summaryrefslogtreecommitdiff
path: root/drivers/base/regmap/regmap-raw-ram.c
blob: 69eabfb89eda1040b565e1241c5b87d357b0c843 (plain)
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
// SPDX-License-Identifier: GPL-2.0
//
// Register map access API - Memory region with raw access
//
// This is intended for testing only
//
// Copyright (c) 2023, Arm Ltd

#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/swab.h>

#include "internal.h"

static unsigned int decode_reg(enum regmap_endian endian, const void *reg)
{
	const u16 *r = reg;

	if (endian == REGMAP_ENDIAN_BIG)
		return be16_to_cpu(*r);
	else
		return le16_to_cpu(*r);
}

static int regmap_raw_ram_gather_write(void *context,
				       const void *reg, size_t reg_len,
				       const void *val, size_t val_len)
{
	struct regmap_ram_data *data = context;
	unsigned int r;
	u16 *our_buf = (u16 *)data->vals;
	int i;

	if (reg_len != 2)
		return -EINVAL;
	if (val_len % 2)
		return -EINVAL;

	r = decode_reg(data->reg_endian, reg);
	if (data->noinc_reg && data->noinc_reg(data, r)) {
		memcpy(&our_buf[r], val + val_len - 2, 2);
		data->written[r] = true;
	} else {
		memcpy(&our_buf[r], val, val_len);

		for (i = 0; i < val_len / 2; i++)
			data->written[r + i] = true;
	}
	
	return 0;
}

static int regmap_raw_ram_write(void *context, const void *data, size_t count)
{
	return regmap_raw_ram_gather_write(context, data, 2,
					   data + 2, count - 2);
}

static int regmap_raw_ram_read(void *context,
			       const void *reg, size_t reg_len,
			       void *val, size_t val_len)
{
	struct regmap_ram_data *data = context;
	unsigned int r;
	u16 *our_buf = (u16 *)data->vals;
	int i;

	if (reg_len != 2)
		return -EINVAL;
	if (val_len % 2)
		return -EINVAL;

	r = decode_reg(data->reg_endian, reg);
	if (data->noinc_reg && data->noinc_reg(data, r)) {
		for (i = 0; i < val_len; i += 2)
			memcpy(val + i, &our_buf[r], 2);
		data->read[r] = true;
	} else {
		memcpy(val, &our_buf[r], val_len);

		for (i = 0; i < val_len / 2; i++)
			data->read[r + i] = true;
	}

	return 0;
}

static void regmap_raw_ram_free_context(void *context)
{
	struct regmap_ram_data *data = context;

	kfree(data->vals);
	kfree(data->read);
	kfree(data->written);
	kfree(data);
}

static const struct regmap_bus regmap_raw_ram = {
	.fast_io = true,
	.write = regmap_raw_ram_write,
	.gather_write = regmap_raw_ram_gather_write,
	.read = regmap_raw_ram_read,
	.free_context = regmap_raw_ram_free_context,
};

struct regmap *__regmap_init_raw_ram(struct device *dev,
				     const struct regmap_config *config,
				     struct regmap_ram_data *data,
				     struct lock_class_key *lock_key,
				     const char *lock_name)
{
	struct regmap *map;

	if (config->reg_bits != 16)
		return ERR_PTR(-EINVAL);

	if (!config->max_register) {
		pr_crit("No max_register specified for RAM regmap\n");
		return ERR_PTR(-EINVAL);
	}

	data->read = kcalloc(config->max_register + 1, sizeof(bool),
			     GFP_KERNEL);
	if (!data->read)
		return ERR_PTR(-ENOMEM);

	data->written = kcalloc(config->max_register + 1, sizeof(bool),
				GFP_KERNEL);
	if (!data->written)
		return ERR_PTR(-ENOMEM);

	data->reg_endian = config->reg_format_endian;

	map = __regmap_init(dev, &regmap_raw_ram, data, config,
			    lock_key, lock_name);

	return map;
}
EXPORT_SYMBOL_GPL(__regmap_init_raw_ram);

MODULE_LICENSE("GPL v2");