1// SPDX-License-Identifier: GPL-2.0
2//
3// Register map access API - Memory region
4//
5// This is intended for testing only
6//
7// Copyright (c) 2023, Arm Ltd
8
9#include <linux/clk.h>
10#include <linux/err.h>
11#include <linux/io.h>
12#include <linux/module.h>
13#include <linux/regmap.h>
14#include <linux/slab.h>
15#include <linux/swab.h>
16
17#include "internal.h"
18
19static int regmap_ram_write(void *context, unsigned int reg, unsigned int val)
20{
21 struct regmap_ram_data *data = context;
22
23 data->vals[reg] = val;
24 data->written[reg] = true;
25
26 return 0;
27}
28
29static int regmap_ram_read(void *context, unsigned int reg, unsigned int *val)
30{
31 struct regmap_ram_data *data = context;
32
33 *val = data->vals[reg];
34 data->read[reg] = true;
35
36 return 0;
37}
38
39static void regmap_ram_free_context(void *context)
40{
41 struct regmap_ram_data *data = context;
42
43 kfree(objp: data->vals);
44 kfree(objp: data->read);
45 kfree(objp: data->written);
46 kfree(objp: data);
47}
48
49static const struct regmap_bus regmap_ram = {
50 .fast_io = true,
51 .reg_write = regmap_ram_write,
52 .reg_read = regmap_ram_read,
53 .free_context = regmap_ram_free_context,
54};
55
56struct regmap *__regmap_init_ram(const struct regmap_config *config,
57 struct regmap_ram_data *data,
58 struct lock_class_key *lock_key,
59 const char *lock_name)
60{
61 struct regmap *map;
62
63 if (!config->max_register) {
64 pr_crit("No max_register specified for RAM regmap\n");
65 return ERR_PTR(error: -EINVAL);
66 }
67
68 data->read = kcalloc(n: config->max_register + 1, size: sizeof(bool),
69 GFP_KERNEL);
70 if (!data->read)
71 return ERR_PTR(error: -ENOMEM);
72
73 data->written = kcalloc(n: config->max_register + 1, size: sizeof(bool),
74 GFP_KERNEL);
75 if (!data->written)
76 return ERR_PTR(error: -ENOMEM);
77
78 map = __regmap_init(NULL, bus: &regmap_ram, bus_context: data, config,
79 lock_key, lock_name);
80
81 return map;
82}
83EXPORT_SYMBOL_GPL(__regmap_init_ram);
84
85MODULE_LICENSE("GPL v2");
86

source code of linux/drivers/base/regmap/regmap-ram.c