xref: /linux/drivers/media/usb/em28xx/em28xx-vbi.c (revision 4f2c0a4acffbec01079c28f839422e64ddeff004)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // em28xx-vbi.c - VBI driver for em28xx
4 //
5 // Copyright (C) 2009 Devin Heitmueller <dheitmueller@kernellabs.com>
6 //
7 // This work was sponsored by EyeMagnet Limited.
8 
9 #include "em28xx.h"
10 
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/hardirq.h>
14 #include <linux/init.h>
15 #include <linux/usb.h>
16 
17 #include "em28xx-v4l.h"
18 
19 /* ------------------------------------------------------------------ */
20 
vbi_queue_setup(struct vb2_queue * vq,unsigned int * nbuffers,unsigned int * nplanes,unsigned int sizes[],struct device * alloc_devs[])21 static int vbi_queue_setup(struct vb2_queue *vq,
22 			   unsigned int *nbuffers, unsigned int *nplanes,
23 			   unsigned int sizes[], struct device *alloc_devs[])
24 {
25 	struct em28xx *dev = vb2_get_drv_priv(vq);
26 	struct em28xx_v4l2 *v4l2 = dev->v4l2;
27 	unsigned long size = v4l2->vbi_width * v4l2->vbi_height * 2;
28 
29 	if (*nbuffers < 2)
30 		*nbuffers = 2;
31 
32 	if (*nplanes) {
33 		if (sizes[0] < size)
34 			return -EINVAL;
35 		size = sizes[0];
36 	}
37 
38 	*nplanes = 1;
39 	sizes[0] = size;
40 
41 	return 0;
42 }
43 
vbi_buffer_prepare(struct vb2_buffer * vb)44 static int vbi_buffer_prepare(struct vb2_buffer *vb)
45 {
46 	struct em28xx        *dev  = vb2_get_drv_priv(vb->vb2_queue);
47 	struct em28xx_v4l2   *v4l2 = dev->v4l2;
48 	unsigned long        size;
49 
50 	size = v4l2->vbi_width * v4l2->vbi_height * 2;
51 
52 	if (vb2_plane_size(vb, 0) < size) {
53 		dev_info(&dev->intf->dev,
54 			 "%s data will not fit into plane (%lu < %lu)\n",
55 			 __func__, vb2_plane_size(vb, 0), size);
56 		return -EINVAL;
57 	}
58 	vb2_set_plane_payload(vb, 0, size);
59 
60 	return 0;
61 }
62 
63 static void
vbi_buffer_queue(struct vb2_buffer * vb)64 vbi_buffer_queue(struct vb2_buffer *vb)
65 {
66 	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
67 	struct em28xx *dev = vb2_get_drv_priv(vb->vb2_queue);
68 	struct em28xx_buffer *buf =
69 		container_of(vbuf, struct em28xx_buffer, vb);
70 	struct em28xx_dmaqueue *vbiq = &dev->vbiq;
71 	unsigned long flags = 0;
72 
73 	buf->mem = vb2_plane_vaddr(vb, 0);
74 	buf->length = vb2_plane_size(vb, 0);
75 
76 	spin_lock_irqsave(&dev->slock, flags);
77 	list_add_tail(&buf->list, &vbiq->active);
78 	spin_unlock_irqrestore(&dev->slock, flags);
79 }
80 
81 const struct vb2_ops em28xx_vbi_qops = {
82 	.queue_setup    = vbi_queue_setup,
83 	.buf_prepare    = vbi_buffer_prepare,
84 	.buf_queue      = vbi_buffer_queue,
85 	.start_streaming = em28xx_start_analog_streaming,
86 	.stop_streaming = em28xx_stop_vbi_streaming,
87 	.wait_prepare   = vb2_ops_wait_prepare,
88 	.wait_finish    = vb2_ops_wait_finish,
89 };
90