1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * UniPhier eFuse driver
4 *
5 * Copyright (C) 2017 Socionext Inc.
6 */
7
8 #include <linux/device.h>
9 #include <linux/io.h>
10 #include <linux/module.h>
11 #include <linux/nvmem-provider.h>
12 #include <linux/platform_device.h>
13
14 struct uniphier_efuse_priv {
15 void __iomem *base;
16 };
17
uniphier_reg_read(void * context,unsigned int reg,void * _val,size_t bytes)18 static int uniphier_reg_read(void *context,
19 unsigned int reg, void *_val, size_t bytes)
20 {
21 struct uniphier_efuse_priv *priv = context;
22 u8 *val = _val;
23 int offs;
24
25 for (offs = 0; offs < bytes; offs += sizeof(u8))
26 *val++ = readb(priv->base + reg + offs);
27
28 return 0;
29 }
30
uniphier_efuse_probe(struct platform_device * pdev)31 static int uniphier_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 uniphier_efuse_priv *priv;
38
39 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
40 if (!priv)
41 return -ENOMEM;
42
43 priv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
44 if (IS_ERR(priv->base))
45 return PTR_ERR(priv->base);
46
47 econfig.stride = 1;
48 econfig.word_size = 1;
49 econfig.read_only = true;
50 econfig.reg_read = uniphier_reg_read;
51 econfig.size = resource_size(res);
52 econfig.priv = priv;
53 econfig.dev = dev;
54 econfig.add_legacy_fixed_of_cells = true;
55 nvmem = devm_nvmem_register(dev, &econfig);
56
57 return PTR_ERR_OR_ZERO(nvmem);
58 }
59
60 static const struct of_device_id uniphier_efuse_of_match[] = {
61 { .compatible = "socionext,uniphier-efuse",},
62 {/* sentinel */},
63 };
64 MODULE_DEVICE_TABLE(of, uniphier_efuse_of_match);
65
66 static struct platform_driver uniphier_efuse_driver = {
67 .probe = uniphier_efuse_probe,
68 .driver = {
69 .name = "uniphier-efuse",
70 .of_match_table = uniphier_efuse_of_match,
71 },
72 };
73 module_platform_driver(uniphier_efuse_driver);
74
75 MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
76 MODULE_DESCRIPTION("UniPhier eFuse driver");
77 MODULE_LICENSE("GPL v2");
78