From 1ad69f10e3a58db60210f2869d5afddb40714507 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Fri, 1 Jun 2018 10:22:56 +0200 Subject: gnss: add driver for u-blox receivers Add driver for serial-connected u-blox GNSS receivers. Note that the driver uses the generic GNSS serial implementation and therefore essentially only manages power abstracted into three power states: ACTIVE, STANDBY, and OFF. For u-blox receivers with a main supply and no enable-gpios, this simply means that the main supply is disabled in STANDBY and OFF (the optional backup supply is kept enabled while the driver is bound). Note that timepulse-support is not yet implemented. Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/gnss/ubx.c | 151 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 151 insertions(+) create mode 100644 drivers/gnss/ubx.c (limited to 'drivers/gnss/ubx.c') diff --git a/drivers/gnss/ubx.c b/drivers/gnss/ubx.c new file mode 100644 index 000000000000..ecddfb362a6f --- /dev/null +++ b/drivers/gnss/ubx.c @@ -0,0 +1,151 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * u-blox GNSS receiver driver + * + * Copyright (C) 2018 Johan Hovold + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "serial.h" + +struct ubx_data { + struct regulator *v_bckp; + struct regulator *vcc; +}; + +static int ubx_set_active(struct gnss_serial *gserial) +{ + struct ubx_data *data = gnss_serial_get_drvdata(gserial); + int ret; + + ret = regulator_enable(data->vcc); + if (ret) + return ret; + + return 0; +} + +static int ubx_set_standby(struct gnss_serial *gserial) +{ + struct ubx_data *data = gnss_serial_get_drvdata(gserial); + int ret; + + ret = regulator_disable(data->vcc); + if (ret) + return ret; + + return 0; +} + +static int ubx_set_power(struct gnss_serial *gserial, + enum gnss_serial_pm_state state) +{ + switch (state) { + case GNSS_SERIAL_ACTIVE: + return ubx_set_active(gserial); + case GNSS_SERIAL_OFF: + case GNSS_SERIAL_STANDBY: + return ubx_set_standby(gserial); + } + + return -EINVAL; +} + +const struct gnss_serial_ops ubx_gserial_ops = { + .set_power = ubx_set_power, +}; + +static int ubx_probe(struct serdev_device *serdev) +{ + struct gnss_serial *gserial; + struct ubx_data *data; + int ret; + + gserial = gnss_serial_allocate(serdev, sizeof(*data)); + if (IS_ERR(gserial)) { + ret = PTR_ERR(gserial); + return ret; + } + + gserial->ops = &ubx_gserial_ops; + + 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->v_bckp = devm_regulator_get_optional(&serdev->dev, "v-bckp"); + if (IS_ERR(data->v_bckp)) { + ret = PTR_ERR(data->v_bckp); + if (ret == -ENODEV) + data->v_bckp = NULL; + else + goto err_free_gserial; + } + + if (data->v_bckp) { + ret = regulator_enable(data->v_bckp); + if (ret) + goto err_free_gserial; + } + + ret = gnss_serial_register(gserial); + if (ret) + goto err_disable_v_bckp; + + return 0; + +err_disable_v_bckp: + if (data->v_bckp) + regulator_disable(data->v_bckp); +err_free_gserial: + gnss_serial_free(gserial); + + return ret; +} + +static void ubx_remove(struct serdev_device *serdev) +{ + struct gnss_serial *gserial = serdev_device_get_drvdata(serdev); + struct ubx_data *data = gnss_serial_get_drvdata(gserial); + + gnss_serial_deregister(gserial); + if (data->v_bckp) + regulator_disable(data->v_bckp); + gnss_serial_free(gserial); +}; + +#ifdef CONFIG_OF +static const struct of_device_id ubx_of_match[] = { + { .compatible = "u-blox,neo-8" }, + { .compatible = "u-blox,neo-m8" }, + {}, +}; +MODULE_DEVICE_TABLE(of, ubx_of_match); +#endif + +static struct serdev_device_driver ubx_driver = { + .driver = { + .name = "gnss-ubx", + .of_match_table = of_match_ptr(ubx_of_match), + .pm = &gnss_serial_pm_ops, + }, + .probe = ubx_probe, + .remove = ubx_remove, +}; +module_serdev_device_driver(ubx_driver); + +MODULE_AUTHOR("Johan Hovold "); +MODULE_DESCRIPTION("u-blox GNSS receiver driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3