1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
|
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2021 Analog Devices, Inc.
* Author: Cosmin Tanislav <cosmin.tanislav@analog.com>
*/
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/spi/spi.h>
#include <linux/iio/iio.h>
#include "adxl367.h"
#define ADXL367_SPI_WRITE_COMMAND 0x0A
#define ADXL367_SPI_READ_COMMAND 0x0B
#define ADXL367_SPI_FIFO_COMMAND 0x0D
struct adxl367_spi_state {
struct spi_device *spi;
struct spi_message reg_write_msg;
struct spi_transfer reg_write_xfer[2];
struct spi_message reg_read_msg;
struct spi_transfer reg_read_xfer[2];
struct spi_message fifo_msg;
struct spi_transfer fifo_xfer[2];
/*
* DMA (thus cache coherency maintenance) may require the
* transfer buffers live in their own cache lines.
*/
u8 reg_write_tx_buf[1] __aligned(IIO_DMA_MINALIGN);
u8 reg_read_tx_buf[2];
u8 fifo_tx_buf[1];
};
static int adxl367_read_fifo(void *context, __be16 *fifo_buf,
unsigned int fifo_entries)
{
struct adxl367_spi_state *st = context;
st->fifo_xfer[1].rx_buf = fifo_buf;
st->fifo_xfer[1].len = fifo_entries * sizeof(*fifo_buf);
return spi_sync(st->spi, &st->fifo_msg);
}
static int adxl367_read(void *context, const void *reg_buf, size_t reg_size,
void *val_buf, size_t val_size)
{
struct adxl367_spi_state *st = context;
u8 reg = ((const u8 *)reg_buf)[0];
st->reg_read_tx_buf[1] = reg;
st->reg_read_xfer[1].rx_buf = val_buf;
st->reg_read_xfer[1].len = val_size;
return spi_sync(st->spi, &st->reg_read_msg);
}
static int adxl367_write(void *context, const void *val_buf, size_t val_size)
{
struct adxl367_spi_state *st = context;
st->reg_write_xfer[1].tx_buf = val_buf;
st->reg_write_xfer[1].len = val_size;
return spi_sync(st->spi, &st->reg_write_msg);
}
static const struct regmap_bus adxl367_spi_regmap_bus = {
.read = adxl367_read,
.write = adxl367_write,
};
static const struct regmap_config adxl367_spi_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
};
static const struct adxl367_ops adxl367_spi_ops = {
.read_fifo = adxl367_read_fifo,
};
static int adxl367_spi_probe(struct spi_device *spi)
{
struct adxl367_spi_state *st;
struct regmap *regmap;
st = devm_kzalloc(&spi->dev, sizeof(*st), GFP_KERNEL);
if (!st)
return -ENOMEM;
st->spi = spi;
/*
* Xfer: [XFR1] [ XFR2 ]
* Master: 0x0A ADDR DATA0 DATA1 ... DATAN
* Slave: .... ..........................
*/
st->reg_write_tx_buf[0] = ADXL367_SPI_WRITE_COMMAND;
st->reg_write_xfer[0].tx_buf = st->reg_write_tx_buf;
st->reg_write_xfer[0].len = sizeof(st->reg_write_tx_buf);
spi_message_init_with_transfers(&st->reg_write_msg,
st->reg_write_xfer, 2);
/*
* Xfer: [ XFR1 ] [ XFR2 ]
* Master: 0x0B ADDR .....................
* Slave: ......... DATA0 DATA1 ... DATAN
*/
st->reg_read_tx_buf[0] = ADXL367_SPI_READ_COMMAND;
st->reg_read_xfer[0].tx_buf = st->reg_read_tx_buf;
st->reg_read_xfer[0].len = sizeof(st->reg_read_tx_buf);
spi_message_init_with_transfers(&st->reg_read_msg,
st->reg_read_xfer, 2);
/*
* Xfer: [XFR1] [ XFR2 ]
* Master: 0x0D .....................
* Slave: .... DATA0 DATA1 ... DATAN
*/
st->fifo_tx_buf[0] = ADXL367_SPI_FIFO_COMMAND;
st->fifo_xfer[0].tx_buf = st->fifo_tx_buf;
st->fifo_xfer[0].len = sizeof(st->fifo_tx_buf);
spi_message_init_with_transfers(&st->fifo_msg, st->fifo_xfer, 2);
regmap = devm_regmap_init(&spi->dev, &adxl367_spi_regmap_bus, st,
&adxl367_spi_regmap_config);
if (IS_ERR(regmap))
return PTR_ERR(regmap);
return adxl367_probe(&spi->dev, &adxl367_spi_ops, st, regmap, spi->irq);
}
static const struct spi_device_id adxl367_spi_id[] = {
{ "adxl367", 0 },
{ },
};
MODULE_DEVICE_TABLE(spi, adxl367_spi_id);
static const struct of_device_id adxl367_of_match[] = {
{ .compatible = "adi,adxl367" },
{ },
};
MODULE_DEVICE_TABLE(of, adxl367_of_match);
static struct spi_driver adxl367_spi_driver = {
.driver = {
.name = "adxl367_spi",
.of_match_table = adxl367_of_match,
},
.probe = adxl367_spi_probe,
.id_table = adxl367_spi_id,
};
module_spi_driver(adxl367_spi_driver);
MODULE_IMPORT_NS(IIO_ADXL367);
MODULE_AUTHOR("Cosmin Tanislav <cosmin.tanislav@analog.com>");
MODULE_DESCRIPTION("Analog Devices ADXL367 3-axis accelerometer SPI driver");
MODULE_LICENSE("GPL");
|