/*
* video-buf generic routine to get the next available buffer
*/
static inline void get_next_vbi_buf(struct cx231xx_dmaqueue *dma_q,
struct cx231xx_buffer **buf)
{
struct cx231xx_video_mode *vmode =
container_of(dma_q, struct cx231xx_video_mode, vidq);
struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
char *outp;
if (list_empty(&dma_q->active)) {
cx231xx_err(DRIVER_NAME ": No active queue to serve\n");
dev->vbi_mode.bulk_ctl.buf = NULL;
*buf = NULL;
return;
}
/* Get the next buffer */
*buf = list_entry(dma_q->active.next, struct cx231xx_buffer, vb.queue);
/* Cleans up buffer - Useful for testing for frame/URB loss */
outp = videobuf_to_vmalloc(&(*buf)->vb);
memset(outp, 0, (*buf)->vb.size);
dev->vbi_mode.bulk_ctl.buf = *buf;
return;
}
static void myvivi_timer_function(unsigned long data)
{
struct videobuf_vmalloc_memory *vbuf;
/*1,构造数据
数据放在哪里，从队列的头部把第一个buffer取出来将数据填充进去。然后将&buf->done中将进程唤醒。
*/
struct vb2_buffer *vb;
//从本地队列取出第一个buffer。
if (list_empty(&myvivi_vb_local_queue->active)) {//若链表是空的表明还没有APP关心这里的数据
goto out;
}
//若不是空的则从队列的头部取出第一个videobuf。
vb = list_entry(myvivi_vb_local_queue.next, struct vb2_buffer, queue);
if(!waitqueue_active(&vb->done_entry))
goto out;
//填充数据:
vbuf = videobuf_to_vmalloc(&vb);
memset(vbuf, 0, vb->vb2_queue.bufs);
/*2，唤醒进程:&buf->done中将进程唤醒。*/
wake_up(&vb->done_entry);
out:
/*3,修改timer的超时时间: 30fps--表示1秒内为30帧数据。
每30之1秒产生一帧数据。
*/
mod_timer(&myvivi_timer, jiffies + HZ/30);//每隔时间产生一幅数据。HZ是1秒钟。
}
int cx231xx_do_vbi_copy(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
u8 *p_buffer, u32 bytes_to_copy)
{
u8 *p_out_buffer = NULL;
u32 current_line_bytes_copied = 0;
struct cx231xx_buffer *buf;
u32 _line_size = dev->width << 1;
void *startwrite;
int offset, lencopy;
buf = dev->vbi_mode.isoc_ctl.buf;
if (buf == NULL)
return -EINVAL;
p_out_buffer = videobuf_to_vmalloc(&buf->vb);
if (dma_q->bytes_left_in_line != _line_size) {
current_line_bytes_copied =
_line_size - dma_q->bytes_left_in_line;
}
offset = (dma_q->lines_completed * _line_size) +
current_line_bytes_copied;
/* prepare destination address */
startwrite = p_out_buffer + offset;
lencopy = dma_q->bytes_left_in_line > bytes_to_copy ?
bytes_to_copy : dma_q->bytes_left_in_line;
memcpy(startwrite, p_buffer, lencopy);
return 0;
}
/*====================================================================*/
static void init_copy(struct video_data *video, bool index)
{
struct front_face *front = video->front;
video->field_count = index;
video->lines_copied = 0;
video->prev_left = 0 ;
video->dst = (char *)videobuf_to_vmalloc(front->curr_frame)
+ index * video->lines_size;
video->vbi->copied = 0; /* set it here */
}
static void myvivi_timer_function(unsigned long data)
{
struct videobuf_buffer *vb;
void *vbuf;
struct timeval ts;
/*1. 构造数据
* 从队列头部取出第一个video_buf,填充数据
*/
/*1.1 从本地队列取出第一个videobuf*/
if (list_empty(&myvivi_vb_local_queue)) {
goto out;
}
vb = list_entry(myvivi_vb_local_queue.next,
struct videobuf_buffer, queue);
/* Nobody is waiting on this buffer, return */
if (!waitqueue_active(&vb->done))
goto out;
/*1.2 填充数据*/
vbuf = videobuf_to_vmalloc(vb);
//memset(vbuf, 0xff, vb->size);
myvivi_fillbuff(vb);
vb->field_count++;
do_gettimeofday(&ts);
vb->ts = ts;
vb->state = VIDEOBUF_DONE;
/*1.3 把videobuf从本地队列中删除*/
list_del(&vb->queue);
/*2. 唤醒进程*/
wake_up(&vb->done);
out:
/*3. 修改超时时间 30fps
* 每 1/30 s ,产生一帧数据
*/
mod_timer(&myvivi_timer, jiffies + HZ/30);
}
