linux-imx

/*

 *  Copyright (C) 2014 Linaro Ltd

 *

 * Author: Ulf Hansson <ulf.hansson@linaro.org>

 *

 * License terms: GNU General Public License (GPL) version 2

 *

 *  MMC power sequence management

 */

#include <linux/kernel.h>

#include <linux/err.h>

#include <linux/module.h>

#include <linux/of.h>

​

#include <linux/mmc/host.h>

​

#include "pwrseq.h"

​

static DEFINE_MUTEX(pwrseq_list_mutex);

static LIST_HEAD(pwrseq_list);

​

int mmc_pwrseq_alloc(struct mmc_host *host)

{

    struct device_node *np;

    struct mmc_pwrseq *p;

​

    np = of_parse_phandle(host->parent->of_node, "mmc-pwrseq", 0);

    if (!np)

        return 0;

​

    mutex_lock(&pwrseq_list_mutex);

    list_for_each_entry(p, &pwrseq_list, pwrseq_node) {

        if (p->dev->of_node == np) {

            if (!try_module_get(p->owner))

                dev_err(host->parent,

                    "increasing module refcount failed\n");

            else

                host->pwrseq = p;

​

            break;

        }

    }

​

    of_node_put(np);

    mutex_unlock(&pwrseq_list_mutex);

​

    if (!host->pwrseq)

        return -EPROBE_DEFER;

​

    dev_info(host->parent, "allocated mmc-pwrseq\n");

​

    return 0;

}

​

void mmc_pwrseq_pre_power_on(struct mmc_host *host)

{

    struct mmc_pwrseq *pwrseq = host->pwrseq;

​

    if (pwrseq && pwrseq->ops->pre_power_on)

        pwrseq->ops->pre_power_on(host);

}

​

void mmc_pwrseq_post_power_on(struct mmc_host *host)