153 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			153 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| /*
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|  * Mediatek GNSS receiver driver
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|  *
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|  * Copyright (C) 2018 Johan Hovold <johan@kernel.org>
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|  */
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| 
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| #include <linux/errno.h>
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| #include <linux/gnss.h>
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| #include <linux/init.h>
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| #include <linux/kernel.h>
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| #include <linux/module.h>
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| #include <linux/of.h>
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| #include <linux/regulator/consumer.h>
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| #include <linux/serdev.h>
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| 
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| #include "serial.h"
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| 
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| struct mtk_data {
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| 	struct regulator *vbackup;
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| 	struct regulator *vcc;
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| };
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| 
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| static int mtk_set_active(struct gnss_serial *gserial)
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| {
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| 	struct mtk_data *data = gnss_serial_get_drvdata(gserial);
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| 	int ret;
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| 
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| 	ret = regulator_enable(data->vcc);
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| 	if (ret)
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| 		return ret;
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| 
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| 	return 0;
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| }
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| 
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| static int mtk_set_standby(struct gnss_serial *gserial)
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| {
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| 	struct mtk_data *data = gnss_serial_get_drvdata(gserial);
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| 	int ret;
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| 
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| 	ret = regulator_disable(data->vcc);
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| 	if (ret)
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| 		return ret;
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| 
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| 	return 0;
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| }
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| 
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| static int mtk_set_power(struct gnss_serial *gserial,
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| 			 enum gnss_serial_pm_state state)
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| {
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| 	switch (state) {
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| 	case GNSS_SERIAL_ACTIVE:
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| 		return mtk_set_active(gserial);
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| 	case GNSS_SERIAL_OFF:
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| 	case GNSS_SERIAL_STANDBY:
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| 		return mtk_set_standby(gserial);
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| 	}
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| 
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| 	return -EINVAL;
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| }
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| 
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| static const struct gnss_serial_ops mtk_gserial_ops = {
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| 	.set_power = mtk_set_power,
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| };
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| 
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| static int mtk_probe(struct serdev_device *serdev)
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| {
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| 	struct gnss_serial *gserial;
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| 	struct mtk_data *data;
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| 	int ret;
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| 
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| 	gserial = gnss_serial_allocate(serdev, sizeof(*data));
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| 	if (IS_ERR(gserial)) {
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| 		ret = PTR_ERR(gserial);
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| 		return ret;
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| 	}
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| 
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| 	gserial->ops = &mtk_gserial_ops;
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| 
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| 	gserial->gdev->type = GNSS_TYPE_MTK;
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| 
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| 	data = gnss_serial_get_drvdata(gserial);
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| 
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| 	data->vcc = devm_regulator_get(&serdev->dev, "vcc");
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| 	if (IS_ERR(data->vcc)) {
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| 		ret = PTR_ERR(data->vcc);
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| 		goto err_free_gserial;
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| 	}
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| 
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| 	data->vbackup = devm_regulator_get_optional(&serdev->dev, "vbackup");
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| 	if (IS_ERR(data->vbackup)) {
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| 		ret = PTR_ERR(data->vbackup);
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| 		if (ret == -ENODEV)
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| 			data->vbackup = NULL;
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| 		else
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| 			goto err_free_gserial;
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| 	}
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| 
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| 	if (data->vbackup) {
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| 		ret = regulator_enable(data->vbackup);
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| 		if (ret)
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| 			goto err_free_gserial;
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| 	}
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| 
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| 	ret = gnss_serial_register(gserial);
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| 	if (ret)
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| 		goto err_disable_vbackup;
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| 
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| 	return 0;
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| 
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| err_disable_vbackup:
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| 	if (data->vbackup)
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| 		regulator_disable(data->vbackup);
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| err_free_gserial:
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| 	gnss_serial_free(gserial);
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| 
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| 	return ret;
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| }
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| 
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| static void mtk_remove(struct serdev_device *serdev)
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| {
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| 	struct gnss_serial *gserial = serdev_device_get_drvdata(serdev);
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| 	struct mtk_data *data = gnss_serial_get_drvdata(gserial);
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| 
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| 	gnss_serial_deregister(gserial);
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| 	if (data->vbackup)
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| 		regulator_disable(data->vbackup);
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| 	gnss_serial_free(gserial);
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| };
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| 
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| #ifdef CONFIG_OF
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| static const struct of_device_id mtk_of_match[] = {
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| 	{ .compatible = "globaltop,pa6h" },
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| 	{},
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| };
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| MODULE_DEVICE_TABLE(of, mtk_of_match);
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| #endif
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| 
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| static struct serdev_device_driver mtk_driver = {
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| 	.driver	= {
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| 		.name		= "gnss-mtk",
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| 		.of_match_table	= of_match_ptr(mtk_of_match),
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| 		.pm		= &gnss_serial_pm_ops,
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| 	},
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| 	.probe	= mtk_probe,
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| 	.remove	= mtk_remove,
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| };
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| module_serdev_device_driver(mtk_driver);
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| 
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| MODULE_AUTHOR("Loys Ollivier <lollivier@baylibre.com>");
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| MODULE_DESCRIPTION("Mediatek GNSS receiver driver");
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| MODULE_LICENSE("GPL v2");
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