1/*
2 * Copyright (c) 2015 MediaTek Inc.
3 * Author: Andrew-CT Chen <andrew-ct.chen@mediatek.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 */
14
15#include <linux/device.h>
16#include <linux/module.h>
17#include <linux/mod_devicetable.h>
18#include <linux/io.h>
19#include <linux/nvmem-provider.h>
20#include <linux/platform_device.h>
21
22struct mtk_efuse_priv {
23 void __iomem *base;
24};
25
26static int mtk_reg_read(void *context,
27 unsigned int reg, void *_val, size_t bytes)
28{
29 struct mtk_efuse_priv *priv = context;
30 u32 *val = _val;
31 int i = 0, words = bytes / 4;
32
33 while (words--)
34 *val++ = readl(priv->base + reg + (i++ * 4));
35
36 return 0;
37}
38
39static int mtk_reg_write(void *context,
40 unsigned int reg, void *_val, size_t bytes)
41{
42 struct mtk_efuse_priv *priv = context;
43 u32 *val = _val;
44 int i = 0, words = bytes / 4;
45
46 while (words--)
47 writel(*val++, priv->base + reg + (i++ * 4));
48
49 return 0;
50}
51
52static int mtk_efuse_probe(struct platform_device *pdev)
53{
54 struct device *dev = &pdev->dev;
55 struct resource *res;
56 struct nvmem_device *nvmem;
57 struct nvmem_config econfig = {};
58 struct mtk_efuse_priv *priv;
59
60 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
61 if (!priv)
62 return -ENOMEM;
63
64 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
65 priv->base = devm_ioremap_resource(dev, res);
66 if (IS_ERR(priv->base))
67 return PTR_ERR(priv->base);
68
69 econfig.stride = 4;
70 econfig.word_size = 4;
71 econfig.reg_read = mtk_reg_read;
72 econfig.reg_write = mtk_reg_write;
73 econfig.size = resource_size(res);
74 econfig.priv = priv;
75 econfig.dev = dev;
76 nvmem = devm_nvmem_register(dev, &econfig);
77
78 return PTR_ERR_OR_ZERO(nvmem);
79}
80
81static const struct of_device_id mtk_efuse_of_match[] = {
82 { .compatible = "mediatek,mt8173-efuse",},
83 { .compatible = "mediatek,efuse",},
84 {/* sentinel */},
85};
86MODULE_DEVICE_TABLE(of, mtk_efuse_of_match);
87
88static struct platform_driver mtk_efuse_driver = {
89 .probe = mtk_efuse_probe,
90 .driver = {
91 .name = "mediatek,efuse",
92 .of_match_table = mtk_efuse_of_match,
93 },
94};
95
96static int __init mtk_efuse_init(void)
97{
98 int ret;
99
100 ret = platform_driver_register(&mtk_efuse_driver);
101 if (ret) {
102 pr_err("Failed to register efuse driver\n");
103 return ret;
104 }
105
106 return 0;
107}
108
109static void __exit mtk_efuse_exit(void)
110{
111 return platform_driver_unregister(&mtk_efuse_driver);
112}
113
114subsys_initcall(mtk_efuse_init);
115module_exit(mtk_efuse_exit);
116
117MODULE_AUTHOR("Andrew-CT Chen <andrew-ct.chen@mediatek.com>");
118MODULE_DESCRIPTION("Mediatek EFUSE driver");
119MODULE_LICENSE("GPL v2");
120