soc/atmel/atmel-pcm.h

0001 /* SPDX-License-Identifier: GPL-2.0-or-later */
0002 /*
0003  * at91-pcm.h - ALSA PCM interface for the Atmel AT91 SoC.
0004  *
0005  *  Copyright (C) 2005 SAN People
0006  *  Copyright (C) 2008 Atmel
0007  *
0008  * Authors: Sedji Gaouaou <sedji.gaouaou@atmel.com>
0009  *
0010  * Based on at91-pcm. by:
0011  * Frank Mandarino <fmandarino@endrelia.com>
0012  * Copyright 2006 Endrelia Technologies Inc.
0013  *
0014  * Based on pxa2xx-pcm.c by:
0015  *
0016  * Author:  Nicolas Pitre
0017  * Created: Nov 30, 2004
0018  * Copyright:   (C) 2004 MontaVista Software, Inc.
0019  */
0020
0021 #ifndef _ATMEL_PCM_H
0022 #define _ATMEL_PCM_H
0023
0024 #include <linux/atmel-ssc.h>
0025
0026 #define ATMEL_SSC_DMABUF_SIZE   (64 * 1024)
0027
0028 /*
0029  * Registers and status bits that are required by the PCM driver.
0030  */
0031 struct atmel_pdc_regs {
0032     unsigned int    xpr;        /* PDC recv/trans pointer */
0033     unsigned int    xcr;        /* PDC recv/trans counter */
0034     unsigned int    xnpr;       /* PDC next recv/trans pointer */
0035     unsigned int    xncr;       /* PDC next recv/trans counter */
0036     unsigned int    ptcr;       /* PDC transfer control */
0037 };
0038
0039 struct atmel_ssc_mask {
0040     u32 ssc_enable;     /* SSC recv/trans enable */
0041     u32 ssc_disable;        /* SSC recv/trans disable */
0042     u32 ssc_error;      /* SSC error conditions */
0043     u32 ssc_endx;       /* SSC ENDTX or ENDRX */
0044     u32 ssc_endbuf;     /* SSC TXBUFE or RXBUFF */
0045     u32 pdc_enable;     /* PDC recv/trans enable */
0046     u32 pdc_disable;        /* PDC recv/trans disable */
0047 };
0048
0049 /*
0050  * This structure, shared between the PCM driver and the interface,
0051  * contains all information required by the PCM driver to perform the
0052  * PDC DMA operation.  All fields except dma_intr_handler() are initialized
0053  * by the interface.  The dma_intr_handler() pointer is set by the PCM
0054  * driver and called by the interface SSC interrupt handler if it is
0055  * non-NULL.
0056  */
0057 struct atmel_pcm_dma_params {
0058     char *name;         /* stream identifier */
0059     int pdc_xfer_size;      /* PDC counter increment in bytes */
0060     struct ssc_device *ssc;     /* SSC device for stream */
0061     struct atmel_pdc_regs *pdc; /* PDC receive or transmit registers */
0062     struct atmel_ssc_mask *mask;    /* SSC & PDC status bits */
0063     struct snd_pcm_substream *substream;
0064     void (*dma_intr_handler)(u32, struct snd_pcm_substream *);
0065 };
0066
0067 /*
0068  * SSC register access (since ssc_writel() / ssc_readl() require literal name)
0069  */
0070 #define ssc_readx(base, reg)            (__raw_readl((base) + (reg)))
0071 #define ssc_writex(base, reg, value)    __raw_writel((value), (base) + (reg))
0072
0073 #if IS_ENABLED(CONFIG_SND_ATMEL_SOC_PDC)
0074 int atmel_pcm_pdc_platform_register(struct device *dev);
0075 #else
0076 static inline int atmel_pcm_pdc_platform_register(struct device *dev)
0077 {
0078     return 0;
0079 }
0080 #endif
0081
0082 #if IS_ENABLED(CONFIG_SND_ATMEL_SOC_DMA)
0083 int atmel_pcm_dma_platform_register(struct device *dev);
0084 #else
0085 static inline int atmel_pcm_dma_platform_register(struct device *dev)
0086 {
0087     return 0;
0088 }
0089 #endif
0090
0091 #endif /* _ATMEL_PCM_H */