sound/soc/atmel/atmel-pcm.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * at91-pcm.h - ALSA PCM interface for the Atmel AT91 SoC.
   4  *
   5  *  Copyright (C) 2005 SAN People
   6  *  Copyright (C) 2008 Atmel
   7  *
   8  * Authors: Sedji Gaouaou <sedji.gaouaou@atmel.com>
   9  *
  10  * Based on at91-pcm. by:
  11  * Frank Mandarino <fmandarino@endrelia.com>
  12  * Copyright 2006 Endrelia Technologies Inc.
  13  *
  14  * Based on pxa2xx-pcm.c by:
  15  *
  16  * Author:      Nicolas Pitre
  17  * Created:     Nov 30, 2004
  18  * Copyright:   (C) 2004 MontaVista Software, Inc.
  19  */
  20
  21 #ifndef _ATMEL_PCM_H
  22 #define _ATMEL_PCM_H
  23
  24 #include <linux/atmel-ssc.h>
  25
  26 #define ATMEL_SSC_DMABUF_SIZE   (64 * 1024)
  27
  28 /*
  29  * Registers and status bits that are required by the PCM driver.
  30  */
  31 struct atmel_pdc_regs {
  32         unsigned int    xpr;            /* PDC recv/trans pointer */
  33         unsigned int    xcr;            /* PDC recv/trans counter */
  34         unsigned int    xnpr;           /* PDC next recv/trans pointer */
  35         unsigned int    xncr;           /* PDC next recv/trans counter */
  36         unsigned int    ptcr;           /* PDC transfer control */
  37 };
  38
  39 struct atmel_ssc_mask {
  40         u32     ssc_enable;             /* SSC recv/trans enable */
  41         u32     ssc_disable;            /* SSC recv/trans disable */
  42         u32     ssc_error;              /* SSC error conditions */
  43         u32     ssc_endx;               /* SSC ENDTX or ENDRX */
  44         u32     ssc_endbuf;             /* SSC TXBUFE or RXBUFF */
  45         u32     pdc_enable;             /* PDC recv/trans enable */
  46         u32     pdc_disable;            /* PDC recv/trans disable */
  47 };
  48
  49 /*
  50  * This structure, shared between the PCM driver and the interface,
  51  * contains all information required by the PCM driver to perform the
  52  * PDC DMA operation.  All fields except dma_intr_handler() are initialized
  53  * by the interface.  The dma_intr_handler() pointer is set by the PCM
  54  * driver and called by the interface SSC interrupt handler if it is
  55  * non-NULL.
  56  */
  57 struct atmel_pcm_dma_params {
  58         char *name;                     /* stream identifier */
  59         int pdc_xfer_size;              /* PDC counter increment in bytes */
  60         struct ssc_device *ssc;         /* SSC device for stream */
  61         struct atmel_pdc_regs *pdc;     /* PDC receive or transmit registers */
  62         struct atmel_ssc_mask *mask;    /* SSC & PDC status bits */
  63         struct snd_pcm_substream *substream;
  64         void (*dma_intr_handler)(u32, struct snd_pcm_substream *);
  65 };
  66
  67 /*
  68  * SSC register access (since ssc_writel() / ssc_readl() require literal name)
  69  */
  70 #define ssc_readx(base, reg)            (__raw_readl((base) + (reg)))
  71 #define ssc_writex(base, reg, value)    __raw_writel((value), (base) + (reg))
  72
  73 #if IS_ENABLED(CONFIG_SND_ATMEL_SOC_PDC)
  74 int atmel_pcm_pdc_platform_register(struct device *dev);
  75 #else
  76 static inline int atmel_pcm_pdc_platform_register(struct device *dev)
  77 {
  78         return 0;
  79 }
  80 #endif
  81
  82 #if IS_ENABLED(CONFIG_SND_ATMEL_SOC_DMA)
  83 int atmel_pcm_dma_platform_register(struct device *dev);
  84 #else
  85 static inline int atmel_pcm_dma_platform_register(struct device *dev)
  86 {
  87         return 0;
  88 }
  89 #endif
  90
  91 #endif /* _ATMEL_PCM_H */