atmel-pcm.h

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/*
 * at91-pcm.h - ALSA PCM interface for the Atmel AT91 SoC.
 *
 *  Copyright (C) 2005 SAN People
 *  Copyright (C) 2008 Atmel
 *
 * Authors: Sedji Gaouaou <[email protected]>
 *
 * Based on at91-pcm. by:
 * Frank Mandarino <[email protected]>
 * Copyright 2006 Endrelia Technologies Inc.
 *
 * Based on pxa2xx-pcm.c by:
 *
 * Author:  Nicolas Pitre
 * Created: Nov 30, 2004
 * Copyright:   (C) 2004 MontaVista Software, Inc.
 *
 * 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 _ATMEL_PCM_H
#define _ATMEL_PCM_H

#include <linux/atmel-ssc.h>

/*
 * Registers and status bits that are required by the PCM driver.
 */
struct atmel_pdc_regs {
    unsigned int    xpr;        /* PDC recv/trans pointer */
    unsigned int    xcr;        /* PDC recv/trans counter */
    unsigned int    xnpr;       /* PDC next recv/trans pointer */
    unsigned int    xncr;       /* PDC next recv/trans counter */
    unsigned int    ptcr;       /* PDC transfer control */
};

struct atmel_ssc_mask {
    u32 ssc_enable;     /* SSC recv/trans enable */
    u32 ssc_disable;        /* SSC recv/trans disable */
    u32 ssc_endx;       /* SSC ENDTX or ENDRX */
    u32 ssc_endbuf;     /* SSC TXBUFE or RXBUFF */
    u32 pdc_enable;     /* PDC recv/trans enable */
    u32 pdc_disable;        /* PDC recv/trans disable */
};

/*
 * This structure, shared between the PCM driver and the interface,
 * contains all information required by the PCM driver to perform the
 * PDC DMA operation.  All fields except dma_intr_handler() are initialized
 * by the interface.  The dma_intr_handler() pointer is set by the PCM
 * driver and called by the interface SSC interrupt handler if it is
 * non-NULL.
 */
struct atmel_pcm_dma_params {
    char *name;         /* stream identifier */
    int pdc_xfer_size;      /* PDC counter increment in bytes */
    struct ssc_device *ssc;     /* SSC device for stream */
    struct atmel_pdc_regs *pdc; /* PDC receive or transmit registers */
    struct atmel_ssc_mask *mask;    /* SSC & PDC status bits */
    struct snd_pcm_substream *substream;
    void (*dma_intr_handler)(u32, struct snd_pcm_substream *);
};

/*
 * SSC register access (since ssc_writel() / ssc_readl() require literal name)
 */
#define ssc_readx(base, reg)            (__raw_readl((base) + (reg)))
#define ssc_writex(base, reg, value)    __raw_writel((value), (base) + (reg))

#endif /* _ATMEL_PCM_H */