LXR linux/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
  31static unsigned int vbibufs = 5;
  32module_param(vbibufs, int, 0644);
  33MODULE_PARM_DESC(vbibufs, "number of vbi buffers, range 2-32");
  34
  35static unsigned int vbi_debug;
  36module_param(vbi_debug, int, 0644);
  37MODULE_PARM_DESC(vbi_debug, "enable debug messages [vbi]");
  38
  39#define dprintk(level, fmt, arg...)     if (vbi_debug >= level) \
  40        printk(KERN_DEBUG "%s: " fmt, dev->core->name , ## arg)
  41
  42/* ------------------------------------------------------------------ */
  43
  44static int vbi_queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt,
  45                           unsigned int *nbuffers, unsigned int *nplanes,
  46                           unsigned int sizes[], void *alloc_ctxs[])
  47{
  48        struct em28xx *dev = vb2_get_drv_priv(vq);
  49        unsigned long size;
  50
  51        if (fmt)
  52                size = fmt->fmt.pix.sizeimage;
  53        else
  54                size = dev->vbi_width * dev->vbi_height * 2;
  55
  56        if (0 == *nbuffers)
  57                *nbuffers = 32;
  58        if (*nbuffers < 2)
  59                *nbuffers = 2;
  60        if (*nbuffers > 32)
  61                *nbuffers = 32;
  62
  63        *nplanes = 1;
  64        sizes[0] = size;
  65
  66        return 0;
  67}
  68
  69static int vbi_buffer_prepare(struct vb2_buffer *vb)
  70{
  71        struct em28xx        *dev = vb2_get_drv_priv(vb->vb2_queue);
  72        struct em28xx_buffer *buf = container_of(vb, struct em28xx_buffer, vb);
  73        unsigned long        size;
  74
  75        size = dev->vbi_width * dev->vbi_height * 2;
  76
  77        if (vb2_plane_size(vb, 0) < size) {
  78                printk(KERN_INFO "%s data will not fit into plane (%lu < %lu)\n",
  79                       __func__, vb2_plane_size(vb, 0), size);
  80                return -EINVAL;
  81        }
  82        vb2_set_plane_payload(&buf->vb, 0, size);
  83
  84        return 0;
  85}
  86
  87static void
  88vbi_buffer_queue(struct vb2_buffer *vb)
  89{
  90        struct em28xx *dev = vb2_get_drv_priv(vb->vb2_queue);
  91        struct em28xx_buffer *buf = container_of(vb, struct em28xx_buffer, vb);
  92        struct em28xx_dmaqueue *vbiq = &dev->vbiq;
  93        unsigned long flags = 0;
  94
  95        buf->mem = vb2_plane_vaddr(vb, 0);
  96        buf->length = vb2_plane_size(vb, 0);
  97
  98        spin_lock_irqsave(&dev->slock, flags);
  99        list_add_tail(&buf->list, &vbiq->active);
 100        spin_unlock_irqrestore(&dev->slock, flags);
 101}
 102
 103
 104struct vb2_ops em28xx_vbi_qops = {
 105        .queue_setup    = vbi_queue_setup,
 106        .buf_prepare    = vbi_buffer_prepare,
 107        .buf_queue      = vbi_buffer_queue,
 108        .start_streaming = em28xx_start_analog_streaming,
 109        .stop_streaming = em28xx_stop_vbi_streaming,
 110        .wait_prepare   = vb2_ops_wait_prepare,
 111        .wait_finish    = vb2_ops_wait_finish,
 112};
 113