1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2015 MediaTek Inc.
4 * Author: Andrew-CT Chen <andrew-ct.chen@mediatek.com>
5 */
6
7#include <linux/device.h>
8#include <linux/module.h>
9#include <linux/mod_devicetable.h>
10#include <linux/io.h>
11#include <linux/nvmem-provider.h>
12#include <linux/platform_device.h>
13
14struct mtk_efuse_priv {
15	void __iomem *base;
16};
17
18static int mtk_reg_read(void *context,
19			unsigned int reg, void *_val, size_t bytes)
20{
21	struct mtk_efuse_priv *priv = context;
22	u32 *val = _val;
23	int i = 0, words = bytes / 4;
24
25	while (words--)
26		*val++ = readl(priv->base + reg + (i++ * 4));
27
28	return 0;
29}
30
31static int mtk_efuse_probe(struct platform_device *pdev)
32{
33	struct device *dev = &pdev->dev;
34	struct resource *res;
35	struct nvmem_device *nvmem;
36	struct nvmem_config econfig = {};
37	struct mtk_efuse_priv *priv;
38
39	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
40	if (!priv)
41		return -ENOMEM;
42
43	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
44	priv->base = devm_ioremap_resource(dev, res);
45	if (IS_ERR(priv->base))
46		return PTR_ERR(priv->base);
47
48	econfig.stride = 4;
49	econfig.word_size = 4;
50	econfig.reg_read = mtk_reg_read;
51	econfig.size = resource_size(res);
52	econfig.priv = priv;
53	econfig.dev = dev;
54	nvmem = devm_nvmem_register(dev, &econfig);
55
56	return PTR_ERR_OR_ZERO(nvmem);
57}
58
59static const struct of_device_id mtk_efuse_of_match[] = {
60	{ .compatible = "mediatek,mt8173-efuse",},
61	{ .compatible = "mediatek,efuse",},
62	{/* sentinel */},
63};
64MODULE_DEVICE_TABLE(of, mtk_efuse_of_match);
65
66static struct platform_driver mtk_efuse_driver = {
67	.probe = mtk_efuse_probe,
68	.driver = {
69		.name = "mediatek,efuse",
70		.of_match_table = mtk_efuse_of_match,
71	},
72};
73
74static int __init mtk_efuse_init(void)
75{
76	int ret;
77
78	ret = platform_driver_register(&mtk_efuse_driver);
79	if (ret) {
80		pr_err("Failed to register efuse driver\n");
81		return ret;
82	}
83
84	return 0;
85}
86
87static void __exit mtk_efuse_exit(void)
88{
89	return platform_driver_unregister(&mtk_efuse_driver);
90}
91
92subsys_initcall(mtk_efuse_init);
93module_exit(mtk_efuse_exit);
94
95MODULE_AUTHOR("Andrew-CT Chen <andrew-ct.chen@mediatek.com>");
96MODULE_DESCRIPTION("Mediatek EFUSE driver");
97MODULE_LICENSE("GPL v2");
98