drivers/media/usb/em28xx/em28xx-vbi.c

   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 };