aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/media/video/cx18/cx18-queue.c
blob: dbe792ac30015d68c760a1d42b2731f7a043042e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
/*
 *  cx18 buffer queues
 *
 *  Derived from ivtv-queue.c
 *
 *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
 *  02111-1307  USA
 */

#include "cx18-driver.h"
#include "cx18-streams.h"
#include "cx18-queue.h"
#include "cx18-scb.h"

void cx18_buf_swap(struct cx18_buffer *buf)
{
	int i;

	for (i = 0; i < buf->bytesused; i += 4)
		swab32s((u32 *)(buf->buf + i));
}

void cx18_queue_init(struct cx18_queue *q)
{
	INIT_LIST_HEAD(&q->list);
	q->buffers = 0;
	q->length = 0;
	q->bytesused = 0;
}

void cx18_enqueue(struct cx18_stream *s, struct cx18_buffer *buf,
		struct cx18_queue *q)
{
	unsigned long flags = 0;

	/* clear the buffer if it is going to be enqueued to the free queue */
	if (q == &s->q_free) {
		buf->bytesused = 0;
		buf->readpos = 0;
		buf->b_flags = 0;
	}
	spin_lock_irqsave(&s->qlock, flags);
	list_add_tail(&buf->list, &q->list);
	q->buffers++;
	q->length += s->buf_size;
	q->bytesused += buf->bytesused - buf->readpos;
	spin_unlock_irqrestore(&s->qlock, flags);
}

struct cx18_buffer *cx18_dequeue(struct cx18_stream *s, struct cx18_queue *q)
{
	struct cx18_buffer *buf = NULL;
	unsigned long flags = 0;

	spin_lock_irqsave(&s->qlock, flags);
	if (!list_empty(&q->list)) {
		buf = list_entry(q->list.next, struct cx18_buffer, list);
		list_del_init(q->list.next);
		q->buffers--;
		q->length -= s->buf_size;
		q->bytesused -= buf->bytesused - buf->readpos;
	}
	spin_unlock_irqrestore(&s->qlock, flags);
	return buf;
}

struct cx18_buffer *cx18_queue_get_buf_irq(struct cx18_stream *s, u32 id,
	u32 bytesused)
{
	struct cx18 *cx = s->cx;
	struct list_head *p;

	spin_lock(&s->qlock);
	list_for_each(p, &s->q_free.list) {
		struct cx18_buffer *buf =
			list_entry(p, struct cx18_buffer, list);

		if (buf->id != id)
			continue;
		buf->bytesused = bytesused;
		/* the transport buffers are handled differently,
		   they are not moved to the full queue */
		if (s->type != CX18_ENC_STREAM_TYPE_TS) {
			s->q_free.buffers--;
			s->q_free.length -= s->buf_size;
			s->q_full.buffers++;
			s->q_full.length += s->buf_size;
			s->q_full.bytesused += buf->bytesused;
			list_move_tail(&buf->list, &s->q_full.list);
		}
		spin_unlock(&s->qlock);
		return buf;
	}
	spin_unlock(&s->qlock);
	CX18_ERR("Cannot find buffer %d for stream %s\n", id, s->name);
	return NULL;
}

/* Move all buffers of a queue to q_free, while flushing the buffers */
static void cx18_queue_flush(struct cx18_stream *s, struct cx18_queue *q)
{
	unsigned long flags;
	struct cx18_buffer *buf;

	if (q == &s->q_free)
		return;

	spin_lock_irqsave(&s->qlock, flags);
	while (!list_empty(&q->list)) {
		buf = list_entry(q->list.next, struct cx18_buffer, list);
		list_move_tail(q->list.next, &s->q_free.list);
		buf->bytesused = buf->readpos = buf->b_flags = 0;
		s->q_free.buffers++;
		s->q_free.length += s->buf_size;
	}
	cx18_queue_init(q);
	spin_unlock_irqrestore(&s->qlock, flags);
}

void cx18_flush_queues(struct cx18_stream *s)
{
	cx18_queue_flush(s, &s->q_io);
	cx18_queue_flush(s, &s->q_full);
}

int cx18_stream_alloc(struct cx18_stream *s)
{
	struct cx18 *cx = s->cx;
	int i;

	if (s->buffers == 0)
		return 0;

	CX18_DEBUG_INFO("Allocate %s stream: %d x %d buffers (%dkB total)\n",
		s->name, s->buffers, s->buf_size,
		s->buffers * s->buf_size / 1024);

	if (((char __iomem *)&cx->scb->cpu_mdl[cx->mdl_offset + s->buffers] -
				(char __iomem *)cx->scb) > SCB_RESERVED_SIZE) {
		unsigned bufsz = (((char __iomem *)cx->scb) + SCB_RESERVED_SIZE -
					((char __iomem *)cx->scb->cpu_mdl));

		CX18_ERR("Too many buffers, cannot fit in SCB area\n");
		CX18_ERR("Max buffers = %zd\n",
			bufsz / sizeof(struct cx18_mdl));
		return -ENOMEM;
	}

	s->mdl_offset = cx->mdl_offset;

	/* allocate stream buffers. Initially all buffers are in q_free. */
	for (i = 0; i < s->buffers; i++) {
		struct cx18_buffer *buf = kzalloc(sizeof(struct cx18_buffer),
						GFP_KERNEL|__GFP_NOWARN);

		if (buf == NULL)
			break;
		buf->buf = kmalloc(s->buf_size, GFP_KERNEL|__GFP_NOWARN);
		if (buf->buf == NULL) {
			kfree(buf);
			break;
		}
		buf->id = cx->buffer_id++;
		INIT_LIST_HEAD(&buf->list);
		buf->dma_handle = pci_map_single(s->cx->dev,
				buf->buf, s->buf_size, s->dma);
		cx18_buf_sync_for_cpu(s, buf);
		cx18_enqueue(s, buf, &s->q_free);
	}
	if (i == s->buffers) {
		cx->mdl_offset += s->buffers;
		return 0;
	}
	CX18_ERR("Couldn't allocate buffers for %s stream\n", s->name);
	cx18_stream_free(s);
	return -ENOMEM;
}

void cx18_stream_free(struct cx18_stream *s)
{
	struct cx18_buffer *buf;

	/* move all buffers to q_free */
	cx18_flush_queues(s);

	/* empty q_free */
	while ((buf = cx18_dequeue(s, &s->q_free))) {
		pci_unmap_single(s->cx->dev, buf->dma_handle,
				s->buf_size, s->dma);
		kfree(buf->buf);
		kfree(buf);
	}
}