/*
* Copyright (C) 2013 Red Hat
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include "drmP.h"
#include "drm_flip_work.h"
/**
* drm_flip_work_queue - queue work
* @work: the flip-work
* @val: the value to queue
*
* Queues work, that will later be run (passed back to drm_flip_func_t
* func) on a work queue after drm_flip_work_commit() is called.
*/
void drm_flip_work_queue(struct drm_flip_work *work, void *val)
{
if (kfifo_put(&work->fifo, val)) {
atomic_inc(&work->pending);
} else {
DRM_ERROR("%s fifo full!\n", work->name);
work->func(work, val);
}
}
EXPORT_SYMBOL(drm_flip_work_queue);
/**
* drm_flip_work_commit - commit queued work
* @work: the flip-work
* @wq: the work-queue to run the queued work on
*
* Trigger work previously queued by drm_flip_work_queue() to run
* on a workqueue. The typical usage would be to queue work (via
* drm_flip_work_queue()) at any point (from vblank irq and/or
* prior), and then from vblank irq commit the queued work.
*/
void drm_flip_work_commit(struct drm_flip_work *work,
struct workqueue_struct *wq)
{
uint32_t pending = atomic_read(&work->pending);
atomic_add(pending, &work->count);
atomic_sub(pending, &work->pending);
queue_work(wq, &work->worker);
}
EXPORT_SYMBOL(drm_flip_work_commit);
static void flip_worker(struct work_struct *w)
{
struct drm_flip_work *work = container_of(w, struct drm_flip_work, worker);
uint32_t count = atomic_read(&work->count);
void *val = NULL;
atomic_sub(count, &work->count);
while(count--)
if (!WARN_ON(!kfifo_get(&work->fifo, &val)))
work->func(work, val);
}
/**
* drm_flip_work_init - initialize flip-work
* @work: the flip-work to initialize
* @size: the max queue depth
* @name: debug name
* @func: the callback work function
*
* Initializes/allocates resources for the flip-work
*
* RETURNS:
* Zero on success, error code on failure.
*/
int drm_flip_work_init(struct drm_flip_work *work, int size,
const char *name, drm_flip_func_t func)
{
int ret;
work->name = name;
atomic_set(&work->count, 0);
atomic_set(&work->pending, 0);
work->func = func;
ret = kfifo_alloc(&work->fifo, size, GFP_KERNEL);
if (ret) {
DRM_ERROR("could not allocate %s fifo\n", name);
return ret;
}
INIT_WORK(&work->worker, flip_worker);
return 0;
}
EXPORT_SYMBOL(drm_flip_work_init);
/**
* drm_flip_work_cleanup - cleans up flip-work
* @work: the flip-work to cleanup
*
* Destroy resources allocated for the flip-work
*/
void drm_flip_work_cleanup(struct drm_flip_work *work)
{
WARN_ON(!kfifo_is_empty(&work->fifo));
kfifo_free(&work->fifo);
}
EXPORT_SYMBOL(drm_flip_work_cleanup);
