1// SPDX-License-Identifier: GPL-2.0
2/*
3 * u-blox GNSS receiver driver
4 *
5 * Copyright (C) 2018 Johan Hovold <johan@kernel.org>
6 */
7
8#include <linux/errno.h>
9#include <linux/gnss.h>
10#include <linux/init.h>
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/of.h>
14#include <linux/regulator/consumer.h>
15#include <linux/serdev.h>
16
17#include "serial.h"
18
19struct ubx_data {
20 struct regulator *v_bckp;
21 struct regulator *vcc;
22};
23
24static int ubx_set_active(struct gnss_serial *gserial)
25{
26 struct ubx_data *data = gnss_serial_get_drvdata(gserial);
27 int ret;
28
29 ret = regulator_enable(data->vcc);
30 if (ret)
31 return ret;
32
33 return 0;
34}
35
36static int ubx_set_standby(struct gnss_serial *gserial)
37{
38 struct ubx_data *data = gnss_serial_get_drvdata(gserial);
39 int ret;
40
41 ret = regulator_disable(data->vcc);
42 if (ret)
43 return ret;
44
45 return 0;
46}
47
48static int ubx_set_power(struct gnss_serial *gserial,
49 enum gnss_serial_pm_state state)
50{
51 switch (state) {
52 case GNSS_SERIAL_ACTIVE:
53 return ubx_set_active(gserial);
54 case GNSS_SERIAL_OFF:
55 case GNSS_SERIAL_STANDBY:
56 return ubx_set_standby(gserial);
57 }
58
59 return -EINVAL;
60}
61
62static const struct gnss_serial_ops ubx_gserial_ops = {
63 .set_power = ubx_set_power,
64};
65
66static int ubx_probe(struct serdev_device *serdev)
67{
68 struct gnss_serial *gserial;
69 struct ubx_data *data;
70 int ret;
71
72 gserial = gnss_serial_allocate(serdev, sizeof(*data));
73 if (IS_ERR(gserial)) {
74 ret = PTR_ERR(gserial);
75 return ret;
76 }
77
78 gserial->ops = &ubx_gserial_ops;
79
80 gserial->gdev->type = GNSS_TYPE_UBX;
81
82 data = gnss_serial_get_drvdata(gserial);
83
84 data->vcc = devm_regulator_get(&serdev->dev, "vcc");
85 if (IS_ERR(data->vcc)) {
86 ret = PTR_ERR(data->vcc);
87 goto err_free_gserial;
88 }
89
90 data->v_bckp = devm_regulator_get_optional(&serdev->dev, "v-bckp");
91 if (IS_ERR(data->v_bckp)) {
92 ret = PTR_ERR(data->v_bckp);
93 if (ret == -ENODEV)
94 data->v_bckp = NULL;
95 else
96 goto err_free_gserial;
97 }
98
99 if (data->v_bckp) {
100 ret = regulator_enable(data->v_bckp);
101 if (ret)
102 goto err_free_gserial;
103 }
104
105 ret = gnss_serial_register(gserial);
106 if (ret)
107 goto err_disable_v_bckp;
108
109 return 0;
110
111err_disable_v_bckp:
112 if (data->v_bckp)
113 regulator_disable(data->v_bckp);
114err_free_gserial:
115 gnss_serial_free(gserial);
116
117 return ret;
118}
119
120static void ubx_remove(struct serdev_device *serdev)
121{
122 struct gnss_serial *gserial = serdev_device_get_drvdata(serdev);
123 struct ubx_data *data = gnss_serial_get_drvdata(gserial);
124
125 gnss_serial_deregister(gserial);
126 if (data->v_bckp)
127 regulator_disable(data->v_bckp);
128 gnss_serial_free(gserial);
129};
130
131#ifdef CONFIG_OF
132static const struct of_device_id ubx_of_match[] = {
133 { .compatible = "u-blox,neo-8" },
134 { .compatible = "u-blox,neo-m8" },
135 {},
136};
137MODULE_DEVICE_TABLE(of, ubx_of_match);
138#endif
139
140static struct serdev_device_driver ubx_driver = {
141 .driver = {
142 .name = "gnss-ubx",
143 .of_match_table = of_match_ptr(ubx_of_match),
144 .pm = &gnss_serial_pm_ops,
145 },
146 .probe = ubx_probe,
147 .remove = ubx_remove,
148};
149module_serdev_device_driver(ubx_driver);
150
151MODULE_AUTHOR("Johan Hovold <johan@kernel.org>");
152MODULE_DESCRIPTION("u-blox GNSS receiver driver");
153MODULE_LICENSE("GPL v2");
154