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         int dpms;
 239
 240         dpms = READ_ONCE(connector->dpms);
 241
 242         return snprintf(buf, PAGE_SIZE, "%s\n",
 243                         drm_get_dpms_name(dpms));
 244 }
 245
 246 static ssize_t enabled_show(struct device *device,
 247                             struct device_attribute *attr,
 248                            char *buf)
 249 {
 250         struct drm_connector *connector = to_drm_connector(device);
 251
 252         return snprintf(buf, PAGE_SIZE, "%s\n", connector->encoder ? "enabled" :
 253                         "disabled");
 254 }
 255
 256 static ssize_t edid_show(struct file *filp, struct kobject *kobj,
 257                          struct bin_attribute *attr, char *buf, loff_t off,
 258                          size_t count)
 259 {
 260         struct device *connector_dev = container_of(kobj, struct device, kobj);
 261         struct drm_connector *connector = to_drm_connector(connector_dev);
 262         unsigned char *edid;
 263         size_t size;
 264
 265         if (!connector->edid_blob_ptr)
 266                 return 0;
 267
 268         edid = connector->edid_blob_ptr->data;
 269         size = connector->edid_blob_ptr->length;
 270         if (!edid)
 271                 return 0;
 272
 273         if (off >= size)
 274                 return 0;
 275
 276         if (off + count > size)
 277                 count = size - off;
 278         memcpy(buf, edid + off, count);
 279
 280         return count;
 281 }
 282
 283 static ssize_t modes_show(struct device *device,
 284                            struct device_attribute *attr,
 285                            char *buf)
 286 {
 287         struct drm_connector *connector = to_drm_connector(device);
 288         struct drm_display_mode *mode;
 289         int written = 0;
 290
 291         list_for_each_entry(mode, &connector->modes, head) {
 292                 written += snprintf(buf + written, PAGE_SIZE - written, "%s\n",
 293                                     mode->name);
 294         }
 295
 296         return written;
 297 }
 298
 299 static ssize_t subconnector_show(struct device *device,
 300                            struct device_attribute *attr,
 301                            char *buf)
 302 {
 303         struct drm_connector *connector = to_drm_connector(device);
 304         struct drm_device *dev = connector->dev;
 305         struct drm_property *prop = NULL;
 306         uint64_t subconnector;
 307         int is_tv = 0;
 308         int ret;
 309
 310         switch (connector->connector_type) {
 311                 case DRM_MODE_CONNECTOR_DVII:
 312                         prop = dev->mode_config.dvi_i_subconnector_property;
 313                         break;
 314                 case DRM_MODE_CONNECTOR_Composite:
 315                 case DRM_MODE_CONNECTOR_SVIDEO:
 316                 case DRM_MODE_CONNECTOR_Component:
 317                 case DRM_MODE_CONNECTOR_TV:
 318                         prop = dev->mode_config.tv_subconnector_property;
 319                         is_tv = 1;
 320                         break;
 321                 default:
 322                         DRM_ERROR("Wrong connector type for this property\n");
 323                         return 0;
 324         }
 325
 326         if (!prop) {
 327                 DRM_ERROR("Unable to find subconnector property\n");
 328                 return 0;
 329         }
 330
 331         ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
 332         if (ret)
 333                 return 0;
 334
 335         return snprintf(buf, PAGE_SIZE, "%s", is_tv ?
 336                         drm_get_tv_subconnector_name((int)subconnector) :
 337                         drm_get_dvi_i_subconnector_name((int)subconnector));
 338 }
 339
 340 static ssize_t select_subconnector_show(struct device *device,
 341                            struct device_attribute *attr,
 342                            char *buf)
 343 {
 344         struct drm_connector *connector = to_drm_connector(device);
 345         struct drm_device *dev = connector->dev;
 346         struct drm_property *prop = NULL;
 347         uint64_t subconnector;
 348         int is_tv = 0;
 349         int ret;
 350
 351         switch (connector->connector_type) {
 352                 case DRM_MODE_CONNECTOR_DVII:
 353                         prop = dev->mode_config.dvi_i_select_subconnector_property;
 354                         break;
 355                 case DRM_MODE_CONNECTOR_Composite:
 356                 case DRM_MODE_CONNECTOR_SVIDEO:
 357                 case DRM_MODE_CONNECTOR_Component:
 358                 case DRM_MODE_CONNECTOR_TV:
 359                         prop = dev->mode_config.tv_select_subconnector_property;
 360                         is_tv = 1;
 361                         break;
 362                 default:
 363                         DRM_ERROR("Wrong connector type for this property\n");
 364                         return 0;
 365         }
 366
 367         if (!prop) {
 368                 DRM_ERROR("Unable to find select subconnector property\n");
 369                 return 0;
 370         }
 371
 372         ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
 373         if (ret)
 374                 return 0;
 375
 376         return snprintf(buf, PAGE_SIZE, "%s", is_tv ?
 377                         drm_get_tv_select_name((int)subconnector) :
 378                         drm_get_dvi_i_select_name((int)subconnector));
 379 }
 380
 381 static DEVICE_ATTR_RW(status);
 382 static DEVICE_ATTR_RO(enabled);
 383 static DEVICE_ATTR_RO(dpms);
 384 static DEVICE_ATTR_RO(modes);
 385
 386 static struct attribute *connector_dev_attrs[] = {
 387         &dev_attr_status.attr,
 388         &dev_attr_enabled.attr,
 389         &dev_attr_dpms.attr,
 390         &dev_attr_modes.attr,
 391         NULL
 392 };
 393
 394 /* These attributes are for both DVI-I connectors and all types of tv-out. */
 395 static DEVICE_ATTR_RO(subconnector);
 396 static DEVICE_ATTR_RO(select_subconnector);
 397
 398 static struct attribute *connector_opt_dev_attrs[] = {
 399         &dev_attr_subconnector.attr,
 400         &dev_attr_select_subconnector.attr,
 401         NULL
 402 };
 403
 404 static umode_t connector_opt_dev_is_visible(struct kobject *kobj,
 405                                             struct attribute *attr, int idx)
 406 {
 407         struct device *dev = kobj_to_dev(kobj);
 408         struct drm_connector *connector = to_drm_connector(dev);
 409
 410         /*
 411          * In the long run it maybe a good idea to make one set of
 412          * optionals per connector type.
 413          */
 414         switch (connector->connector_type) {
 415         case DRM_MODE_CONNECTOR_DVII:
 416         case DRM_MODE_CONNECTOR_Composite:
 417         case DRM_MODE_CONNECTOR_SVIDEO:
 418         case DRM_MODE_CONNECTOR_Component:
 419         case DRM_MODE_CONNECTOR_TV:
 420                 return attr->mode;
 421         }
 422
 423         return 0;
 424 }
 425
 426 static struct bin_attribute edid_attr = {
 427         .attr.name = "edid",
 428         .attr.mode = 0444,
 429         .size = 0,
 430         .read = edid_show,
 431 };
 432
 433 static struct bin_attribute *connector_bin_attrs[] = {
 434         &edid_attr,
 435         NULL
 436 };
 437
 438 static const struct attribute_group connector_dev_group = {
 439         .attrs = connector_dev_attrs,
 440         .bin_attrs = connector_bin_attrs,
 441 };
 442
 443 static const struct attribute_group connector_opt_dev_group = {
 444         .attrs = connector_opt_dev_attrs,
 445         .is_visible = connector_opt_dev_is_visible,
 446 };
 447
 448 static const struct attribute_group *connector_dev_groups[] = {
 449         &connector_dev_group,
 450         &connector_opt_dev_group,
 451         NULL
 452 };
 453
 454 /**
 455  * drm_sysfs_connector_add - add a connector to sysfs
 456  * @connector: connector to add
 457  *
 458  * Create a connector device in sysfs, along with its associated connector
 459  * properties (so far, connection status, dpms, mode list & edid) and
 460  * generate a hotplug event so userspace knows there's a new connector
 461  * available.
 462  */
 463 int drm_sysfs_connector_add(struct drm_connector *connector)
 464 {
 465         struct drm_device *dev = connector->dev;
 466
 467         if (connector->kdev)
 468                 return 0;
 469
 470         connector->kdev =
 471                 device_create_with_groups(drm_class, dev->primary->kdev, 0,
 472                                           connector, connector_dev_groups,
 473                                           "card%d-%s", dev->primary->index,
 474                                           connector->name);
 475         DRM_DEBUG("adding \"%s\" to sysfs\n",
 476                   connector->name);
 477
 478         if (IS_ERR(connector->kdev)) {
 479                 DRM_ERROR("failed to register connector device: %ld\n", PTR_ERR(connector->kdev));
 480                 return PTR_ERR(connector->kdev);
 481         }
 482
 483         /* Let userspace know we have a new connector */
 484         drm_sysfs_hotplug_event(dev);
 485
 486         return 0;
 487 }
 488
 489 /**
 490  * drm_sysfs_connector_remove - remove an connector device from sysfs
 491  * @connector: connector to remove
 492  *
 493  * Remove @connector and its associated attributes from sysfs.  Note that
 494  * the device model core will take care of sending the "remove" uevent
 495  * at this time, so we don't need to do it.
 496  *
 497  * Note:
 498  * This routine should only be called if the connector was previously
 499  * successfully registered.  If @connector hasn't been registered yet,
 500  * you'll likely see a panic somewhere deep in sysfs code when called.
 501  */
 502 void drm_sysfs_connector_remove(struct drm_connector *connector)
 503 {
 504         if (!connector->kdev)
 505                 return;
 506         DRM_DEBUG("removing \"%s\" from sysfs\n",
 507                   connector->name);
 508
 509         device_unregister(connector->kdev);
 510         connector->kdev = NULL;
 511 }
 512
 513 /**
 514  * drm_sysfs_hotplug_event - generate a DRM uevent
 515  * @dev: DRM device
 516  *
 517  * Send a uevent for the DRM device specified by @dev.  Currently we only
 518  * set HOTPLUG=1 in the uevent environment, but this could be expanded to
 519  * deal with other types of events.
 520  */
 521 void drm_sysfs_hotplug_event(struct drm_device *dev)
 522 {
 523         char *event_string = "HOTPLUG=1";
 524         char *envp[] = { event_string, NULL };
 525
 526         DRM_DEBUG("generating hotplug event\n");
 527
 528         kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
 529 }
 530 EXPORT_SYMBOL(drm_sysfs_hotplug_event);
 531
 532 static void drm_sysfs_release(struct device *dev)
 533 {
 534         kfree(dev);
 535 }
 536
 537 /**
 538  * drm_sysfs_minor_alloc() - Allocate sysfs device for given minor
 539  * @minor: minor to allocate sysfs device for
 540  *
 541  * This allocates a new sysfs device for @minor and returns it. The device is
 542  * not registered nor linked. The caller has to use device_add() and
 543  * device_del() to register and unregister it.
 544  *
 545  * Note that dev_get_drvdata() on the new device will return the minor.
 546  * However, the device does not hold a ref-count to the minor nor to the
 547  * underlying drm_device. This is unproblematic as long as you access the
 548  * private data only in sysfs callbacks. device_del() disables those
 549  * synchronously, so they cannot be called after you cleanup a minor.
 550  */
 551 struct device *drm_sysfs_minor_alloc(struct drm_minor *minor)
 552 {
 553         const char *minor_str;
 554         struct device *kdev;
 555         int r;
 556
 557         if (minor->type == DRM_MINOR_CONTROL)
 558                 minor_str = "controlD%d";
 559         else if (minor->type == DRM_MINOR_RENDER)
 560                 minor_str = "renderD%d";
 561         else
 562                 minor_str = "card%d";
 563
 564         kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
 565         if (!kdev)
 566                 return ERR_PTR(-ENOMEM);
 567
 568         device_initialize(kdev);
 569         kdev->devt = MKDEV(DRM_MAJOR, minor->index);
 570         kdev->class = drm_class;
 571         kdev->type = &drm_sysfs_device_minor;
 572         kdev->parent = minor->dev->dev;
 573         kdev->release = drm_sysfs_release;
 574         dev_set_drvdata(kdev, minor);
 575
 576         r = dev_set_name(kdev, minor_str, minor->index);
 577         if (r < 0)
 578                 goto err_free;
 579
 580         return kdev;
 581
 582 err_free:
 583         put_device(kdev);
 584         return ERR_PTR(r);
 585 }
 586
 587 /**
 588  * drm_class_device_register - Register a struct device in the drm class.
 589  *
 590  * @dev: pointer to struct device to register.
 591  *
 592  * @dev should have all relevant members pre-filled with the exception
 593  * of the class member. In particular, the device_type member must
 594  * be set.
 595  */
 596
 597 int drm_class_device_register(struct device *dev)
 598 {
 599         if (!drm_class || IS_ERR(drm_class))
 600                 return -ENOENT;
 601
 602         dev->class = drm_class;
 603         return device_register(dev);
 604 }
 605 EXPORT_SYMBOL_GPL(drm_class_device_register);
 606
 607 void drm_class_device_unregister(struct device *dev)
 608 {
 609         return device_unregister(dev);
 610 }
 611 EXPORT_SYMBOL_GPL(drm_class_device_unregister);