kernel_samsung_a34x-permissive/drivers/misc/mediatek/eccci/ccci_rtc.c

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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2019 MediaTek Inc.
*/
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/nvmem-consumer.h>
#include <linux/types.h>
#include <linux/err.h>
#include "ccci_rtc.h"
#include "ccci_core.h"
#include "ccci_debug.h"
#define TAG "ccci_rtc"
static int g_ccci_rtc_val;
int mtk_crystal_exist_status(void)
{
CCCI_ERROR_LOG(-1, TAG, "[%s] g_ccci_rtc_val : %d.",
__func__, g_ccci_rtc_val);
return g_ccci_rtc_val;
}
EXPORT_SYMBOL(mtk_crystal_exist_status);
static int ccci_get_rtc_info(struct platform_device *pdev)
{
struct nvmem_cell *cell = NULL;
u8 *buf = NULL;
ssize_t len = 0;
cell = nvmem_cell_get(&pdev->dev, "external-32k");
if (!cell) {
CCCI_ERROR_LOG(-1, TAG, "[%s] nvmem_cell_get fail: %zu",
__func__, PTR_ERR(cell));
return -1;
}
if (IS_ERR(cell)) {
CCCI_ERROR_LOG(-1, TAG, "[%s] nvmem_cell_get fail: %zu",
__func__, PTR_ERR(cell));
if (PTR_ERR(cell) == -EPROBE_DEFER)
return PTR_ERR(cell);
goto fail;
}
buf = (u8 *)nvmem_cell_read(cell, &len);
nvmem_cell_put(cell);
if (IS_ERR(buf)) {
CCCI_ERROR_LOG(-1, TAG, "[%s] nvmem_cell_read fail: %zu\n",
__func__, PTR_ERR(buf));
goto fail;
}
g_ccci_rtc_val = (u8)(*buf);
kfree(buf);
CCCI_NORMAL_LOG(-1, TAG, "[%s] g_ccci_rtc_val = %d; len = %zu\n",
__func__, g_ccci_rtc_val, len);
return 0;
fail:
return -1;
}
static int ccci_rtc_probe(struct platform_device *pdev)
{
return ccci_get_rtc_info(pdev);
}
static const struct of_device_id ccci_rtc_of_ids[] = {
{.compatible = "mediatek,md_ccci_rtc"},
{}
};
static struct platform_driver ccci_rtc_driver = {
.driver = {
.name = "md_ccci_rtc",
.of_match_table = ccci_rtc_of_ids,
},
.probe = ccci_rtc_probe,
};
static int __init ccci_rtc_init(void)
{
int ret;
ret = platform_driver_register(&ccci_rtc_driver);
if (ret) {
CCCI_ERROR_LOG(-1, TAG, "ccci rtc driver init fail %d", ret);
return ret;
}
return 0;
}
module_init(ccci_rtc_init);
MODULE_AUTHOR("ccci");
MODULE_DESCRIPTION("ccci rtc driver");
MODULE_LICENSE("GPL");