xref: /openbmc/linux/include/drm/drm_flip_work.h (revision ee7da21a)
1 /*
2  * Copyright (C) 2013 Red Hat
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21  * SOFTWARE.
22  */
23 
24 #ifndef DRM_FLIP_WORK_H
25 #define DRM_FLIP_WORK_H
26 
27 #include <linux/kfifo.h>
28 #include <linux/spinlock.h>
29 #include <linux/workqueue.h>
30 
31 /**
32  * DOC: flip utils
33  *
34  * Util to queue up work to run from work-queue context after flip/vblank.
35  * Typically this can be used to defer unref of framebuffer's, cursor
36  * bo's, etc until after vblank.  The APIs are all thread-safe.
37  * Moreover, drm_flip_work_queue_task and drm_flip_work_queue can be called
38  * in atomic context.
39  */
40 
41 struct drm_flip_work;
42 
43 /*
44  * drm_flip_func_t - callback function
45  *
46  * @work: the flip work
47  * @val: value queued via drm_flip_work_queue()
48  *
49  * Callback function to be called for each of the  queue'd work items after
50  * drm_flip_work_commit() is called.
51  */
52 typedef void (*drm_flip_func_t)(struct drm_flip_work *work, void *val);
53 
54 /**
55  * struct drm_flip_task - flip work task
56  * @node: list entry element
57  * @data: data to pass to &drm_flip_work.func
58  */
59 struct drm_flip_task {
60 	struct list_head node;
61 	void *data;
62 };
63 
64 /**
65  * struct drm_flip_work - flip work queue
66  * @name: debug name
67  * @func: callback fxn called for each committed item
68  * @worker: worker which calls @func
69  * @queued: queued tasks
70  * @commited: commited tasks
71  * @lock: lock to access queued and commited lists
72  */
73 struct drm_flip_work {
74 	const char *name;
75 	drm_flip_func_t func;
76 	struct work_struct worker;
77 	struct list_head queued;
78 	struct list_head commited;
79 	spinlock_t lock;
80 };
81 
82 struct drm_flip_task *drm_flip_work_allocate_task(void *data, gfp_t flags);
83 void drm_flip_work_queue_task(struct drm_flip_work *work,
84 			      struct drm_flip_task *task);
85 void drm_flip_work_queue(struct drm_flip_work *work, void *val);
86 void drm_flip_work_commit(struct drm_flip_work *work,
87 		struct workqueue_struct *wq);
88 void drm_flip_work_init(struct drm_flip_work *work,
89 		const char *name, drm_flip_func_t func);
90 void drm_flip_work_cleanup(struct drm_flip_work *work);
91 
92 #endif  /* DRM_FLIP_WORK_H */
93