xref: /openbmc/linux/include/drm/drm_drv.h (revision 2359ccdd)
1 /*
2  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
3  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
4  * Copyright (c) 2009-2010, Code Aurora Forum.
5  * Copyright 2016 Intel Corp.
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a
8  * copy of this software and associated documentation files (the "Software"),
9  * to deal in the Software without restriction, including without limitation
10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11  * and/or sell copies of the Software, and to permit persons to whom the
12  * Software is furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice (including the next
15  * paragraph) shall be included in all copies or substantial portions of the
16  * Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
21  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
22  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
23  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
24  * OTHER DEALINGS IN THE SOFTWARE.
25  */
26 
27 #ifndef _DRM_DRV_H_
28 #define _DRM_DRV_H_
29 
30 #include <linux/list.h>
31 #include <linux/irqreturn.h>
32 
33 #include <drm/drm_device.h>
34 
35 struct drm_file;
36 struct drm_gem_object;
37 struct drm_master;
38 struct drm_minor;
39 struct dma_buf_attachment;
40 struct drm_display_mode;
41 struct drm_mode_create_dumb;
42 struct drm_printer;
43 
44 /* driver capabilities and requirements mask */
45 #define DRIVER_USE_AGP			0x1
46 #define DRIVER_LEGACY			0x2
47 #define DRIVER_PCI_DMA			0x8
48 #define DRIVER_SG			0x10
49 #define DRIVER_HAVE_DMA			0x20
50 #define DRIVER_HAVE_IRQ			0x40
51 #define DRIVER_IRQ_SHARED		0x80
52 #define DRIVER_GEM			0x1000
53 #define DRIVER_MODESET			0x2000
54 #define DRIVER_PRIME			0x4000
55 #define DRIVER_RENDER			0x8000
56 #define DRIVER_ATOMIC			0x10000
57 #define DRIVER_KMS_LEGACY_CONTEXT	0x20000
58 #define DRIVER_SYNCOBJ                  0x40000
59 #define DRIVER_PREFER_XBGR_30BPP        0x80000
60 
61 /**
62  * struct drm_driver - DRM driver structure
63  *
64  * This structure represent the common code for a family of cards. There will
65  * one drm_device for each card present in this family. It contains lots of
66  * vfunc entries, and a pile of those probably should be moved to more
67  * appropriate places like &drm_mode_config_funcs or into a new operations
68  * structure for GEM drivers.
69  */
70 struct drm_driver {
71 	/**
72 	 * @load:
73 	 *
74 	 * Backward-compatible driver callback to complete
75 	 * initialization steps after the driver is registered.  For
76 	 * this reason, may suffer from race conditions and its use is
77 	 * deprecated for new drivers.  It is therefore only supported
78 	 * for existing drivers not yet converted to the new scheme.
79 	 * See drm_dev_init() and drm_dev_register() for proper and
80 	 * race-free way to set up a &struct drm_device.
81 	 *
82 	 * This is deprecated, do not use!
83 	 *
84 	 * Returns:
85 	 *
86 	 * Zero on success, non-zero value on failure.
87 	 */
88 	int (*load) (struct drm_device *, unsigned long flags);
89 
90 	/**
91 	 * @open:
92 	 *
93 	 * Driver callback when a new &struct drm_file is opened. Useful for
94 	 * setting up driver-private data structures like buffer allocators,
95 	 * execution contexts or similar things. Such driver-private resources
96 	 * must be released again in @postclose.
97 	 *
98 	 * Since the display/modeset side of DRM can only be owned by exactly
99 	 * one &struct drm_file (see &drm_file.is_master and &drm_device.master)
100 	 * there should never be a need to set up any modeset related resources
101 	 * in this callback. Doing so would be a driver design bug.
102 	 *
103 	 * Returns:
104 	 *
105 	 * 0 on success, a negative error code on failure, which will be
106 	 * promoted to userspace as the result of the open() system call.
107 	 */
108 	int (*open) (struct drm_device *, struct drm_file *);
109 
110 	/**
111 	 * @postclose:
112 	 *
113 	 * One of the driver callbacks when a new &struct drm_file is closed.
114 	 * Useful for tearing down driver-private data structures allocated in
115 	 * @open like buffer allocators, execution contexts or similar things.
116 	 *
117 	 * Since the display/modeset side of DRM can only be owned by exactly
118 	 * one &struct drm_file (see &drm_file.is_master and &drm_device.master)
119 	 * there should never be a need to tear down any modeset related
120 	 * resources in this callback. Doing so would be a driver design bug.
121 	 */
122 	void (*postclose) (struct drm_device *, struct drm_file *);
123 
124 	/**
125 	 * @lastclose:
126 	 *
127 	 * Called when the last &struct drm_file has been closed and there's
128 	 * currently no userspace client for the &struct drm_device.
129 	 *
130 	 * Modern drivers should only use this to force-restore the fbdev
131 	 * framebuffer using drm_fb_helper_restore_fbdev_mode_unlocked().
132 	 * Anything else would indicate there's something seriously wrong.
133 	 * Modern drivers can also use this to execute delayed power switching
134 	 * state changes, e.g. in conjunction with the :ref:`vga_switcheroo`
135 	 * infrastructure.
136 	 *
137 	 * This is called after @postclose hook has been called.
138 	 *
139 	 * NOTE:
140 	 *
141 	 * All legacy drivers use this callback to de-initialize the hardware.
142 	 * This is purely because of the shadow-attach model, where the DRM
143 	 * kernel driver does not really own the hardware. Instead ownershipe is
144 	 * handled with the help of userspace through an inheritedly racy dance
145 	 * to set/unset the VT into raw mode.
146 	 *
147 	 * Legacy drivers initialize the hardware in the @firstopen callback,
148 	 * which isn't even called for modern drivers.
149 	 */
150 	void (*lastclose) (struct drm_device *);
151 
152 	/**
153 	 * @unload:
154 	 *
155 	 * Reverse the effects of the driver load callback.  Ideally,
156 	 * the clean up performed by the driver should happen in the
157 	 * reverse order of the initialization.  Similarly to the load
158 	 * hook, this handler is deprecated and its usage should be
159 	 * dropped in favor of an open-coded teardown function at the
160 	 * driver layer.  See drm_dev_unregister() and drm_dev_put()
161 	 * for the proper way to remove a &struct drm_device.
162 	 *
163 	 * The unload() hook is called right after unregistering
164 	 * the device.
165 	 *
166 	 */
167 	void (*unload) (struct drm_device *);
168 
169 	/**
170 	 * @release:
171 	 *
172 	 * Optional callback for destroying device data after the final
173 	 * reference is released, i.e. the device is being destroyed. Drivers
174 	 * using this callback are responsible for calling drm_dev_fini()
175 	 * to finalize the device and then freeing the struct themselves.
176 	 */
177 	void (*release) (struct drm_device *);
178 
179 	/**
180 	 * @get_vblank_counter:
181 	 *
182 	 * Driver callback for fetching a raw hardware vblank counter for the
183 	 * CRTC specified with the pipe argument.  If a device doesn't have a
184 	 * hardware counter, the driver can simply leave the hook as NULL.
185 	 * The DRM core will account for missed vblank events while interrupts
186 	 * where disabled based on system timestamps.
187 	 *
188 	 * Wraparound handling and loss of events due to modesetting is dealt
189 	 * with in the DRM core code, as long as drivers call
190 	 * drm_crtc_vblank_off() and drm_crtc_vblank_on() when disabling or
191 	 * enabling a CRTC.
192 	 *
193 	 * This is deprecated and should not be used by new drivers.
194 	 * Use &drm_crtc_funcs.get_vblank_counter instead.
195 	 *
196 	 * Returns:
197 	 *
198 	 * Raw vblank counter value.
199 	 */
200 	u32 (*get_vblank_counter) (struct drm_device *dev, unsigned int pipe);
201 
202 	/**
203 	 * @enable_vblank:
204 	 *
205 	 * Enable vblank interrupts for the CRTC specified with the pipe
206 	 * argument.
207 	 *
208 	 * This is deprecated and should not be used by new drivers.
209 	 * Use &drm_crtc_funcs.enable_vblank instead.
210 	 *
211 	 * Returns:
212 	 *
213 	 * Zero on success, appropriate errno if the given @crtc's vblank
214 	 * interrupt cannot be enabled.
215 	 */
216 	int (*enable_vblank) (struct drm_device *dev, unsigned int pipe);
217 
218 	/**
219 	 * @disable_vblank:
220 	 *
221 	 * Disable vblank interrupts for the CRTC specified with the pipe
222 	 * argument.
223 	 *
224 	 * This is deprecated and should not be used by new drivers.
225 	 * Use &drm_crtc_funcs.disable_vblank instead.
226 	 */
227 	void (*disable_vblank) (struct drm_device *dev, unsigned int pipe);
228 
229 	/**
230 	 * @get_scanout_position:
231 	 *
232 	 * Called by vblank timestamping code.
233 	 *
234 	 * Returns the current display scanout position from a crtc, and an
235 	 * optional accurate ktime_get() timestamp of when position was
236 	 * measured. Note that this is a helper callback which is only used if a
237 	 * driver uses drm_calc_vbltimestamp_from_scanoutpos() for the
238 	 * @get_vblank_timestamp callback.
239 	 *
240 	 * Parameters:
241 	 *
242 	 * dev:
243 	 *     DRM device.
244 	 * pipe:
245 	 *     Id of the crtc to query.
246 	 * in_vblank_irq:
247 	 *     True when called from drm_crtc_handle_vblank().  Some drivers
248 	 *     need to apply some workarounds for gpu-specific vblank irq quirks
249 	 *     if flag is set.
250 	 * vpos:
251 	 *     Target location for current vertical scanout position.
252 	 * hpos:
253 	 *     Target location for current horizontal scanout position.
254 	 * stime:
255 	 *     Target location for timestamp taken immediately before
256 	 *     scanout position query. Can be NULL to skip timestamp.
257 	 * etime:
258 	 *     Target location for timestamp taken immediately after
259 	 *     scanout position query. Can be NULL to skip timestamp.
260 	 * mode:
261 	 *     Current display timings.
262 	 *
263 	 * Returns vpos as a positive number while in active scanout area.
264 	 * Returns vpos as a negative number inside vblank, counting the number
265 	 * of scanlines to go until end of vblank, e.g., -1 means "one scanline
266 	 * until start of active scanout / end of vblank."
267 	 *
268 	 * Returns:
269 	 *
270 	 * True on success, false if a reliable scanout position counter could
271 	 * not be read out.
272 	 *
273 	 * FIXME:
274 	 *
275 	 * Since this is a helper to implement @get_vblank_timestamp, we should
276 	 * move it to &struct drm_crtc_helper_funcs, like all the other
277 	 * helper-internal hooks.
278 	 */
279 	bool (*get_scanout_position) (struct drm_device *dev, unsigned int pipe,
280 				      bool in_vblank_irq, int *vpos, int *hpos,
281 				      ktime_t *stime, ktime_t *etime,
282 				      const struct drm_display_mode *mode);
283 
284 	/**
285 	 * @get_vblank_timestamp:
286 	 *
287 	 * Called by drm_get_last_vbltimestamp(). Should return a precise
288 	 * timestamp when the most recent VBLANK interval ended or will end.
289 	 *
290 	 * Specifically, the timestamp in @vblank_time should correspond as
291 	 * closely as possible to the time when the first video scanline of
292 	 * the video frame after the end of VBLANK will start scanning out,
293 	 * the time immediately after end of the VBLANK interval. If the
294 	 * @crtc is currently inside VBLANK, this will be a time in the future.
295 	 * If the @crtc is currently scanning out a frame, this will be the
296 	 * past start time of the current scanout. This is meant to adhere
297 	 * to the OpenML OML_sync_control extension specification.
298 	 *
299 	 * Paramters:
300 	 *
301 	 * dev:
302 	 *     dev DRM device handle.
303 	 * pipe:
304 	 *     crtc for which timestamp should be returned.
305 	 * max_error:
306 	 *     Maximum allowable timestamp error in nanoseconds.
307 	 *     Implementation should strive to provide timestamp
308 	 *     with an error of at most max_error nanoseconds.
309 	 *     Returns true upper bound on error for timestamp.
310 	 * vblank_time:
311 	 *     Target location for returned vblank timestamp.
312 	 * in_vblank_irq:
313 	 *     True when called from drm_crtc_handle_vblank().  Some drivers
314 	 *     need to apply some workarounds for gpu-specific vblank irq quirks
315 	 *     if flag is set.
316 	 *
317 	 * Returns:
318 	 *
319 	 * True on success, false on failure, which means the core should
320 	 * fallback to a simple timestamp taken in drm_crtc_handle_vblank().
321 	 *
322 	 * FIXME:
323 	 *
324 	 * We should move this hook to &struct drm_crtc_funcs like all the other
325 	 * vblank hooks.
326 	 */
327 	bool (*get_vblank_timestamp) (struct drm_device *dev, unsigned int pipe,
328 				     int *max_error,
329 				     ktime_t *vblank_time,
330 				     bool in_vblank_irq);
331 
332 	/**
333 	 * @irq_handler:
334 	 *
335 	 * Interrupt handler called when using drm_irq_install(). Not used by
336 	 * drivers which implement their own interrupt handling.
337 	 */
338 	irqreturn_t(*irq_handler) (int irq, void *arg);
339 
340 	/**
341 	 * @irq_preinstall:
342 	 *
343 	 * Optional callback used by drm_irq_install() which is called before
344 	 * the interrupt handler is registered. This should be used to clear out
345 	 * any pending interrupts (from e.g. firmware based drives) and reset
346 	 * the interrupt handling registers.
347 	 */
348 	void (*irq_preinstall) (struct drm_device *dev);
349 
350 	/**
351 	 * @irq_postinstall:
352 	 *
353 	 * Optional callback used by drm_irq_install() which is called after
354 	 * the interrupt handler is registered. This should be used to enable
355 	 * interrupt generation in the hardware.
356 	 */
357 	int (*irq_postinstall) (struct drm_device *dev);
358 
359 	/**
360 	 * @irq_uninstall:
361 	 *
362 	 * Optional callback used by drm_irq_uninstall() which is called before
363 	 * the interrupt handler is unregistered. This should be used to disable
364 	 * interrupt generation in the hardware.
365 	 */
366 	void (*irq_uninstall) (struct drm_device *dev);
367 
368 	/**
369 	 * @master_create:
370 	 *
371 	 * Called whenever a new master is created. Only used by vmwgfx.
372 	 */
373 	int (*master_create)(struct drm_device *dev, struct drm_master *master);
374 
375 	/**
376 	 * @master_destroy:
377 	 *
378 	 * Called whenever a master is destroyed. Only used by vmwgfx.
379 	 */
380 	void (*master_destroy)(struct drm_device *dev, struct drm_master *master);
381 
382 	/**
383 	 * @master_set:
384 	 *
385 	 * Called whenever the minor master is set. Only used by vmwgfx.
386 	 */
387 	int (*master_set)(struct drm_device *dev, struct drm_file *file_priv,
388 			  bool from_open);
389 	/**
390 	 * @master_drop:
391 	 *
392 	 * Called whenever the minor master is dropped. Only used by vmwgfx.
393 	 */
394 	void (*master_drop)(struct drm_device *dev, struct drm_file *file_priv);
395 
396 	/**
397 	 * @debugfs_init:
398 	 *
399 	 * Allows drivers to create driver-specific debugfs files.
400 	 */
401 	int (*debugfs_init)(struct drm_minor *minor);
402 
403 	/**
404 	 * @gem_free_object: deconstructor for drm_gem_objects
405 	 *
406 	 * This is deprecated and should not be used by new drivers. Use
407 	 * @gem_free_object_unlocked instead.
408 	 */
409 	void (*gem_free_object) (struct drm_gem_object *obj);
410 
411 	/**
412 	 * @gem_free_object_unlocked: deconstructor for drm_gem_objects
413 	 *
414 	 * This is for drivers which are not encumbered with &drm_device.struct_mutex
415 	 * legacy locking schemes. Use this hook instead of @gem_free_object.
416 	 */
417 	void (*gem_free_object_unlocked) (struct drm_gem_object *obj);
418 
419 	/**
420 	 * @gem_open_object:
421 	 *
422 	 * Driver hook called upon gem handle creation
423 	 */
424 	int (*gem_open_object) (struct drm_gem_object *, struct drm_file *);
425 
426 	/**
427 	 * @gem_close_object:
428 	 *
429 	 * Driver hook called upon gem handle release
430 	 */
431 	void (*gem_close_object) (struct drm_gem_object *, struct drm_file *);
432 
433 	/**
434 	 * @gem_print_info:
435 	 *
436 	 * If driver subclasses struct &drm_gem_object, it can implement this
437 	 * optional hook for printing additional driver specific info.
438 	 *
439 	 * drm_printf_indent() should be used in the callback passing it the
440 	 * indent argument.
441 	 *
442 	 * This callback is called from drm_gem_print_info().
443 	 */
444 	void (*gem_print_info)(struct drm_printer *p, unsigned int indent,
445 			       const struct drm_gem_object *obj);
446 
447 	/**
448 	 * @gem_create_object: constructor for gem objects
449 	 *
450 	 * Hook for allocating the GEM object struct, for use by core
451 	 * helpers.
452 	 */
453 	struct drm_gem_object *(*gem_create_object)(struct drm_device *dev,
454 						    size_t size);
455 
456 	/* prime: */
457 	/**
458 	 * @prime_handle_to_fd:
459 	 *
460 	 * export handle -> fd (see drm_gem_prime_handle_to_fd() helper)
461 	 */
462 	int (*prime_handle_to_fd)(struct drm_device *dev, struct drm_file *file_priv,
463 				uint32_t handle, uint32_t flags, int *prime_fd);
464 	/**
465 	 * @prime_fd_to_handle:
466 	 *
467 	 * import fd -> handle (see drm_gem_prime_fd_to_handle() helper)
468 	 */
469 	int (*prime_fd_to_handle)(struct drm_device *dev, struct drm_file *file_priv,
470 				int prime_fd, uint32_t *handle);
471 	/**
472 	 * @gem_prime_export:
473 	 *
474 	 * export GEM -> dmabuf
475 	 */
476 	struct dma_buf * (*gem_prime_export)(struct drm_device *dev,
477 				struct drm_gem_object *obj, int flags);
478 	/**
479 	 * @gem_prime_import:
480 	 *
481 	 * import dmabuf -> GEM
482 	 */
483 	struct drm_gem_object * (*gem_prime_import)(struct drm_device *dev,
484 				struct dma_buf *dma_buf);
485 	int (*gem_prime_pin)(struct drm_gem_object *obj);
486 	void (*gem_prime_unpin)(struct drm_gem_object *obj);
487 	struct reservation_object * (*gem_prime_res_obj)(
488 				struct drm_gem_object *obj);
489 	struct sg_table *(*gem_prime_get_sg_table)(struct drm_gem_object *obj);
490 	struct drm_gem_object *(*gem_prime_import_sg_table)(
491 				struct drm_device *dev,
492 				struct dma_buf_attachment *attach,
493 				struct sg_table *sgt);
494 	void *(*gem_prime_vmap)(struct drm_gem_object *obj);
495 	void (*gem_prime_vunmap)(struct drm_gem_object *obj, void *vaddr);
496 	int (*gem_prime_mmap)(struct drm_gem_object *obj,
497 				struct vm_area_struct *vma);
498 
499 	/**
500 	 * @dumb_create:
501 	 *
502 	 * This creates a new dumb buffer in the driver's backing storage manager (GEM,
503 	 * TTM or something else entirely) and returns the resulting buffer handle. This
504 	 * handle can then be wrapped up into a framebuffer modeset object.
505 	 *
506 	 * Note that userspace is not allowed to use such objects for render
507 	 * acceleration - drivers must create their own private ioctls for such a use
508 	 * case.
509 	 *
510 	 * Width, height and depth are specified in the &drm_mode_create_dumb
511 	 * argument. The callback needs to fill the handle, pitch and size for
512 	 * the created buffer.
513 	 *
514 	 * Called by the user via ioctl.
515 	 *
516 	 * Returns:
517 	 *
518 	 * Zero on success, negative errno on failure.
519 	 */
520 	int (*dumb_create)(struct drm_file *file_priv,
521 			   struct drm_device *dev,
522 			   struct drm_mode_create_dumb *args);
523 	/**
524 	 * @dumb_map_offset:
525 	 *
526 	 * Allocate an offset in the drm device node's address space to be able to
527 	 * memory map a dumb buffer. GEM-based drivers must use
528 	 * drm_gem_create_mmap_offset() to implement this.
529 	 *
530 	 * Called by the user via ioctl.
531 	 *
532 	 * Returns:
533 	 *
534 	 * Zero on success, negative errno on failure.
535 	 */
536 	int (*dumb_map_offset)(struct drm_file *file_priv,
537 			       struct drm_device *dev, uint32_t handle,
538 			       uint64_t *offset);
539 	/**
540 	 * @dumb_destroy:
541 	 *
542 	 * This destroys the userspace handle for the given dumb backing storage buffer.
543 	 * Since buffer objects must be reference counted in the kernel a buffer object
544 	 * won't be immediately freed if a framebuffer modeset object still uses it.
545 	 *
546 	 * Called by the user via ioctl.
547 	 *
548 	 * Returns:
549 	 *
550 	 * Zero on success, negative errno on failure.
551 	 */
552 	int (*dumb_destroy)(struct drm_file *file_priv,
553 			    struct drm_device *dev,
554 			    uint32_t handle);
555 
556 	/**
557 	 * @gem_vm_ops: Driver private ops for this object
558 	 */
559 	const struct vm_operations_struct *gem_vm_ops;
560 
561 	/** @major: driver major number */
562 	int major;
563 	/** @minor: driver minor number */
564 	int minor;
565 	/** @patchlevel: driver patch level */
566 	int patchlevel;
567 	/** @name: driver name */
568 	char *name;
569 	/** @desc: driver description */
570 	char *desc;
571 	/** @date: driver date */
572 	char *date;
573 
574 	/** @driver_features: driver features */
575 	u32 driver_features;
576 
577 	/**
578 	 * @ioctls:
579 	 *
580 	 * Array of driver-private IOCTL description entries. See the chapter on
581 	 * :ref:`IOCTL support in the userland interfaces
582 	 * chapter<drm_driver_ioctl>` for the full details.
583 	 */
584 
585 	const struct drm_ioctl_desc *ioctls;
586 	/** @num_ioctls: Number of entries in @ioctls. */
587 	int num_ioctls;
588 
589 	/**
590 	 * @fops:
591 	 *
592 	 * File operations for the DRM device node. See the discussion in
593 	 * :ref:`file operations<drm_driver_fops>` for in-depth coverage and
594 	 * some examples.
595 	 */
596 	const struct file_operations *fops;
597 
598 	/* Everything below here is for legacy driver, never use! */
599 	/* private: */
600 
601 	/* List of devices hanging off this driver with stealth attach. */
602 	struct list_head legacy_dev_list;
603 	int (*firstopen) (struct drm_device *);
604 	void (*preclose) (struct drm_device *, struct drm_file *file_priv);
605 	int (*dma_ioctl) (struct drm_device *dev, void *data, struct drm_file *file_priv);
606 	int (*dma_quiescent) (struct drm_device *);
607 	int (*context_dtor) (struct drm_device *dev, int context);
608 	int dev_priv_size;
609 };
610 
611 extern unsigned int drm_debug;
612 
613 int drm_dev_init(struct drm_device *dev,
614 		 struct drm_driver *driver,
615 		 struct device *parent);
616 void drm_dev_fini(struct drm_device *dev);
617 
618 struct drm_device *drm_dev_alloc(struct drm_driver *driver,
619 				 struct device *parent);
620 int drm_dev_register(struct drm_device *dev, unsigned long flags);
621 void drm_dev_unregister(struct drm_device *dev);
622 
623 void drm_dev_get(struct drm_device *dev);
624 void drm_dev_put(struct drm_device *dev);
625 void drm_dev_unref(struct drm_device *dev);
626 void drm_put_dev(struct drm_device *dev);
627 void drm_dev_unplug(struct drm_device *dev);
628 
629 /**
630  * drm_dev_is_unplugged - is a DRM device unplugged
631  * @dev: DRM device
632  *
633  * This function can be called to check whether a hotpluggable is unplugged.
634  * Unplugging itself is singalled through drm_dev_unplug(). If a device is
635  * unplugged, these two functions guarantee that any store before calling
636  * drm_dev_unplug() is visible to callers of this function after it completes
637  */
638 static inline int drm_dev_is_unplugged(struct drm_device *dev)
639 {
640 	int ret = atomic_read(&dev->unplugged);
641 	smp_rmb();
642 	return ret;
643 }
644 
645 
646 int drm_dev_set_unique(struct drm_device *dev, const char *name);
647 
648 
649 #endif
650