xref: /openbmc/linux/include/drm/drm_drv.h (revision ad0f449b)
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 /**
45  * enum drm_driver_feature - feature flags
46  *
47  * See &drm_driver.driver_features, drm_device.driver_features and
48  * drm_core_check_feature().
49  */
50 enum drm_driver_feature {
51 	/**
52 	 * @DRIVER_GEM:
53 	 *
54 	 * Driver use the GEM memory manager. This should be set for all modern
55 	 * drivers.
56 	 */
57 	DRIVER_GEM			= BIT(0),
58 	/**
59 	 * @DRIVER_MODESET:
60 	 *
61 	 * Driver supports mode setting interfaces (KMS).
62 	 */
63 	DRIVER_MODESET			= BIT(1),
64 	/**
65 	 * @DRIVER_RENDER:
66 	 *
67 	 * Driver supports dedicated render nodes. See also the :ref:`section on
68 	 * render nodes <drm_render_node>` for details.
69 	 */
70 	DRIVER_RENDER			= BIT(3),
71 	/**
72 	 * @DRIVER_ATOMIC:
73 	 *
74 	 * Driver supports the full atomic modesetting userspace API. Drivers
75 	 * which only use atomic internally, but do not the support the full
76 	 * userspace API (e.g. not all properties converted to atomic, or
77 	 * multi-plane updates are not guaranteed to be tear-free) should not
78 	 * set this flag.
79 	 */
80 	DRIVER_ATOMIC			= BIT(4),
81 	/**
82 	 * @DRIVER_SYNCOBJ:
83 	 *
84 	 * Driver supports &drm_syncobj for explicit synchronization of command
85 	 * submission.
86 	 */
87 	DRIVER_SYNCOBJ                  = BIT(5),
88 	/**
89 	 * @DRIVER_SYNCOBJ_TIMELINE:
90 	 *
91 	 * Driver supports the timeline flavor of &drm_syncobj for explicit
92 	 * synchronization of command submission.
93 	 */
94 	DRIVER_SYNCOBJ_TIMELINE         = BIT(6),
95 
96 	/* IMPORTANT: Below are all the legacy flags, add new ones above. */
97 
98 	/**
99 	 * @DRIVER_USE_AGP:
100 	 *
101 	 * Set up DRM AGP support, see drm_agp_init(), the DRM core will manage
102 	 * AGP resources. New drivers don't need this.
103 	 */
104 	DRIVER_USE_AGP			= BIT(25),
105 	/**
106 	 * @DRIVER_LEGACY:
107 	 *
108 	 * Denote a legacy driver using shadow attach. Do not use.
109 	 */
110 	DRIVER_LEGACY			= BIT(26),
111 	/**
112 	 * @DRIVER_PCI_DMA:
113 	 *
114 	 * Driver is capable of PCI DMA, mapping of PCI DMA buffers to userspace
115 	 * will be enabled. Only for legacy drivers. Do not use.
116 	 */
117 	DRIVER_PCI_DMA			= BIT(27),
118 	/**
119 	 * @DRIVER_SG:
120 	 *
121 	 * Driver can perform scatter/gather DMA, allocation and mapping of
122 	 * scatter/gather buffers will be enabled. Only for legacy drivers. Do
123 	 * not use.
124 	 */
125 	DRIVER_SG			= BIT(28),
126 
127 	/**
128 	 * @DRIVER_HAVE_DMA:
129 	 *
130 	 * Driver supports DMA, the userspace DMA API will be supported. Only
131 	 * for legacy drivers. Do not use.
132 	 */
133 	DRIVER_HAVE_DMA			= BIT(29),
134 	/**
135 	 * @DRIVER_HAVE_IRQ:
136 	 *
137 	 * Legacy irq support. Only for legacy drivers. Do not use.
138 	 *
139 	 * New drivers can either use the drm_irq_install() and
140 	 * drm_irq_uninstall() helper functions, or roll their own irq support
141 	 * code by calling request_irq() directly.
142 	 */
143 	DRIVER_HAVE_IRQ			= BIT(30),
144 	/**
145 	 * @DRIVER_KMS_LEGACY_CONTEXT:
146 	 *
147 	 * Used only by nouveau for backwards compatibility with existing
148 	 * userspace.  Do not use.
149 	 */
150 	DRIVER_KMS_LEGACY_CONTEXT	= BIT(31),
151 };
152 
153 /**
154  * struct drm_driver - DRM driver structure
155  *
156  * This structure represent the common code for a family of cards. There will be
157  * one &struct drm_device for each card present in this family. It contains lots
158  * of vfunc entries, and a pile of those probably should be moved to more
159  * appropriate places like &drm_mode_config_funcs or into a new operations
160  * structure for GEM drivers.
161  */
162 struct drm_driver {
163 	/**
164 	 * @load:
165 	 *
166 	 * Backward-compatible driver callback to complete
167 	 * initialization steps after the driver is registered.  For
168 	 * this reason, may suffer from race conditions and its use is
169 	 * deprecated for new drivers.  It is therefore only supported
170 	 * for existing drivers not yet converted to the new scheme.
171 	 * See drm_dev_init() and drm_dev_register() for proper and
172 	 * race-free way to set up a &struct drm_device.
173 	 *
174 	 * This is deprecated, do not use!
175 	 *
176 	 * Returns:
177 	 *
178 	 * Zero on success, non-zero value on failure.
179 	 */
180 	int (*load) (struct drm_device *, unsigned long flags);
181 
182 	/**
183 	 * @open:
184 	 *
185 	 * Driver callback when a new &struct drm_file is opened. Useful for
186 	 * setting up driver-private data structures like buffer allocators,
187 	 * execution contexts or similar things. Such driver-private resources
188 	 * must be released again in @postclose.
189 	 *
190 	 * Since the display/modeset side of DRM can only be owned by exactly
191 	 * one &struct drm_file (see &drm_file.is_master and &drm_device.master)
192 	 * there should never be a need to set up any modeset related resources
193 	 * in this callback. Doing so would be a driver design bug.
194 	 *
195 	 * Returns:
196 	 *
197 	 * 0 on success, a negative error code on failure, which will be
198 	 * promoted to userspace as the result of the open() system call.
199 	 */
200 	int (*open) (struct drm_device *, struct drm_file *);
201 
202 	/**
203 	 * @postclose:
204 	 *
205 	 * One of the driver callbacks when a new &struct drm_file is closed.
206 	 * Useful for tearing down driver-private data structures allocated in
207 	 * @open like buffer allocators, execution contexts or similar things.
208 	 *
209 	 * Since the display/modeset side of DRM can only be owned by exactly
210 	 * one &struct drm_file (see &drm_file.is_master and &drm_device.master)
211 	 * there should never be a need to tear down any modeset related
212 	 * resources in this callback. Doing so would be a driver design bug.
213 	 */
214 	void (*postclose) (struct drm_device *, struct drm_file *);
215 
216 	/**
217 	 * @lastclose:
218 	 *
219 	 * Called when the last &struct drm_file has been closed and there's
220 	 * currently no userspace client for the &struct drm_device.
221 	 *
222 	 * Modern drivers should only use this to force-restore the fbdev
223 	 * framebuffer using drm_fb_helper_restore_fbdev_mode_unlocked().
224 	 * Anything else would indicate there's something seriously wrong.
225 	 * Modern drivers can also use this to execute delayed power switching
226 	 * state changes, e.g. in conjunction with the :ref:`vga_switcheroo`
227 	 * infrastructure.
228 	 *
229 	 * This is called after @postclose hook has been called.
230 	 *
231 	 * NOTE:
232 	 *
233 	 * All legacy drivers use this callback to de-initialize the hardware.
234 	 * This is purely because of the shadow-attach model, where the DRM
235 	 * kernel driver does not really own the hardware. Instead ownershipe is
236 	 * handled with the help of userspace through an inheritedly racy dance
237 	 * to set/unset the VT into raw mode.
238 	 *
239 	 * Legacy drivers initialize the hardware in the @firstopen callback,
240 	 * which isn't even called for modern drivers.
241 	 */
242 	void (*lastclose) (struct drm_device *);
243 
244 	/**
245 	 * @unload:
246 	 *
247 	 * Reverse the effects of the driver load callback.  Ideally,
248 	 * the clean up performed by the driver should happen in the
249 	 * reverse order of the initialization.  Similarly to the load
250 	 * hook, this handler is deprecated and its usage should be
251 	 * dropped in favor of an open-coded teardown function at the
252 	 * driver layer.  See drm_dev_unregister() and drm_dev_put()
253 	 * for the proper way to remove a &struct drm_device.
254 	 *
255 	 * The unload() hook is called right after unregistering
256 	 * the device.
257 	 *
258 	 */
259 	void (*unload) (struct drm_device *);
260 
261 	/**
262 	 * @release:
263 	 *
264 	 * Optional callback for destroying device data after the final
265 	 * reference is released, i.e. the device is being destroyed.
266 	 *
267 	 * This is deprecated, clean up all memory allocations associated with a
268 	 * &drm_device using drmm_add_action(), drmm_kmalloc() and related
269 	 * managed resources functions.
270 	 */
271 	void (*release) (struct drm_device *);
272 
273 	/**
274 	 * @irq_handler:
275 	 *
276 	 * Interrupt handler called when using drm_irq_install(). Not used by
277 	 * drivers which implement their own interrupt handling.
278 	 */
279 	irqreturn_t(*irq_handler) (int irq, void *arg);
280 
281 	/**
282 	 * @irq_preinstall:
283 	 *
284 	 * Optional callback used by drm_irq_install() which is called before
285 	 * the interrupt handler is registered. This should be used to clear out
286 	 * any pending interrupts (from e.g. firmware based drives) and reset
287 	 * the interrupt handling registers.
288 	 */
289 	void (*irq_preinstall) (struct drm_device *dev);
290 
291 	/**
292 	 * @irq_postinstall:
293 	 *
294 	 * Optional callback used by drm_irq_install() which is called after
295 	 * the interrupt handler is registered. This should be used to enable
296 	 * interrupt generation in the hardware.
297 	 */
298 	int (*irq_postinstall) (struct drm_device *dev);
299 
300 	/**
301 	 * @irq_uninstall:
302 	 *
303 	 * Optional callback used by drm_irq_uninstall() which is called before
304 	 * the interrupt handler is unregistered. This should be used to disable
305 	 * interrupt generation in the hardware.
306 	 */
307 	void (*irq_uninstall) (struct drm_device *dev);
308 
309 	/**
310 	 * @master_set:
311 	 *
312 	 * Called whenever the minor master is set. Only used by vmwgfx.
313 	 */
314 	int (*master_set)(struct drm_device *dev, struct drm_file *file_priv,
315 			  bool from_open);
316 	/**
317 	 * @master_drop:
318 	 *
319 	 * Called whenever the minor master is dropped. Only used by vmwgfx.
320 	 */
321 	void (*master_drop)(struct drm_device *dev, struct drm_file *file_priv);
322 
323 	/**
324 	 * @debugfs_init:
325 	 *
326 	 * Allows drivers to create driver-specific debugfs files.
327 	 */
328 	void (*debugfs_init)(struct drm_minor *minor);
329 
330 	/**
331 	 * @gem_free_object_unlocked: deconstructor for drm_gem_objects
332 	 *
333 	 * This is deprecated and should not be used by new drivers. Use
334 	 * &drm_gem_object_funcs.free instead.
335 	 */
336 	void (*gem_free_object_unlocked) (struct drm_gem_object *obj);
337 
338 	/**
339 	 * @gem_open_object:
340 	 *
341 	 * This callback is deprecated in favour of &drm_gem_object_funcs.open.
342 	 *
343 	 * Driver hook called upon gem handle creation
344 	 */
345 	int (*gem_open_object) (struct drm_gem_object *, struct drm_file *);
346 
347 	/**
348 	 * @gem_close_object:
349 	 *
350 	 * This callback is deprecated in favour of &drm_gem_object_funcs.close.
351 	 *
352 	 * Driver hook called upon gem handle release
353 	 */
354 	void (*gem_close_object) (struct drm_gem_object *, struct drm_file *);
355 
356 	/**
357 	 * @gem_create_object: constructor for gem objects
358 	 *
359 	 * Hook for allocating the GEM object struct, for use by the CMA and
360 	 * SHMEM GEM helpers.
361 	 */
362 	struct drm_gem_object *(*gem_create_object)(struct drm_device *dev,
363 						    size_t size);
364 	/**
365 	 * @prime_handle_to_fd:
366 	 *
367 	 * Main PRIME export function. Should be implemented with
368 	 * drm_gem_prime_handle_to_fd() for GEM based drivers.
369 	 *
370 	 * For an in-depth discussion see :ref:`PRIME buffer sharing
371 	 * documentation <prime_buffer_sharing>`.
372 	 */
373 	int (*prime_handle_to_fd)(struct drm_device *dev, struct drm_file *file_priv,
374 				uint32_t handle, uint32_t flags, int *prime_fd);
375 	/**
376 	 * @prime_fd_to_handle:
377 	 *
378 	 * Main PRIME import function. Should be implemented with
379 	 * drm_gem_prime_fd_to_handle() for GEM based drivers.
380 	 *
381 	 * For an in-depth discussion see :ref:`PRIME buffer sharing
382 	 * documentation <prime_buffer_sharing>`.
383 	 */
384 	int (*prime_fd_to_handle)(struct drm_device *dev, struct drm_file *file_priv,
385 				int prime_fd, uint32_t *handle);
386 	/**
387 	 * @gem_prime_export:
388 	 *
389 	 * Export hook for GEM drivers. Deprecated in favour of
390 	 * &drm_gem_object_funcs.export.
391 	 */
392 	struct dma_buf * (*gem_prime_export)(struct drm_gem_object *obj,
393 					     int flags);
394 	/**
395 	 * @gem_prime_import:
396 	 *
397 	 * Import hook for GEM drivers.
398 	 *
399 	 * This defaults to drm_gem_prime_import() if not set.
400 	 */
401 	struct drm_gem_object * (*gem_prime_import)(struct drm_device *dev,
402 				struct dma_buf *dma_buf);
403 
404 	/**
405 	 * @gem_prime_pin:
406 	 *
407 	 * Deprecated hook in favour of &drm_gem_object_funcs.pin.
408 	 */
409 	int (*gem_prime_pin)(struct drm_gem_object *obj);
410 
411 	/**
412 	 * @gem_prime_unpin:
413 	 *
414 	 * Deprecated hook in favour of &drm_gem_object_funcs.unpin.
415 	 */
416 	void (*gem_prime_unpin)(struct drm_gem_object *obj);
417 
418 
419 	/**
420 	 * @gem_prime_get_sg_table:
421 	 *
422 	 * Deprecated hook in favour of &drm_gem_object_funcs.get_sg_table.
423 	 */
424 	struct sg_table *(*gem_prime_get_sg_table)(struct drm_gem_object *obj);
425 
426 	/**
427 	 * @gem_prime_import_sg_table:
428 	 *
429 	 * Optional hook used by the PRIME helper functions
430 	 * drm_gem_prime_import() respectively drm_gem_prime_import_dev().
431 	 */
432 	struct drm_gem_object *(*gem_prime_import_sg_table)(
433 				struct drm_device *dev,
434 				struct dma_buf_attachment *attach,
435 				struct sg_table *sgt);
436 	/**
437 	 * @gem_prime_vmap:
438 	 *
439 	 * Deprecated vmap hook for GEM drivers. Please use
440 	 * &drm_gem_object_funcs.vmap instead.
441 	 */
442 	void *(*gem_prime_vmap)(struct drm_gem_object *obj);
443 
444 	/**
445 	 * @gem_prime_vunmap:
446 	 *
447 	 * Deprecated vunmap hook for GEM drivers. Please use
448 	 * &drm_gem_object_funcs.vunmap instead.
449 	 */
450 	void (*gem_prime_vunmap)(struct drm_gem_object *obj, void *vaddr);
451 
452 	/**
453 	 * @gem_prime_mmap:
454 	 *
455 	 * mmap hook for GEM drivers, used to implement dma-buf mmap in the
456 	 * PRIME helpers.
457 	 *
458 	 * FIXME: There's way too much duplication going on here, and also moved
459 	 * to &drm_gem_object_funcs.
460 	 */
461 	int (*gem_prime_mmap)(struct drm_gem_object *obj,
462 				struct vm_area_struct *vma);
463 
464 	/**
465 	 * @dumb_create:
466 	 *
467 	 * This creates a new dumb buffer in the driver's backing storage manager (GEM,
468 	 * TTM or something else entirely) and returns the resulting buffer handle. This
469 	 * handle can then be wrapped up into a framebuffer modeset object.
470 	 *
471 	 * Note that userspace is not allowed to use such objects for render
472 	 * acceleration - drivers must create their own private ioctls for such a use
473 	 * case.
474 	 *
475 	 * Width, height and depth are specified in the &drm_mode_create_dumb
476 	 * argument. The callback needs to fill the handle, pitch and size for
477 	 * the created buffer.
478 	 *
479 	 * Called by the user via ioctl.
480 	 *
481 	 * Returns:
482 	 *
483 	 * Zero on success, negative errno on failure.
484 	 */
485 	int (*dumb_create)(struct drm_file *file_priv,
486 			   struct drm_device *dev,
487 			   struct drm_mode_create_dumb *args);
488 	/**
489 	 * @dumb_map_offset:
490 	 *
491 	 * Allocate an offset in the drm device node's address space to be able to
492 	 * memory map a dumb buffer.
493 	 *
494 	 * The default implementation is drm_gem_create_mmap_offset(). GEM based
495 	 * drivers must not overwrite this.
496 	 *
497 	 * Called by the user via ioctl.
498 	 *
499 	 * Returns:
500 	 *
501 	 * Zero on success, negative errno on failure.
502 	 */
503 	int (*dumb_map_offset)(struct drm_file *file_priv,
504 			       struct drm_device *dev, uint32_t handle,
505 			       uint64_t *offset);
506 	/**
507 	 * @dumb_destroy:
508 	 *
509 	 * This destroys the userspace handle for the given dumb backing storage buffer.
510 	 * Since buffer objects must be reference counted in the kernel a buffer object
511 	 * won't be immediately freed if a framebuffer modeset object still uses it.
512 	 *
513 	 * Called by the user via ioctl.
514 	 *
515 	 * The default implementation is drm_gem_dumb_destroy(). GEM based drivers
516 	 * must not overwrite this.
517 	 *
518 	 * Returns:
519 	 *
520 	 * Zero on success, negative errno on failure.
521 	 */
522 	int (*dumb_destroy)(struct drm_file *file_priv,
523 			    struct drm_device *dev,
524 			    uint32_t handle);
525 
526 	/**
527 	 * @gem_vm_ops: Driver private ops for this object
528 	 *
529 	 * For GEM drivers this is deprecated in favour of
530 	 * &drm_gem_object_funcs.vm_ops.
531 	 */
532 	const struct vm_operations_struct *gem_vm_ops;
533 
534 	/** @major: driver major number */
535 	int major;
536 	/** @minor: driver minor number */
537 	int minor;
538 	/** @patchlevel: driver patch level */
539 	int patchlevel;
540 	/** @name: driver name */
541 	char *name;
542 	/** @desc: driver description */
543 	char *desc;
544 	/** @date: driver date */
545 	char *date;
546 
547 	/**
548 	 * @driver_features:
549 	 * Driver features, see &enum drm_driver_feature. Drivers can disable
550 	 * some features on a per-instance basis using
551 	 * &drm_device.driver_features.
552 	 */
553 	u32 driver_features;
554 
555 	/**
556 	 * @ioctls:
557 	 *
558 	 * Array of driver-private IOCTL description entries. See the chapter on
559 	 * :ref:`IOCTL support in the userland interfaces
560 	 * chapter<drm_driver_ioctl>` for the full details.
561 	 */
562 
563 	const struct drm_ioctl_desc *ioctls;
564 	/** @num_ioctls: Number of entries in @ioctls. */
565 	int num_ioctls;
566 
567 	/**
568 	 * @fops:
569 	 *
570 	 * File operations for the DRM device node. See the discussion in
571 	 * :ref:`file operations<drm_driver_fops>` for in-depth coverage and
572 	 * some examples.
573 	 */
574 	const struct file_operations *fops;
575 
576 	/* Everything below here is for legacy driver, never use! */
577 	/* private: */
578 
579 	/* List of devices hanging off this driver with stealth attach. */
580 	struct list_head legacy_dev_list;
581 	int (*firstopen) (struct drm_device *);
582 	void (*preclose) (struct drm_device *, struct drm_file *file_priv);
583 	int (*dma_ioctl) (struct drm_device *dev, void *data, struct drm_file *file_priv);
584 	int (*dma_quiescent) (struct drm_device *);
585 	int (*context_dtor) (struct drm_device *dev, int context);
586 	u32 (*get_vblank_counter)(struct drm_device *dev, unsigned int pipe);
587 	int (*enable_vblank)(struct drm_device *dev, unsigned int pipe);
588 	void (*disable_vblank)(struct drm_device *dev, unsigned int pipe);
589 	int dev_priv_size;
590 };
591 
592 int drm_dev_init(struct drm_device *dev,
593 		 struct drm_driver *driver,
594 		 struct device *parent);
595 int devm_drm_dev_init(struct device *parent,
596 		      struct drm_device *dev,
597 		      struct drm_driver *driver);
598 
599 void *__devm_drm_dev_alloc(struct device *parent, struct drm_driver *driver,
600 			   size_t size, size_t offset);
601 
602 /**
603  * devm_drm_dev_alloc - Resource managed allocation of a &drm_device instance
604  * @parent: Parent device object
605  * @driver: DRM driver
606  * @type: the type of the struct which contains struct &drm_device
607  * @member: the name of the &drm_device within @type.
608  *
609  * This allocates and initialize a new DRM device. No device registration is done.
610  * Call drm_dev_register() to advertice the device to user space and register it
611  * with other core subsystems. This should be done last in the device
612  * initialization sequence to make sure userspace can't access an inconsistent
613  * state.
614  *
615  * The initial ref-count of the object is 1. Use drm_dev_get() and
616  * drm_dev_put() to take and drop further ref-counts.
617  *
618  * It is recommended that drivers embed &struct drm_device into their own device
619  * structure.
620  *
621  * Note that this manages the lifetime of the resulting &drm_device
622  * automatically using devres. The DRM device initialized with this function is
623  * automatically put on driver detach using drm_dev_put().
624  *
625  * RETURNS:
626  * Pointer to new DRM device, or ERR_PTR on failure.
627  */
628 #define devm_drm_dev_alloc(parent, driver, type, member) \
629 	((type *) __devm_drm_dev_alloc(parent, driver, sizeof(type), \
630 				       offsetof(type, member)))
631 
632 struct drm_device *drm_dev_alloc(struct drm_driver *driver,
633 				 struct device *parent);
634 int drm_dev_register(struct drm_device *dev, unsigned long flags);
635 void drm_dev_unregister(struct drm_device *dev);
636 
637 void drm_dev_get(struct drm_device *dev);
638 void drm_dev_put(struct drm_device *dev);
639 void drm_put_dev(struct drm_device *dev);
640 bool drm_dev_enter(struct drm_device *dev, int *idx);
641 void drm_dev_exit(int idx);
642 void drm_dev_unplug(struct drm_device *dev);
643 
644 /**
645  * drm_dev_is_unplugged - is a DRM device unplugged
646  * @dev: DRM device
647  *
648  * This function can be called to check whether a hotpluggable is unplugged.
649  * Unplugging itself is singalled through drm_dev_unplug(). If a device is
650  * unplugged, these two functions guarantee that any store before calling
651  * drm_dev_unplug() is visible to callers of this function after it completes
652  *
653  * WARNING: This function fundamentally races against drm_dev_unplug(). It is
654  * recommended that drivers instead use the underlying drm_dev_enter() and
655  * drm_dev_exit() function pairs.
656  */
657 static inline bool drm_dev_is_unplugged(struct drm_device *dev)
658 {
659 	int idx;
660 
661 	if (drm_dev_enter(dev, &idx)) {
662 		drm_dev_exit(idx);
663 		return false;
664 	}
665 
666 	return true;
667 }
668 
669 /**
670  * drm_core_check_all_features - check driver feature flags mask
671  * @dev: DRM device to check
672  * @features: feature flag(s) mask
673  *
674  * This checks @dev for driver features, see &drm_driver.driver_features,
675  * &drm_device.driver_features, and the various &enum drm_driver_feature flags.
676  *
677  * Returns true if all features in the @features mask are supported, false
678  * otherwise.
679  */
680 static inline bool drm_core_check_all_features(const struct drm_device *dev,
681 					       u32 features)
682 {
683 	u32 supported = dev->driver->driver_features & dev->driver_features;
684 
685 	return features && (supported & features) == features;
686 }
687 
688 /**
689  * drm_core_check_feature - check driver feature flags
690  * @dev: DRM device to check
691  * @feature: feature flag
692  *
693  * This checks @dev for driver features, see &drm_driver.driver_features,
694  * &drm_device.driver_features, and the various &enum drm_driver_feature flags.
695  *
696  * Returns true if the @feature is supported, false otherwise.
697  */
698 static inline bool drm_core_check_feature(const struct drm_device *dev,
699 					  enum drm_driver_feature feature)
700 {
701 	return drm_core_check_all_features(dev, feature);
702 }
703 
704 /**
705  * drm_drv_uses_atomic_modeset - check if the driver implements
706  * atomic_commit()
707  * @dev: DRM device
708  *
709  * This check is useful if drivers do not have DRIVER_ATOMIC set but
710  * have atomic modesetting internally implemented.
711  */
712 static inline bool drm_drv_uses_atomic_modeset(struct drm_device *dev)
713 {
714 	return drm_core_check_feature(dev, DRIVER_ATOMIC) ||
715 		(dev->mode_config.funcs && dev->mode_config.funcs->atomic_commit != NULL);
716 }
717 
718 
719 int drm_dev_set_unique(struct drm_device *dev, const char *name);
720 
721 
722 #endif
723