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 */