tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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/io.h>
18#include <linux/nvmem-provider.h>
19#include <linux/platform_device.h>
20
21static int mtk_reg_read(void *context,
22 unsigned int reg, void *_val, size_t bytes)
23{
24 void __iomem *base = context;
25 u32 *val = _val;
26 int i = 0, words = bytes / 4;
27
28 while (words--)
29 *val++ = readl(base + reg + (i++ * 4));
30
31 return 0;
32}
33
34static int mtk_reg_write(void *context,
35 unsigned int reg, void *_val, size_t bytes)
36{
37 void __iomem *base = context;
38 u32 *val = _val;
39 int i = 0, words = bytes / 4;
40
41 while (words--)
42 writel(*val++, base + reg + (i++ * 4));
43
44 return 0;
45}
46
47static int mtk_efuse_probe(struct platform_device *pdev)
48{
49 struct device *dev = &pdev->dev;
50 struct resource *res;
51 struct nvmem_device *nvmem;
52 struct nvmem_config *econfig;
53 void __iomem *base;
54
55 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
56 base = devm_ioremap_resource(dev, res);
57 if (IS_ERR(base))
58 return PTR_ERR(base);
59
60 econfig = devm_kzalloc(dev, sizeof(*econfig), GFP_KERNEL);
61 if (!econfig)
62 return -ENOMEM;
63
64 econfig->stride = 4;
65 econfig->word_size = 4;
66 econfig->reg_read = mtk_reg_read;
67 econfig->reg_write = mtk_reg_write;
68 econfig->size = resource_size(res);
69 econfig->priv = base;
70 econfig->dev = dev;
71 econfig->owner = THIS_MODULE;
72 nvmem = nvmem_register(econfig);
73 if (IS_ERR(nvmem))
74 return PTR_ERR(nvmem);
75
76 platform_set_drvdata(pdev, nvmem);
77
78 return 0;
79}
80
81static int mtk_efuse_remove(struct platform_device *pdev)
82{
83 struct nvmem_device *nvmem = platform_get_drvdata(pdev);
84
85 return nvmem_unregister(nvmem);
86}
87
88static const struct of_device_id mtk_efuse_of_match[] = {
89 { .compatible = "mediatek,mt8173-efuse",},
90 { .compatible = "mediatek,efuse",},
91 {/* sentinel */},
92};
93MODULE_DEVICE_TABLE(of, mtk_efuse_of_match);
94
95static struct platform_driver mtk_efuse_driver = {
96 .probe = mtk_efuse_probe,
97 .remove = mtk_efuse_remove,
98 .driver = {
99 .name = "mediatek,efuse",
100 .of_match_table = mtk_efuse_of_match,
101 },
102};
103
104static int __init mtk_efuse_init(void)
105{
106 int ret;
107
108 ret = platform_driver_register(&mtk_efuse_driver);
109 if (ret) {
110 pr_err("Failed to register efuse driver\n");
111 return ret;
112 }
113
114 return 0;
115}
116
117static void __exit mtk_efuse_exit(void)
118{
119 return platform_driver_unregister(&mtk_efuse_driver);
120}
121
122subsys_initcall(mtk_efuse_init);
123module_exit(mtk_efuse_exit);
124
125MODULE_AUTHOR("Andrew-CT Chen <andrew-ct.chen@mediatek.com>");
126MODULE_DESCRIPTION("Mediatek EFUSE driver");
127MODULE_LICENSE("GPL v2");