regmap-slimbus.c

 1// SPDX-License-Identifier: GPL-2.0
 2// Copyright (c) 2017, Linaro Ltd.
 3
 4#include <linux/regmap.h>
 5#include <linux/slimbus.h>
 6#include <linux/module.h>
 7
 8#include "internal.h"
 9
10static int regmap_slimbus_write(void *context, const void *data, size_t count)
11{
12	struct slim_device *sdev = context;
13
14	return slim_write(sdev, *(u16 *)data, count - 2, (u8 *)data + 2);
15}
16
17static int regmap_slimbus_read(void *context, const void *reg, size_t reg_size,
18			       void *val, size_t val_size)
19{
20	struct slim_device *sdev = context;
21
22	return slim_read(sdev, *(u16 *)reg, val_size, val);
23}
24
25static const struct regmap_bus regmap_slimbus_bus = {
26	.write = regmap_slimbus_write,
27	.read = regmap_slimbus_read,
28	.reg_format_endian_default = REGMAP_ENDIAN_LITTLE,
29	.val_format_endian_default = REGMAP_ENDIAN_LITTLE,
30};
31
32static const struct regmap_bus *regmap_get_slimbus(struct slim_device *slim,
33					const struct regmap_config *config)
34{
35	if (config->val_bits == 8 && config->reg_bits == 16)
36		return &regmap_slimbus_bus;
37
38	return ERR_PTR(-ENOTSUPP);
39}
40
41struct regmap *__regmap_init_slimbus(struct slim_device *slimbus,
42				     const struct regmap_config *config,
43				     struct lock_class_key *lock_key,
44				     const char *lock_name)
45{
46	const struct regmap_bus *bus = regmap_get_slimbus(slimbus, config);
47
48	if (IS_ERR(bus))
49		return ERR_CAST(bus);
50
51	return __regmap_init(&slimbus->dev, bus, slimbus, config, lock_key, lock_name);
52}
53EXPORT_SYMBOL_GPL(__regmap_init_slimbus);
54
55struct regmap *__devm_regmap_init_slimbus(struct slim_device *slimbus,
56					  const struct regmap_config *config,
57					  struct lock_class_key *lock_key,
58					  const char *lock_name)
59{
60	const struct regmap_bus *bus = regmap_get_slimbus(slimbus, config);
61
62	if (IS_ERR(bus))
63		return ERR_CAST(bus);
64
65	return __devm_regmap_init(&slimbus->dev, bus, slimbus, config, lock_key, lock_name);
66}
67EXPORT_SYMBOL_GPL(__devm_regmap_init_slimbus);
68
69MODULE_DESCRIPTION("Register map access API - SLIMbus support");
70MODULE_LICENSE("GPL v2");