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 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 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 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 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