linux/drivers/mmc/core/pwrseq_sd8787.c

118 lines
3.2 KiB
C

/*
* pwrseq_sd8787.c - power sequence support for Marvell SD8787 BT + Wifi chip
*
* Copyright (C) 2016 Matt Ranostay <matt@ranostay.consulting>
*
* Based on the original work pwrseq_simple.c
* Copyright (C) 2014 Linaro Ltd
* Author: Ulf Hansson <ulf.hansson@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/gpio/consumer.h>
#include <linux/mmc/host.h>
#include "pwrseq.h"
struct mmc_pwrseq_sd8787 {
struct mmc_pwrseq pwrseq;
struct gpio_desc *reset_gpio;
struct gpio_desc *pwrdn_gpio;
};
#define to_pwrseq_sd8787(p) container_of(p, struct mmc_pwrseq_sd8787, pwrseq)
static void mmc_pwrseq_sd8787_pre_power_on(struct mmc_host *host)
{
struct mmc_pwrseq_sd8787 *pwrseq = to_pwrseq_sd8787(host->pwrseq);
gpiod_set_value_cansleep(pwrseq->reset_gpio, 1);
msleep(300);
gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 1);
}
static void mmc_pwrseq_sd8787_power_off(struct mmc_host *host)
{
struct mmc_pwrseq_sd8787 *pwrseq = to_pwrseq_sd8787(host->pwrseq);
gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 0);
gpiod_set_value_cansleep(pwrseq->reset_gpio, 0);
}
static const struct mmc_pwrseq_ops mmc_pwrseq_sd8787_ops = {
.pre_power_on = mmc_pwrseq_sd8787_pre_power_on,
.power_off = mmc_pwrseq_sd8787_power_off,
};
static const struct of_device_id mmc_pwrseq_sd8787_of_match[] = {
{ .compatible = "mmc-pwrseq-sd8787",},
{/* sentinel */},
};
MODULE_DEVICE_TABLE(of, mmc_pwrseq_sd8787_of_match);
static int mmc_pwrseq_sd8787_probe(struct platform_device *pdev)
{
struct mmc_pwrseq_sd8787 *pwrseq;
struct device *dev = &pdev->dev;
pwrseq = devm_kzalloc(dev, sizeof(*pwrseq), GFP_KERNEL);
if (!pwrseq)
return -ENOMEM;
pwrseq->pwrdn_gpio = devm_gpiod_get(dev, "powerdown", GPIOD_OUT_LOW);
if (IS_ERR(pwrseq->pwrdn_gpio))
return PTR_ERR(pwrseq->pwrdn_gpio);
pwrseq->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
if (IS_ERR(pwrseq->reset_gpio))
return PTR_ERR(pwrseq->reset_gpio);
pwrseq->pwrseq.dev = dev;
pwrseq->pwrseq.ops = &mmc_pwrseq_sd8787_ops;
pwrseq->pwrseq.owner = THIS_MODULE;
platform_set_drvdata(pdev, pwrseq);
return mmc_pwrseq_register(&pwrseq->pwrseq);
}
static int mmc_pwrseq_sd8787_remove(struct platform_device *pdev)
{
struct mmc_pwrseq_sd8787 *pwrseq = platform_get_drvdata(pdev);
mmc_pwrseq_unregister(&pwrseq->pwrseq);
return 0;
}
static struct platform_driver mmc_pwrseq_sd8787_driver = {
.probe = mmc_pwrseq_sd8787_probe,
.remove = mmc_pwrseq_sd8787_remove,
.driver = {
.name = "pwrseq_sd8787",
.of_match_table = mmc_pwrseq_sd8787_of_match,
},
};
module_platform_driver(mmc_pwrseq_sd8787_driver);
MODULE_LICENSE("GPL v2");