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// SPDX-License-Identifier: GPL-2.0
/*
* Intel BayTrail PMIC I2C bus semaphore implementation
* Copyright (c) 2014, Intel Corporation.
*/
#include <linux/device.h>
#include <linux/acpi.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <asm/iosf_mbi.h>
#include "i2c-designware-core.h"
int i2c_dw_baytrail_probe_lock_support(struct dw_i2c_dev *dev)
{
acpi_status status;
unsigned long long shared_host = 0;
acpi_handle handle;
if (!dev)
return -ENODEV;
handle = ACPI_HANDLE(dev->dev);
if (!handle)
return -ENODEV;
status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host);
if (ACPI_FAILURE(status))
return -ENODEV;
if (!shared_host)
return -ENODEV;
if (!iosf_mbi_available())
return -EPROBE_DEFER;
dev_info(dev->dev, "I2C bus managed by PUNIT\n");
dev->acquire_lock = iosf_mbi_block_punit_i2c_access;
dev->release_lock = iosf_mbi_unblock_punit_i2c_access;
dev->shared_with_punit = true;
return 0;
}
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