1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Mediatek GNSS receiver driver
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (C) 2018 Johan Hovold <johan@kernel.org>
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #include <linux/errno.h>
9*4882a593Smuzhiyun #include <linux/gnss.h>
10*4882a593Smuzhiyun #include <linux/init.h>
11*4882a593Smuzhiyun #include <linux/kernel.h>
12*4882a593Smuzhiyun #include <linux/module.h>
13*4882a593Smuzhiyun #include <linux/of.h>
14*4882a593Smuzhiyun #include <linux/regulator/consumer.h>
15*4882a593Smuzhiyun #include <linux/serdev.h>
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun #include "serial.h"
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun struct mtk_data {
20*4882a593Smuzhiyun struct regulator *vbackup;
21*4882a593Smuzhiyun struct regulator *vcc;
22*4882a593Smuzhiyun };
23*4882a593Smuzhiyun
mtk_set_active(struct gnss_serial * gserial)24*4882a593Smuzhiyun static int mtk_set_active(struct gnss_serial *gserial)
25*4882a593Smuzhiyun {
26*4882a593Smuzhiyun struct mtk_data *data = gnss_serial_get_drvdata(gserial);
27*4882a593Smuzhiyun int ret;
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun ret = regulator_enable(data->vcc);
30*4882a593Smuzhiyun if (ret)
31*4882a593Smuzhiyun return ret;
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun return 0;
34*4882a593Smuzhiyun }
35*4882a593Smuzhiyun
mtk_set_standby(struct gnss_serial * gserial)36*4882a593Smuzhiyun static int mtk_set_standby(struct gnss_serial *gserial)
37*4882a593Smuzhiyun {
38*4882a593Smuzhiyun struct mtk_data *data = gnss_serial_get_drvdata(gserial);
39*4882a593Smuzhiyun int ret;
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun ret = regulator_disable(data->vcc);
42*4882a593Smuzhiyun if (ret)
43*4882a593Smuzhiyun return ret;
44*4882a593Smuzhiyun
45*4882a593Smuzhiyun return 0;
46*4882a593Smuzhiyun }
47*4882a593Smuzhiyun
mtk_set_power(struct gnss_serial * gserial,enum gnss_serial_pm_state state)48*4882a593Smuzhiyun static int mtk_set_power(struct gnss_serial *gserial,
49*4882a593Smuzhiyun enum gnss_serial_pm_state state)
50*4882a593Smuzhiyun {
51*4882a593Smuzhiyun switch (state) {
52*4882a593Smuzhiyun case GNSS_SERIAL_ACTIVE:
53*4882a593Smuzhiyun return mtk_set_active(gserial);
54*4882a593Smuzhiyun case GNSS_SERIAL_OFF:
55*4882a593Smuzhiyun case GNSS_SERIAL_STANDBY:
56*4882a593Smuzhiyun return mtk_set_standby(gserial);
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun return -EINVAL;
60*4882a593Smuzhiyun }
61*4882a593Smuzhiyun
62*4882a593Smuzhiyun static const struct gnss_serial_ops mtk_gserial_ops = {
63*4882a593Smuzhiyun .set_power = mtk_set_power,
64*4882a593Smuzhiyun };
65*4882a593Smuzhiyun
mtk_probe(struct serdev_device * serdev)66*4882a593Smuzhiyun static int mtk_probe(struct serdev_device *serdev)
67*4882a593Smuzhiyun {
68*4882a593Smuzhiyun struct gnss_serial *gserial;
69*4882a593Smuzhiyun struct mtk_data *data;
70*4882a593Smuzhiyun int ret;
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun gserial = gnss_serial_allocate(serdev, sizeof(*data));
73*4882a593Smuzhiyun if (IS_ERR(gserial)) {
74*4882a593Smuzhiyun ret = PTR_ERR(gserial);
75*4882a593Smuzhiyun return ret;
76*4882a593Smuzhiyun }
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun gserial->ops = &mtk_gserial_ops;
79*4882a593Smuzhiyun
80*4882a593Smuzhiyun gserial->gdev->type = GNSS_TYPE_MTK;
81*4882a593Smuzhiyun
82*4882a593Smuzhiyun data = gnss_serial_get_drvdata(gserial);
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun data->vcc = devm_regulator_get(&serdev->dev, "vcc");
85*4882a593Smuzhiyun if (IS_ERR(data->vcc)) {
86*4882a593Smuzhiyun ret = PTR_ERR(data->vcc);
87*4882a593Smuzhiyun goto err_free_gserial;
88*4882a593Smuzhiyun }
89*4882a593Smuzhiyun
90*4882a593Smuzhiyun data->vbackup = devm_regulator_get_optional(&serdev->dev, "vbackup");
91*4882a593Smuzhiyun if (IS_ERR(data->vbackup)) {
92*4882a593Smuzhiyun ret = PTR_ERR(data->vbackup);
93*4882a593Smuzhiyun if (ret == -ENODEV)
94*4882a593Smuzhiyun data->vbackup = NULL;
95*4882a593Smuzhiyun else
96*4882a593Smuzhiyun goto err_free_gserial;
97*4882a593Smuzhiyun }
98*4882a593Smuzhiyun
99*4882a593Smuzhiyun if (data->vbackup) {
100*4882a593Smuzhiyun ret = regulator_enable(data->vbackup);
101*4882a593Smuzhiyun if (ret)
102*4882a593Smuzhiyun goto err_free_gserial;
103*4882a593Smuzhiyun }
104*4882a593Smuzhiyun
105*4882a593Smuzhiyun ret = gnss_serial_register(gserial);
106*4882a593Smuzhiyun if (ret)
107*4882a593Smuzhiyun goto err_disable_vbackup;
108*4882a593Smuzhiyun
109*4882a593Smuzhiyun return 0;
110*4882a593Smuzhiyun
111*4882a593Smuzhiyun err_disable_vbackup:
112*4882a593Smuzhiyun if (data->vbackup)
113*4882a593Smuzhiyun regulator_disable(data->vbackup);
114*4882a593Smuzhiyun err_free_gserial:
115*4882a593Smuzhiyun gnss_serial_free(gserial);
116*4882a593Smuzhiyun
117*4882a593Smuzhiyun return ret;
118*4882a593Smuzhiyun }
119*4882a593Smuzhiyun
mtk_remove(struct serdev_device * serdev)120*4882a593Smuzhiyun static void mtk_remove(struct serdev_device *serdev)
121*4882a593Smuzhiyun {
122*4882a593Smuzhiyun struct gnss_serial *gserial = serdev_device_get_drvdata(serdev);
123*4882a593Smuzhiyun struct mtk_data *data = gnss_serial_get_drvdata(gserial);
124*4882a593Smuzhiyun
125*4882a593Smuzhiyun gnss_serial_deregister(gserial);
126*4882a593Smuzhiyun if (data->vbackup)
127*4882a593Smuzhiyun regulator_disable(data->vbackup);
128*4882a593Smuzhiyun gnss_serial_free(gserial);
129*4882a593Smuzhiyun };
130*4882a593Smuzhiyun
131*4882a593Smuzhiyun #ifdef CONFIG_OF
132*4882a593Smuzhiyun static const struct of_device_id mtk_of_match[] = {
133*4882a593Smuzhiyun { .compatible = "globaltop,pa6h" },
134*4882a593Smuzhiyun {},
135*4882a593Smuzhiyun };
136*4882a593Smuzhiyun MODULE_DEVICE_TABLE(of, mtk_of_match);
137*4882a593Smuzhiyun #endif
138*4882a593Smuzhiyun
139*4882a593Smuzhiyun static struct serdev_device_driver mtk_driver = {
140*4882a593Smuzhiyun .driver = {
141*4882a593Smuzhiyun .name = "gnss-mtk",
142*4882a593Smuzhiyun .of_match_table = of_match_ptr(mtk_of_match),
143*4882a593Smuzhiyun .pm = &gnss_serial_pm_ops,
144*4882a593Smuzhiyun },
145*4882a593Smuzhiyun .probe = mtk_probe,
146*4882a593Smuzhiyun .remove = mtk_remove,
147*4882a593Smuzhiyun };
148*4882a593Smuzhiyun module_serdev_device_driver(mtk_driver);
149*4882a593Smuzhiyun
150*4882a593Smuzhiyun MODULE_AUTHOR("Loys Ollivier <lollivier@baylibre.com>");
151*4882a593Smuzhiyun MODULE_DESCRIPTION("Mediatek GNSS receiver driver");
152*4882a593Smuzhiyun MODULE_LICENSE("GPL v2");
153