drivers/media/video/ivtv/ivtv-queue.h

   1 /*
   2     buffer queues.
   3     Copyright (C) 2003-2004  Kevin Thayer <nufan_wfk at yahoo.com>
   4     Copyright (C) 2004  Chris Kennedy <c@groovy.org>
   5     Copyright (C) 2005-2007  Hans Verkuil <hverkuil@xs4all.nl>
   6
   7     This program is free software; you can redistribute it and/or modify
   8     it under the terms of the GNU General Public License as published by
   9     the Free Software Foundation; either version 2 of the License, or
  10     (at your option) any later version.
  11
  12     This program is distributed in the hope that it will be useful,
  13     but WITHOUT ANY WARRANTY; without even the implied warranty of
  14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15     GNU General Public License for more details.
  16
  17     You should have received a copy of the GNU General Public License
  18     along with this program; if not, write to the Free Software
  19     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #define IVTV_DMA_UNMAPPED       ((u32) -1)
  23 #define SLICED_VBI_PIO 1
  24
  25 /* ivtv_buffer utility functions */
  26
  27 static inline int ivtv_might_use_pio(struct ivtv_stream *s)
  28 {
  29         return s->dma == PCI_DMA_NONE || (SLICED_VBI_PIO && s->type == IVTV_ENC_STREAM_TYPE_VBI);
  30 }
  31
  32 static inline int ivtv_use_pio(struct ivtv_stream *s)
  33 {
  34         struct ivtv *itv = s->itv;
  35
  36         return s->dma == PCI_DMA_NONE ||
  37             (SLICED_VBI_PIO && s->type == IVTV_ENC_STREAM_TYPE_VBI && itv->vbi.sliced_in->service_set);
  38 }
  39
  40 static inline int ivtv_might_use_dma(struct ivtv_stream *s)
  41 {
  42         return s->dma != PCI_DMA_NONE;
  43 }
  44
  45 static inline int ivtv_use_dma(struct ivtv_stream *s)
  46 {
  47         return !ivtv_use_pio(s);
  48 }
  49
  50 static inline void ivtv_buf_sync_for_cpu(struct ivtv_stream *s, struct ivtv_buffer *buf)
  51 {
  52         if (ivtv_use_dma(s))
  53                 pci_dma_sync_single_for_cpu(s->itv->dev, buf->dma_handle,
  54                                 s->buf_size + 256, s->dma);
  55 }
  56
  57 static inline void ivtv_buf_sync_for_device(struct ivtv_stream *s, struct ivtv_buffer *buf)
  58 {
  59         if (ivtv_use_dma(s))
  60                 pci_dma_sync_single_for_device(s->itv->dev, buf->dma_handle,
  61                                 s->buf_size + 256, s->dma);
  62 }
  63
  64 int ivtv_buf_copy_from_user(struct ivtv_stream *s, struct ivtv_buffer *buf, const char __user *src, int copybytes);
  65 void ivtv_buf_swap(struct ivtv_buffer *buf);
  66
  67 /* ivtv_queue utility functions */
  68 void ivtv_queue_init(struct ivtv_queue *q);
  69 void ivtv_enqueue(struct ivtv_stream *s, struct ivtv_buffer *buf, struct ivtv_queue *q);
  70 struct ivtv_buffer *ivtv_dequeue(struct ivtv_stream *s, struct ivtv_queue *q);
  71 int ivtv_queue_move(struct ivtv_stream *s, struct ivtv_queue *from, struct ivtv_queue *steal,
  72                     struct ivtv_queue *to, int needed_bytes);
  73 void ivtv_flush_queues(struct ivtv_stream *s);
  74
  75 /* ivtv_stream utility functions */
  76 int ivtv_stream_alloc(struct ivtv_stream *s);
  77 void ivtv_stream_free(struct ivtv_stream *s);
  78
  79 static inline void ivtv_stream_sync_for_cpu(struct ivtv_stream *s)
  80 {
  81         if (ivtv_use_dma(s))
  82                 pci_dma_sync_single_for_cpu(s->itv->dev, s->SG_handle,
  83                         sizeof(struct ivtv_SG_element) * s->buffers, PCI_DMA_TODEVICE);
  84 }
  85
  86 static inline void ivtv_stream_sync_for_device(struct ivtv_stream *s)
  87 {
  88         if (ivtv_use_dma(s))
  89                 pci_dma_sync_single_for_device(s->itv->dev, s->SG_handle,
  90                         sizeof(struct ivtv_SG_element) * s->buffers, PCI_DMA_TODEVICE);
  91 }