mirror of https://gitee.com/openkylin/linux.git
119 lines
2.3 KiB
C
119 lines
2.3 KiB
C
/*
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* Copyright (C) 2014 Linaro Ltd
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*
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* Author: Ulf Hansson <ulf.hansson@linaro.org>
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*
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* License terms: GNU General Public License (GPL) version 2
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*
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* MMC power sequence management
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*/
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#include <linux/kernel.h>
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#include <linux/err.h>
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#include <linux/module.h>
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#include <linux/of.h>
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#include <linux/mmc/host.h>
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#include "pwrseq.h"
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static DEFINE_MUTEX(pwrseq_list_mutex);
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static LIST_HEAD(pwrseq_list);
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int mmc_pwrseq_alloc(struct mmc_host *host)
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{
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struct device_node *np;
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struct mmc_pwrseq *p;
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np = of_parse_phandle(host->parent->of_node, "mmc-pwrseq", 0);
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if (!np)
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return 0;
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mutex_lock(&pwrseq_list_mutex);
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list_for_each_entry(p, &pwrseq_list, pwrseq_node) {
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if (p->dev->of_node == np) {
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if (!try_module_get(p->owner))
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dev_err(host->parent,
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"increasing module refcount failed\n");
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else
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host->pwrseq = p;
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break;
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}
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}
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of_node_put(np);
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mutex_unlock(&pwrseq_list_mutex);
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if (!host->pwrseq)
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return -EPROBE_DEFER;
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dev_info(host->parent, "allocated mmc-pwrseq\n");
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return 0;
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}
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void mmc_pwrseq_pre_power_on(struct mmc_host *host)
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{
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struct mmc_pwrseq *pwrseq = host->pwrseq;
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if (pwrseq && pwrseq->ops->pre_power_on)
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pwrseq->ops->pre_power_on(host);
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}
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void mmc_pwrseq_post_power_on(struct mmc_host *host)
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{
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struct mmc_pwrseq *pwrseq = host->pwrseq;
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if (pwrseq && pwrseq->ops->post_power_on)
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pwrseq->ops->post_power_on(host);
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}
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void mmc_pwrseq_power_off(struct mmc_host *host)
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{
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struct mmc_pwrseq *pwrseq = host->pwrseq;
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if (pwrseq && pwrseq->ops->power_off)
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pwrseq->ops->power_off(host);
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}
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void mmc_pwrseq_reset(struct mmc_host *host)
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{
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struct mmc_pwrseq *pwrseq = host->pwrseq;
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if (pwrseq && pwrseq->ops->reset)
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pwrseq->ops->reset(host);
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}
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void mmc_pwrseq_free(struct mmc_host *host)
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{
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struct mmc_pwrseq *pwrseq = host->pwrseq;
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if (pwrseq) {
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module_put(pwrseq->owner);
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host->pwrseq = NULL;
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}
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}
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int mmc_pwrseq_register(struct mmc_pwrseq *pwrseq)
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{
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if (!pwrseq || !pwrseq->ops || !pwrseq->dev)
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return -EINVAL;
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mutex_lock(&pwrseq_list_mutex);
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list_add(&pwrseq->pwrseq_node, &pwrseq_list);
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mutex_unlock(&pwrseq_list_mutex);
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return 0;
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}
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EXPORT_SYMBOL_GPL(mmc_pwrseq_register);
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void mmc_pwrseq_unregister(struct mmc_pwrseq *pwrseq)
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{
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if (pwrseq) {
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mutex_lock(&pwrseq_list_mutex);
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list_del(&pwrseq->pwrseq_node);
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mutex_unlock(&pwrseq_list_mutex);
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}
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}
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EXPORT_SYMBOL_GPL(mmc_pwrseq_unregister);
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