OpenCloudOS-Kernel/drivers/gnss/mtk.c

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// SPDX-License-Identifier: GPL-2.0
/*
* Mediatek 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 mtk_data {
struct regulator *vbackup;
struct regulator *vcc;
};
static int mtk_set_active(struct gnss_serial *gserial)
{
struct mtk_data *data = gnss_serial_get_drvdata(gserial);
int ret;
ret = regulator_enable(data->vcc);
if (ret)
return ret;
return 0;
}
static int mtk_set_standby(struct gnss_serial *gserial)
{
struct mtk_data *data = gnss_serial_get_drvdata(gserial);
int ret;
ret = regulator_disable(data->vcc);
if (ret)
return ret;
return 0;
}
static int mtk_set_power(struct gnss_serial *gserial,
enum gnss_serial_pm_state state)
{
switch (state) {
case GNSS_SERIAL_ACTIVE:
return mtk_set_active(gserial);
case GNSS_SERIAL_OFF:
case GNSS_SERIAL_STANDBY:
return mtk_set_standby(gserial);
}
return -EINVAL;
}
static const struct gnss_serial_ops mtk_gserial_ops = {
.set_power = mtk_set_power,
};
static int mtk_probe(struct serdev_device *serdev)
{
struct gnss_serial *gserial;
struct mtk_data *data;
int ret;
gserial = gnss_serial_allocate(serdev, sizeof(*data));
if (IS_ERR(gserial)) {
ret = PTR_ERR(gserial);
return ret;
}
gserial->ops = &mtk_gserial_ops;
gserial->gdev->type = GNSS_TYPE_MTK;
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->vbackup = devm_regulator_get_optional(&serdev->dev, "vbackup");
if (IS_ERR(data->vbackup)) {
ret = PTR_ERR(data->vbackup);
if (ret == -ENODEV)
data->vbackup = NULL;
else
goto err_free_gserial;
}
if (data->vbackup) {
ret = regulator_enable(data->vbackup);
if (ret)
goto err_free_gserial;
}
ret = gnss_serial_register(gserial);
if (ret)
goto err_disable_vbackup;
return 0;
err_disable_vbackup:
if (data->vbackup)
regulator_disable(data->vbackup);
err_free_gserial:
gnss_serial_free(gserial);
return ret;
}
static void mtk_remove(struct serdev_device *serdev)
{
struct gnss_serial *gserial = serdev_device_get_drvdata(serdev);
struct mtk_data *data = gnss_serial_get_drvdata(gserial);
gnss_serial_deregister(gserial);
if (data->vbackup)
regulator_disable(data->vbackup);
gnss_serial_free(gserial);
};
#ifdef CONFIG_OF
static const struct of_device_id mtk_of_match[] = {
{ .compatible = "globaltop,pa6h" },
{},
};
MODULE_DEVICE_TABLE(of, mtk_of_match);
#endif
static struct serdev_device_driver mtk_driver = {
.driver = {
.name = "gnss-mtk",
.of_match_table = of_match_ptr(mtk_of_match),
.pm = &gnss_serial_pm_ops,
},
.probe = mtk_probe,
.remove = mtk_remove,
};
module_serdev_device_driver(mtk_driver);
MODULE_AUTHOR("Loys Ollivier <lollivier@baylibre.com>");
MODULE_DESCRIPTION("Mediatek GNSS receiver driver");
MODULE_LICENSE("GPL v2");