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
mtk_reg_read(void * context,unsigned int reg,void * _val,size_t bytes)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 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
mtk_efuse_probe(struct platform_device * pdev)31 static 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
59 static const struct of_device_id mtk_efuse_of_match[] = {
60 { .compatible = "mediatek,mt8173-efuse",},
61 { .compatible = "mediatek,efuse",},
62 {/* sentinel */},
63 };
64 MODULE_DEVICE_TABLE(of, mtk_efuse_of_match);
65
66 static 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
mtk_efuse_init(void)74 static 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
mtk_efuse_exit(void)87 static void __exit mtk_efuse_exit(void)
88 {
89 return platform_driver_unregister(&mtk_efuse_driver);
90 }
91
92 subsys_initcall(mtk_efuse_init);
93 module_exit(mtk_efuse_exit);
94
95 MODULE_AUTHOR("Andrew-CT Chen <andrew-ct.chen@mediatek.com>");
96 MODULE_DESCRIPTION("Mediatek EFUSE driver");
97 MODULE_LICENSE("GPL v2");
98