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 static unsigned int vbibufs = 5;
  33 module_param(vbibufs, int, 0644);
  34 MODULE_PARM_DESC(vbibufs, "number of vbi buffers, range 2-32");
  35
  36 static unsigned int vbi_debug;
  37 module_param(vbi_debug, int, 0644);
  38 MODULE_PARM_DESC(vbi_debug, "enable debug messages [vbi]");
  39
  40 #define dprintk(level, fmt, arg...)     if (vbi_debug >= level) \
  41         printk(KERN_DEBUG "%s: " fmt, dev->core->name , ## arg)
  42
  43 /* ------------------------------------------------------------------ */
  44
  45 static int vbi_queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt,
  46                            unsigned int *nbuffers, unsigned int *nplanes,
  47                            unsigned int sizes[], void *alloc_ctxs[])
  48 {
  49         struct em28xx *dev = vb2_get_drv_priv(vq);
  50         unsigned long size;
  51
  52         if (fmt)
  53                 size = fmt->fmt.pix.sizeimage;
  54         else
  55                 size = dev->vbi_width * dev->vbi_height * 2;
  56
  57         if (0 == *nbuffers)
  58                 *nbuffers = 32;
  59         if (*nbuffers < 2)
  60                 *nbuffers = 2;
  61         if (*nbuffers > 32)
  62                 *nbuffers = 32;
  63
  64         *nplanes = 1;
  65         sizes[0] = size;
  66
  67         return 0;
  68 }
  69
  70 static int vbi_buffer_prepare(struct vb2_buffer *vb)
  71 {
  72         struct em28xx        *dev = vb2_get_drv_priv(vb->vb2_queue);
  73         struct em28xx_buffer *buf = container_of(vb, struct em28xx_buffer, vb);
  74         unsigned long        size;
  75
  76         size = dev->vbi_width * dev->vbi_height * 2;
  77
  78         if (vb2_plane_size(vb, 0) < size) {
  79                 printk(KERN_INFO "%s data will not fit into plane (%lu < %lu)\n",
  80                        __func__, vb2_plane_size(vb, 0), size);
  81                 return -EINVAL;
  82         }
  83         vb2_set_plane_payload(&buf->vb, 0, size);
  84
  85         return 0;
  86 }
  87
  88 static void
  89 vbi_buffer_queue(struct vb2_buffer *vb)
  90 {
  91         struct em28xx *dev = vb2_get_drv_priv(vb->vb2_queue);
  92         struct em28xx_buffer *buf = container_of(vb, struct em28xx_buffer, vb);
  93         struct em28xx_dmaqueue *vbiq = &dev->vbiq;
  94         unsigned long flags = 0;
  95
  96         buf->mem = vb2_plane_vaddr(vb, 0);
  97         buf->length = vb2_plane_size(vb, 0);
  98
  99         spin_lock_irqsave(&dev->slock, flags);
 100         list_add_tail(&buf->list, &vbiq->active);
 101         spin_unlock_irqrestore(&dev->slock, flags);
 102 }
 103
 104
 105 struct vb2_ops em28xx_vbi_qops = {
 106         .queue_setup    = vbi_queue_setup,
 107         .buf_prepare    = vbi_buffer_prepare,
 108         .buf_queue      = vbi_buffer_queue,
 109         .start_streaming = em28xx_start_analog_streaming,
 110         .stop_streaming = em28xx_stop_vbi_streaming,
 111         .wait_prepare   = vb2_ops_wait_prepare,
 112         .wait_finish    = vb2_ops_wait_finish,
 113 };