1// SPDX-License-Identifier: GPL-2.0
 2// Copyright(c) 2015-17 Intel Corporation.
 3
 4#include <linux/device.h>
 5#include <linux/errno.h>
 6#include <linux/module.h>
 7#include <linux/regmap.h>
 8#include <linux/soundwire/sdw.h>
 9#include "internal.h"
10
11static int regmap_sdw_write(void *context, unsigned int reg, unsigned int val)
12{
13	struct device *dev = context;
14	struct sdw_slave *slave = dev_to_sdw_dev(dev);
15
16	return sdw_write_no_pm(slave, reg, val);
17}
18
19static int regmap_sdw_read(void *context, unsigned int reg, unsigned int *val)
20{
21	struct device *dev = context;
22	struct sdw_slave *slave = dev_to_sdw_dev(dev);
23	int read;
24
25	read = sdw_read_no_pm(slave, reg);
26	if (read < 0)
27		return read;
28
29	*val = read;
30	return 0;
31}
32
33static const struct regmap_bus regmap_sdw = {
34	.reg_read = regmap_sdw_read,
35	.reg_write = regmap_sdw_write,
36	.reg_format_endian_default = REGMAP_ENDIAN_LITTLE,
37	.val_format_endian_default = REGMAP_ENDIAN_LITTLE,
38};
39
40static int regmap_sdw_config_check(const struct regmap_config *config)
41{
42	/* All register are 8-bits wide as per MIPI Soundwire 1.0 Spec */
43	if (config->val_bits != 8)
44		return -ENOTSUPP;
45
46	/* Registers are 32 bits wide */
47	if (config->reg_bits != 32)
48		return -ENOTSUPP;
49
50	if (config->pad_bits != 0)
51		return -ENOTSUPP;
52
53	return 0;
54}
55
56struct regmap *__regmap_init_sdw(struct sdw_slave *sdw,
57				 const struct regmap_config *config,
58				 struct lock_class_key *lock_key,
59				 const char *lock_name)
60{
61	int ret;
62
63	ret = regmap_sdw_config_check(config);
64	if (ret)
65		return ERR_PTR(ret);
66
67	return __regmap_init(&sdw->dev, &regmap_sdw,
68			&sdw->dev, config, lock_key, lock_name);
69}
70EXPORT_SYMBOL_GPL(__regmap_init_sdw);
71
72struct regmap *__devm_regmap_init_sdw(struct sdw_slave *sdw,
73				      const struct regmap_config *config,
74				      struct lock_class_key *lock_key,
75				      const char *lock_name)
76{
77	int ret;
78
79	ret = regmap_sdw_config_check(config);
80	if (ret)
81		return ERR_PTR(ret);
82
83	return __devm_regmap_init(&sdw->dev, &regmap_sdw,
84			&sdw->dev, config, lock_key, lock_name);
85}
86EXPORT_SYMBOL_GPL(__devm_regmap_init_sdw);
87
88MODULE_DESCRIPTION("Regmap SoundWire Module");
89MODULE_LICENSE("GPL v2");