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,
  35                            unsigned int *nbuffers, unsigned int *nplanes,
  36                            unsigned int sizes[], struct device *alloc_devs[])
  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 };