Staging
v0.5.1
v0.5.1
https://github.com/torvalds/linux
Tip revision: 9561de3a55bed6bdd44a12820ba81ec416e705a7 authored by Linus Torvalds on 04 June 2023, 18:04:27 UTC
Linux 6.4-rc5
Linux 6.4-rc5
Tip revision: 9561de3
mtk-efuse.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2015 MediaTek Inc.
* Author: Andrew-CT Chen <andrew-ct.chen@mediatek.com>
*/
#include <linux/device.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/io.h>
#include <linux/nvmem-provider.h>
#include <linux/platform_device.h>
#include <linux/property.h>
struct mtk_efuse_pdata {
bool uses_post_processing;
};
struct mtk_efuse_priv {
void __iomem *base;
};
static int mtk_reg_read(void *context,
unsigned int reg, void *_val, size_t bytes)
{
struct mtk_efuse_priv *priv = context;
void __iomem *addr = priv->base + reg;
u8 *val = _val;
int i;
for (i = 0; i < bytes; i++, val++)
*val = readb(addr + i);
return 0;
}
static int mtk_efuse_gpu_speedbin_pp(void *context, const char *id, int index,
unsigned int offset, void *data, size_t bytes)
{
u8 *val = data;
if (val[0] < 8)
val[0] = BIT(val[0]);
return 0;
}
static void mtk_efuse_fixup_cell_info(struct nvmem_device *nvmem,
struct nvmem_layout *layout,
struct nvmem_cell_info *cell)
{
size_t sz = strlen(cell->name);
/*
* On some SoCs, the GPU speedbin is not read as bitmask but as
* a number with range [0-7] (max 3 bits): post process to use
* it in OPP tables to describe supported-hw.
*/
if (cell->nbits <= 3 &&
strncmp(cell->name, "gpu-speedbin", min(sz, strlen("gpu-speedbin"))) == 0)
cell->read_post_process = mtk_efuse_gpu_speedbin_pp;
}
static struct nvmem_layout mtk_efuse_layout = {
.fixup_cell_info = mtk_efuse_fixup_cell_info,
};
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 = {};
struct mtk_efuse_priv *priv;
const struct mtk_efuse_pdata *pdata;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
if (IS_ERR(priv->base))
return PTR_ERR(priv->base);
pdata = device_get_match_data(dev);
econfig.stride = 1;
econfig.word_size = 1;
econfig.reg_read = mtk_reg_read;
econfig.size = resource_size(res);
econfig.priv = priv;
econfig.dev = dev;
if (pdata->uses_post_processing)
econfig.layout = &mtk_efuse_layout;
nvmem = devm_nvmem_register(dev, &econfig);
return PTR_ERR_OR_ZERO(nvmem);
}
static const struct mtk_efuse_pdata mtk_mt8186_efuse_pdata = {
.uses_post_processing = true,
};
static const struct mtk_efuse_pdata mtk_efuse_pdata = {
.uses_post_processing = false,
};
static const struct of_device_id mtk_efuse_of_match[] = {
{ .compatible = "mediatek,mt8173-efuse", .data = &mtk_efuse_pdata },
{ .compatible = "mediatek,mt8186-efuse", .data = &mtk_mt8186_efuse_pdata },
{ .compatible = "mediatek,efuse", .data = &mtk_efuse_pdata },
{/* sentinel */},
};
MODULE_DEVICE_TABLE(of, mtk_efuse_of_match);
static struct platform_driver mtk_efuse_driver = {
.probe = mtk_efuse_probe,
.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");