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

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // em28xx-vbi.c - VBI driver for em28xx
   4 //
   5 // Copyright (C) 2009 Devin Heitmueller <dheitmueller@kernellabs.com>
   6 //
   7 // This work was sponsored by EyeMagnet Limited.
   8 //
   9 // This program is free software; you can redistribute it and/or modify
  10 // it under the terms of the GNU General Public License as published by
  11 // the Free Software Foundation; either version 2 of the License, or
  12 // (at your option) any later version.
  13 //
  14 // This program is distributed in the hope that it will be useful,
  15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 // GNU General Public License for more details.
  18
  19 #include "em28xx.h"
  20
  21 #include <linux/kernel.h>
  22 #include <linux/module.h>
  23 #include <linux/hardirq.h>
  24 #include <linux/init.h>
  25 #include <linux/usb.h>
  26
  27 #include "em28xx-v4l.h"
  28
  29 /* ------------------------------------------------------------------ */
  30
  31 static int vbi_queue_setup(struct vb2_queue *vq,
  32                            unsigned int *nbuffers, unsigned int *nplanes,
  33                            unsigned int sizes[], struct device *alloc_devs[])
  34 {
  35         struct em28xx *dev = vb2_get_drv_priv(vq);
  36         struct em28xx_v4l2 *v4l2 = dev->v4l2;
  37         unsigned long size = v4l2->vbi_width * v4l2->vbi_height * 2;
  38
  39         if (*nbuffers < 2)
  40                 *nbuffers = 2;
  41
  42         if (*nplanes) {
  43                 if (sizes[0] < size)
  44                         return -EINVAL;
  45                 size = sizes[0];
  46         }
  47
  48         *nplanes = 1;
  49         sizes[0] = size;
  50
  51         return 0;
  52 }
  53
  54 static int vbi_buffer_prepare(struct vb2_buffer *vb)
  55 {
  56         struct em28xx        *dev  = vb2_get_drv_priv(vb->vb2_queue);
  57         struct em28xx_v4l2   *v4l2 = dev->v4l2;
  58         unsigned long        size;
  59
  60         size = v4l2->vbi_width * v4l2->vbi_height * 2;
  61
  62         if (vb2_plane_size(vb, 0) < size) {
  63                 dev_info(&dev->intf->dev,
  64                          "%s data will not fit into plane (%lu < %lu)\n",
  65                          __func__, vb2_plane_size(vb, 0), size);
  66                 return -EINVAL;
  67         }
  68         vb2_set_plane_payload(vb, 0, size);
  69
  70         return 0;
  71 }
  72
  73 static void
  74 vbi_buffer_queue(struct vb2_buffer *vb)
  75 {
  76         struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
  77         struct em28xx *dev = vb2_get_drv_priv(vb->vb2_queue);
  78         struct em28xx_buffer *buf =
  79                 container_of(vbuf, struct em28xx_buffer, vb);
  80         struct em28xx_dmaqueue *vbiq = &dev->vbiq;
  81         unsigned long flags = 0;
  82
  83         buf->mem = vb2_plane_vaddr(vb, 0);
  84         buf->length = vb2_plane_size(vb, 0);
  85
  86         spin_lock_irqsave(&dev->slock, flags);
  87         list_add_tail(&buf->list, &vbiq->active);
  88         spin_unlock_irqrestore(&dev->slock, flags);
  89 }
  90
  91 const struct vb2_ops em28xx_vbi_qops = {
  92         .queue_setup    = vbi_queue_setup,
  93         .buf_prepare    = vbi_buffer_prepare,
  94         .buf_queue      = vbi_buffer_queue,
  95         .start_streaming = em28xx_start_analog_streaming,
  96         .stop_streaming = em28xx_stop_vbi_streaming,
  97         .wait_prepare   = vb2_ops_wait_prepare,
  98         .wait_finish    = vb2_ops_wait_finish,
  99 };