xref: /openbmc/linux/sound/soc/atmel/atmel-pcm.h (revision 3213486f)
1 /*
2  * at91-pcm.h - ALSA PCM interface for the Atmel AT91 SoC.
3  *
4  *  Copyright (C) 2005 SAN People
5  *  Copyright (C) 2008 Atmel
6  *
7  * Authors: Sedji Gaouaou <sedji.gaouaou@atmel.com>
8  *
9  * Based on at91-pcm. by:
10  * Frank Mandarino <fmandarino@endrelia.com>
11  * Copyright 2006 Endrelia Technologies Inc.
12  *
13  * Based on pxa2xx-pcm.c by:
14  *
15  * Author:	Nicolas Pitre
16  * Created:	Nov 30, 2004
17  * Copyright:	(C) 2004 MontaVista Software, Inc.
18  *
19  * This program is free software; you can redistribute it and/or modify
20  * it under the terms of the GNU General Public License as published by
21  * the Free Software Foundation; either version 2 of the License, or
22  * (at your option) any later version.
23  *
24  * This program is distributed in the hope that it will be useful,
25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
27  * GNU General Public License for more details.
28  *
29  * You should have received a copy of the GNU General Public License
30  * along with this program; if not, write to the Free Software
31  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
32  */
33 
34 #ifndef _ATMEL_PCM_H
35 #define _ATMEL_PCM_H
36 
37 #include <linux/atmel-ssc.h>
38 
39 #define ATMEL_SSC_DMABUF_SIZE	(64 * 1024)
40 
41 /*
42  * Registers and status bits that are required by the PCM driver.
43  */
44 struct atmel_pdc_regs {
45 	unsigned int	xpr;		/* PDC recv/trans pointer */
46 	unsigned int	xcr;		/* PDC recv/trans counter */
47 	unsigned int	xnpr;		/* PDC next recv/trans pointer */
48 	unsigned int	xncr;		/* PDC next recv/trans counter */
49 	unsigned int	ptcr;		/* PDC transfer control */
50 };
51 
52 struct atmel_ssc_mask {
53 	u32	ssc_enable;		/* SSC recv/trans enable */
54 	u32	ssc_disable;		/* SSC recv/trans disable */
55 	u32	ssc_error;		/* SSC error conditions */
56 	u32	ssc_endx;		/* SSC ENDTX or ENDRX */
57 	u32	ssc_endbuf;		/* SSC TXBUFE or RXBUFF */
58 	u32	pdc_enable;		/* PDC recv/trans enable */
59 	u32	pdc_disable;		/* PDC recv/trans disable */
60 };
61 
62 /*
63  * This structure, shared between the PCM driver and the interface,
64  * contains all information required by the PCM driver to perform the
65  * PDC DMA operation.  All fields except dma_intr_handler() are initialized
66  * by the interface.  The dma_intr_handler() pointer is set by the PCM
67  * driver and called by the interface SSC interrupt handler if it is
68  * non-NULL.
69  */
70 struct atmel_pcm_dma_params {
71 	char *name;			/* stream identifier */
72 	int pdc_xfer_size;		/* PDC counter increment in bytes */
73 	struct ssc_device *ssc;		/* SSC device for stream */
74 	struct atmel_pdc_regs *pdc;	/* PDC receive or transmit registers */
75 	struct atmel_ssc_mask *mask;	/* SSC & PDC status bits */
76 	struct snd_pcm_substream *substream;
77 	void (*dma_intr_handler)(u32, struct snd_pcm_substream *);
78 };
79 
80 /*
81  * SSC register access (since ssc_writel() / ssc_readl() require literal name)
82  */
83 #define ssc_readx(base, reg)            (__raw_readl((base) + (reg)))
84 #define ssc_writex(base, reg, value)    __raw_writel((value), (base) + (reg))
85 
86 #if IS_ENABLED(CONFIG_SND_ATMEL_SOC_PDC)
87 int atmel_pcm_pdc_platform_register(struct device *dev);
88 void atmel_pcm_pdc_platform_unregister(struct device *dev);
89 #else
90 static inline int atmel_pcm_pdc_platform_register(struct device *dev)
91 {
92 	return 0;
93 }
94 static inline void atmel_pcm_pdc_platform_unregister(struct device *dev)
95 {
96 }
97 #endif
98 
99 #if IS_ENABLED(CONFIG_SND_ATMEL_SOC_DMA)
100 int atmel_pcm_dma_platform_register(struct device *dev);
101 void atmel_pcm_dma_platform_unregister(struct device *dev);
102 #else
103 static inline int atmel_pcm_dma_platform_register(struct device *dev)
104 {
105 	return 0;
106 }
107 static inline void atmel_pcm_dma_platform_unregister(struct device *dev)
108 {
109 }
110 #endif
111 
112 #endif /* _ATMEL_PCM_H */
113