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,
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 = v4l2->vbi_width * v4l2->vbi_height * 2;
41 
42 	if (*nbuffers < 2)
43 		*nbuffers = 2;
44 
45 	if (*nplanes) {
46 		if (sizes[0] < size)
47 			return -EINVAL;
48 		size = sizes[0];
49 	}
50 
51 	*nplanes = 1;
52 	sizes[0] = size;
53 
54 	return 0;
55 }
56 
57 static int vbi_buffer_prepare(struct vb2_buffer *vb)
58 {
59 	struct em28xx        *dev  = vb2_get_drv_priv(vb->vb2_queue);
60 	struct em28xx_v4l2   *v4l2 = dev->v4l2;
61 	unsigned long        size;
62 
63 	size = v4l2->vbi_width * v4l2->vbi_height * 2;
64 
65 	if (vb2_plane_size(vb, 0) < size) {
66 		printk(KERN_INFO "%s data will not fit into plane (%lu < %lu)\n",
67 		       __func__, vb2_plane_size(vb, 0), size);
68 		return -EINVAL;
69 	}
70 	vb2_set_plane_payload(vb, 0, size);
71 
72 	return 0;
73 }
74 
75 static void
76 vbi_buffer_queue(struct vb2_buffer *vb)
77 {
78 	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
79 	struct em28xx *dev = vb2_get_drv_priv(vb->vb2_queue);
80 	struct em28xx_buffer *buf =
81 		container_of(vbuf, struct em28xx_buffer, vb);
82 	struct em28xx_dmaqueue *vbiq = &dev->vbiq;
83 	unsigned long flags = 0;
84 
85 	buf->mem = vb2_plane_vaddr(vb, 0);
86 	buf->length = vb2_plane_size(vb, 0);
87 
88 	spin_lock_irqsave(&dev->slock, flags);
89 	list_add_tail(&buf->list, &vbiq->active);
90 	spin_unlock_irqrestore(&dev->slock, flags);
91 }
92 
93 struct vb2_ops em28xx_vbi_qops = {
94 	.queue_setup    = vbi_queue_setup,
95 	.buf_prepare    = vbi_buffer_prepare,
96 	.buf_queue      = vbi_buffer_queue,
97 	.start_streaming = em28xx_start_analog_streaming,
98 	.stop_streaming = em28xx_stop_vbi_streaming,
99 	.wait_prepare   = vb2_ops_wait_prepare,
100 	.wait_finish    = vb2_ops_wait_finish,
101 };
102