1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3     buffer queues.
4     Copyright (C) 2003-2004  Kevin Thayer <nufan_wfk at yahoo.com>
5     Copyright (C) 2004  Chris Kennedy <c@groovy.org>
6     Copyright (C) 2005-2007  Hans Verkuil <hverkuil@xs4all.nl>
7 
8  */
9 
10 #ifndef IVTV_QUEUE_H
11 #define IVTV_QUEUE_H
12 
13 #define IVTV_DMA_UNMAPPED	((u32) -1)
14 #define SLICED_VBI_PIO 0
15 
16 /* ivtv_buffer utility functions */
17 
18 static inline int ivtv_might_use_pio(struct ivtv_stream *s)
19 {
20 	return s->dma == DMA_NONE || (SLICED_VBI_PIO && s->type == IVTV_ENC_STREAM_TYPE_VBI);
21 }
22 
23 static inline int ivtv_use_pio(struct ivtv_stream *s)
24 {
25 	struct ivtv *itv = s->itv;
26 
27 	return s->dma == DMA_NONE ||
28 	    (SLICED_VBI_PIO && s->type == IVTV_ENC_STREAM_TYPE_VBI && itv->vbi.sliced_in->service_set);
29 }
30 
31 static inline int ivtv_might_use_dma(struct ivtv_stream *s)
32 {
33 	return s->dma != DMA_NONE;
34 }
35 
36 static inline int ivtv_use_dma(struct ivtv_stream *s)
37 {
38 	return !ivtv_use_pio(s);
39 }
40 
41 static inline void ivtv_buf_sync_for_cpu(struct ivtv_stream *s, struct ivtv_buffer *buf)
42 {
43 	if (ivtv_use_dma(s))
44 		dma_sync_single_for_cpu(&s->itv->pdev->dev, buf->dma_handle,
45 					s->buf_size + 256, s->dma);
46 }
47 
48 static inline void ivtv_buf_sync_for_device(struct ivtv_stream *s, struct ivtv_buffer *buf)
49 {
50 	if (ivtv_use_dma(s))
51 		dma_sync_single_for_device(&s->itv->pdev->dev,
52 					   buf->dma_handle, s->buf_size + 256,
53 					   s->dma);
54 }
55 
56 int ivtv_buf_copy_from_user(struct ivtv_stream *s, struct ivtv_buffer *buf, const char __user *src, int copybytes);
57 void ivtv_buf_swap(struct ivtv_buffer *buf);
58 
59 /* ivtv_queue utility functions */
60 void ivtv_queue_init(struct ivtv_queue *q);
61 void ivtv_enqueue(struct ivtv_stream *s, struct ivtv_buffer *buf, struct ivtv_queue *q);
62 struct ivtv_buffer *ivtv_dequeue(struct ivtv_stream *s, struct ivtv_queue *q);
63 int ivtv_queue_move(struct ivtv_stream *s, struct ivtv_queue *from, struct ivtv_queue *steal,
64 		    struct ivtv_queue *to, int needed_bytes);
65 void ivtv_flush_queues(struct ivtv_stream *s);
66 
67 /* ivtv_stream utility functions */
68 int ivtv_stream_alloc(struct ivtv_stream *s);
69 void ivtv_stream_free(struct ivtv_stream *s);
70 
71 static inline void ivtv_stream_sync_for_cpu(struct ivtv_stream *s)
72 {
73 	if (ivtv_use_dma(s))
74 		dma_sync_single_for_cpu(&s->itv->pdev->dev, s->sg_handle,
75 					sizeof(struct ivtv_sg_element),
76 					DMA_TO_DEVICE);
77 }
78 
79 static inline void ivtv_stream_sync_for_device(struct ivtv_stream *s)
80 {
81 	if (ivtv_use_dma(s))
82 		dma_sync_single_for_device(&s->itv->pdev->dev, s->sg_handle,
83 					   sizeof(struct ivtv_sg_element),
84 					   DMA_TO_DEVICE);
85 }
86 
87 #endif
88