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 == PCI_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 == PCI_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 != PCI_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 		pci_dma_sync_single_for_cpu(s->itv->pdev, 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 		pci_dma_sync_single_for_device(s->itv->pdev, buf->dma_handle,
52 				s->buf_size + 256, s->dma);
53 }
54 
55 int ivtv_buf_copy_from_user(struct ivtv_stream *s, struct ivtv_buffer *buf, const char __user *src, int copybytes);
56 void ivtv_buf_swap(struct ivtv_buffer *buf);
57 
58 /* ivtv_queue utility functions */
59 void ivtv_queue_init(struct ivtv_queue *q);
60 void ivtv_enqueue(struct ivtv_stream *s, struct ivtv_buffer *buf, struct ivtv_queue *q);
61 struct ivtv_buffer *ivtv_dequeue(struct ivtv_stream *s, struct ivtv_queue *q);
62 int ivtv_queue_move(struct ivtv_stream *s, struct ivtv_queue *from, struct ivtv_queue *steal,
63 		    struct ivtv_queue *to, int needed_bytes);
64 void ivtv_flush_queues(struct ivtv_stream *s);
65 
66 /* ivtv_stream utility functions */
67 int ivtv_stream_alloc(struct ivtv_stream *s);
68 void ivtv_stream_free(struct ivtv_stream *s);
69 
70 static inline void ivtv_stream_sync_for_cpu(struct ivtv_stream *s)
71 {
72 	if (ivtv_use_dma(s))
73 		pci_dma_sync_single_for_cpu(s->itv->pdev, s->sg_handle,
74 			sizeof(struct ivtv_sg_element), PCI_DMA_TODEVICE);
75 }
76 
77 static inline void ivtv_stream_sync_for_device(struct ivtv_stream *s)
78 {
79 	if (ivtv_use_dma(s))
80 		pci_dma_sync_single_for_device(s->itv->pdev, s->sg_handle,
81 			sizeof(struct ivtv_sg_element), PCI_DMA_TODEVICE);
82 }
83 
84 #endif
85