drivers/nvmem/mtk-efuse.c

   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");