sound/soc/at32/at32-pcm.h

   1 /* sound/soc/at32/at32-pcm.h
   2  * ASoC PCM interface for Atmel AT32 SoC
   3  *
   4  * Copyright (C) 2008 Long Range Systems
   5  *    Geoffrey Wossum <gwossum@acm.org>
   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 version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #ifndef __SOUND_SOC_AT32_AT32_PCM_H
  13 #define __SOUND_SOC_AT32_AT32_PCM_H __FILE__
  14
  15 #include <linux/atmel-ssc.h>
  16
  17
  18 /*
  19  * Registers and status bits that are required by the PCM driver
  20  * TODO: Is ptcr really used?
  21  */
  22 struct at32_pdc_regs {
  23         u32 xpr;                /* PDC RX/TX pointer */
  24         u32 xcr;                /* PDC RX/TX counter */
  25         u32 xnpr;               /* PDC next RX/TX pointer */
  26         u32 xncr;               /* PDC next RX/TX counter */
  27         u32 ptcr;               /* PDC transfer control */
  28 };
  29
  30
  31
  32 /*
  33  * SSC mask info
  34  */
  35 struct at32_ssc_mask {
  36         u32 ssc_enable;         /* SSC RX/TX enable */
  37         u32 ssc_disable;        /* SSC RX/TX disable */
  38         u32 ssc_endx;           /* SSC ENDTX or ENDRX */
  39         u32 ssc_endbuf;         /* SSC TXBUFF or RXBUFF */
  40         u32 pdc_enable;         /* PDC RX/TX enable */
  41         u32 pdc_disable;        /* PDC RX/TX disable */
  42 };
  43
  44
  45
  46 /*
  47  * This structure, shared between the PCM driver and the interface,
  48  * contains all information required by the PCM driver to perform the
  49  * PDC DMA operation.  All fields except dma_intr_handler() are initialized
  50  * by the interface.  The dms_intr_handler() pointer is set by the PCM
  51  * driver and called by the interface SSC interrupt handler if it is
  52  * non-NULL.
  53  */
  54 struct at32_pcm_dma_params {
  55         char *name;             /* stream identifier */
  56         int pdc_xfer_size;      /* PDC counter increment in bytes */
  57         struct ssc_device *ssc; /* SSC device for stream */
  58         struct at32_pdc_regs *pdc;      /* PDC register info */
  59         struct at32_ssc_mask *mask;     /* SSC mask info */
  60         struct snd_pcm_substream *substream;
  61         void (*dma_intr_handler) (u32, struct snd_pcm_substream *);
  62 };
  63
  64
  65
  66 /*
  67  * The AT32 ASoC platform driver
  68  */
  69 extern struct snd_soc_platform at32_soc_platform;
  70
  71
  72
  73 /*
  74  * SSC register access (since ssc_writel() / ssc_readl() require literal name)
  75  */
  76 #define ssc_readx(base, reg)            (__raw_readl((base) + (reg)))
  77 #define ssc_writex(base, reg, value)    __raw_writel((value), (base) + (reg))
  78
  79 #endif /* __SOUND_SOC_AT32_AT32_PCM_H */