linux/drivers/nvmem/uniphier-efuse.c

98 lines
2.5 KiB
C

/*
* UniPhier eFuse driver
*
* Copyright (C) 2017 Socionext Inc.
*
* 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/io.h>
#include <linux/module.h>
#include <linux/nvmem-provider.h>
#include <linux/platform_device.h>
struct uniphier_efuse_priv {
void __iomem *base;
};
static int uniphier_reg_read(void *context,
unsigned int reg, void *_val, size_t bytes)
{
struct uniphier_efuse_priv *priv = context;
u8 *val = _val;
int offs;
for (offs = 0; offs < bytes; offs += sizeof(u8))
*val++ = readb(priv->base + reg + offs);
return 0;
}
static int uniphier_efuse_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct resource *res;
struct nvmem_device *nvmem;
struct nvmem_config econfig = {};
struct uniphier_efuse_priv *priv;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
priv->base = devm_ioremap_resource(dev, res);
if (IS_ERR(priv->base))
return PTR_ERR(priv->base);
econfig.stride = 1;
econfig.word_size = 1;
econfig.read_only = true;
econfig.reg_read = uniphier_reg_read;
econfig.size = resource_size(res);
econfig.priv = priv;
econfig.dev = dev;
nvmem = nvmem_register(&econfig);
if (IS_ERR(nvmem))
return PTR_ERR(nvmem);
platform_set_drvdata(pdev, nvmem);
return 0;
}
static int uniphier_efuse_remove(struct platform_device *pdev)
{
struct nvmem_device *nvmem = platform_get_drvdata(pdev);
return nvmem_unregister(nvmem);
}
static const struct of_device_id uniphier_efuse_of_match[] = {
{ .compatible = "socionext,uniphier-efuse",},
{/* sentinel */},
};
MODULE_DEVICE_TABLE(of, uniphier_efuse_of_match);
static struct platform_driver uniphier_efuse_driver = {
.probe = uniphier_efuse_probe,
.remove = uniphier_efuse_remove,
.driver = {
.name = "uniphier-efuse",
.of_match_table = uniphier_efuse_of_match,
},
};
module_platform_driver(uniphier_efuse_driver);
MODULE_AUTHOR("Keiji Hayashibara <hayashibara.keiji@socionext.com>");
MODULE_DESCRIPTION("UniPhier eFuse driver");
MODULE_LICENSE("GPL v2");