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_byte_reg_read(void *context, unsigned int reg,
11					unsigned int *val)
12{
13	struct slim_device *sdev = context;
14	int v;
15
16	v = slim_readb(sdev, reg);
17
18	if (v < 0)
19		return v;
20
21	*val = v;
22
23	return 0;
24}
25
26static int regmap_slimbus_byte_reg_write(void *context, unsigned int reg,
27					 unsigned int val)
28{
29	struct slim_device *sdev = context;
30
31	return slim_writeb(sdev, reg, val);
32}
33
34static struct regmap_bus regmap_slimbus_bus = {
35	.reg_write = regmap_slimbus_byte_reg_write,
36	.reg_read = regmap_slimbus_byte_reg_read,
37	.reg_format_endian_default = REGMAP_ENDIAN_LITTLE,
38	.val_format_endian_default = REGMAP_ENDIAN_LITTLE,
39};
40
41static const struct regmap_bus *regmap_get_slimbus(struct slim_device *slim,
42					const struct regmap_config *config)
43{
44	if (config->val_bits == 8 && config->reg_bits == 8)
45		return &regmap_slimbus_bus;
46
47	return ERR_PTR(-ENOTSUPP);
48}
49
50struct regmap *__regmap_init_slimbus(struct slim_device *slimbus,
51				     const struct regmap_config *config,
52				     struct lock_class_key *lock_key,
53				     const char *lock_name)
54{
55	const struct regmap_bus *bus = regmap_get_slimbus(slimbus, config);
56
57	if (IS_ERR(bus))
58		return ERR_CAST(bus);
59
60	return __regmap_init(&slimbus->dev, bus, &slimbus->dev, config,
61			     lock_key, lock_name);
62}
63EXPORT_SYMBOL_GPL(__regmap_init_slimbus);
64
65struct regmap *__devm_regmap_init_slimbus(struct slim_device *slimbus,
66					  const struct regmap_config *config,
67					  struct lock_class_key *lock_key,
68					  const char *lock_name)
69{
70	const struct regmap_bus *bus = regmap_get_slimbus(slimbus, config);
71
72	if (IS_ERR(bus))
73		return ERR_CAST(bus);
74
75	return __devm_regmap_init(&slimbus->dev, bus, &slimbus, config,
76				  lock_key, lock_name);
77}
78EXPORT_SYMBOL_GPL(__devm_regmap_init_slimbus);
79
80MODULE_LICENSE("GPL v2");