tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Register map access API - SPI support
3 *
4 * Copyright 2011 Wolfson Microelectronics plc
5 *
6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/regmap.h>
14#include <linux/spi/spi.h>
15#include <linux/init.h>
16#include <linux/module.h>
17
18static int regmap_spi_write(void *context, const void *data, size_t count)
19{
20 struct device *dev = context;
21 struct spi_device *spi = to_spi_device(dev);
22
23 return spi_write(spi, data, count);
24}
25
26static int regmap_spi_gather_write(void *context,
27 const void *reg, size_t reg_len,
28 const void *val, size_t val_len)
29{
30 struct device *dev = context;
31 struct spi_device *spi = to_spi_device(dev);
32 struct spi_message m;
33 struct spi_transfer t[2] = { { .tx_buf = reg, .len = reg_len, },
34 { .tx_buf = val, .len = val_len, }, };
35
36 spi_message_init(&m);
37 spi_message_add_tail(&t[0], &m);
38 spi_message_add_tail(&t[1], &m);
39
40 return spi_sync(spi, &m);
41}
42
43static int regmap_spi_read(void *context,
44 const void *reg, size_t reg_size,
45 void *val, size_t val_size)
46{
47 struct device *dev = context;
48 struct spi_device *spi = to_spi_device(dev);
49
50 return spi_write_then_read(spi, reg, reg_size, val, val_size);
51}
52
53static struct regmap_bus regmap_spi = {
54 .write = regmap_spi_write,
55 .gather_write = regmap_spi_gather_write,
56 .read = regmap_spi_read,
57 .read_flag_mask = 0x80,
58};
59
60/**
61 * regmap_init_spi(): Initialise register map
62 *
63 * @spi: Device that will be interacted with
64 * @config: Configuration for register map
65 *
66 * The return value will be an ERR_PTR() on error or a valid pointer to
67 * a struct regmap.
68 */
69struct regmap *regmap_init_spi(struct spi_device *spi,
70 const struct regmap_config *config)
71{
72 return regmap_init(&spi->dev, ®map_spi, &spi->dev, config);
73}
74EXPORT_SYMBOL_GPL(regmap_init_spi);
75
76/**
77 * devm_regmap_init_spi(): Initialise register map
78 *
79 * @spi: Device that will be interacted with
80 * @config: Configuration for register map
81 *
82 * The return value will be an ERR_PTR() on error or a valid pointer
83 * to a struct regmap. The map will be automatically freed by the
84 * device management code.
85 */
86struct regmap *devm_regmap_init_spi(struct spi_device *spi,
87 const struct regmap_config *config)
88{
89 return devm_regmap_init(&spi->dev, ®map_spi, &spi->dev, config);
90}
91EXPORT_SYMBOL_GPL(devm_regmap_init_spi);
92
93MODULE_LICENSE("GPL");