mmc/core/pwrseq_sd8787.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  * pwrseq_sd8787.c - power sequence support for Marvell SD8787 BT + Wifi chip
0004  *
0005  * Copyright (C) 2016 Matt Ranostay <matt@ranostay.consulting>
0006  *
0007  * Based on the original work pwrseq_simple.c
0008  *  Copyright (C) 2014 Linaro Ltd
0009  *  Author: Ulf Hansson <ulf.hansson@linaro.org>
0010  */
0011
0012 #include <linux/delay.h>
0013 #include <linux/init.h>
0014 #include <linux/kernel.h>
0015 #include <linux/platform_device.h>
0016 #include <linux/module.h>
0017 #include <linux/of.h>
0018 #include <linux/slab.h>
0019 #include <linux/device.h>
0020 #include <linux/err.h>
0021 #include <linux/gpio/consumer.h>
0022
0023 #include <linux/mmc/host.h>
0024
0025 #include "pwrseq.h"
0026
0027 struct mmc_pwrseq_sd8787 {
0028     struct mmc_pwrseq pwrseq;
0029     struct gpio_desc *reset_gpio;
0030     struct gpio_desc *pwrdn_gpio;
0031     u32 reset_pwrdwn_delay_ms;
0032 };
0033
0034 #define to_pwrseq_sd8787(p) container_of(p, struct mmc_pwrseq_sd8787, pwrseq)
0035
0036 static void mmc_pwrseq_sd8787_pre_power_on(struct mmc_host *host)
0037 {
0038     struct mmc_pwrseq_sd8787 *pwrseq = to_pwrseq_sd8787(host->pwrseq);
0039
0040     gpiod_set_value_cansleep(pwrseq->reset_gpio, 1);
0041
0042     msleep(pwrseq->reset_pwrdwn_delay_ms);
0043     gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 1);
0044 }
0045
0046 static void mmc_pwrseq_sd8787_power_off(struct mmc_host *host)
0047 {
0048     struct mmc_pwrseq_sd8787 *pwrseq = to_pwrseq_sd8787(host->pwrseq);
0049
0050     gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 0);
0051     gpiod_set_value_cansleep(pwrseq->reset_gpio, 0);
0052 }
0053
0054 static const struct mmc_pwrseq_ops mmc_pwrseq_sd8787_ops = {
0055     .pre_power_on = mmc_pwrseq_sd8787_pre_power_on,
0056     .power_off = mmc_pwrseq_sd8787_power_off,
0057 };
0058
0059 static const u32 sd8787_delay_ms = 300;
0060 static const u32 wilc1000_delay_ms = 5;
0061
0062 static const struct of_device_id mmc_pwrseq_sd8787_of_match[] = {
0063     { .compatible = "mmc-pwrseq-sd8787", .data = &sd8787_delay_ms },
0064     { .compatible = "mmc-pwrseq-wilc1000", .data = &wilc1000_delay_ms },
0065     {/* sentinel */},
0066 };
0067 MODULE_DEVICE_TABLE(of, mmc_pwrseq_sd8787_of_match);
0068
0069 static int mmc_pwrseq_sd8787_probe(struct platform_device *pdev)
0070 {
0071     struct mmc_pwrseq_sd8787 *pwrseq;
0072     struct device *dev = &pdev->dev;
0073     const struct of_device_id *match;
0074
0075     pwrseq = devm_kzalloc(dev, sizeof(*pwrseq), GFP_KERNEL);
0076     if (!pwrseq)
0077         return -ENOMEM;
0078
0079     match = of_match_node(mmc_pwrseq_sd8787_of_match, pdev->dev.of_node);
0080     pwrseq->reset_pwrdwn_delay_ms = *(u32 *)match->data;
0081
0082     pwrseq->pwrdn_gpio = devm_gpiod_get(dev, "powerdown", GPIOD_OUT_LOW);
0083     if (IS_ERR(pwrseq->pwrdn_gpio))
0084         return PTR_ERR(pwrseq->pwrdn_gpio);
0085
0086     pwrseq->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
0087     if (IS_ERR(pwrseq->reset_gpio))
0088         return PTR_ERR(pwrseq->reset_gpio);
0089
0090     pwrseq->pwrseq.dev = dev;
0091     pwrseq->pwrseq.ops = &mmc_pwrseq_sd8787_ops;
0092     pwrseq->pwrseq.owner = THIS_MODULE;
0093     platform_set_drvdata(pdev, pwrseq);
0094
0095     return mmc_pwrseq_register(&pwrseq->pwrseq);
0096 }
0097
0098 static int mmc_pwrseq_sd8787_remove(struct platform_device *pdev)
0099 {
0100     struct mmc_pwrseq_sd8787 *pwrseq = platform_get_drvdata(pdev);
0101
0102     mmc_pwrseq_unregister(&pwrseq->pwrseq);
0103
0104     return 0;
0105 }
0106
0107 static struct platform_driver mmc_pwrseq_sd8787_driver = {
0108     .probe = mmc_pwrseq_sd8787_probe,
0109     .remove = mmc_pwrseq_sd8787_remove,
0110     .driver = {
0111         .name = "pwrseq_sd8787",
0112         .of_match_table = mmc_pwrseq_sd8787_of_match,
0113     },
0114 };
0115
0116 module_platform_driver(mmc_pwrseq_sd8787_driver);
0117 MODULE_LICENSE("GPL v2");