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_reg_write(void *context, 32 unsigned int reg, void *_val, size_t bytes) 33 { 34 struct mtk_efuse_priv *priv = context; 35 u32 *val = _val; 36 int i = 0, words = bytes / 4; 37 38 while (words--) 39 writel(*val++, priv->base + reg + (i++ * 4)); 40 41 return 0; 42 } 43 44 static int mtk_efuse_probe(struct platform_device *pdev) 45 { 46 struct device *dev = &pdev->dev; 47 struct resource *res; 48 struct nvmem_device *nvmem; 49 struct nvmem_config econfig = {}; 50 struct mtk_efuse_priv *priv; 51 52 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 53 if (!priv) 54 return -ENOMEM; 55 56 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 57 priv->base = devm_ioremap_resource(dev, res); 58 if (IS_ERR(priv->base)) 59 return PTR_ERR(priv->base); 60 61 econfig.stride = 4; 62 econfig.word_size = 4; 63 econfig.reg_read = mtk_reg_read; 64 econfig.reg_write = mtk_reg_write; 65 econfig.size = resource_size(res); 66 econfig.priv = priv; 67 econfig.dev = dev; 68 nvmem = devm_nvmem_register(dev, &econfig); 69 70 return PTR_ERR_OR_ZERO(nvmem); 71 } 72 73 static const struct of_device_id mtk_efuse_of_match[] = { 74 { .compatible = "mediatek,mt8173-efuse",}, 75 { .compatible = "mediatek,efuse",}, 76 {/* sentinel */}, 77 }; 78 MODULE_DEVICE_TABLE(of, mtk_efuse_of_match); 79 80 static struct platform_driver mtk_efuse_driver = { 81 .probe = mtk_efuse_probe, 82 .driver = { 83 .name = "mediatek,efuse", 84 .of_match_table = mtk_efuse_of_match, 85 }, 86 }; 87 88 static int __init mtk_efuse_init(void) 89 { 90 int ret; 91 92 ret = platform_driver_register(&mtk_efuse_driver); 93 if (ret) { 94 pr_err("Failed to register efuse driver\n"); 95 return ret; 96 } 97 98 return 0; 99 } 100 101 static void __exit mtk_efuse_exit(void) 102 { 103 return platform_driver_unregister(&mtk_efuse_driver); 104 } 105 106 subsys_initcall(mtk_efuse_init); 107 module_exit(mtk_efuse_exit); 108 109 MODULE_AUTHOR("Andrew-CT Chen <andrew-ct.chen@mediatek.com>"); 110 MODULE_DESCRIPTION("Mediatek EFUSE driver"); 111 MODULE_LICENSE("GPL v2"); 112