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 void *parg,
35 			   unsigned int *nbuffers, unsigned int *nplanes,
36 			   unsigned int sizes[], void *alloc_ctxs[])
37 {
38 	const struct v4l2_format *fmt = parg;
39 	struct em28xx *dev = vb2_get_drv_priv(vq);
40 	struct em28xx_v4l2 *v4l2 = dev->v4l2;
41 	unsigned long size;
42 
43 	if (fmt)
44 		size = fmt->fmt.pix.sizeimage;
45 	else
46 		size = v4l2->vbi_width * v4l2->vbi_height * 2;
47 
48 	if (0 == *nbuffers)
49 		*nbuffers = 32;
50 	if (*nbuffers < 2)
51 		*nbuffers = 2;
52 	if (*nbuffers > 32)
53 		*nbuffers = 32;
54 
55 	*nplanes = 1;
56 	sizes[0] = size;
57 
58 	return 0;
59 }
60 
61 static int vbi_buffer_prepare(struct vb2_buffer *vb)
62 {
63 	struct em28xx        *dev  = vb2_get_drv_priv(vb->vb2_queue);
64 	struct em28xx_v4l2   *v4l2 = dev->v4l2;
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(vb, 0, size);
75 
76 	return 0;
77 }
78 
79 static void
80 vbi_buffer_queue(struct vb2_buffer *vb)
81 {
82 	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
83 	struct em28xx *dev = vb2_get_drv_priv(vb->vb2_queue);
84 	struct em28xx_buffer *buf =
85 		container_of(vbuf, struct em28xx_buffer, vb);
86 	struct em28xx_dmaqueue *vbiq = &dev->vbiq;
87 	unsigned long flags = 0;
88 
89 	buf->mem = vb2_plane_vaddr(vb, 0);
90 	buf->length = vb2_plane_size(vb, 0);
91 
92 	spin_lock_irqsave(&dev->slock, flags);
93 	list_add_tail(&buf->list, &vbiq->active);
94 	spin_unlock_irqrestore(&dev->slock, flags);
95 }
96 
97 struct vb2_ops em28xx_vbi_qops = {
98 	.queue_setup    = vbi_queue_setup,
99 	.buf_prepare    = vbi_buffer_prepare,
100 	.buf_queue      = vbi_buffer_queue,
101 	.start_streaming = em28xx_start_analog_streaming,
102 	.stop_streaming = em28xx_stop_vbi_streaming,
103 	.wait_prepare   = vb2_ops_wait_prepare,
104 	.wait_finish    = vb2_ops_wait_finish,
105 };
106