1 /*
2    em28xx-vbi.c - VBI driver for em28xx
3 
4    Copyright (C) 2009 Devin Heitmueller <dheitmueller@kernellabs.com>
5 
6    This work was sponsored by EyeMagnet Limited.
7 
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 2 of the License, or
11    (at your option) any later version.
12 
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with this program; if not, write to the Free Software
20    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
21    02110-1301, USA.
22  */
23 
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <linux/hardirq.h>
27 #include <linux/init.h>
28 
29 #include "em28xx.h"
30 #include "em28xx-v4l.h"
31 
32 /* ------------------------------------------------------------------ */
33 
34 static int vbi_queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt,
35 			   unsigned int *nbuffers, unsigned int *nplanes,
36 			   unsigned int sizes[], void *alloc_ctxs[])
37 {
38 	struct em28xx *dev = vb2_get_drv_priv(vq);
39 	struct em28xx_v4l2 *v4l2 = dev->v4l2;
40 	unsigned long size;
41 
42 	if (fmt)
43 		size = fmt->fmt.pix.sizeimage;
44 	else
45 		size = v4l2->vbi_width * v4l2->vbi_height * 2;
46 
47 	if (0 == *nbuffers)
48 		*nbuffers = 32;
49 	if (*nbuffers < 2)
50 		*nbuffers = 2;
51 	if (*nbuffers > 32)
52 		*nbuffers = 32;
53 
54 	*nplanes = 1;
55 	sizes[0] = size;
56 
57 	return 0;
58 }
59 
60 static int vbi_buffer_prepare(struct vb2_buffer *vb)
61 {
62 	struct em28xx        *dev  = vb2_get_drv_priv(vb->vb2_queue);
63 	struct em28xx_v4l2   *v4l2 = dev->v4l2;
64 	struct em28xx_buffer *buf  = container_of(vb, struct em28xx_buffer, vb);
65 	unsigned long        size;
66 
67 	size = v4l2->vbi_width * v4l2->vbi_height * 2;
68 
69 	if (vb2_plane_size(vb, 0) < size) {
70 		printk(KERN_INFO "%s data will not fit into plane (%lu < %lu)\n",
71 		       __func__, vb2_plane_size(vb, 0), size);
72 		return -EINVAL;
73 	}
74 	vb2_set_plane_payload(&buf->vb, 0, size);
75 
76 	return 0;
77 }
78 
79 static void
80 vbi_buffer_queue(struct vb2_buffer *vb)
81 {
82 	struct em28xx *dev = vb2_get_drv_priv(vb->vb2_queue);
83 	struct em28xx_buffer *buf = container_of(vb, struct em28xx_buffer, vb);
84 	struct em28xx_dmaqueue *vbiq = &dev->vbiq;
85 	unsigned long flags = 0;
86 
87 	buf->mem = vb2_plane_vaddr(vb, 0);
88 	buf->length = vb2_plane_size(vb, 0);
89 
90 	spin_lock_irqsave(&dev->slock, flags);
91 	list_add_tail(&buf->list, &vbiq->active);
92 	spin_unlock_irqrestore(&dev->slock, flags);
93 }
94 
95 struct vb2_ops em28xx_vbi_qops = {
96 	.queue_setup    = vbi_queue_setup,
97 	.buf_prepare    = vbi_buffer_prepare,
98 	.buf_queue      = vbi_buffer_queue,
99 	.start_streaming = em28xx_start_analog_streaming,
100 	.stop_streaming = em28xx_stop_vbi_streaming,
101 	.wait_prepare   = vb2_ops_wait_prepare,
102 	.wait_finish    = vb2_ops_wait_finish,
103 };
104