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 tv_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;
 306         uint64_t subconnector;
 307         int ret;
 308
 309         prop = dev->mode_config.tv_subconnector_property;
 310         if (!prop) {
 311                 DRM_ERROR("Unable to find subconnector property\n");
 312                 return 0;
 313         }
 314
 315         ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
 316         if (ret)
 317                 return 0;
 318
 319         return snprintf(buf, PAGE_SIZE, "%s",
 320                         drm_get_tv_subconnector_name((int)subconnector));
 321 }
 322
 323 static ssize_t tv_select_subconnector_show(struct device *device,
 324                                            struct device_attribute *attr,
 325                                            char *buf)
 326 {
 327         struct drm_connector *connector = to_drm_connector(device);
 328         struct drm_device *dev = connector->dev;
 329         struct drm_property *prop;
 330         uint64_t subconnector;
 331         int ret;
 332
 333         prop = dev->mode_config.tv_select_subconnector_property;
 334         if (!prop) {
 335                 DRM_ERROR("Unable to find select subconnector property\n");
 336                 return 0;
 337         }
 338
 339         ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
 340         if (ret)
 341                 return 0;
 342
 343         return snprintf(buf, PAGE_SIZE, "%s",
 344                         drm_get_tv_select_name((int)subconnector));
 345 }
 346
 347 static ssize_t dvii_subconnector_show(struct device *device,
 348                                       struct device_attribute *attr,
 349                                       char *buf)
 350 {
 351         struct drm_connector *connector = to_drm_connector(device);
 352         struct drm_device *dev = connector->dev;
 353         struct drm_property *prop;
 354         uint64_t subconnector;
 355         int ret;
 356
 357         prop = dev->mode_config.dvi_i_subconnector_property;
 358         if (!prop) {
 359                 DRM_ERROR("Unable to find subconnector property\n");
 360                 return 0;
 361         }
 362
 363         ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
 364         if (ret)
 365                 return 0;
 366
 367         return snprintf(buf, PAGE_SIZE, "%s",
 368                         drm_get_dvi_i_subconnector_name((int)subconnector));
 369 }
 370
 371 static ssize_t dvii_select_subconnector_show(struct device *device,
 372                                              struct device_attribute *attr,
 373                                              char *buf)
 374 {
 375         struct drm_connector *connector = to_drm_connector(device);
 376         struct drm_device *dev = connector->dev;
 377         struct drm_property *prop;
 378         uint64_t subconnector;
 379         int ret;
 380
 381         prop = dev->mode_config.dvi_i_select_subconnector_property;
 382         if (!prop) {
 383                 DRM_ERROR("Unable to find select subconnector property\n");
 384                 return 0;
 385         }
 386
 387         ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
 388         if (ret)
 389                 return 0;
 390
 391         return snprintf(buf, PAGE_SIZE, "%s",
 392                         drm_get_dvi_i_select_name((int)subconnector));
 393 }
 394
 395 static DEVICE_ATTR_RW(status);
 396 static DEVICE_ATTR_RO(enabled);
 397 static DEVICE_ATTR_RO(dpms);
 398 static DEVICE_ATTR_RO(modes);
 399
 400 static struct attribute *connector_dev_attrs[] = {
 401         &dev_attr_status.attr,
 402         &dev_attr_enabled.attr,
 403         &dev_attr_dpms.attr,
 404         &dev_attr_modes.attr,
 405         NULL
 406 };
 407
 408 static DEVICE_ATTR_RO(tv_subconnector);
 409 static DEVICE_ATTR_RO(tv_select_subconnector);
 410
 411 static struct attribute *connector_tv_dev_attrs[] = {
 412         &dev_attr_tv_subconnector.attr,
 413         &dev_attr_tv_select_subconnector.attr,
 414         NULL
 415 };
 416
 417 static DEVICE_ATTR_RO(dvii_subconnector);
 418 static DEVICE_ATTR_RO(dvii_select_subconnector);
 419
 420 static struct attribute *connector_dvii_dev_attrs[] = {
 421         &dev_attr_dvii_subconnector.attr,
 422         &dev_attr_dvii_select_subconnector.attr,
 423         NULL
 424 };
 425
 426 /* Connector type related helpers */
 427 static int kobj_connector_type(struct kobject *kobj)
 428 {
 429         struct device *dev = kobj_to_dev(kobj);
 430         struct drm_connector *connector = to_drm_connector(dev);
 431
 432         return connector->connector_type;
 433 }
 434
 435 static umode_t connector_is_dvii(struct kobject *kobj,
 436                                  struct attribute *attr, int idx)
 437 {
 438         return kobj_connector_type(kobj) == DRM_MODE_CONNECTOR_DVII ?
 439                 attr->mode : 0;
 440 }
 441
 442 static umode_t connector_is_tv(struct kobject *kobj,
 443                                struct attribute *attr, int idx)
 444 {
 445         switch (kobj_connector_type(kobj)) {
 446         case DRM_MODE_CONNECTOR_Composite:
 447         case DRM_MODE_CONNECTOR_SVIDEO:
 448         case DRM_MODE_CONNECTOR_Component:
 449         case DRM_MODE_CONNECTOR_TV:
 450                 return attr->mode;
 451         }
 452
 453         return 0;
 454 }
 455
 456 static struct bin_attribute edid_attr = {
 457         .attr.name = "edid",
 458         .attr.mode = 0444,
 459         .size = 0,
 460         .read = edid_show,
 461 };
 462
 463 static struct bin_attribute *connector_bin_attrs[] = {
 464         &edid_attr,
 465         NULL
 466 };
 467
 468 static const struct attribute_group connector_dev_group = {
 469         .attrs = connector_dev_attrs,
 470         .bin_attrs = connector_bin_attrs,
 471 };
 472
 473 static const struct attribute_group connector_tv_dev_group = {
 474         .attrs = connector_tv_dev_attrs,
 475         .is_visible = connector_is_tv,
 476 };
 477
 478 static const struct attribute_group connector_dvii_dev_group = {
 479         .attrs = connector_dvii_dev_attrs,
 480         .is_visible = connector_is_dvii,
 481 };
 482
 483 static const struct attribute_group *connector_dev_groups[] = {
 484         &connector_dev_group,
 485         &connector_tv_dev_group,
 486         &connector_dvii_dev_group,
 487         NULL
 488 };
 489
 490 /**
 491  * drm_sysfs_connector_add - add a connector to sysfs
 492  * @connector: connector to add
 493  *
 494  * Create a connector device in sysfs, along with its associated connector
 495  * properties (so far, connection status, dpms, mode list & edid) and
 496  * generate a hotplug event so userspace knows there's a new connector
 497  * available.
 498  */
 499 int drm_sysfs_connector_add(struct drm_connector *connector)
 500 {
 501         struct drm_device *dev = connector->dev;
 502
 503         if (connector->kdev)
 504                 return 0;
 505
 506         connector->kdev =
 507                 device_create_with_groups(drm_class, dev->primary->kdev, 0,
 508                                           connector, connector_dev_groups,
 509                                           "card%d-%s", dev->primary->index,
 510                                           connector->name);
 511         DRM_DEBUG("adding \"%s\" to sysfs\n",
 512                   connector->name);
 513
 514         if (IS_ERR(connector->kdev)) {
 515                 DRM_ERROR("failed to register connector device: %ld\n", PTR_ERR(connector->kdev));
 516                 return PTR_ERR(connector->kdev);
 517         }
 518
 519         /* Let userspace know we have a new connector */
 520         drm_sysfs_hotplug_event(dev);
 521
 522         return 0;
 523 }
 524
 525 /**
 526  * drm_sysfs_connector_remove - remove an connector device from sysfs
 527  * @connector: connector to remove
 528  *
 529  * Remove @connector and its associated attributes from sysfs.  Note that
 530  * the device model core will take care of sending the "remove" uevent
 531  * at this time, so we don't need to do it.
 532  *
 533  * Note:
 534  * This routine should only be called if the connector was previously
 535  * successfully registered.  If @connector hasn't been registered yet,
 536  * you'll likely see a panic somewhere deep in sysfs code when called.
 537  */
 538 void drm_sysfs_connector_remove(struct drm_connector *connector)
 539 {
 540         if (!connector->kdev)
 541                 return;
 542         DRM_DEBUG("removing \"%s\" from sysfs\n",
 543                   connector->name);
 544
 545         device_unregister(connector->kdev);
 546         connector->kdev = NULL;
 547 }
 548
 549 /**
 550  * drm_sysfs_hotplug_event - generate a DRM uevent
 551  * @dev: DRM device
 552  *
 553  * Send a uevent for the DRM device specified by @dev.  Currently we only
 554  * set HOTPLUG=1 in the uevent environment, but this could be expanded to
 555  * deal with other types of events.
 556  */
 557 void drm_sysfs_hotplug_event(struct drm_device *dev)
 558 {
 559         char *event_string = "HOTPLUG=1";
 560         char *envp[] = { event_string, NULL };
 561
 562         DRM_DEBUG("generating hotplug event\n");
 563
 564         kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
 565 }
 566 EXPORT_SYMBOL(drm_sysfs_hotplug_event);
 567
 568 static void drm_sysfs_release(struct device *dev)
 569 {
 570         kfree(dev);
 571 }
 572
 573 /**
 574  * drm_sysfs_minor_alloc() - Allocate sysfs device for given minor
 575  * @minor: minor to allocate sysfs device for
 576  *
 577  * This allocates a new sysfs device for @minor and returns it. The device is
 578  * not registered nor linked. The caller has to use device_add() and
 579  * device_del() to register and unregister it.
 580  *
 581  * Note that dev_get_drvdata() on the new device will return the minor.
 582  * However, the device does not hold a ref-count to the minor nor to the
 583  * underlying drm_device. This is unproblematic as long as you access the
 584  * private data only in sysfs callbacks. device_del() disables those
 585  * synchronously, so they cannot be called after you cleanup a minor.
 586  */
 587 struct device *drm_sysfs_minor_alloc(struct drm_minor *minor)
 588 {
 589         const char *minor_str;
 590         struct device *kdev;
 591         int r;
 592
 593         if (minor->type == DRM_MINOR_CONTROL)
 594                 minor_str = "controlD%d";
 595         else if (minor->type == DRM_MINOR_RENDER)
 596                 minor_str = "renderD%d";
 597         else
 598                 minor_str = "card%d";
 599
 600         kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
 601         if (!kdev)
 602                 return ERR_PTR(-ENOMEM);
 603
 604         device_initialize(kdev);
 605         kdev->devt = MKDEV(DRM_MAJOR, minor->index);
 606         kdev->class = drm_class;
 607         kdev->type = &drm_sysfs_device_minor;
 608         kdev->parent = minor->dev->dev;
 609         kdev->release = drm_sysfs_release;
 610         dev_set_drvdata(kdev, minor);
 611
 612         r = dev_set_name(kdev, minor_str, minor->index);
 613         if (r < 0)
 614                 goto err_free;
 615
 616         return kdev;
 617
 618 err_free:
 619         put_device(kdev);
 620         return ERR_PTR(r);
 621 }
 622
 623 /**
 624  * drm_class_device_register - Register a struct device in the drm class.
 625  *
 626  * @dev: pointer to struct device to register.
 627  *
 628  * @dev should have all relevant members pre-filled with the exception
 629  * of the class member. In particular, the device_type member must
 630  * be set.
 631  */
 632
 633 int drm_class_device_register(struct device *dev)
 634 {
 635         if (!drm_class || IS_ERR(drm_class))
 636                 return -ENOENT;
 637
 638         dev->class = drm_class;
 639         return device_register(dev);
 640 }
 641 EXPORT_SYMBOL_GPL(drm_class_device_register);
 642
 643 void drm_class_device_unregister(struct device *dev)
 644 {
 645         return device_unregister(dev);
 646 }
 647 EXPORT_SYMBOL_GPL(drm_class_device_unregister);