// SPDX-License-Identifier: GPL-2.0-only /* * Apple SoC eFuse driver * * Copyright (C) The Asahi Linux Contributors */ #include <linux/io.h> #include <linux/mod_devicetable.h> #include <linux/module.h> #include <linux/nvmem-provider.h> #include <linux/platform_device.h> struct apple_efuses_priv { void __iomem *fuses; }; static int apple_efuses_read(void *context, unsigned int offset, void *val, size_t bytes) { struct apple_efuses_priv *priv = context; u32 *dst = val; while (bytes >= sizeof(u32)) { *dst++ = readl_relaxed(priv->fuses + offset); bytes -= sizeof(u32); offset += sizeof(u32); } return 0; } static int apple_efuses_probe(struct platform_device *pdev) { struct apple_efuses_priv *priv; struct resource *res; struct nvmem_config config = { .dev = &pdev->dev, .add_legacy_fixed_of_cells = true, .read_only = true, .reg_read = apple_efuses_read, .stride = sizeof(u32), .word_size = sizeof(u32), .name = "apple_efuses_nvmem", .id = NVMEM_DEVID_AUTO, .root_only = true, }; priv = devm_kzalloc(config.dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; priv->fuses = devm_platform_get_and_ioremap_resource(pdev, 0, &res); if (IS_ERR(priv->fuses)) return PTR_ERR(priv->fuses); config.priv = priv; config.size = resource_size(res); return PTR_ERR_OR_ZERO(devm_nvmem_register(config.dev, &config)); } static const struct of_device_id apple_efuses_of_match[] = { { .compatible = "apple,efuses", }, {} }; MODULE_DEVICE_TABLE(of, apple_efuses_of_match); static struct platform_driver apple_efuses_driver = { .driver = { .name = "apple_efuses", .of_match_table = apple_efuses_of_match, }, .probe = apple_efuses_probe, }; module_platform_driver(apple_efuses_driver); MODULE_AUTHOR("Sven Peter <sven@svenpeter.dev>"); MODULE_DESCRIPTION("Apple SoC eFuse driver"); MODULE_LICENSE("GPL");