/*

   *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>

   *                   Takashi Iwai <tiwai@suse.de>
   * 
   *  Generic memory allocators
   *
   *
   *   This program is free software; you can redistribute it and/or modify
   *   it under the terms of the GNU General Public License as published by
   *   the Free Software Foundation; either version 2 of the License, or
   *   (at your option) any later version.
   *
   *   This program is distributed in the hope that it will be useful,
   *   but WITHOUT ANY WARRANTY; without even the implied warranty of
   *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *   GNU General Public License for more details.
   *
   *   You should have received a copy of the GNU General Public License
   *   along with this program; if not, write to the Free Software
   *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
   *
   */
  
  #ifndef __SOUND_MEMALLOC_H
  #define __SOUND_MEMALLOC_H
  
  struct device;
  
  /*
   * buffer device info
   */
  struct snd_dma_device {
  	int type;			/* SNDRV_DMA_TYPE_XXX */
  	struct device *dev;		/* generic device */
  };
  
  #ifndef snd_dma_pci_data
  #define snd_dma_pci_data(pci)	(&(pci)->dev)
  #define snd_dma_isa_data()	NULL

  #define snd_dma_continuous_data(x)	((struct device *)(unsigned long)(x))
  #endif
  
  
  /*
   * buffer types
   */
  #define SNDRV_DMA_TYPE_UNKNOWN		0	/* not defined */
  #define SNDRV_DMA_TYPE_CONTINUOUS	1	/* continuous no-DMA memory */
  #define SNDRV_DMA_TYPE_DEV		2	/* generic device continuous */

  #ifdef CONFIG_SND_DMA_SGBUF

  #define SNDRV_DMA_TYPE_DEV_SG		3	/* generic device SG-buffer */

  #else
  #define SNDRV_DMA_TYPE_DEV_SG	SNDRV_DMA_TYPE_DEV /* no SG-buf support */
  #endif

  
  /*
   * info for buffer allocation
   */
  struct snd_dma_buffer {
  	struct snd_dma_device dev;	/* device type */
  	unsigned char *area;	/* virtual pointer */
  	dma_addr_t addr;	/* physical address */
  	size_t bytes;		/* buffer size in bytes */
  	void *private_data;	/* private for allocator; don't touch */
  };

  #ifdef CONFIG_SND_DMA_SGBUF

  /*
   * Scatter-Gather generic device pages
   */

  void *snd_malloc_sgbuf_pages(struct device *device,
  			     size_t size, struct snd_dma_buffer *dmab,
  			     size_t *res_size);
  int snd_free_sgbuf_pages(struct snd_dma_buffer *dmab);

  struct snd_sg_page {
  	void *buf;
  	dma_addr_t addr;
  };
  
  struct snd_sg_buf {
  	int size;	/* allocated byte size */
  	int pages;	/* allocated pages */
  	int tblsize;	/* allocated table size */
  	struct snd_sg_page *table;	/* address table */
  	struct page **page_table;	/* page table (for vmap/vunmap) */
  	struct device *dev;
  };
  
  /*
   * return the pages matching with the given byte size
   */
  static inline unsigned int snd_sgbuf_aligned_pages(size_t size)
  {
  	return (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
  }
  
  /*
   * return the physical address at the corresponding offset
   */
  static inline dma_addr_t snd_sgbuf_get_addr(struct snd_sg_buf *sgbuf, size_t offset)
  {

  	dma_addr_t addr = sgbuf->table[offset >> PAGE_SHIFT].addr;
  	addr &= PAGE_MASK;
  	return addr + offset % PAGE_SIZE;

  }

  /*
   * return the virtual address at the corresponding offset
   */
  static inline void *snd_sgbuf_get_ptr(struct snd_sg_buf *sgbuf, size_t offset)
  {
  	return sgbuf->table[offset >> PAGE_SHIFT].buf + offset % PAGE_SIZE;
  }

  #endif /* CONFIG_SND_DMA_SGBUF */

  
  /* allocate/release a buffer */
  int snd_dma_alloc_pages(int type, struct device *dev, size_t size,
  			struct snd_dma_buffer *dmab);
  int snd_dma_alloc_pages_fallback(int type, struct device *dev, size_t size,
                                   struct snd_dma_buffer *dmab);
  void snd_dma_free_pages(struct snd_dma_buffer *dmab);
  
  /* buffer-preservation managements */
  
  #define snd_dma_pci_buf_id(pci)	(((unsigned int)(pci)->vendor << 16) | (pci)->device)
  
  size_t snd_dma_get_reserved_buf(struct snd_dma_buffer *dmab, unsigned int id);
  int snd_dma_reserve_buf(struct snd_dma_buffer *dmab, unsigned int id);
  
  /* basic memory allocation functions */

  void *snd_malloc_pages(size_t size, gfp_t gfp_flags);

  void snd_free_pages(void *ptr, size_t size);
  
  #endif /* __SOUND_MEMALLOC_H */