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/gpio/consumer.h> |
11 | #include <linux/init.h> |
12 | #include <linux/kernel.h> |
13 | #include <linux/module.h> |
14 | #include <linux/of.h> |
15 | #include <linux/regulator/consumer.h> |
16 | #include <linux/serdev.h> |
17 | |
18 | #include "serial.h" |
19 | |
20 | struct ubx_data { |
21 | struct regulator *vcc; |
22 | }; |
23 | |
24 | static 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(regulator: data->vcc); |
30 | if (ret) |
31 | return ret; |
32 | |
33 | return 0; |
34 | } |
35 | |
36 | static 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(regulator: data->vcc); |
42 | if (ret) |
43 | return ret; |
44 | |
45 | return 0; |
46 | } |
47 | |
48 | static 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 | |
62 | static const struct gnss_serial_ops ubx_gserial_ops = { |
63 | .set_power = ubx_set_power, |
64 | }; |
65 | |
66 | static int ubx_probe(struct serdev_device *serdev) |
67 | { |
68 | struct gnss_serial *gserial; |
69 | struct gpio_desc *reset; |
70 | struct ubx_data *data; |
71 | int ret; |
72 | |
73 | gserial = gnss_serial_allocate(gserial: serdev, data_size: sizeof(*data)); |
74 | if (IS_ERR(ptr: gserial)) { |
75 | ret = PTR_ERR(ptr: gserial); |
76 | return ret; |
77 | } |
78 | |
79 | gserial->ops = &ubx_gserial_ops; |
80 | |
81 | gserial->gdev->type = GNSS_TYPE_UBX; |
82 | |
83 | data = gnss_serial_get_drvdata(gserial); |
84 | |
85 | data->vcc = devm_regulator_get(dev: &serdev->dev, id: "vcc" ); |
86 | if (IS_ERR(ptr: data->vcc)) { |
87 | ret = PTR_ERR(ptr: data->vcc); |
88 | goto err_free_gserial; |
89 | } |
90 | |
91 | ret = devm_regulator_get_enable_optional(dev: &serdev->dev, id: "v-bckp" ); |
92 | if (ret < 0 && ret != -ENODEV) |
93 | goto err_free_gserial; |
94 | |
95 | /* Deassert reset */ |
96 | reset = devm_gpiod_get_optional(dev: &serdev->dev, con_id: "reset" , flags: GPIOD_OUT_LOW); |
97 | if (IS_ERR(ptr: reset)) { |
98 | ret = PTR_ERR(ptr: reset); |
99 | goto err_free_gserial; |
100 | } |
101 | |
102 | ret = gnss_serial_register(gserial); |
103 | if (ret) |
104 | goto err_free_gserial; |
105 | |
106 | return 0; |
107 | |
108 | err_free_gserial: |
109 | gnss_serial_free(gserial); |
110 | |
111 | return ret; |
112 | } |
113 | |
114 | static void ubx_remove(struct serdev_device *serdev) |
115 | { |
116 | struct gnss_serial *gserial = serdev_device_get_drvdata(serdev); |
117 | |
118 | gnss_serial_deregister(gserial); |
119 | gnss_serial_free(gserial); |
120 | } |
121 | |
122 | #ifdef CONFIG_OF |
123 | static const struct of_device_id ubx_of_match[] = { |
124 | { .compatible = "u-blox,neo-6m" }, |
125 | { .compatible = "u-blox,neo-8" }, |
126 | { .compatible = "u-blox,neo-m8" }, |
127 | {}, |
128 | }; |
129 | MODULE_DEVICE_TABLE(of, ubx_of_match); |
130 | #endif |
131 | |
132 | static struct serdev_device_driver ubx_driver = { |
133 | .driver = { |
134 | .name = "gnss-ubx" , |
135 | .of_match_table = of_match_ptr(ubx_of_match), |
136 | .pm = &gnss_serial_pm_ops, |
137 | }, |
138 | .probe = ubx_probe, |
139 | .remove = ubx_remove, |
140 | }; |
141 | module_serdev_device_driver(ubx_driver); |
142 | |
143 | MODULE_AUTHOR("Johan Hovold <johan@kernel.org>" ); |
144 | MODULE_DESCRIPTION("u-blox GNSS receiver driver" ); |
145 | MODULE_LICENSE("GPL v2" ); |
146 | |