GNU Linux-libre 5.19-rc6-gnu
[releases.git] / drivers / nvmem / mtk-efuse.c
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
14 struct mtk_efuse_priv {
15         void __iomem *base;
16 };
17
18 static int mtk_reg_read(void *context,
19                         unsigned int reg, void *_val, size_t bytes)
20 {
21         struct mtk_efuse_priv *priv = context;
22         void __iomem *addr = priv->base + reg;
23         u8 *val = _val;
24         int i;
25
26         for (i = 0; i < bytes; i++, val++)
27                 *val = readb(addr + i);
28
29         return 0;
30 }
31
32 static int mtk_efuse_probe(struct platform_device *pdev)
33 {
34         struct device *dev = &pdev->dev;
35         struct resource *res;
36         struct nvmem_device *nvmem;
37         struct nvmem_config econfig = {};
38         struct mtk_efuse_priv *priv;
39
40         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
41         if (!priv)
42                 return -ENOMEM;
43
44         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
45         priv->base = devm_ioremap_resource(dev, res);
46         if (IS_ERR(priv->base))
47                 return PTR_ERR(priv->base);
48
49         econfig.stride = 1;
50         econfig.word_size = 1;
51         econfig.reg_read = mtk_reg_read;
52         econfig.size = resource_size(res);
53         econfig.priv = priv;
54         econfig.dev = dev;
55         nvmem = devm_nvmem_register(dev, &econfig);
56
57         return PTR_ERR_OR_ZERO(nvmem);
58 }
59
60 static const struct of_device_id mtk_efuse_of_match[] = {
61         { .compatible = "mediatek,mt8173-efuse",},
62         { .compatible = "mediatek,efuse",},
63         {/* sentinel */},
64 };
65 MODULE_DEVICE_TABLE(of, mtk_efuse_of_match);
66
67 static struct platform_driver mtk_efuse_driver = {
68         .probe = mtk_efuse_probe,
69         .driver = {
70                 .name = "mediatek,efuse",
71                 .of_match_table = mtk_efuse_of_match,
72         },
73 };
74
75 static int __init mtk_efuse_init(void)
76 {
77         int ret;
78
79         ret = platform_driver_register(&mtk_efuse_driver);
80         if (ret) {
81                 pr_err("Failed to register efuse driver\n");
82                 return ret;
83         }
84
85         return 0;
86 }
87
88 static void __exit mtk_efuse_exit(void)
89 {
90         return platform_driver_unregister(&mtk_efuse_driver);
91 }
92
93 subsys_initcall(mtk_efuse_init);
94 module_exit(mtk_efuse_exit);
95
96 MODULE_AUTHOR("Andrew-CT Chen <andrew-ct.chen@mediatek.com>");
97 MODULE_DESCRIPTION("Mediatek EFUSE driver");
98 MODULE_LICENSE("GPL v2");