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