 467 };
 468
 469 static struct bin_attribute *connector_bin_attrs[] = {
 470         &edid_attr,
 471         NULL
 472 };
 473
 474 static const struct attribute_group connector_dev_group = {
 475         .attrs = connector_dev_attrs,
 476         .bin_attrs = connector_bin_attrs,
 477 };
 478
 479 static const struct attribute_group connector_tv_dev_group = {
 480         .attrs = connector_tv_dev_attrs,
 481         .is_visible = connector_is_tv,
 482 };
 483
 484 static const struct attribute_group connector_dvii_dev_group = {
 485         .attrs = connector_dvii_dev_attrs,
 486         .is_visible = connector_is_dvii,
 487 };
 488
 489 static const struct attribute_group *connector_dev_groups[] = {
 490         &connector_dev_group,
 491         &connector_tv_dev_group,
 492         &connector_dvii_dev_group,
 493         NULL
 494 };
 495
 496 /**
 497  * drm_sysfs_connector_add - add a connector to sysfs
 498  * @connector: connector to add
 499  *
 500  * Create a connector device in sysfs, along with its associated connector
 501  * properties (so far, connection status, dpms, mode list & edid) and
 502  * generate a hotplug event so userspace knows there's a new connector
 503  * available.
 504  */
 505 int drm_sysfs_connector_add(struct drm_connector *connector)
 506 {
 507         struct drm_device *dev = connector->dev;
 508
 509         if (connector->kdev)
 510                 return 0;
 511
 512         connector->kdev =
 513                 device_create_with_groups(drm_class, dev->primary->kdev, 0,
 514                                           connector, connector_dev_groups,
 515                                           "card%d-%s", dev->primary->index,
 516                                           connector->name);
 517         DRM_DEBUG("adding \"%s\" to sysfs\n",
 518                   connector->name);
 519
 520         if (IS_ERR(connector->kdev)) {
 521                 DRM_ERROR("failed to register connector device: %ld\n", PTR_ERR(connector->kdev));
 522                 return PTR_ERR(connector->kdev);
 523         }
 524
 525         /* Let userspace know we have a new connector */
 526         drm_sysfs_hotplug_event(dev);
 527
 528         return 0;
 529 }
 530
 531 /**
 532  * drm_sysfs_connector_remove - remove an connector device from sysfs
 533  * @connector: connector to remove
 534  *
 535  * Remove @connector and its associated attributes from sysfs.  Note that
 536  * the device model core will take care of sending the "remove" uevent
 537  * at this time, so we don't need to do it.
 538  *
 539  * Note:
 540  * This routine should only be called if the connector was previously
 541  * successfully registered.  If @connector hasn't been registered yet,
 542  * you'll likely see a panic somewhere deep in sysfs code when called.
 543  */
 544 void drm_sysfs_connector_remove(struct drm_connector *connector)
 545 {
 546         if (!connector->kdev)
 547                 return;
 548         DRM_DEBUG("removing \"%s\" from sysfs\n",
 549                   connector->name);
 550
 551         device_unregister(connector->kdev);
 552         connector->kdev = NULL;
 553 }
 554
 555 /**
 556  * drm_sysfs_hotplug_event - generate a DRM uevent
 557  * @dev: DRM device
 558  *
 559  * Send a uevent for the DRM device specified by @dev.  Currently we only
 560  * set HOTPLUG=1 in the uevent environment, but this could be expanded to
 561  * deal with other types of events.
 562  */
 563 void drm_sysfs_hotplug_event(struct drm_device *dev)
 564 {
 565         char *event_string = "HOTPLUG=1";
 566         char *envp[] = { event_string, NULL };
 567
 568         DRM_DEBUG("generating hotplug event\n");
 569
 570         kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
 571 }
 572 EXPORT_SYMBOL(drm_sysfs_hotplug_event);
 573
 574 static void drm_sysfs_release(struct device *dev)
 575 {
 576         kfree(dev);
 577 }
 578
 579 /**
 580  * drm_sysfs_minor_alloc() - Allocate sysfs device for given minor
 581  * @minor: minor to allocate sysfs device for
 582  *
 583  * This allocates a new sysfs device for @minor and returns it. The device is
 584  * not registered nor linked. The caller has to use device_add() and
 585  * device_del() to register and unregister it.
 586  *
 587  * Note that dev_get_drvdata() on the new device will return the minor.
 588  * However, the device does not hold a ref-count to the minor nor to the
 589  * underlying drm_device. This is unproblematic as long as you access the
 590  * private data only in sysfs callbacks. device_del() disables those
 591  * synchronously, so they cannot be called after you cleanup a minor.
 592  */
 593 struct device *drm_sysfs_minor_alloc(struct drm_minor *minor)
 594 {
 595         const char *minor_str;
 596         struct device *kdev;
 597         int r;
 598
 599         if (minor->type == DRM_MINOR_CONTROL)
 600                 minor_str = "controlD%d";
 601         else if (minor->type == DRM_MINOR_RENDER)
 602                 minor_str = "renderD%d";
 603         else
 604                 minor_str = "card%d";
 605
 606         kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
 607         if (!kdev)
 608                 return ERR_PTR(-ENOMEM);
 609
 610         device_initialize(kdev);
 611         kdev->devt = MKDEV(DRM_MAJOR, minor->index);
 612         kdev->class = drm_class;
 613         kdev->type = &drm_sysfs_device_minor;
 614         kdev->parent = minor->dev->dev;
 615         kdev->release = drm_sysfs_release;
 616         dev_set_drvdata(kdev, minor);
 617
 618         r = dev_set_name(kdev, minor_str, minor->index);
 619         if (r < 0)
 620                 goto err_free;
 621
 622         return kdev;
 623
 624 err_free:
 625         put_device(kdev);
 626         return ERR_PTR(r);
 627 }
 628
 629 /**
 630  * drm_class_device_register - Register a struct device in the drm class.
 631  *
 632  * @dev: pointer to struct device to register.
 633  *
 634  * @dev should have all relevant members pre-filled with the exception
 635  * of the class member. In particular, the device_type member must
 636  * be set.
 637  */
 638
 639 int drm_class_device_register(struct device *dev)
 640 {
 641         if (!drm_class || IS_ERR(drm_class))
 642                 return -ENOENT;
 643
 644         dev->class = drm_class;
 645         return device_register(dev);
 646 }
 647 EXPORT_SYMBOL_GPL(drm_class_device_register);
 648
 649 void drm_class_device_unregister(struct device *dev)
 650 {
 651         return device_unregister(dev);
 652 }
 653 EXPORT_SYMBOL_GPL(drm_class_device_unregister);