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 "em28xx.h"
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/hardirq.h>
  29 #include <linux/init.h>
  30 #include <linux/usb.h>
  31
  32 #include "em28xx-v4l.h"
  33
  34 /* ------------------------------------------------------------------ */
  35
  36 static int vbi_queue_setup(struct vb2_queue *vq,
  37                            unsigned int *nbuffers, unsigned int *nplanes,
  38                            unsigned int sizes[], struct device *alloc_devs[])
  39 {
  40         struct em28xx *dev = vb2_get_drv_priv(vq);
  41         struct em28xx_v4l2 *v4l2 = dev->v4l2;
  42         unsigned long size = v4l2->vbi_width * v4l2->vbi_height * 2;
  43
  44         if (*nbuffers < 2)
  45                 *nbuffers = 2;
  46
  47         if (*nplanes) {
  48                 if (sizes[0] < size)
  49                         return -EINVAL;
  50                 size = sizes[0];
  51         }
  52
  53         *nplanes = 1;
  54         sizes[0] = size;
  55
  56         return 0;
  57 }
  58
  59 static int vbi_buffer_prepare(struct vb2_buffer *vb)
  60 {
  61         struct em28xx        *dev  = vb2_get_drv_priv(vb->vb2_queue);
  62         struct em28xx_v4l2   *v4l2 = dev->v4l2;
  63         unsigned long        size;
  64
  65         size = v4l2->vbi_width * v4l2->vbi_height * 2;
  66
  67         if (vb2_plane_size(vb, 0) < size) {
  68                 dev_info(&dev->intf->dev,
  69                          "%s data will not fit into plane (%lu < %lu)\n",
  70                          __func__, vb2_plane_size(vb, 0), size);
  71                 return -EINVAL;
  72         }
  73         vb2_set_plane_payload(vb, 0, size);
  74
  75         return 0;
  76 }
  77
  78 static void
  79 vbi_buffer_queue(struct vb2_buffer *vb)
  80 {
  81         struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
  82         struct em28xx *dev = vb2_get_drv_priv(vb->vb2_queue);
  83         struct em28xx_buffer *buf =
  84                 container_of(vbuf, struct em28xx_buffer, vb);
  85         struct em28xx_dmaqueue *vbiq = &dev->vbiq;
  86         unsigned long flags = 0;
  87
  88         buf->mem = vb2_plane_vaddr(vb, 0);
  89         buf->length = vb2_plane_size(vb, 0);
  90
  91         spin_lock_irqsave(&dev->slock, flags);
  92         list_add_tail(&buf->list, &vbiq->active);
  93         spin_unlock_irqrestore(&dev->slock, flags);
  94 }
  95
  96 const struct vb2_ops em28xx_vbi_qops = {
  97         .queue_setup    = vbi_queue_setup,
  98         .buf_prepare    = vbi_buffer_prepare,
  99         .buf_queue      = vbi_buffer_queue,
 100         .start_streaming = em28xx_start_analog_streaming,
 101         .stop_streaming = em28xx_stop_vbi_streaming,
 102         .wait_prepare   = vb2_ops_wait_prepare,
 103         .wait_finish    = vb2_ops_wait_finish,
 104 };