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_show(struct device *device,
 170                            struct device_attribute *attr,
 171                            char *buf)
 172 {
 173         struct drm_connector *connector = to_drm_connector(device);
 174         enum drm_connector_status status;
 175         int ret;
 176
 177         ret = mutex_lock_interruptible(&connector->dev->mode_config.mutex);
 178         if (ret)
 179                 return ret;
 180
 181         status = connector->funcs->detect(connector, true);
 182         mutex_unlock(&connector->dev->mode_config.mutex);
 183
 184         return snprintf(buf, PAGE_SIZE, "%s\n",
 185                         drm_get_connector_status_name(status));
 186 }
 187
 188 static ssize_t dpms_show(struct device *device,
 189                            struct device_attribute *attr,
 190                            char *buf)
 191 {
 192         struct drm_connector *connector = to_drm_connector(device);
 193         struct drm_device *dev = connector->dev;
 194         uint64_t dpms_status;
 195         int ret;
 196
 197         ret = drm_object_property_get_value(&connector->base,
 198                                             dev->mode_config.dpms_property,
 199                                             &dpms_status);
 200         if (ret)
 201                 return 0;
 202
 203         return snprintf(buf, PAGE_SIZE, "%s\n",
 204                         drm_get_dpms_name((int)dpms_status));
 205 }
 206
 207 static ssize_t enabled_show(struct device *device,
 208                             struct device_attribute *attr,
 209                            char *buf)
 210 {
 211         struct drm_connector *connector = to_drm_connector(device);
 212
 213         return snprintf(buf, PAGE_SIZE, "%s\n", connector->encoder ? "enabled" :
 214                         "disabled");
 215 }
 216
 217 static ssize_t edid_show(struct file *filp, struct kobject *kobj,
 218                          struct bin_attribute *attr, char *buf, loff_t off,
 219                          size_t count)
 220 {
 221         struct device *connector_dev = container_of(kobj, struct device, kobj);
 222         struct drm_connector *connector = to_drm_connector(connector_dev);
 223         unsigned char *edid;
 224         size_t size;
 225
 226         if (!connector->edid_blob_ptr)
 227                 return 0;
 228
 229         edid = connector->edid_blob_ptr->data;
 230         size = connector->edid_blob_ptr->length;
 231         if (!edid)
 232                 return 0;
 233
 234         if (off >= size)
 235                 return 0;
 236
 237         if (off + count > size)
 238                 count = size - off;
 239         memcpy(buf, edid + off, count);
 240
 241         return count;
 242 }
 243
 244 static ssize_t modes_show(struct device *device,
 245                            struct device_attribute *attr,
 246                            char *buf)
 247 {
 248         struct drm_connector *connector = to_drm_connector(device);
 249         struct drm_display_mode *mode;
 250         int written = 0;
 251
 252         list_for_each_entry(mode, &connector->modes, head) {
 253                 written += snprintf(buf + written, PAGE_SIZE - written, "%s\n",
 254                                     mode->name);
 255         }
 256
 257         return written;
 258 }
 259
 260 static ssize_t subconnector_show(struct device *device,
 261                            struct device_attribute *attr,
 262                            char *buf)
 263 {
 264         struct drm_connector *connector = to_drm_connector(device);
 265         struct drm_device *dev = connector->dev;
 266         struct drm_property *prop = NULL;
 267         uint64_t subconnector;
 268         int is_tv = 0;
 269         int ret;
 270
 271         switch (connector->connector_type) {
 272                 case DRM_MODE_CONNECTOR_DVII:
 273                         prop = dev->mode_config.dvi_i_subconnector_property;
 274                         break;
 275                 case DRM_MODE_CONNECTOR_Composite:
 276                 case DRM_MODE_CONNECTOR_SVIDEO:
 277                 case DRM_MODE_CONNECTOR_Component:
 278                 case DRM_MODE_CONNECTOR_TV:
 279                         prop = dev->mode_config.tv_subconnector_property;
 280                         is_tv = 1;
 281                         break;
 282                 default:
 283                         DRM_ERROR("Wrong connector type for this property\n");
 284                         return 0;
 285         }
 286
 287         if (!prop) {
 288                 DRM_ERROR("Unable to find subconnector property\n");
 289                 return 0;
 290         }
 291
 292         ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
 293         if (ret)
 294                 return 0;
 295
 296         return snprintf(buf, PAGE_SIZE, "%s", is_tv ?
 297                         drm_get_tv_subconnector_name((int)subconnector) :
 298                         drm_get_dvi_i_subconnector_name((int)subconnector));
 299 }
 300
 301 static ssize_t select_subconnector_show(struct device *device,
 302                            struct device_attribute *attr,
 303                            char *buf)
 304 {
 305         struct drm_connector *connector = to_drm_connector(device);
 306         struct drm_device *dev = connector->dev;
 307         struct drm_property *prop = NULL;
 308         uint64_t subconnector;
 309         int is_tv = 0;
 310         int ret;
 311
 312         switch (connector->connector_type) {
 313                 case DRM_MODE_CONNECTOR_DVII:
 314                         prop = dev->mode_config.dvi_i_select_subconnector_property;
 315                         break;
 316                 case DRM_MODE_CONNECTOR_Composite:
 317                 case DRM_MODE_CONNECTOR_SVIDEO:
 318                 case DRM_MODE_CONNECTOR_Component:
 319                 case DRM_MODE_CONNECTOR_TV:
 320                         prop = dev->mode_config.tv_select_subconnector_property;
 321                         is_tv = 1;
 322                         break;
 323                 default:
 324                         DRM_ERROR("Wrong connector type for this property\n");
 325                         return 0;
 326         }
 327
 328         if (!prop) {
 329                 DRM_ERROR("Unable to find select subconnector property\n");
 330                 return 0;
 331         }
 332
 333         ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
 334         if (ret)
 335                 return 0;
 336
 337         return snprintf(buf, PAGE_SIZE, "%s", is_tv ?
 338                         drm_get_tv_select_name((int)subconnector) :
 339                         drm_get_dvi_i_select_name((int)subconnector));
 340 }
 341
 342 static DEVICE_ATTR_RO(status);
 343 static DEVICE_ATTR_RO(enabled);
 344 static DEVICE_ATTR_RO(dpms);
 345 static DEVICE_ATTR_RO(modes);
 346
 347 static struct attribute *connector_dev_attrs[] = {
 348         &dev_attr_status.attr,
 349         &dev_attr_enabled.attr,
 350         &dev_attr_dpms.attr,
 351         &dev_attr_modes.attr,
 352         NULL
 353 };
 354
 355 /* These attributes are for both DVI-I connectors and all types of tv-out. */
 356 static DEVICE_ATTR_RO(subconnector);
 357 static DEVICE_ATTR_RO(select_subconnector);
 358
 359 static struct attribute *connector_opt_dev_attrs[] = {
 360         &dev_attr_subconnector.attr,
 361         &dev_attr_select_subconnector.attr,
 362         NULL
 363 };
 364
 365 static umode_t connector_opt_dev_is_visible(struct kobject *kobj,
 366                                             struct attribute *attr, int idx)
 367 {
 368         struct device *dev = kobj_to_dev(kobj);
 369         struct drm_connector *connector = to_drm_connector(dev);
 370
 371         /*
 372          * In the long run it maybe a good idea to make one set of
 373          * optionals per connector type.
 374          */
 375         switch (connector->connector_type) {
 376         case DRM_MODE_CONNECTOR_DVII:
 377         case DRM_MODE_CONNECTOR_Composite:
 378         case DRM_MODE_CONNECTOR_SVIDEO:
 379         case DRM_MODE_CONNECTOR_Component:
 380         case DRM_MODE_CONNECTOR_TV:
 381                 return attr->mode;
 382         }
 383
 384         return 0;
 385 }
 386
 387 static struct bin_attribute edid_attr = {
 388         .attr.name = "edid",
 389         .attr.mode = 0444,
 390         .size = 0,
 391         .read = edid_show,
 392 };
 393
 394 static struct bin_attribute *connector_bin_attrs[] = {
 395         &edid_attr,
 396         NULL
 397 };
 398
 399 static const struct attribute_group connector_dev_group = {
 400         .attrs = connector_dev_attrs,
 401         .bin_attrs = connector_bin_attrs,
 402 };
 403
 404 static const struct attribute_group connector_opt_dev_group = {
 405         .attrs = connector_opt_dev_attrs,
 406         .is_visible = connector_opt_dev_is_visible,
 407 };
 408
 409 static const struct attribute_group *connector_dev_groups[] = {
 410         &connector_dev_group,
 411         &connector_opt_dev_group,
 412         NULL
 413 };
 414
 415 /**
 416  * drm_sysfs_connector_add - add a connector to sysfs
 417  * @connector: connector to add
 418  *
 419  * Create a connector device in sysfs, along with its associated connector
 420  * properties (so far, connection status, dpms, mode list & edid) and
 421  * generate a hotplug event so userspace knows there's a new connector
 422  * available.
 423  */
 424 int drm_sysfs_connector_add(struct drm_connector *connector)
 425 {
 426         struct drm_device *dev = connector->dev;
 427
 428         if (connector->kdev)
 429                 return 0;
 430
 431         connector->kdev =
 432                 device_create_with_groups(drm_class, dev->primary->kdev, 0,
 433                                           connector, connector_dev_groups,
 434                                           "card%d-%s", dev->primary->index,
 435                                           connector->name);
 436         DRM_DEBUG("adding \"%s\" to sysfs\n",
 437                   connector->name);
 438
 439         if (IS_ERR(connector->kdev)) {
 440                 DRM_ERROR("failed to register connector device: %ld\n", PTR_ERR(connector->kdev));
 441                 return PTR_ERR(connector->kdev);
 442         }
 443
 444         /* Let userspace know we have a new connector */
 445         drm_sysfs_hotplug_event(dev);
 446
 447         return 0;
 448 }
 449
 450 /**
 451  * drm_sysfs_connector_remove - remove an connector device from sysfs
 452  * @connector: connector to remove
 453  *
 454  * Remove @connector and its associated attributes from sysfs.  Note that
 455  * the device model core will take care of sending the "remove" uevent
 456  * at this time, so we don't need to do it.
 457  *
 458  * Note:
 459  * This routine should only be called if the connector was previously
 460  * successfully registered.  If @connector hasn't been registered yet,
 461  * you'll likely see a panic somewhere deep in sysfs code when called.
 462  */
 463 void drm_sysfs_connector_remove(struct drm_connector *connector)
 464 {
 465         if (!connector->kdev)
 466                 return;
 467         DRM_DEBUG("removing \"%s\" from sysfs\n",
 468                   connector->name);
 469
 470         device_unregister(connector->kdev);
 471         connector->kdev = NULL;
 472 }
 473
 474 /**
 475  * drm_sysfs_hotplug_event - generate a DRM uevent
 476  * @dev: DRM device
 477  *
 478  * Send a uevent for the DRM device specified by @dev.  Currently we only
 479  * set HOTPLUG=1 in the uevent environment, but this could be expanded to
 480  * deal with other types of events.
 481  */
 482 void drm_sysfs_hotplug_event(struct drm_device *dev)
 483 {
 484         char *event_string = "HOTPLUG=1";
 485         char *envp[] = { event_string, NULL };
 486
 487         DRM_DEBUG("generating hotplug event\n");
 488
 489         kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
 490 }
 491 EXPORT_SYMBOL(drm_sysfs_hotplug_event);
 492
 493 static void drm_sysfs_release(struct device *dev)
 494 {
 495         kfree(dev);
 496 }
 497
 498 /**
 499  * drm_sysfs_minor_alloc() - Allocate sysfs device for given minor
 500  * @minor: minor to allocate sysfs device for
 501  *
 502  * This allocates a new sysfs device for @minor and returns it. The device is
 503  * not registered nor linked. The caller has to use device_add() and
 504  * device_del() to register and unregister it.
 505  *
 506  * Note that dev_get_drvdata() on the new device will return the minor.
 507  * However, the device does not hold a ref-count to the minor nor to the
 508  * underlying drm_device. This is unproblematic as long as you access the
 509  * private data only in sysfs callbacks. device_del() disables those
 510  * synchronously, so they cannot be called after you cleanup a minor.
 511  */
 512 struct device *drm_sysfs_minor_alloc(struct drm_minor *minor)
 513 {
 514         const char *minor_str;
 515         struct device *kdev;
 516         int r;
 517
 518         if (minor->type == DRM_MINOR_CONTROL)
 519                 minor_str = "controlD%d";
 520         else if (minor->type == DRM_MINOR_RENDER)
 521                 minor_str = "renderD%d";
 522         else
 523                 minor_str = "card%d";
 524
 525         kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
 526         if (!kdev)
 527                 return ERR_PTR(-ENOMEM);
 528
 529         device_initialize(kdev);
 530         kdev->devt = MKDEV(DRM_MAJOR, minor->index);
 531         kdev->class = drm_class;
 532         kdev->type = &drm_sysfs_device_minor;
 533         kdev->parent = minor->dev->dev;
 534         kdev->release = drm_sysfs_release;
 535         dev_set_drvdata(kdev, minor);
 536
 537         r = dev_set_name(kdev, minor_str, minor->index);
 538         if (r < 0)
 539                 goto err_free;
 540
 541         return kdev;
 542
 543 err_free:
 544         put_device(kdev);
 545         return ERR_PTR(r);
 546 }
 547
 548 /**
 549  * drm_class_device_register - Register a struct device in the drm class.
 550  *
 551  * @dev: pointer to struct device to register.
 552  *
 553  * @dev should have all relevant members pre-filled with the exception
 554  * of the class member. In particular, the device_type member must
 555  * be set.
 556  */
 557
 558 int drm_class_device_register(struct device *dev)
 559 {
 560         if (!drm_class || IS_ERR(drm_class))
 561                 return -ENOENT;
 562
 563         dev->class = drm_class;
 564         return device_register(dev);
 565 }
 566 EXPORT_SYMBOL_GPL(drm_class_device_register);
 567
 568 void drm_class_device_unregister(struct device *dev)
 569 {
 570         return device_unregister(dev);
 571 }
 572 EXPORT_SYMBOL_GPL(drm_class_device_unregister);