summaryrefslogtreecommitdiffstats
path: root/drivers/pmdomain/arm/scmi_pm_domain.c
blob: 0e05a79de82d8ad6e080ada9f12f87f2715dc7ad (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
// SPDX-License-Identifier: GPL-2.0
/*
 * SCMI Generic power domain support.
 *
 * Copyright (C) 2018-2021 ARM Ltd.
 */

#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/pm_domain.h>
#include <linux/scmi_protocol.h>

static const struct scmi_power_proto_ops *power_ops;

struct scmi_pm_domain {
	struct generic_pm_domain genpd;
	const struct scmi_protocol_handle *ph;
	const char *name;
	u32 domain;
};

#define to_scmi_pd(gpd) container_of(gpd, struct scmi_pm_domain, genpd)

static int scmi_pd_power(struct generic_pm_domain *domain, bool power_on)
{
	int ret;
	u32 state, ret_state;
	struct scmi_pm_domain *pd = to_scmi_pd(domain);

	if (power_on)
		state = SCMI_POWER_STATE_GENERIC_ON;
	else
		state = SCMI_POWER_STATE_GENERIC_OFF;

	ret = power_ops->state_set(pd->ph, pd->domain, state);
	if (!ret)
		ret = power_ops->state_get(pd->ph, pd->domain, &ret_state);
	if (!ret && state != ret_state)
		return -EIO;

	return ret;
}

static int scmi_pd_power_on(struct generic_pm_domain *domain)
{
	return scmi_pd_power(domain, true);
}

static int scmi_pd_power_off(struct generic_pm_domain *domain)
{
	return scmi_pd_power(domain, false);
}

static int scmi_pm_domain_probe(struct scmi_device *sdev)
{
	int num_domains, i;
	struct device *dev = &sdev->dev;
	struct device_node *np = dev->of_node;
	struct scmi_pm_domain *scmi_pd;
	struct genpd_onecell_data *scmi_pd_data;
	struct generic_pm_domain **domains;
	const struct scmi_handle *handle = sdev->handle;
	struct scmi_protocol_handle *ph;

	if (!handle)
		return -ENODEV;

	power_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_POWER, &ph);
	if (IS_ERR(power_ops))
		return PTR_ERR(power_ops);

	num_domains = power_ops->num_domains_get(ph);
	if (num_domains < 0) {
		dev_err(dev, "number of domains not found\n");
		return num_domains;
	}

	scmi_pd = devm_kcalloc(dev, num_domains, sizeof(*scmi_pd), GFP_KERNEL);
	if (!scmi_pd)
		return -ENOMEM;

	scmi_pd_data = devm_kzalloc(dev, sizeof(*scmi_pd_data), GFP_KERNEL);
	if (!scmi_pd_data)
		return -ENOMEM;

	domains = devm_kcalloc(dev, num_domains, sizeof(*domains), GFP_KERNEL);
	if (!domains)
		return -ENOMEM;

	for (i = 0; i < num_domains; i++, scmi_pd++) {
		u32 state;

		if (power_ops->state_get(ph, i, &state)) {
			dev_warn(dev, "failed to get state for domain %d\n", i);
			continue;
		}

		scmi_pd->domain = i;
		scmi_pd->ph = ph;
		scmi_pd->name = power_ops->name_get(ph, i);
		scmi_pd->genpd.name = scmi_pd->name;
		scmi_pd->genpd.power_off = scmi_pd_power_off;
		scmi_pd->genpd.power_on = scmi_pd_power_on;

		pm_genpd_init(&scmi_pd->genpd, NULL,
			      state == SCMI_POWER_STATE_GENERIC_OFF);

		domains[i] = &scmi_pd->genpd;
	}

	scmi_pd_data->domains = domains;
	scmi_pd_data->num_domains = num_domains;

	dev_set_drvdata(dev, scmi_pd_data);

	return of_genpd_add_provider_onecell(np, scmi_pd_data);
}

static void scmi_pm_domain_remove(struct scmi_device *sdev)
{
	int i;
	struct genpd_onecell_data *scmi_pd_data;
	struct device *dev = &sdev->dev;
	struct device_node *np = dev->of_node;

	of_genpd_del_provider(np);

	scmi_pd_data = dev_get_drvdata(dev);
	for (i = 0; i < scmi_pd_data->num_domains; i++) {
		if (!scmi_pd_data->domains[i])
			continue;
		pm_genpd_remove(scmi_pd_data->domains[i]);
	}
}

static const struct scmi_device_id scmi_id_table[] = {
	{ SCMI_PROTOCOL_POWER, "genpd" },
	{ },
};
MODULE_DEVICE_TABLE(scmi, scmi_id_table);

static struct scmi_driver scmi_power_domain_driver = {
	.name = "scmi-power-domain",
	.probe = scmi_pm_domain_probe,
	.remove = scmi_pm_domain_remove,
	.id_table = scmi_id_table,
};
module_scmi_driver(scmi_power_domain_driver);

MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
MODULE_DESCRIPTION("ARM SCMI power domain driver");
MODULE_LICENSE("GPL v2");