xref: /openbmc/linux/drivers/mmc/core/pwrseq_sd8787.c (revision 7e9f2839)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * pwrseq_sd8787.c - power sequence support for Marvell SD8787 BT + Wifi chip
4  *
5  * Copyright (C) 2016 Matt Ranostay <matt@ranostay.consulting>
6  *
7  * Based on the original work pwrseq_simple.c
8  *  Copyright (C) 2014 Linaro Ltd
9  *  Author: Ulf Hansson <ulf.hansson@linaro.org>
10  */
11 
12 #include <linux/delay.h>
13 #include <linux/init.h>
14 #include <linux/kernel.h>
15 #include <linux/platform_device.h>
16 #include <linux/module.h>
17 #include <linux/of.h>
18 #include <linux/slab.h>
19 #include <linux/device.h>
20 #include <linux/err.h>
21 #include <linux/gpio/consumer.h>
22 
23 #include <linux/mmc/host.h>
24 
25 #include "pwrseq.h"
26 
27 struct mmc_pwrseq_sd8787 {
28 	struct mmc_pwrseq pwrseq;
29 	struct gpio_desc *reset_gpio;
30 	struct gpio_desc *pwrdn_gpio;
31 };
32 
33 #define to_pwrseq_sd8787(p) container_of(p, struct mmc_pwrseq_sd8787, pwrseq)
34 
35 static void mmc_pwrseq_sd8787_pre_power_on(struct mmc_host *host)
36 {
37 	struct mmc_pwrseq_sd8787 *pwrseq = to_pwrseq_sd8787(host->pwrseq);
38 
39 	gpiod_set_value_cansleep(pwrseq->reset_gpio, 1);
40 
41 	msleep(300);
42 	gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 1);
43 }
44 
45 static void mmc_pwrseq_sd8787_power_off(struct mmc_host *host)
46 {
47 	struct mmc_pwrseq_sd8787 *pwrseq = to_pwrseq_sd8787(host->pwrseq);
48 
49 	gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 0);
50 	gpiod_set_value_cansleep(pwrseq->reset_gpio, 0);
51 }
52 
53 static void mmc_pwrseq_wilc1000_pre_power_on(struct mmc_host *host)
54 {
55 	struct mmc_pwrseq_sd8787 *pwrseq = to_pwrseq_sd8787(host->pwrseq);
56 
57 	/* The pwrdn_gpio is really CHIP_EN, reset_gpio is RESETN */
58 	gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 1);
59 	msleep(5);
60 	gpiod_set_value_cansleep(pwrseq->reset_gpio, 1);
61 }
62 
63 static void mmc_pwrseq_wilc1000_power_off(struct mmc_host *host)
64 {
65 	struct mmc_pwrseq_sd8787 *pwrseq = to_pwrseq_sd8787(host->pwrseq);
66 
67 	gpiod_set_value_cansleep(pwrseq->reset_gpio, 0);
68 	gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 0);
69 }
70 
71 static const struct mmc_pwrseq_ops mmc_pwrseq_sd8787_ops = {
72 	.pre_power_on = mmc_pwrseq_sd8787_pre_power_on,
73 	.power_off = mmc_pwrseq_sd8787_power_off,
74 };
75 
76 static const struct mmc_pwrseq_ops mmc_pwrseq_wilc1000_ops = {
77 	.pre_power_on = mmc_pwrseq_wilc1000_pre_power_on,
78 	.power_off = mmc_pwrseq_wilc1000_power_off,
79 };
80 
81 static const struct of_device_id mmc_pwrseq_sd8787_of_match[] = {
82 	{ .compatible = "mmc-pwrseq-sd8787", .data = &mmc_pwrseq_sd8787_ops },
83 	{ .compatible = "mmc-pwrseq-wilc1000", .data = &mmc_pwrseq_wilc1000_ops },
84 	{/* sentinel */},
85 };
86 MODULE_DEVICE_TABLE(of, mmc_pwrseq_sd8787_of_match);
87 
88 static int mmc_pwrseq_sd8787_probe(struct platform_device *pdev)
89 {
90 	struct mmc_pwrseq_sd8787 *pwrseq;
91 	struct device *dev = &pdev->dev;
92 	const struct of_device_id *match;
93 
94 	pwrseq = devm_kzalloc(dev, sizeof(*pwrseq), GFP_KERNEL);
95 	if (!pwrseq)
96 		return -ENOMEM;
97 
98 	match = of_match_node(mmc_pwrseq_sd8787_of_match, pdev->dev.of_node);
99 
100 	pwrseq->pwrdn_gpio = devm_gpiod_get(dev, "powerdown", GPIOD_OUT_LOW);
101 	if (IS_ERR(pwrseq->pwrdn_gpio))
102 		return PTR_ERR(pwrseq->pwrdn_gpio);
103 
104 	pwrseq->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
105 	if (IS_ERR(pwrseq->reset_gpio))
106 		return PTR_ERR(pwrseq->reset_gpio);
107 
108 	pwrseq->pwrseq.dev = dev;
109 	pwrseq->pwrseq.ops = match->data;
110 	pwrseq->pwrseq.owner = THIS_MODULE;
111 	platform_set_drvdata(pdev, pwrseq);
112 
113 	return mmc_pwrseq_register(&pwrseq->pwrseq);
114 }
115 
116 static int mmc_pwrseq_sd8787_remove(struct platform_device *pdev)
117 {
118 	struct mmc_pwrseq_sd8787 *pwrseq = platform_get_drvdata(pdev);
119 
120 	mmc_pwrseq_unregister(&pwrseq->pwrseq);
121 
122 	return 0;
123 }
124 
125 static struct platform_driver mmc_pwrseq_sd8787_driver = {
126 	.probe = mmc_pwrseq_sd8787_probe,
127 	.remove = mmc_pwrseq_sd8787_remove,
128 	.driver = {
129 		.name = "pwrseq_sd8787",
130 		.of_match_table = mmc_pwrseq_sd8787_of_match,
131 	},
132 };
133 
134 module_platform_driver(mmc_pwrseq_sd8787_driver);
135 MODULE_LICENSE("GPL v2");
136