linux/drivers/nvmem/meson-efuse.c
Jerome Brunet e55077307d nvmem: meson-efuse: add write support
Add write support to the meson-gx efuse driver.
Beware, this efuse is one time programmable !

Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14 16:20:48 +02:00

84 lines
2.2 KiB
C

/*
* Amlogic Meson GX eFuse Driver
*
* Copyright (c) 2016 Endless Computers, Inc.
* Author: Carlo Caione <carlo@endlessm.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License 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/module.h>
#include <linux/nvmem-provider.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/firmware/meson/meson_sm.h>
static int meson_efuse_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
return meson_sm_call_read((u8 *)val, bytes, SM_EFUSE_READ, offset,
bytes, 0, 0, 0);
}
static int meson_efuse_write(void *context, unsigned int offset,
void *val, size_t bytes)
{
return meson_sm_call_write((u8 *)val, bytes, SM_EFUSE_WRITE, offset,
bytes, 0, 0, 0);
}
static const struct of_device_id meson_efuse_match[] = {
{ .compatible = "amlogic,meson-gxbb-efuse", },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, meson_efuse_match);
static int meson_efuse_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct nvmem_device *nvmem;
struct nvmem_config *econfig;
unsigned int size;
if (meson_sm_call(SM_EFUSE_USER_MAX, &size, 0, 0, 0, 0, 0) < 0)
return -EINVAL;
econfig = devm_kzalloc(dev, sizeof(*econfig), GFP_KERNEL);
if (!econfig)
return -ENOMEM;
econfig->dev = dev;
econfig->name = dev_name(dev);
econfig->stride = 1;
econfig->word_size = 1;
econfig->reg_read = meson_efuse_read;
econfig->reg_write = meson_efuse_write;
econfig->size = size;
nvmem = devm_nvmem_register(&pdev->dev, econfig);
return PTR_ERR_OR_ZERO(nvmem);
}
static struct platform_driver meson_efuse_driver = {
.probe = meson_efuse_probe,
.driver = {
.name = "meson-efuse",
.of_match_table = meson_efuse_match,
},
};
module_platform_driver(meson_efuse_driver);
MODULE_AUTHOR("Carlo Caione <carlo@endlessm.com>");
MODULE_DESCRIPTION("Amlogic Meson GX NVMEM driver");
MODULE_LICENSE("GPL v2");