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 #include "em28xx.h"
  10
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/hardirq.h>
  14 #include <linux/init.h>
  15 #include <linux/usb.h>
  16
  17 #include "em28xx-v4l.h"
  18
  19 /* ------------------------------------------------------------------ */
  20
  21 static int vbi_queue_setup(struct vb2_queue *vq,
  22                            unsigned int *nbuffers, unsigned int *nplanes,
  23                            unsigned int sizes[], struct device *alloc_devs[])
  24 {
  25         struct em28xx *dev = vb2_get_drv_priv(vq);
  26         struct em28xx_v4l2 *v4l2 = dev->v4l2;
  27         unsigned long size = v4l2->vbi_width * v4l2->vbi_height * 2;
  28
  29         if (*nbuffers < 2)
  30                 *nbuffers = 2;
  31
  32         if (*nplanes) {
  33                 if (sizes[0] < size)
  34                         return -EINVAL;
  35                 size = sizes[0];
  36         }
  37
  38         *nplanes = 1;
  39         sizes[0] = size;
  40
  41         return 0;
  42 }
  43
  44 static int vbi_buffer_prepare(struct vb2_buffer *vb)
  45 {
  46         struct em28xx        *dev  = vb2_get_drv_priv(vb->vb2_queue);
  47         struct em28xx_v4l2   *v4l2 = dev->v4l2;
  48         unsigned long        size;
  49
  50         size = v4l2->vbi_width * v4l2->vbi_height * 2;
  51
  52         if (vb2_plane_size(vb, 0) < size) {
  53                 dev_info(&dev->intf->dev,
  54                          "%s data will not fit into plane (%lu < %lu)\n",
  55                          __func__, vb2_plane_size(vb, 0), size);
  56                 return -EINVAL;
  57         }
  58         vb2_set_plane_payload(vb, 0, size);
  59
  60         return 0;
  61 }
  62
  63 static void
  64 vbi_buffer_queue(struct vb2_buffer *vb)
  65 {
  66         struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
  67         struct em28xx *dev = vb2_get_drv_priv(vb->vb2_queue);
  68         struct em28xx_buffer *buf =
  69                 container_of(vbuf, struct em28xx_buffer, vb);
  70         struct em28xx_dmaqueue *vbiq = &dev->vbiq;
  71         unsigned long flags = 0;
  72
  73         buf->mem = vb2_plane_vaddr(vb, 0);
  74         buf->length = vb2_plane_size(vb, 0);
  75
  76         spin_lock_irqsave(&dev->slock, flags);
  77         list_add_tail(&buf->list, &vbiq->active);
  78         spin_unlock_irqrestore(&dev->slock, flags);
  79 }
  80
  81 const struct vb2_ops em28xx_vbi_qops = {
  82         .queue_setup    = vbi_queue_setup,
  83         .buf_prepare    = vbi_buffer_prepare,
  84         .buf_queue      = vbi_buffer_queue,
  85         .start_streaming = em28xx_start_analog_streaming,
  86         .stop_streaming = em28xx_stop_vbi_streaming,
  87 };