aboutsummaryrefslogtreecommitdiff
path: root/include/drm/drm_drv.h
blob: 412e83a4d3dba895355b6813f0e9410a7eeecef4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
/*
 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 * Copyright (c) 2009-2010, Code Aurora Forum.
 * Copyright 2016 Intel Corp.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef _DRM_DRV_H_
#define _DRM_DRV_H_

#include <linux/list.h>
#include <linux/irqreturn.h>

#include <drm/drm_device.h>

struct drm_file;
struct drm_gem_object;
struct drm_master;
struct drm_minor;
struct dma_buf_attachment;
struct drm_display_mode;
struct drm_mode_create_dumb;

/* driver capabilities and requirements mask */
#define DRIVER_USE_AGP			0x1
#define DRIVER_LEGACY			0x2
#define DRIVER_PCI_DMA			0x8
#define DRIVER_SG			0x10
#define DRIVER_HAVE_DMA			0x20
#define DRIVER_HAVE_IRQ			0x40
#define DRIVER_IRQ_SHARED		0x80
#define DRIVER_GEM			0x1000
#define DRIVER_MODESET			0x2000
#define DRIVER_PRIME			0x4000
#define DRIVER_RENDER			0x8000
#define DRIVER_ATOMIC			0x10000
#define DRIVER_KMS_LEGACY_CONTEXT	0x20000
#define DRIVER_SYNCOBJ                  0x40000

/**
 * struct drm_driver - DRM driver structure
 *
 * This structure represent the common code for a family of cards. There will
 * one drm_device for each card present in this family. It contains lots of
 * vfunc entries, and a pile of those probably should be moved to more
 * appropriate places like &drm_mode_config_funcs or into a new operations
 * structure for GEM drivers.
 */
struct drm_driver {
	/**
	 * @load:
	 *
	 * Backward-compatible driver callback to complete
	 * initialization steps after the driver is registered.  For
	 * this reason, may suffer from race conditions and its use is
	 * deprecated for new drivers.  It is therefore only supported
	 * for existing drivers not yet converted to the new scheme.
	 * See drm_dev_init() and drm_dev_register() for proper and
	 * race-free way to set up a &struct drm_device.
	 *
	 * This is deprecated, do not use!
	 *
	 * Returns:
	 *
	 * Zero on success, non-zero value on failure.
	 */
	int (*load) (struct drm_device *, unsigned long flags);

	/**
	 * @open:
	 *
	 * Driver callback when a new &struct drm_file is opened. Useful for
	 * setting up driver-private data structures like buffer allocators,
	 * execution contexts or similar things. Such driver-private resources
	 * must be released again in @postclose.
	 *
	 * Since the display/modeset side of DRM can only be owned by exactly
	 * one &struct drm_file (see &drm_file.is_master and &drm_device.master)
	 * there should never be a need to set up any modeset related resources
	 * in this callback. Doing so would be a driver design bug.
	 *
	 * Returns:
	 *
	 * 0 on success, a negative error code on failure, which will be
	 * promoted to userspace as the result of the open() system call.
	 */
	int (*open) (struct drm_device *, struct drm_file *);

	/**
	 * @postclose:
	 *
	 * One of the driver callbacks when a new &struct drm_file is closed.
	 * Useful for tearing down driver-private data structures allocated in
	 * @open like buffer allocators, execution contexts or similar things.
	 *
	 * Since the display/modeset side of DRM can only be owned by exactly
	 * one &struct drm_file (see &drm_file.is_master and &drm_device.master)
	 * there should never be a need to tear down any modeset related
	 * resources in this callback. Doing so would be a driver design bug.
	 */
	void (*postclose) (struct drm_device *, struct drm_file *);

	/**
	 * @lastclose:
	 *
	 * Called when the last &struct drm_file has been closed and there's
	 * currently no userspace client for the &struct drm_device.
	 *
	 * Modern drivers should only use this to force-restore the fbdev
	 * framebuffer using drm_fb_helper_restore_fbdev_mode_unlocked().
	 * Anything else would indicate there's something seriously wrong.
	 * Modern drivers can also use this to execute delayed power switching
	 * state changes, e.g. in conjunction with the :ref:`vga_switcheroo`
	 * infrastructure.
	 *
	 * This is called after @postclose hook has been called.
	 *
	 * NOTE:
	 *
	 * All legacy drivers use this callback to de-initialize the hardware.
	 * This is purely because of the shadow-attach model, where the DRM
	 * kernel driver does not really own the hardware. Instead ownershipe is
	 * handled with the help of userspace through an inheritedly racy dance
	 * to set/unset the VT into raw mode.
	 *
	 * Legacy drivers initialize the hardware in the @firstopen callback,
	 * which isn't even called for modern drivers.
	 */
	void (*lastclose) (struct drm_device *);

	/**
	 * @unload:
	 *
	 * Reverse the effects of the driver load callback.  Ideally,
	 * the clean up performed by the driver should happen in the
	 * reverse order of the initialization.  Similarly to the load
	 * hook, this handler is deprecated and its usage should be
	 * dropped in favor of an open-coded teardown function at the
	 * driver layer.  See drm_dev_unregister() and drm_dev_put()
	 * for the proper way to remove a &struct drm_device.
	 *
	 * The unload() hook is called right after unregistering
	 * the device.
	 *
	 */
	void (*unload) (struct drm_device *);

	/**
	 * @release:
	 *
	 * Optional callback for destroying device data after the final
	 * reference is released, i.e. the device is being destroyed. Drivers
	 * using this callback are responsible for calling drm_dev_fini()
	 * to finalize the device and then freeing the struct themselves.
	 */
	void (*release) (struct drm_device *);

	/**
	 * @get_vblank_counter:
	 *
	 * Driver callback for fetching a raw hardware vblank counter for the
	 * CRTC specified with the pipe argument.  If a device doesn't have a
	 * hardware counter, the driver can simply leave the hook as NULL.
	 * The DRM core will account for missed vblank events while interrupts
	 * where disabled based on system timestamps.
	 *
	 * Wraparound handling and loss of events due to modesetting is dealt
	 * with in the DRM core code, as long as drivers call
	 * drm_crtc_vblank_off() and drm_crtc_vblank_on() when disabling or
	 * enabling a CRTC.
	 *
	 * This is deprecated and should not be used by new drivers.
	 * Use &drm_crtc_funcs.get_vblank_counter instead.
	 *
	 * Returns:
	 *
	 * Raw vblank counter value.
	 */
	u32 (*get_vblank_counter) (struct drm_device *dev, unsigned int pipe);

	/**
	 * @enable_vblank:
	 *
	 * Enable vblank interrupts for the CRTC specified with the pipe
	 * argument.
	 *
	 * This is deprecated and should not be used by new drivers.
	 * Use &drm_crtc_funcs.enable_vblank instead.
	 *
	 * Returns:
	 *
	 * Zero on success, appropriate errno if the given @crtc's vblank
	 * interrupt cannot be enabled.
	 */
	int (*enable_vblank) (struct drm_device *dev, unsigned int pipe);

	/**
	 * @disable_vblank:
	 *
	 * Disable vblank interrupts for the CRTC specified with the pipe
	 * argument.
	 *
	 * This is deprecated and should not be used by new drivers.
	 * Use &drm_crtc_funcs.disable_vblank instead.
	 */
	void (*disable_vblank) (struct drm_device *dev, unsigned int pipe);

	/**
	 * @get_scanout_position:
	 *
	 * Called by vblank timestamping code.
	 *
	 * Returns the current display scanout position from a crtc, and an
	 * optional accurate ktime_get() timestamp of when position was
	 * measured. Note that this is a helper callback which is only used if a
	 * driver uses drm_calc_vbltimestamp_from_scanoutpos() for the
	 * @get_vblank_timestamp callback.
	 *
	 * Parameters:
	 *
	 * dev:
	 *     DRM device.
	 * pipe:
	 *     Id of the crtc to query.
	 * in_vblank_irq:
	 *     True when called from drm_crtc_handle_vblank().  Some drivers
	 *     need to apply some workarounds for gpu-specific vblank irq quirks
	 *     if flag is set.
	 * vpos:
	 *     Target location for current vertical scanout position.
	 * hpos:
	 *     Target location for current horizontal scanout position.
	 * stime:
	 *     Target location for timestamp taken immediately before
	 *     scanout position query. Can be NULL to skip timestamp.
	 * etime:
	 *     Target location for timestamp taken immediately after
	 *     scanout position query. Can be NULL to skip timestamp.
	 * mode:
	 *     Current display timings.
	 *
	 * Returns vpos as a positive number while in active scanout area.
	 * Returns vpos as a negative number inside vblank, counting the number
	 * of scanlines to go until end of vblank, e.g., -1 means "one scanline
	 * until start of active scanout / end of vblank."
	 *
	 * Returns:
	 *
	 * True on success, false if a reliable scanout position counter could
	 * not be read out.
	 *
	 * FIXME:
	 *
	 * Since this is a helper to implement @get_vblank_timestamp, we should
	 * move it to &struct drm_crtc_helper_funcs, like all the other
	 * helper-internal hooks.
	 */
	bool (*get_scanout_position) (struct drm_device *dev, unsigned int pipe,
				      bool in_vblank_irq, int *vpos, int *hpos,
				      ktime_t *stime, ktime_t *etime,
				      const struct drm_display_mode *mode);

	/**
	 * @get_vblank_timestamp:
	 *
	 * Called by drm_get_last_vbltimestamp(). Should return a precise
	 * timestamp when the most recent VBLANK interval ended or will end.
	 *
	 * Specifically, the timestamp in @vblank_time should correspond as
	 * closely as possible to the time when the first video scanline of
	 * the video frame after the end of VBLANK will start scanning out,
	 * the time immediately after end of the VBLANK interval. If the
	 * @crtc is currently inside VBLANK, this will be a time in the future.
	 * If the @crtc is currently scanning out a frame, this will be the
	 * past start time of the current scanout. This is meant to adhere
	 * to the OpenML OML_sync_control extension specification.
	 *
	 * Paramters:
	 *
	 * dev:
	 *     dev DRM device handle.
	 * pipe:
	 *     crtc for which timestamp should be returned.
	 * max_error:
	 *     Maximum allowable timestamp error in nanoseconds.
	 *     Implementation should strive to provide timestamp
	 *     with an error of at most max_error nanoseconds.
	 *     Returns true upper bound on error for timestamp.
	 * vblank_time:
	 *     Target location for returned vblank timestamp.
	 * in_vblank_irq:
	 *     True when called from drm_crtc_handle_vblank().  Some drivers
	 *     need to apply some workarounds for gpu-specific vblank irq quirks
	 *     if flag is set.
	 *
	 * Returns:
	 *
	 * True on success, false on failure, which means the core should
	 * fallback to a simple timestamp taken in drm_crtc_handle_vblank().
	 *
	 * FIXME:
	 *
	 * We should move this hook to &struct drm_crtc_funcs like all the other
	 * vblank hooks.
	 */
	bool (*get_vblank_timestamp) (struct drm_device *dev, unsigned int pipe,
				     int *max_error,
				     ktime_t *vblank_time,
				     bool in_vblank_irq);

	/**
	 * @irq_handler:
	 *
	 * Interrupt handler called when using drm_irq_install(). Not used by
	 * drivers which implement their own interrupt handling.
	 */
	irqreturn_t(*irq_handler) (int irq, void *arg);

	/**
	 * @irq_preinstall:
	 *
	 * Optional callback used by drm_irq_install() which is called before
	 * the interrupt handler is registered. This should be used to clear out
	 * any pending interrupts (from e.g. firmware based drives) and reset
	 * the interrupt handling registers.
	 */
	void (*irq_preinstall) (struct drm_device *dev);

	/**
	 * @irq_postinstall:
	 *
	 * Optional callback used by drm_irq_install() which is called after
	 * the interrupt handler is registered. This should be used to enable
	 * interrupt generation in the hardware.
	 */
	int (*irq_postinstall) (struct drm_device *dev);

	/**
	 * @irq_uninstall:
	 *
	 * Optional callback used by drm_irq_uninstall() which is called before
	 * the interrupt handler is unregistered. This should be used to disable
	 * interrupt generation in the hardware.
	 */
	void (*irq_uninstall) (struct drm_device *dev);

	/**
	 * @master_create:
	 *
	 * Called whenever a new master is created. Only used by vmwgfx.
	 */
	int (*master_create)(struct drm_device *dev, struct drm_master *master);

	/**
	 * @master_destroy:
	 *
	 * Called whenever a master is destroyed. Only used by vmwgfx.
	 */
	void (*master_destroy)(struct drm_device *dev, struct drm_master *master);

	/**
	 * @master_set:
	 *
	 * Called whenever the minor master is set. Only used by vmwgfx.
	 */
	int (*master_set)(struct drm_device *dev, struct drm_file *file_priv,
			  bool from_open);
	/**
	 * @master_drop:
	 *
	 * Called whenever the minor master is dropped. Only used by vmwgfx.
	 */
	void (*master_drop)(struct drm_device *dev, struct drm_file *file_priv);

	/**
	 * @debugfs_init:
	 *
	 * Allows drivers to create driver-specific debugfs files.
	 */
	int (*debugfs_init)(struct drm_minor *minor);

	/**
	 * @gem_free_object: deconstructor for drm_gem_objects
	 *
	 * This is deprecated and should not be used by new drivers. Use
	 * @gem_free_object_unlocked instead.
	 */
	void (*gem_free_object) (struct drm_gem_object *obj);

	/**
	 * @gem_free_object_unlocked: deconstructor for drm_gem_objects
	 *
	 * This is for drivers which are not encumbered with &drm_device.struct_mutex
	 * legacy locking schemes. Use this hook instead of @gem_free_object.
	 */
	void (*gem_free_object_unlocked) (struct drm_gem_object *obj);

	/**
	 * @gem_open_object:
	 *
	 * Driver hook called upon gem handle creation
	 */
	int (*gem_open_object) (struct drm_gem_object *, struct drm_file *);

	/**
	 * @gem_close_object:
	 *
	 * Driver hook called upon gem handle release
	 */
	void (*gem_close_object) (struct drm_gem_object *, struct drm_file *);

	/**
	 * @gem_create_object: constructor for gem objects
	 *
	 * Hook for allocating the GEM object struct, for use by core
	 * helpers.
	 */
	struct drm_gem_object *(*gem_create_object)(struct drm_device *dev,
						    size_t size);

	/* prime: */
	/**
	 * @prime_handle_to_fd:
	 *
	 * export handle -> fd (see drm_gem_prime_handle_to_fd() helper)
	 */
	int (*prime_handle_to_fd)(struct drm_device *dev, struct drm_file *file_priv,
				uint32_t handle, uint32_t flags, int *prime_fd);
	/**
	 * @prime_fd_to_handle:
	 *
	 * import fd -> handle (see drm_gem_prime_fd_to_handle() helper)
	 */
	int (*prime_fd_to_handle)(struct drm_device *dev, struct drm_file *file_priv,
				int prime_fd, uint32_t *handle);
	/**
	 * @gem_prime_export:
	 *
	 * export GEM -> dmabuf
	 */
	struct dma_buf * (*gem_prime_export)(struct drm_device *dev,
				struct drm_gem_object *obj, int flags);
	/**
	 * @gem_prime_import:
	 *
	 * import dmabuf -> GEM
	 */
	struct drm_gem_object * (*gem_prime_import)(struct drm_device *dev,
				struct dma_buf *dma_buf);
	int (*gem_prime_pin)(struct drm_gem_object *obj);
	void (*gem_prime_unpin)(struct drm_gem_object *obj);
	struct reservation_object * (*gem_prime_res_obj)(
				struct drm_gem_object *obj);
	struct sg_table *(*gem_prime_get_sg_table)(struct drm_gem_object *obj);
	struct drm_gem_object *(*gem_prime_import_sg_table)(
				struct drm_device *dev,
				struct dma_buf_attachment *attach,
				struct sg_table *sgt);
	void *(*gem_prime_vmap)(struct drm_gem_object *obj);
	void (*gem_prime_vunmap)(struct drm_gem_object *obj, void *vaddr);
	int (*gem_prime_mmap)(struct drm_gem_object *obj,
				struct vm_area_struct *vma);

	/**
	 * @dumb_create:
	 *
	 * This creates a new dumb buffer in the driver's backing storage manager (GEM,
	 * TTM or something else entirely) and returns the resulting buffer handle. This
	 * handle can then be wrapped up into a framebuffer modeset object.
	 *
	 * Note that userspace is not allowed to use such objects for render
	 * acceleration - drivers must create their own private ioctls for such a use
	 * case.
	 *
	 * Width, height and depth are specified in the &drm_mode_create_dumb
	 * argument. The callback needs to fill the handle, pitch and size for
	 * the created buffer.
	 *
	 * Called by the user via ioctl.
	 *
	 * Returns:
	 *
	 * Zero on success, negative errno on failure.
	 */
	int (*dumb_create)(struct drm_file *file_priv,
			   struct drm_device *dev,
			   struct drm_mode_create_dumb *args);
	/**
	 * @dumb_map_offset:
	 *
	 * Allocate an offset in the drm device node's address space to be able to
	 * memory map a dumb buffer. GEM-based drivers must use
	 * drm_gem_create_mmap_offset() to implement this.
	 *
	 * Called by the user via ioctl.
	 *
	 * Returns:
	 *
	 * Zero on success, negative errno on failure.
	 */
	int (*dumb_map_offset)(struct drm_file *file_priv,
			       struct drm_device *dev, uint32_t handle,
			       uint64_t *offset);
	/**
	 * @dumb_destroy:
	 *
	 * This destroys the userspace handle for the given dumb backing storage buffer.
	 * Since buffer objects must be reference counted in the kernel a buffer object
	 * won't be immediately freed if a framebuffer modeset object still uses it.
	 *
	 * Called by the user via ioctl.
	 *
	 * Returns:
	 *
	 * Zero on success, negative errno on failure.
	 */
	int (*dumb_destroy)(struct drm_file *file_priv,
			    struct drm_device *dev,
			    uint32_t handle);

	/**
	 * @gem_vm_ops: Driver private ops for this object
	 */
	const struct vm_operations_struct *gem_vm_ops;

	/** @major: driver major number */
	int major;
	/** @minor: driver minor number */
	int minor;
	/** @patchlevel: driver patch level */
	int patchlevel;
	/** @name: driver name */
	char *name;
	/** @desc: driver description */
	char *desc;
	/** @date: driver date */
	char *date;

	/** @driver_features: driver features */
	u32 driver_features;

	/**
	 * @ioctls:
	 *
	 * Array of driver-private IOCTL description entries. See the chapter on
	 * :ref:`IOCTL support in the userland interfaces
	 * chapter<drm_driver_ioctl>` for the full details.
	 */

	const struct drm_ioctl_desc *ioctls;
	/** @num_ioctls: Number of entries in @ioctls. */
	int num_ioctls;

	/**
	 * @fops:
	 *
	 * File operations for the DRM device node. See the discussion in
	 * :ref:`file operations<drm_driver_fops>` for in-depth coverage and
	 * some examples.
	 */
	const struct file_operations *fops;

	/* Everything below here is for legacy driver, never use! */
	/* private: */

	/* List of devices hanging off this driver with stealth attach. */
	struct list_head legacy_dev_list;
	int (*firstopen) (struct drm_device *);
	void (*preclose) (struct drm_device *, struct drm_file *file_priv);
	int (*dma_ioctl) (struct drm_device *dev, void *data, struct drm_file *file_priv);
	int (*dma_quiescent) (struct drm_device *);
	int (*context_dtor) (struct drm_device *dev, int context);
	int dev_priv_size;
};

__printf(6, 7)
void drm_dev_printk(const struct device *dev, const char *level,
		    unsigned int category, const char *function_name,
		    const char *prefix, const char *format, ...);
__printf(3, 4)
void drm_printk(const char *level, unsigned int category,
		const char *format, ...);
extern unsigned int drm_debug;

int drm_dev_init(struct drm_device *dev,
		 struct drm_driver *driver,
		 struct device *parent);
void drm_dev_fini(struct drm_device *dev);

struct drm_device *drm_dev_alloc(struct drm_driver *driver,
				 struct device *parent);
int drm_dev_register(struct drm_device *dev, unsigned long flags);
void drm_dev_unregister(struct drm_device *dev);

void drm_dev_get(struct drm_device *dev);
void drm_dev_put(struct drm_device *dev);
void drm_dev_unref(struct drm_device *dev);
void drm_put_dev(struct drm_device *dev);
void drm_dev_unplug(struct drm_device *dev);

/**
 * drm_dev_is_unplugged - is a DRM device unplugged
 * @dev: DRM device
 *
 * This function can be called to check whether a hotpluggable is unplugged.
 * Unplugging itself is singalled through drm_dev_unplug(). If a device is
 * unplugged, these two functions guarantee that any store before calling
 * drm_dev_unplug() is visible to callers of this function after it completes
 */
static inline int drm_dev_is_unplugged(struct drm_device *dev)
{
	int ret = atomic_read(&dev->unplugged);
	smp_rmb();
	return ret;
}


int drm_dev_set_unique(struct drm_device *dev, const char *name);


#endif