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 struct device_attribute connector_attrs[] = {
 343         __ATTR_RO(status),
 344         __ATTR_RO(enabled),
 345         __ATTR_RO(dpms),
 346         __ATTR_RO(modes),
 347 };
 348
 349 /* These attributes are for both DVI-I connectors and all types of tv-out. */
 350 static struct device_attribute connector_attrs_opt1[] = {
 351         __ATTR_RO(subconnector),
 352         __ATTR_RO(select_subconnector),
 353 };
 354
 355 static struct bin_attribute edid_attr = {
 356         .attr.name = "edid",
 357         .attr.mode = 0444,
 358         .size = 0,
 359         .read = edid_show,
 360 };
 361
 362 /**
 363  * drm_sysfs_connector_add - add a connector to sysfs
 364  * @connector: connector to add
 365  *
 366  * Create a connector device in sysfs, along with its associated connector
 367  * properties (so far, connection status, dpms, mode list & edid) and
 368  * generate a hotplug event so userspace knows there's a new connector
 369  * available.
 370  */
 371 int drm_sysfs_connector_add(struct drm_connector *connector)
 372 {
 373         struct drm_device *dev = connector->dev;
 374         int attr_cnt = 0;
 375         int opt_cnt = 0;
 376         int i;
 377         int ret;
 378
 379         if (connector->kdev)
 380                 return 0;
 381
 382         connector->kdev = device_create(drm_class, dev->primary->kdev,
 383                                         0, connector, "card%d-%s",
 384                                         dev->primary->index, connector->name);
 385         DRM_DEBUG("adding \"%s\" to sysfs\n",
 386                   connector->name);
 387
 388         if (IS_ERR(connector->kdev)) {
 389                 DRM_ERROR("failed to register connector device: %ld\n", PTR_ERR(connector->kdev));
 390                 ret = PTR_ERR(connector->kdev);
 391                 goto out;
 392         }
 393
 394         /* Standard attributes */
 395
 396         for (attr_cnt = 0; attr_cnt < ARRAY_SIZE(connector_attrs); attr_cnt++) {
 397                 ret = device_create_file(connector->kdev, &connector_attrs[attr_cnt]);
 398                 if (ret)
 399                         goto err_out_files;
 400         }
 401
 402         /* Optional attributes */
 403         /*
 404          * In the long run it maybe a good idea to make one set of
 405          * optionals per connector type.
 406          */
 407         switch (connector->connector_type) {
 408                 case DRM_MODE_CONNECTOR_DVII:
 409                 case DRM_MODE_CONNECTOR_Composite:
 410                 case DRM_MODE_CONNECTOR_SVIDEO:
 411                 case DRM_MODE_CONNECTOR_Component:
 412                 case DRM_MODE_CONNECTOR_TV:
 413                         for (opt_cnt = 0; opt_cnt < ARRAY_SIZE(connector_attrs_opt1); opt_cnt++) {
 414                                 ret = device_create_file(connector->kdev, &connector_attrs_opt1[opt_cnt]);
 415                                 if (ret)
 416                                         goto err_out_files;
 417                         }
 418                         break;
 419                 default:
 420                         break;
 421         }
 422
 423         ret = sysfs_create_bin_file(&connector->kdev->kobj, &edid_attr);
 424         if (ret)
 425                 goto err_out_files;
 426
 427         /* Let userspace know we have a new connector */
 428         drm_sysfs_hotplug_event(dev);
 429
 430         return 0;
 431
 432 err_out_files:
 433         for (i = 0; i < opt_cnt; i++)
 434                 device_remove_file(connector->kdev, &connector_attrs_opt1[i]);
 435         for (i = 0; i < attr_cnt; i++)
 436                 device_remove_file(connector->kdev, &connector_attrs[i]);
 437         device_unregister(connector->kdev);
 438
 439 out:
 440         return ret;
 441 }
 442
 443 /**
 444  * drm_sysfs_connector_remove - remove an connector device from sysfs
 445  * @connector: connector to remove
 446  *
 447  * Remove @connector and its associated attributes from sysfs.  Note that
 448  * the device model core will take care of sending the "remove" uevent
 449  * at this time, so we don't need to do it.
 450  *
 451  * Note:
 452  * This routine should only be called if the connector was previously
 453  * successfully registered.  If @connector hasn't been registered yet,
 454  * you'll likely see a panic somewhere deep in sysfs code when called.
 455  */
 456 void drm_sysfs_connector_remove(struct drm_connector *connector)
 457 {
 458         int i;
 459
 460         if (!connector->kdev)
 461                 return;
 462         DRM_DEBUG("removing \"%s\" from sysfs\n",
 463                   connector->name);
 464
 465         for (i = 0; i < ARRAY_SIZE(connector_attrs); i++)
 466                 device_remove_file(connector->kdev, &connector_attrs[i]);
 467         sysfs_remove_bin_file(&connector->kdev->kobj, &edid_attr);
 468         device_unregister(connector->kdev);
 469         connector->kdev = NULL;
 470 }
 471
 472 /**
 473  * drm_sysfs_hotplug_event - generate a DRM uevent
 474  * @dev: DRM device
 475  *
 476  * Send a uevent for the DRM device specified by @dev.  Currently we only
 477  * set HOTPLUG=1 in the uevent environment, but this could be expanded to
 478  * deal with other types of events.
 479  */
 480 void drm_sysfs_hotplug_event(struct drm_device *dev)
 481 {
 482         char *event_string = "HOTPLUG=1";
 483         char *envp[] = { event_string, NULL };
 484
 485         DRM_DEBUG("generating hotplug event\n");
 486
 487         kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
 488 }
 489 EXPORT_SYMBOL(drm_sysfs_hotplug_event);
 490
 491 static void drm_sysfs_release(struct device *dev)
 492 {
 493         kfree(dev);
 494 }
 495
 496 /**
 497  * drm_sysfs_minor_alloc() - Allocate sysfs device for given minor
 498  * @minor: minor to allocate sysfs device for
 499  *
 500  * This allocates a new sysfs device for @minor and returns it. The device is
 501  * not registered nor linked. The caller has to use device_add() and
 502  * device_del() to register and unregister it.
 503  *
 504  * Note that dev_get_drvdata() on the new device will return the minor.
 505  * However, the device does not hold a ref-count to the minor nor to the
 506  * underlying drm_device. This is unproblematic as long as you access the
 507  * private data only in sysfs callbacks. device_del() disables those
 508  * synchronously, so they cannot be called after you cleanup a minor.
 509  */
 510 struct device *drm_sysfs_minor_alloc(struct drm_minor *minor)
 511 {
 512         const char *minor_str;
 513         struct device *kdev;
 514         int r;
 515
 516         if (minor->type == DRM_MINOR_CONTROL)
 517                 minor_str = "controlD%d";
 518         else if (minor->type == DRM_MINOR_RENDER)
 519                 minor_str = "renderD%d";
 520         else
 521                 minor_str = "card%d";
 522
 523         kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
 524         if (!kdev)
 525                 return ERR_PTR(-ENOMEM);
 526
 527         device_initialize(kdev);
 528         kdev->devt = MKDEV(DRM_MAJOR, minor->index);
 529         kdev->class = drm_class;
 530         kdev->type = &drm_sysfs_device_minor;
 531         kdev->parent = minor->dev->dev;
 532         kdev->release = drm_sysfs_release;
 533         dev_set_drvdata(kdev, minor);
 534
 535         r = dev_set_name(kdev, minor_str, minor->index);
 536         if (r < 0)
 537                 goto err_free;
 538
 539         return kdev;
 540
 541 err_free:
 542         put_device(kdev);
 543         return ERR_PTR(r);
 544 }
 545
 546 /**
 547  * drm_class_device_register - Register a struct device in the drm class.
 548  *
 549  * @dev: pointer to struct device to register.
 550  *
 551  * @dev should have all relevant members pre-filled with the exception
 552  * of the class member. In particular, the device_type member must
 553  * be set.
 554  */
 555
 556 int drm_class_device_register(struct device *dev)
 557 {
 558         if (!drm_class || IS_ERR(drm_class))
 559                 return -ENOENT;
 560
 561         dev->class = drm_class;
 562         return device_register(dev);
 563 }
 564 EXPORT_SYMBOL_GPL(drm_class_device_register);
 565
 566 void drm_class_device_unregister(struct device *dev)
 567 {
 568         return device_unregister(dev);
 569 }
 570 EXPORT_SYMBOL_GPL(drm_class_device_unregister);