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/mod_devicetable.h> 12 #include <linux/nvmem-provider.h> 13 #include <linux/platform_device.h> 14 15 struct uniphier_efuse_priv { 16 void __iomem *base; 17 }; 18 19 static int uniphier_reg_read(void *context, 20 unsigned int reg, void *_val, size_t bytes) 21 { 22 struct uniphier_efuse_priv *priv = context; 23 u8 *val = _val; 24 int offs; 25 26 for (offs = 0; offs < bytes; offs += sizeof(u8)) 27 *val++ = readb(priv->base + reg + offs); 28 29 return 0; 30 } 31 32 static int uniphier_efuse_probe(struct platform_device *pdev) 33 { 34 struct device *dev = &pdev->dev; 35 struct resource *res; 36 struct nvmem_device *nvmem; 37 struct nvmem_config econfig = {}; 38 struct uniphier_efuse_priv *priv; 39 40 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 41 if (!priv) 42 return -ENOMEM; 43 44 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 45 priv->base = devm_ioremap_resource(dev, res); 46 if (IS_ERR(priv->base)) 47 return PTR_ERR(priv->base); 48 49 econfig.stride = 1; 50 econfig.word_size = 1; 51 econfig.read_only = true; 52 econfig.reg_read = uniphier_reg_read; 53 econfig.size = resource_size(res); 54 econfig.priv = priv; 55 econfig.dev = dev; 56 nvmem = devm_nvmem_register(dev, &econfig); 57 58 return PTR_ERR_OR_ZERO(nvmem); 59 } 60 61 static const struct of_device_id uniphier_efuse_of_match[] = { 62 { .compatible = "socionext,uniphier-efuse",}, 63 {/* sentinel */}, 64 }; 65 MODULE_DEVICE_TABLE(of, uniphier_efuse_of_match); 66 67 static struct platform_driver uniphier_efuse_driver = { 68 .probe = uniphier_efuse_probe, 69 .driver = { 70 .name = "uniphier-efuse", 71 .of_match_table = uniphier_efuse_of_match, 72 }, 73 }; 74 module_platform_driver(uniphier_efuse_driver); 75 76 MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>"); 77 MODULE_DESCRIPTION("UniPhier eFuse driver"); 78 MODULE_LICENSE("GPL v2"); 79