linux-imx

/*

 * drivers/mfd/mfd-core.c

 *

 * core MFD support

 * Copyright (c) 2006 Ian Molton

 * Copyright (c) 2007,2008 Dmitry Baryshkov

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 */

​

#include <linux/kernel.h>

#include <linux/platform_device.h>

#include <linux/acpi.h>

#include <linux/property.h>

#include <linux/mfd/core.h>

#include <linux/pm_runtime.h>

#include <linux/slab.h>

#include <linux/module.h>

#include <linux/irqdomain.h>

#include <linux/of.h>

#include <linux/regulator/consumer.h>

​

static struct device_type mfd_dev_type = {

    .name   = "mfd_device",

};

​

int mfd_cell_enable(struct platform_device *pdev)

{

    const struct mfd_cell *cell = mfd_get_cell(pdev);

    int err = 0;

​

    /* only call enable hook if the cell wasn't previously enabled */

    if (atomic_inc_return(cell->usage_count) == 1)

        err = cell->enable(pdev);

​

    /* if the enable hook failed, decrement counter to allow retries */

    if (err)

        atomic_dec(cell->usage_count);

​

    return err;

}

EXPORT_SYMBOL(mfd_cell_enable);

​

int mfd_cell_disable(struct platform_device *pdev)

{

    const struct mfd_cell *cell = mfd_get_cell(pdev);

    int err = 0;

​

    /* only disable if no other clients are using it */

    if (atomic_dec_return(cell->usage_count) == 0)

        err = cell->disable(pdev);

​

    /* if the disable hook failed, increment to allow retries */

    if (err)

        atomic_inc(cell->usage_count);

​

    /* sanity check; did someone call disable too many times? */

    WARN_ON(atomic_read(cell->usage_count) < 0);

​

    return err;