xref: /linux/drivers/nvmem/mtk-efuse.c (revision 0883c2c06fb5bcf5b9e008270827e63c09a88c1e)
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/nvmem-provider.h>
18 #include <linux/platform_device.h>
19 #include <linux/regmap.h>
20 
21 static struct regmap_config mtk_regmap_config = {
22 	.reg_bits = 32,
23 	.val_bits = 32,
24 	.reg_stride = 4,
25 };
26 
27 static int mtk_efuse_probe(struct platform_device *pdev)
28 {
29 	struct device *dev = &pdev->dev;
30 	struct resource *res;
31 	struct nvmem_device *nvmem;
32 	struct nvmem_config *econfig;
33 	struct regmap *regmap;
34 	void __iomem *base;
35 
36 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
37 	base = devm_ioremap_resource(dev, res);
38 	if (IS_ERR(base))
39 		return PTR_ERR(base);
40 
41 	econfig = devm_kzalloc(dev, sizeof(*econfig), GFP_KERNEL);
42 	if (!econfig)
43 		return -ENOMEM;
44 
45 	mtk_regmap_config.max_register = resource_size(res) - 1;
46 
47 	regmap = devm_regmap_init_mmio(dev, base, &mtk_regmap_config);
48 	if (IS_ERR(regmap)) {
49 		dev_err(dev, "regmap init failed\n");
50 		return PTR_ERR(regmap);
51 	}
52 
53 	econfig->dev = dev;
54 	econfig->owner = THIS_MODULE;
55 	nvmem = nvmem_register(econfig);
56 	if (IS_ERR(nvmem))
57 		return PTR_ERR(nvmem);
58 
59 	platform_set_drvdata(pdev, nvmem);
60 
61 	return 0;
62 }
63 
64 static int mtk_efuse_remove(struct platform_device *pdev)
65 {
66 	struct nvmem_device *nvmem = platform_get_drvdata(pdev);
67 
68 	return nvmem_unregister(nvmem);
69 }
70 
71 static const struct of_device_id mtk_efuse_of_match[] = {
72 	{ .compatible = "mediatek,mt8173-efuse",},
73 	{ .compatible = "mediatek,efuse",},
74 	{/* sentinel */},
75 };
76 MODULE_DEVICE_TABLE(of, mtk_efuse_of_match);
77 
78 static struct platform_driver mtk_efuse_driver = {
79 	.probe = mtk_efuse_probe,
80 	.remove = mtk_efuse_remove,
81 	.driver = {
82 		.name = "mediatek,efuse",
83 		.of_match_table = mtk_efuse_of_match,
84 	},
85 };
86 
87 static int __init mtk_efuse_init(void)
88 {
89 	int ret;
90 
91 	ret = platform_driver_register(&mtk_efuse_driver);
92 	if (ret) {
93 		pr_err("Failed to register efuse driver\n");
94 		return ret;
95 	}
96 
97 	return 0;
98 }
99 
100 static void __exit mtk_efuse_exit(void)
101 {
102 	return platform_driver_unregister(&mtk_efuse_driver);
103 }
104 
105 subsys_initcall(mtk_efuse_init);
106 module_exit(mtk_efuse_exit);
107 
108 MODULE_AUTHOR("Andrew-CT Chen <andrew-ct.chen@mediatek.com>");
109 MODULE_DESCRIPTION("Mediatek EFUSE driver");
110 MODULE_LICENSE("GPL v2");
111