summaryrefslogtreecommitdiffstats
path: root/drivers/gnss/ubx.c
blob: 902b6854b7db6a79fd8a566a2242c81522bf45a8 (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
/*
 * u-blox GNSS receiver driver
 *
 * Copyright (C) 2018 Johan Hovold <johan@kernel.org>
 */

#include <linux/errno.h>
#include <linux/gnss.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/regulator/consumer.h>
#include <linux/serdev.h>

#include "serial.h"

struct ubx_data {
	struct regulator *v_bckp;
	struct regulator *vcc;
};

static int ubx_set_active(struct gnss_serial *gserial)
{
	struct ubx_data *data = gnss_serial_get_drvdata(gserial);
	int ret;

	ret = regulator_enable(data->vcc);
	if (ret)
		return ret;

	return 0;
}

static int ubx_set_standby(struct gnss_serial *gserial)
{
	struct ubx_data *data = gnss_serial_get_drvdata(gserial);
	int ret;

	ret = regulator_disable(data->vcc);
	if (ret)
		return ret;

	return 0;
}

static int ubx_set_power(struct gnss_serial *gserial,
				enum gnss_serial_pm_state state)
{
	switch (state) {
	case GNSS_SERIAL_ACTIVE:
		return ubx_set_active(gserial);
	case GNSS_SERIAL_OFF:
	case GNSS_SERIAL_STANDBY:
		return ubx_set_standby(gserial);
	}

	return -EINVAL;
}

const struct gnss_serial_ops ubx_gserial_ops = {
	.set_power = ubx_set_power,
};

static int ubx_probe(struct serdev_device *serdev)
{
	struct gnss_serial *gserial;
	struct ubx_data *data;
	int ret;

	gserial = gnss_serial_allocate(serdev, sizeof(*data));
	if (IS_ERR(gserial)) {
		ret = PTR_ERR(gserial);
		return ret;
	}

	gserial->ops = &ubx_gserial_ops;

	gserial->gdev->type = GNSS_TYPE_UBX;

	data = gnss_serial_get_drvdata(gserial);

	data->vcc = devm_regulator_get(&serdev->dev, "vcc");
	if (IS_ERR(data->vcc)) {
		ret = PTR_ERR(data->vcc);
		goto err_free_gserial;
	}

	data->v_bckp = devm_regulator_get_optional(&serdev->dev, "v-bckp");
	if (IS_ERR(data->v_bckp)) {
		ret = PTR_ERR(data->v_bckp);
		if (ret == -ENODEV)
			data->v_bckp = NULL;
		else
			goto err_free_gserial;
	}

	if (data->v_bckp) {
		ret = regulator_enable(data->v_bckp);
		if (ret)
			goto err_free_gserial;
	}

	ret = gnss_serial_register(gserial);
	if (ret)
		goto err_disable_v_bckp;

	return 0;

err_disable_v_bckp:
	if (data->v_bckp)
		regulator_disable(data->v_bckp);
err_free_gserial:
	gnss_serial_free(gserial);

	return ret;
}

static void ubx_remove(struct serdev_device *serdev)
{
	struct gnss_serial *gserial = serdev_device_get_drvdata(serdev);
	struct ubx_data *data = gnss_serial_get_drvdata(gserial);

	gnss_serial_deregister(gserial);
	if (data->v_bckp)
		regulator_disable(data->v_bckp);
	gnss_serial_free(gserial);
};

#ifdef CONFIG_OF
static const struct of_device_id ubx_of_match[] = {
	{ .compatible = "u-blox,neo-8" },
	{ .compatible = "u-blox,neo-m8" },
	{},
};
MODULE_DEVICE_TABLE(of, ubx_of_match);
#endif

static struct serdev_device_driver ubx_driver = {
	.driver	= {
		.name		= "gnss-ubx",
		.of_match_table	= of_match_ptr(ubx_of_match),
		.pm		= &gnss_serial_pm_ops,
	},
	.probe	= ubx_probe,
	.remove	= ubx_remove,
};
module_serdev_device_driver(ubx_driver);

MODULE_AUTHOR("Johan Hovold <johan@kernel.org>");
MODULE_DESCRIPTION("u-blox GNSS receiver driver");
MODULE_LICENSE("GPL v2");