linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * Copyright (c) 2013, The Linux Foundation. All rights reserved.

 * Copyright (c) 2015, Sony Mobile Communications AB

 */

​

#include <linux/hwspinlock.h>

#include <linux/io.h>

#include <linux/kernel.h>

#include <linux/mfd/syscon.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/of_device.h>

#include <linux/platform_device.h>

#include <linux/pm_runtime.h>

#include <linux/regmap.h>

​

#include "hwspinlock_internal.h"

​

#define QCOM_MUTEX_APPS_PROC_ID 1

#define QCOM_MUTEX_NUM_LOCKS    32

​

static int qcom_hwspinlock_trylock(struct hwspinlock *lock)

{

    struct regmap_field *field = lock->priv;

    u32 lock_owner;

    int ret;

​

    ret = regmap_field_write(field, QCOM_MUTEX_APPS_PROC_ID);

    if (ret)

        return ret;

​

    ret = regmap_field_read(field, &lock_owner);

    if (ret)

        return ret;

​

    return lock_owner == QCOM_MUTEX_APPS_PROC_ID;

}

​

static void qcom_hwspinlock_unlock(struct hwspinlock *lock)

{

    struct regmap_field *field = lock->priv;

    u32 lock_owner;

    int ret;

​

    ret = regmap_field_read(field, &lock_owner);

    if (ret) {

        pr_err("%s: unable to query spinlock owner\n", __func__);

        return;

    }

​

    if (lock_owner != QCOM_MUTEX_APPS_PROC_ID) {

        pr_err("%s: spinlock not owned by us (actual owner is %d)\n",

                __func__, lock_owner);

    }

​

    ret = regmap_field_write(field, 0);

    if (ret)

        pr_err("%s: failed to unlock spinlock\n", __func__);

}

​

static const struct hwspinlock_ops qcom_hwspinlock_ops = {

    .trylock    = qcom_hwspinlock_trylock,