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