xref: /linux/include/drm/drm_drv.h (revision 312b62b6610cabea4cb535fd4889c41e9a84afca)
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: 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) (struct drm_gem_object *obj);
337 
338 	/**
339 	 * @gem_free_object_unlocked: deconstructor for drm_gem_objects
340 	 *
341 	 * This is deprecated and should not be used by new drivers. Use
342 	 * &drm_gem_object_funcs.free instead.
343 	 * Compared to @gem_free_object this is not encumbered with
344 	 * &drm_device.struct_mutex legacy locking schemes.
345 	 */
346 	void (*gem_free_object_unlocked) (struct drm_gem_object *obj);
347 
348 	/**
349 	 * @gem_open_object:
350 	 *
351 	 * This callback is deprecated in favour of &drm_gem_object_funcs.open.
352 	 *
353 	 * Driver hook called upon gem handle creation
354 	 */
355 	int (*gem_open_object) (struct drm_gem_object *, struct drm_file *);
356 
357 	/**
358 	 * @gem_close_object:
359 	 *
360 	 * This callback is deprecated in favour of &drm_gem_object_funcs.close.
361 	 *
362 	 * Driver hook called upon gem handle release
363 	 */
364 	void (*gem_close_object) (struct drm_gem_object *, struct drm_file *);
365 
366 	/**
367 	 * @gem_print_info:
368 	 *
369 	 * This callback is deprecated in favour of
370 	 * &drm_gem_object_funcs.print_info.
371 	 *
372 	 * If driver subclasses struct &drm_gem_object, it can implement this
373 	 * optional hook for printing additional driver specific info.
374 	 *
375 	 * drm_printf_indent() should be used in the callback passing it the
376 	 * indent argument.
377 	 *
378 	 * This callback is called from drm_gem_print_info().
379 	 */
380 	void (*gem_print_info)(struct drm_printer *p, unsigned int indent,
381 			       const struct drm_gem_object *obj);
382 
383 	/**
384 	 * @gem_create_object: constructor for gem objects
385 	 *
386 	 * Hook for allocating the GEM object struct, for use by the CMA and
387 	 * SHMEM GEM helpers.
388 	 */
389 	struct drm_gem_object *(*gem_create_object)(struct drm_device *dev,
390 						    size_t size);
391 	/**
392 	 * @prime_handle_to_fd:
393 	 *
394 	 * Main PRIME export function. Should be implemented with
395 	 * drm_gem_prime_handle_to_fd() for GEM based drivers.
396 	 *
397 	 * For an in-depth discussion see :ref:`PRIME buffer sharing
398 	 * documentation <prime_buffer_sharing>`.
399 	 */
400 	int (*prime_handle_to_fd)(struct drm_device *dev, struct drm_file *file_priv,
401 				uint32_t handle, uint32_t flags, int *prime_fd);
402 	/**
403 	 * @prime_fd_to_handle:
404 	 *
405 	 * Main PRIME import function. Should be implemented with
406 	 * drm_gem_prime_fd_to_handle() for GEM based drivers.
407 	 *
408 	 * For an in-depth discussion see :ref:`PRIME buffer sharing
409 	 * documentation <prime_buffer_sharing>`.
410 	 */
411 	int (*prime_fd_to_handle)(struct drm_device *dev, struct drm_file *file_priv,
412 				int prime_fd, uint32_t *handle);
413 	/**
414 	 * @gem_prime_export:
415 	 *
416 	 * Export hook for GEM drivers. Deprecated in favour of
417 	 * &drm_gem_object_funcs.export.
418 	 */
419 	struct dma_buf * (*gem_prime_export)(struct drm_gem_object *obj,
420 					     int flags);
421 	/**
422 	 * @gem_prime_import:
423 	 *
424 	 * Import hook for GEM drivers.
425 	 *
426 	 * This defaults to drm_gem_prime_import() if not set.
427 	 */
428 	struct drm_gem_object * (*gem_prime_import)(struct drm_device *dev,
429 				struct dma_buf *dma_buf);
430 
431 	/**
432 	 * @gem_prime_pin:
433 	 *
434 	 * Deprecated hook in favour of &drm_gem_object_funcs.pin.
435 	 */
436 	int (*gem_prime_pin)(struct drm_gem_object *obj);
437 
438 	/**
439 	 * @gem_prime_unpin:
440 	 *
441 	 * Deprecated hook in favour of &drm_gem_object_funcs.unpin.
442 	 */
443 	void (*gem_prime_unpin)(struct drm_gem_object *obj);
444 
445 
446 	/**
447 	 * @gem_prime_get_sg_table:
448 	 *
449 	 * Deprecated hook in favour of &drm_gem_object_funcs.get_sg_table.
450 	 */
451 	struct sg_table *(*gem_prime_get_sg_table)(struct drm_gem_object *obj);
452 
453 	/**
454 	 * @gem_prime_import_sg_table:
455 	 *
456 	 * Optional hook used by the PRIME helper functions
457 	 * drm_gem_prime_import() respectively drm_gem_prime_import_dev().
458 	 */
459 	struct drm_gem_object *(*gem_prime_import_sg_table)(
460 				struct drm_device *dev,
461 				struct dma_buf_attachment *attach,
462 				struct sg_table *sgt);
463 	/**
464 	 * @gem_prime_vmap:
465 	 *
466 	 * Deprecated vmap hook for GEM drivers. Please use
467 	 * &drm_gem_object_funcs.vmap instead.
468 	 */
469 	void *(*gem_prime_vmap)(struct drm_gem_object *obj);
470 
471 	/**
472 	 * @gem_prime_vunmap:
473 	 *
474 	 * Deprecated vunmap hook for GEM drivers. Please use
475 	 * &drm_gem_object_funcs.vunmap instead.
476 	 */
477 	void (*gem_prime_vunmap)(struct drm_gem_object *obj, void *vaddr);
478 
479 	/**
480 	 * @gem_prime_mmap:
481 	 *
482 	 * mmap hook for GEM drivers, used to implement dma-buf mmap in the
483 	 * PRIME helpers.
484 	 *
485 	 * FIXME: There's way too much duplication going on here, and also moved
486 	 * to &drm_gem_object_funcs.
487 	 */
488 	int (*gem_prime_mmap)(struct drm_gem_object *obj,
489 				struct vm_area_struct *vma);
490 
491 	/**
492 	 * @dumb_create:
493 	 *
494 	 * This creates a new dumb buffer in the driver's backing storage manager (GEM,
495 	 * TTM or something else entirely) and returns the resulting buffer handle. This
496 	 * handle can then be wrapped up into a framebuffer modeset object.
497 	 *
498 	 * Note that userspace is not allowed to use such objects for render
499 	 * acceleration - drivers must create their own private ioctls for such a use
500 	 * case.
501 	 *
502 	 * Width, height and depth are specified in the &drm_mode_create_dumb
503 	 * argument. The callback needs to fill the handle, pitch and size for
504 	 * the created buffer.
505 	 *
506 	 * Called by the user via ioctl.
507 	 *
508 	 * Returns:
509 	 *
510 	 * Zero on success, negative errno on failure.
511 	 */
512 	int (*dumb_create)(struct drm_file *file_priv,
513 			   struct drm_device *dev,
514 			   struct drm_mode_create_dumb *args);
515 	/**
516 	 * @dumb_map_offset:
517 	 *
518 	 * Allocate an offset in the drm device node's address space to be able to
519 	 * memory map a dumb buffer.
520 	 *
521 	 * The default implementation is drm_gem_create_mmap_offset(). GEM based
522 	 * drivers must not overwrite this.
523 	 *
524 	 * Called by the user via ioctl.
525 	 *
526 	 * Returns:
527 	 *
528 	 * Zero on success, negative errno on failure.
529 	 */
530 	int (*dumb_map_offset)(struct drm_file *file_priv,
531 			       struct drm_device *dev, uint32_t handle,
532 			       uint64_t *offset);
533 	/**
534 	 * @dumb_destroy:
535 	 *
536 	 * This destroys the userspace handle for the given dumb backing storage buffer.
537 	 * Since buffer objects must be reference counted in the kernel a buffer object
538 	 * won't be immediately freed if a framebuffer modeset object still uses it.
539 	 *
540 	 * Called by the user via ioctl.
541 	 *
542 	 * The default implementation is drm_gem_dumb_destroy(). GEM based drivers
543 	 * must not overwrite this.
544 	 *
545 	 * Returns:
546 	 *
547 	 * Zero on success, negative errno on failure.
548 	 */
549 	int (*dumb_destroy)(struct drm_file *file_priv,
550 			    struct drm_device *dev,
551 			    uint32_t handle);
552 
553 	/**
554 	 * @gem_vm_ops: Driver private ops for this object
555 	 *
556 	 * For GEM drivers this is deprecated in favour of
557 	 * &drm_gem_object_funcs.vm_ops.
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 	/**
575 	 * @driver_features:
576 	 * Driver features, see &enum drm_driver_feature. Drivers can disable
577 	 * some features on a per-instance basis using
578 	 * &drm_device.driver_features.
579 	 */
580 	u32 driver_features;
581 
582 	/**
583 	 * @ioctls:
584 	 *
585 	 * Array of driver-private IOCTL description entries. See the chapter on
586 	 * :ref:`IOCTL support in the userland interfaces
587 	 * chapter<drm_driver_ioctl>` for the full details.
588 	 */
589 
590 	const struct drm_ioctl_desc *ioctls;
591 	/** @num_ioctls: Number of entries in @ioctls. */
592 	int num_ioctls;
593 
594 	/**
595 	 * @fops:
596 	 *
597 	 * File operations for the DRM device node. See the discussion in
598 	 * :ref:`file operations<drm_driver_fops>` for in-depth coverage and
599 	 * some examples.
600 	 */
601 	const struct file_operations *fops;
602 
603 	/* Everything below here is for legacy driver, never use! */
604 	/* private: */
605 
606 	/* List of devices hanging off this driver with stealth attach. */
607 	struct list_head legacy_dev_list;
608 	int (*firstopen) (struct drm_device *);
609 	void (*preclose) (struct drm_device *, struct drm_file *file_priv);
610 	int (*dma_ioctl) (struct drm_device *dev, void *data, struct drm_file *file_priv);
611 	int (*dma_quiescent) (struct drm_device *);
612 	int (*context_dtor) (struct drm_device *dev, int context);
613 	u32 (*get_vblank_counter)(struct drm_device *dev, unsigned int pipe);
614 	int (*enable_vblank)(struct drm_device *dev, unsigned int pipe);
615 	void (*disable_vblank)(struct drm_device *dev, unsigned int pipe);
616 	int dev_priv_size;
617 };
618 
619 int drm_dev_init(struct drm_device *dev,
620 		 struct drm_driver *driver,
621 		 struct device *parent);
622 int devm_drm_dev_init(struct device *parent,
623 		      struct drm_device *dev,
624 		      struct drm_driver *driver);
625 
626 void *__devm_drm_dev_alloc(struct device *parent, struct drm_driver *driver,
627 			   size_t size, size_t offset);
628 
629 /**
630  * devm_drm_dev_alloc - Resource managed allocation of a &drm_device instance
631  * @parent: Parent device object
632  * @driver: DRM driver
633  * @type: the type of the struct which contains struct &drm_device
634  * @member: the name of the &drm_device within @type.
635  *
636  * This allocates and initialize a new DRM device. No device registration is done.
637  * Call drm_dev_register() to advertice the device to user space and register it
638  * with other core subsystems. This should be done last in the device
639  * initialization sequence to make sure userspace can't access an inconsistent
640  * state.
641  *
642  * The initial ref-count of the object is 1. Use drm_dev_get() and
643  * drm_dev_put() to take and drop further ref-counts.
644  *
645  * It is recommended that drivers embed &struct drm_device into their own device
646  * structure.
647  *
648  * Note that this manages the lifetime of the resulting &drm_device
649  * automatically using devres. The DRM device initialized with this function is
650  * automatically put on driver detach using drm_dev_put().
651  *
652  * RETURNS:
653  * Pointer to new DRM device, or ERR_PTR on failure.
654  */
655 #define devm_drm_dev_alloc(parent, driver, type, member) \
656 	((type *) __devm_drm_dev_alloc(parent, driver, sizeof(type), \
657 				       offsetof(type, member)))
658 
659 struct drm_device *drm_dev_alloc(struct drm_driver *driver,
660 				 struct device *parent);
661 int drm_dev_register(struct drm_device *dev, unsigned long flags);
662 void drm_dev_unregister(struct drm_device *dev);
663 
664 void drm_dev_get(struct drm_device *dev);
665 void drm_dev_put(struct drm_device *dev);
666 void drm_put_dev(struct drm_device *dev);
667 bool drm_dev_enter(struct drm_device *dev, int *idx);
668 void drm_dev_exit(int idx);
669 void drm_dev_unplug(struct drm_device *dev);
670 
671 /**
672  * drm_dev_is_unplugged - is a DRM device unplugged
673  * @dev: DRM device
674  *
675  * This function can be called to check whether a hotpluggable is unplugged.
676  * Unplugging itself is singalled through drm_dev_unplug(). If a device is
677  * unplugged, these two functions guarantee that any store before calling
678  * drm_dev_unplug() is visible to callers of this function after it completes
679  *
680  * WARNING: This function fundamentally races against drm_dev_unplug(). It is
681  * recommended that drivers instead use the underlying drm_dev_enter() and
682  * drm_dev_exit() function pairs.
683  */
684 static inline bool drm_dev_is_unplugged(struct drm_device *dev)
685 {
686 	int idx;
687 
688 	if (drm_dev_enter(dev, &idx)) {
689 		drm_dev_exit(idx);
690 		return false;
691 	}
692 
693 	return true;
694 }
695 
696 /**
697  * drm_core_check_all_features - check driver feature flags mask
698  * @dev: DRM device to check
699  * @features: feature flag(s) mask
700  *
701  * This checks @dev for driver features, see &drm_driver.driver_features,
702  * &drm_device.driver_features, and the various &enum drm_driver_feature flags.
703  *
704  * Returns true if all features in the @features mask are supported, false
705  * otherwise.
706  */
707 static inline bool drm_core_check_all_features(const struct drm_device *dev,
708 					       u32 features)
709 {
710 	u32 supported = dev->driver->driver_features & dev->driver_features;
711 
712 	return features && (supported & features) == features;
713 }
714 
715 /**
716  * drm_core_check_feature - check driver feature flags
717  * @dev: DRM device to check
718  * @feature: feature flag
719  *
720  * This checks @dev for driver features, see &drm_driver.driver_features,
721  * &drm_device.driver_features, and the various &enum drm_driver_feature flags.
722  *
723  * Returns true if the @feature is supported, false otherwise.
724  */
725 static inline bool drm_core_check_feature(const struct drm_device *dev,
726 					  enum drm_driver_feature feature)
727 {
728 	return drm_core_check_all_features(dev, feature);
729 }
730 
731 /**
732  * drm_drv_uses_atomic_modeset - check if the driver implements
733  * atomic_commit()
734  * @dev: DRM device
735  *
736  * This check is useful if drivers do not have DRIVER_ATOMIC set but
737  * have atomic modesetting internally implemented.
738  */
739 static inline bool drm_drv_uses_atomic_modeset(struct drm_device *dev)
740 {
741 	return drm_core_check_feature(dev, DRIVER_ATOMIC) ||
742 		(dev->mode_config.funcs && dev->mode_config.funcs->atomic_commit != NULL);
743 }
744 
745 
746 int drm_dev_set_unique(struct drm_device *dev, const char *name);
747 
748 
749 #endif
750