include/drm/drm_flip_work.h

   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/workqueue.h>
  29
  30 /**
  31  * DOC: flip utils
  32  *
  33  * Util to queue up work to run from work-queue context after flip/vblank.
  34  * Typically this can be used to defer unref of framebuffer's, cursor
  35  * bo's, etc until after vblank.  The APIs are all safe (and lockless)
  36  * for up to one producer and once consumer at a time.  The single-consumer
  37  * aspect is ensured by committing the queued work to a single work-queue.
  38  */
  39
  40 struct drm_flip_work;
  41
  42 /*
  43  * drm_flip_func_t - callback function
  44  *
  45  * @work: the flip work
  46  * @val: value queued via drm_flip_work_queue()
  47  *
  48  * Callback function to be called for each of the  queue'd work items after
  49  * drm_flip_work_commit() is called.
  50  */
  51 typedef void (*drm_flip_func_t)(struct drm_flip_work *work, void *val);
  52
  53 /**
  54  * struct drm_flip_work - flip work queue
  55  * @name: debug name
  56  * @pending: number of queued but not committed items
  57  * @count: number of committed items
  58  * @func: callback fxn called for each committed item
  59  * @worker: worker which calls @func
  60  * @fifo: queue of committed items
  61  */
  62 struct drm_flip_work {
  63         const char *name;
  64         atomic_t pending, count;
  65         drm_flip_func_t func;
  66         struct work_struct worker;
  67         DECLARE_KFIFO_PTR(fifo, void *);
  68 };
  69
  70 void drm_flip_work_queue(struct drm_flip_work *work, void *val);
  71 void drm_flip_work_commit(struct drm_flip_work *work,
  72                 struct workqueue_struct *wq);
  73 int drm_flip_work_init(struct drm_flip_work *work, int size,
  74                 const char *name, drm_flip_func_t func);
  75 void drm_flip_work_cleanup(struct drm_flip_work *work);
  76
  77 #endif  /* DRM_FLIP_WORK_H */