1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * i2sbus driver -- interface register definitions
4  *
5  * Copyright 2006 Johannes Berg <johannes@sipsolutions.net>
6  */
7 #ifndef __I2SBUS_INTERFACE_H
8 #define __I2SBUS_INTERFACE_H
9 
10 /* i2s bus control registers, at least what we know about them */
11 
12 #define __PAD(m,n) u8 __pad##m[n]
13 #define _PAD(line, n) __PAD(line, n)
14 #define PAD(n) _PAD(__LINE__, (n))
15 struct i2s_interface_regs {
16 	__le32 intr_ctl;	/* 0x00 */
17 	PAD(12);
18 	__le32 serial_format;	/* 0x10 */
19 	PAD(12);
20 	__le32 codec_msg_out;	/* 0x20 */
21 	PAD(12);
22 	__le32 codec_msg_in;	/* 0x30 */
23 	PAD(12);
24 	__le32 frame_count;	/* 0x40 */
25 	PAD(12);
26 	__le32 frame_match;	/* 0x50 */
27 	PAD(12);
28 	__le32 data_word_sizes;	/* 0x60 */
29 	PAD(12);
30 	__le32 peak_level_sel;	/* 0x70 */
31 	PAD(12);
32 	__le32 peak_level_in0;	/* 0x80 */
33 	PAD(12);
34 	__le32 peak_level_in1;	/* 0x90 */
35 	PAD(12);
36 	/* total size: 0x100 bytes */
37 } __packed;
38 
39 /* interrupt register is just a bitfield with
40  * interrupt enable and pending bits */
41 #define I2S_REG_INTR_CTL		0x00
42 #	define I2S_INT_FRAME_COUNT		(1<<31)
43 #	define I2S_PENDING_FRAME_COUNT		(1<<30)
44 #	define I2S_INT_MESSAGE_FLAG		(1<<29)
45 #	define I2S_PENDING_MESSAGE_FLAG		(1<<28)
46 #	define I2S_INT_NEW_PEAK			(1<<27)
47 #	define I2S_PENDING_NEW_PEAK		(1<<26)
48 #	define I2S_INT_CLOCKS_STOPPED		(1<<25)
49 #	define I2S_PENDING_CLOCKS_STOPPED	(1<<24)
50 #	define I2S_INT_EXTERNAL_SYNC_ERROR	(1<<23)
51 #	define I2S_PENDING_EXTERNAL_SYNC_ERROR	(1<<22)
52 #	define I2S_INT_EXTERNAL_SYNC_OK		(1<<21)
53 #	define I2S_PENDING_EXTERNAL_SYNC_OK	(1<<20)
54 #	define I2S_INT_NEW_SAMPLE_RATE		(1<<19)
55 #	define I2S_PENDING_NEW_SAMPLE_RATE	(1<<18)
56 #	define I2S_INT_STATUS_FLAG		(1<<17)
57 #	define I2S_PENDING_STATUS_FLAG		(1<<16)
58 
59 /* serial format register is more interesting :)
60  * It contains:
61  *  - clock source
62  *  - MClk divisor
63  *  - SClk divisor
64  *  - SClk master flag
65  *  - serial format (sony, i2s 64x, i2s 32x, dav, silabs)
66  *  - external sample frequency interrupt (don't understand)
67  *  - external sample frequency
68  */
69 #define I2S_REG_SERIAL_FORMAT		0x10
70 /* clock source. You get either 18.432, 45.1584 or 49.1520 MHz */
71 #	define I2S_SF_CLOCK_SOURCE_SHIFT	30
72 #	define I2S_SF_CLOCK_SOURCE_MASK		(3<<I2S_SF_CLOCK_SOURCE_SHIFT)
73 #	define I2S_SF_CLOCK_SOURCE_18MHz	(0<<I2S_SF_CLOCK_SOURCE_SHIFT)
74 #	define I2S_SF_CLOCK_SOURCE_45MHz	(1<<I2S_SF_CLOCK_SOURCE_SHIFT)
75 #	define I2S_SF_CLOCK_SOURCE_49MHz	(2<<I2S_SF_CLOCK_SOURCE_SHIFT)
76 /* also, let's define the exact clock speeds here, in Hz */
77 #define I2S_CLOCK_SPEED_18MHz	18432000
78 #define I2S_CLOCK_SPEED_45MHz	45158400
79 #define I2S_CLOCK_SPEED_49MHz	49152000
80 /* MClk is the clock that drives the codec, usually called its 'system clock'.
81  * It is derived by taking only every 'divisor' tick of the clock.
82  */
83 #	define I2S_SF_MCLKDIV_SHIFT		24
84 #	define I2S_SF_MCLKDIV_MASK		(0x1F<<I2S_SF_MCLKDIV_SHIFT)
85 #	define I2S_SF_MCLKDIV_1			(0x14<<I2S_SF_MCLKDIV_SHIFT)
86 #	define I2S_SF_MCLKDIV_3			(0x13<<I2S_SF_MCLKDIV_SHIFT)
87 #	define I2S_SF_MCLKDIV_5			(0x12<<I2S_SF_MCLKDIV_SHIFT)
88 #	define I2S_SF_MCLKDIV_14		(0x0E<<I2S_SF_MCLKDIV_SHIFT)
89 #	define I2S_SF_MCLKDIV_OTHER(div)	(((div/2-1)<<I2S_SF_MCLKDIV_SHIFT)&I2S_SF_MCLKDIV_MASK)
i2s_sf_mclkdiv(int div,int * out)90 static inline int i2s_sf_mclkdiv(int div, int *out)
91 {
92 	int d;
93 
94 	switch(div) {
95 	case 1: *out |= I2S_SF_MCLKDIV_1; return 0;
96 	case 3: *out |= I2S_SF_MCLKDIV_3; return 0;
97 	case 5: *out |= I2S_SF_MCLKDIV_5; return 0;
98 	case 14: *out |= I2S_SF_MCLKDIV_14; return 0;
99 	default:
100 		if (div%2) return -1;
101 		d = div/2-1;
102 		if (d == 0x14 || d == 0x13 || d == 0x12 || d == 0x0E)
103 			return -1;
104 		*out |= I2S_SF_MCLKDIV_OTHER(div);
105 		return 0;
106 	}
107 }
108 /* SClk is the clock that drives the i2s wire bus. Note that it is
109  * derived from the MClk above by taking only every 'divisor' tick
110  * of MClk.
111  */
112 #	define I2S_SF_SCLKDIV_SHIFT		20
113 #	define I2S_SF_SCLKDIV_MASK		(0xF<<I2S_SF_SCLKDIV_SHIFT)
114 #	define I2S_SF_SCLKDIV_1			(8<<I2S_SF_SCLKDIV_SHIFT)
115 #	define I2S_SF_SCLKDIV_3			(9<<I2S_SF_SCLKDIV_SHIFT)
116 #	define I2S_SF_SCLKDIV_OTHER(div)	(((div/2-1)<<I2S_SF_SCLKDIV_SHIFT)&I2S_SF_SCLKDIV_MASK)
i2s_sf_sclkdiv(int div,int * out)117 static inline int i2s_sf_sclkdiv(int div, int *out)
118 {
119 	int d;
120 
121 	switch(div) {
122 	case 1: *out |= I2S_SF_SCLKDIV_1; return 0;
123 	case 3: *out |= I2S_SF_SCLKDIV_3; return 0;
124 	default:
125 		if (div%2) return -1;
126 		d = div/2-1;
127 		if (d == 8 || d == 9) return -1;
128 		*out |= I2S_SF_SCLKDIV_OTHER(div);
129 		return 0;
130 	}
131 }
132 #	define I2S_SF_SCLK_MASTER		(1<<19)
133 /* serial format is the way the data is put to the i2s wire bus */
134 #	define I2S_SF_SERIAL_FORMAT_SHIFT	16
135 #	define I2S_SF_SERIAL_FORMAT_MASK	(7<<I2S_SF_SERIAL_FORMAT_SHIFT)
136 #	define I2S_SF_SERIAL_FORMAT_SONY	(0<<I2S_SF_SERIAL_FORMAT_SHIFT)
137 #	define I2S_SF_SERIAL_FORMAT_I2S_64X	(1<<I2S_SF_SERIAL_FORMAT_SHIFT)
138 #	define I2S_SF_SERIAL_FORMAT_I2S_32X	(2<<I2S_SF_SERIAL_FORMAT_SHIFT)
139 #	define I2S_SF_SERIAL_FORMAT_I2S_DAV	(4<<I2S_SF_SERIAL_FORMAT_SHIFT)
140 #	define I2S_SF_SERIAL_FORMAT_I2S_SILABS	(5<<I2S_SF_SERIAL_FORMAT_SHIFT)
141 /* unknown */
142 #	define I2S_SF_EXT_SAMPLE_FREQ_INT_SHIFT	12
143 #	define I2S_SF_EXT_SAMPLE_FREQ_INT_MASK	(0xF<<I2S_SF_SAMPLE_FREQ_INT_SHIFT)
144 /* probably gives external frequency? */
145 #	define I2S_SF_EXT_SAMPLE_FREQ_MASK	0xFFF
146 
147 /* used to send codec messages, but how isn't clear */
148 #define I2S_REG_CODEC_MSG_OUT		0x20
149 
150 /* used to receive codec messages, but how isn't clear */
151 #define I2S_REG_CODEC_MSG_IN		0x30
152 
153 /* frame count reg isn't clear to me yet, but probably useful */
154 #define I2S_REG_FRAME_COUNT		0x40
155 
156 /* program to some value, and get interrupt if frame count reaches it */
157 #define I2S_REG_FRAME_MATCH		0x50
158 
159 /* this register describes how the bus transfers data */
160 #define I2S_REG_DATA_WORD_SIZES		0x60
161 /* number of interleaved input channels */
162 #	define I2S_DWS_NUM_CHANNELS_IN_SHIFT	24
163 #	define I2S_DWS_NUM_CHANNELS_IN_MASK	(0x1F<<I2S_DWS_NUM_CHANNELS_IN_SHIFT)
164 /* word size of input data */
165 #	define I2S_DWS_DATA_IN_SIZE_SHIFT	16
166 #	define I2S_DWS_DATA_IN_16BIT		(0<<I2S_DWS_DATA_IN_SIZE_SHIFT)
167 #	define I2S_DWS_DATA_IN_24BIT		(3<<I2S_DWS_DATA_IN_SIZE_SHIFT)
168 /* number of interleaved output channels */
169 #	define I2S_DWS_NUM_CHANNELS_OUT_SHIFT	8
170 #	define I2S_DWS_NUM_CHANNELS_OUT_MASK	(0x1F<<I2S_DWS_NUM_CHANNELS_OUT_SHIFT)
171 /* word size of output data */
172 #	define I2S_DWS_DATA_OUT_SIZE_SHIFT	0
173 #	define I2S_DWS_DATA_OUT_16BIT		(0<<I2S_DWS_DATA_OUT_SIZE_SHIFT)
174 #	define I2S_DWS_DATA_OUT_24BIT		(3<<I2S_DWS_DATA_OUT_SIZE_SHIFT)
175 
176 
177 /* unknown */
178 #define I2S_REG_PEAK_LEVEL_SEL		0x70
179 
180 /* unknown */
181 #define I2S_REG_PEAK_LEVEL_IN0		0x80
182 
183 /* unknown */
184 #define I2S_REG_PEAK_LEVEL_IN1		0x90
185 
186 #endif /* __I2SBUS_INTERFACE_H */
187