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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2014 Linaro Ltd
4 *
5 * Author: Ulf Hansson <ulf.hansson@linaro.org>
6 *
7 * MMC power sequence management
8 */
9#include <linux/kernel.h>
10#include <linux/err.h>
11#include <linux/module.h>
12#include <linux/of.h>
13
14#include <linux/mmc/host.h>
15
16#include "pwrseq.h"
17
18static DEFINE_MUTEX(pwrseq_list_mutex);
19static LIST_HEAD(pwrseq_list);
20
21int mmc_pwrseq_alloc(struct mmc_host *host)
22{
23 struct device_node *np;
24 struct mmc_pwrseq *p;
25
26 np = of_parse_phandle(host->parent->of_node, "mmc-pwrseq", 0);
27 if (!np)
28 return 0;
29
30 mutex_lock(&pwrseq_list_mutex);
31 list_for_each_entry(p, &pwrseq_list, pwrseq_node) {
32 if (device_match_of_node(p->dev, np)) {
33 if (!try_module_get(p->owner))
34 dev_err(host->parent,
35 "increasing module refcount failed\n");
36 else
37 host->pwrseq = p;
38
39 break;
40 }
41 }
42
43 of_node_put(np);
44 mutex_unlock(&pwrseq_list_mutex);
45
46 if (!host->pwrseq)
47 return -EPROBE_DEFER;
48
49 dev_info(host->parent, "allocated mmc-pwrseq\n");
50
51 return 0;
52}
53
54void mmc_pwrseq_pre_power_on(struct mmc_host *host)
55{
56 struct mmc_pwrseq *pwrseq = host->pwrseq;
57
58 if (pwrseq && pwrseq->ops->pre_power_on)
59 pwrseq->ops->pre_power_on(host);
60}
61
62void mmc_pwrseq_post_power_on(struct mmc_host *host)
63{
64 struct mmc_pwrseq *pwrseq = host->pwrseq;
65
66 if (pwrseq && pwrseq->ops->post_power_on)
67 pwrseq->ops->post_power_on(host);
68}
69
70void mmc_pwrseq_power_off(struct mmc_host *host)
71{
72 struct mmc_pwrseq *pwrseq = host->pwrseq;
73
74 if (pwrseq && pwrseq->ops->power_off)
75 pwrseq->ops->power_off(host);
76}
77
78void mmc_pwrseq_reset(struct mmc_host *host)
79{
80 struct mmc_pwrseq *pwrseq = host->pwrseq;
81
82 if (pwrseq && pwrseq->ops->reset)
83 pwrseq->ops->reset(host);
84}
85
86void mmc_pwrseq_free(struct mmc_host *host)
87{
88 struct mmc_pwrseq *pwrseq = host->pwrseq;
89
90 if (pwrseq) {
91 module_put(pwrseq->owner);
92 host->pwrseq = NULL;
93 }
94}
95
96int mmc_pwrseq_register(struct mmc_pwrseq *pwrseq)
97{
98 if (!pwrseq || !pwrseq->ops || !pwrseq->dev)
99 return -EINVAL;
100
101 mutex_lock(&pwrseq_list_mutex);
102 list_add(&pwrseq->pwrseq_node, &pwrseq_list);
103 mutex_unlock(&pwrseq_list_mutex);
104
105 return 0;
106}
107EXPORT_SYMBOL_GPL(mmc_pwrseq_register);
108
109void mmc_pwrseq_unregister(struct mmc_pwrseq *pwrseq)
110{
111 if (pwrseq) {
112 mutex_lock(&pwrseq_list_mutex);
113 list_del(&pwrseq->pwrseq_node);
114 mutex_unlock(&pwrseq_list_mutex);
115 }
116}
117EXPORT_SYMBOL_GPL(mmc_pwrseq_unregister);
1/*
2 * Copyright (C) 2014 Linaro Ltd
3 *
4 * Author: Ulf Hansson <ulf.hansson@linaro.org>
5 *
6 * License terms: GNU General Public License (GPL) version 2
7 *
8 * MMC power sequence management
9 */
10#include <linux/kernel.h>
11#include <linux/platform_device.h>
12#include <linux/err.h>
13#include <linux/of.h>
14#include <linux/of_platform.h>
15
16#include <linux/mmc/host.h>
17
18#include "pwrseq.h"
19
20struct mmc_pwrseq_match {
21 const char *compatible;
22 struct mmc_pwrseq *(*alloc)(struct mmc_host *host, struct device *dev);
23};
24
25static struct mmc_pwrseq_match pwrseq_match[] = {
26 {
27 .compatible = "mmc-pwrseq-simple",
28 .alloc = mmc_pwrseq_simple_alloc,
29 }, {
30 .compatible = "mmc-pwrseq-emmc",
31 .alloc = mmc_pwrseq_emmc_alloc,
32 },
33};
34
35static struct mmc_pwrseq_match *mmc_pwrseq_find(struct device_node *np)
36{
37 struct mmc_pwrseq_match *match = ERR_PTR(-ENODEV);
38 int i;
39
40 for (i = 0; i < ARRAY_SIZE(pwrseq_match); i++) {
41 if (of_device_is_compatible(np, pwrseq_match[i].compatible)) {
42 match = &pwrseq_match[i];
43 break;
44 }
45 }
46
47 return match;
48}
49
50int mmc_pwrseq_alloc(struct mmc_host *host)
51{
52 struct platform_device *pdev;
53 struct device_node *np;
54 struct mmc_pwrseq_match *match;
55 struct mmc_pwrseq *pwrseq;
56 int ret = 0;
57
58 np = of_parse_phandle(host->parent->of_node, "mmc-pwrseq", 0);
59 if (!np)
60 return 0;
61
62 pdev = of_find_device_by_node(np);
63 if (!pdev) {
64 ret = -ENODEV;
65 goto err;
66 }
67
68 match = mmc_pwrseq_find(np);
69 if (IS_ERR(match)) {
70 ret = PTR_ERR(match);
71 goto err;
72 }
73
74 pwrseq = match->alloc(host, &pdev->dev);
75 if (IS_ERR(pwrseq)) {
76 ret = PTR_ERR(pwrseq);
77 goto err;
78 }
79
80 host->pwrseq = pwrseq;
81 dev_info(host->parent, "allocated mmc-pwrseq\n");
82
83err:
84 of_node_put(np);
85 return ret;
86}
87
88void mmc_pwrseq_pre_power_on(struct mmc_host *host)
89{
90 struct mmc_pwrseq *pwrseq = host->pwrseq;
91
92 if (pwrseq && pwrseq->ops && pwrseq->ops->pre_power_on)
93 pwrseq->ops->pre_power_on(host);
94}
95
96void mmc_pwrseq_post_power_on(struct mmc_host *host)
97{
98 struct mmc_pwrseq *pwrseq = host->pwrseq;
99
100 if (pwrseq && pwrseq->ops && pwrseq->ops->post_power_on)
101 pwrseq->ops->post_power_on(host);
102}
103
104void mmc_pwrseq_power_off(struct mmc_host *host)
105{
106 struct mmc_pwrseq *pwrseq = host->pwrseq;
107
108 if (pwrseq && pwrseq->ops && pwrseq->ops->power_off)
109 pwrseq->ops->power_off(host);
110}
111
112void mmc_pwrseq_free(struct mmc_host *host)
113{
114 struct mmc_pwrseq *pwrseq = host->pwrseq;
115
116 if (pwrseq && pwrseq->ops && pwrseq->ops->free)
117 pwrseq->ops->free(host);
118
119 host->pwrseq = NULL;
120}