linux/drivers/nvmem/mtk-efuse.c

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/*
* Copyright (c) 2015 MediaTek Inc.
* Author: Andrew-CT Chen <andrew-ct.chen@mediatek.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/device.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/nvmem-provider.h>
#include <linux/platform_device.h>
static int mtk_reg_read(void *context,
unsigned int reg, void *_val, size_t bytes)
{
void __iomem *base = context;
u32 *val = _val;
int i = 0, words = bytes / 4;
while (words--)
*val++ = readl(base + reg + (i++ * 4));
return 0;
}
static int mtk_reg_write(void *context,
unsigned int reg, void *_val, size_t bytes)
{
void __iomem *base = context;
u32 *val = _val;
int i = 0, words = bytes / 4;
while (words--)
writel(*val++, base + reg + (i++ * 4));
return 0;
}
static int mtk_efuse_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct resource *res;
struct nvmem_device *nvmem;
struct nvmem_config *econfig;
void __iomem *base;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base = devm_ioremap_resource(dev, res);
if (IS_ERR(base))
return PTR_ERR(base);
econfig = devm_kzalloc(dev, sizeof(*econfig), GFP_KERNEL);
if (!econfig)
return -ENOMEM;
econfig->stride = 4;
econfig->word_size = 4;
econfig->reg_read = mtk_reg_read;
econfig->reg_write = mtk_reg_write;
econfig->size = resource_size(res);
econfig->priv = base;
econfig->dev = dev;
econfig->owner = THIS_MODULE;
nvmem = nvmem_register(econfig);
if (IS_ERR(nvmem))
return PTR_ERR(nvmem);
platform_set_drvdata(pdev, nvmem);
return 0;
}
static int mtk_efuse_remove(struct platform_device *pdev)
{
struct nvmem_device *nvmem = platform_get_drvdata(pdev);
return nvmem_unregister(nvmem);
}
static const struct of_device_id mtk_efuse_of_match[] = {
{ .compatible = "mediatek,mt8173-efuse",},
{ .compatible = "mediatek,efuse",},
{/* sentinel */},
};
MODULE_DEVICE_TABLE(of, mtk_efuse_of_match);
static struct platform_driver mtk_efuse_driver = {
.probe = mtk_efuse_probe,
.remove = mtk_efuse_remove,
.driver = {
.name = "mediatek,efuse",
.of_match_table = mtk_efuse_of_match,
},
};
static int __init mtk_efuse_init(void)
{
int ret;
ret = platform_driver_register(&mtk_efuse_driver);
if (ret) {
pr_err("Failed to register efuse driver\n");
return ret;
}
return 0;
}
static void __exit mtk_efuse_exit(void)
{
return platform_driver_unregister(&mtk_efuse_driver);
}
subsys_initcall(mtk_efuse_init);
module_exit(mtk_efuse_exit);
MODULE_AUTHOR("Andrew-CT Chen <andrew-ct.chen@mediatek.com>");
MODULE_DESCRIPTION("Mediatek EFUSE driver");
MODULE_LICENSE("GPL v2");