Add driver for serial-connected GlobalTop GNSS receivers. These devices typically boot transmitting vendor specific NMEA output sequences. The serial port bit rate is read from the device tree "current-speed".
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 globaltop 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 the timepulse-support is left unimplemented. Signed-off-by: Loys Ollivier <[email protected]> --- drivers/gnss/Kconfig | 13 +++++ drivers/gnss/Makefile | 3 + drivers/gnss/core.c | 1 + drivers/gnss/gtop.c | 152 ++++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 169 insertions(+) create mode 100644 drivers/gnss/gtop.c diff --git a/drivers/gnss/Kconfig b/drivers/gnss/Kconfig index 6abc88514512..c93ad134656b 100644 --- a/drivers/gnss/Kconfig +++ b/drivers/gnss/Kconfig @@ -40,4 +40,17 @@ config GNSS_UBX_SERIAL If unsure, say N. +config GNSS_GTOP_SERIAL + tristate "GlobalTop GNSS receiver support" + depends on SERIAL_DEV_BUS + select GNSS_SERIAL + help + Say Y here if you have a GlobalTop GNSS receiver which uses a serial + interface. + + To compile this driver as a module, choose M here: the module will + be called gnss-gtop. + + If unsure, say N. + endif # GNSS diff --git a/drivers/gnss/Makefile b/drivers/gnss/Makefile index 5cf0ebe0330a..becc45f24b8b 100644 --- a/drivers/gnss/Makefile +++ b/drivers/gnss/Makefile @@ -14,3 +14,6 @@ gnss-sirf-y := sirf.o obj-$(CONFIG_GNSS_UBX_SERIAL) += gnss-ubx.o gnss-ubx-y := ubx.o + +obj-$(CONFIG_GNSS_GTOP_SERIAL) += gnss-gtop.o +gnss-gtop-y := gtop.o diff --git a/drivers/gnss/core.c b/drivers/gnss/core.c index 4291a0dd22aa..0b5cd82b1fb7 100644 --- a/drivers/gnss/core.c +++ b/drivers/gnss/core.c @@ -334,6 +334,7 @@ static const char * const gnss_type_names[GNSS_TYPE_COUNT] = { [GNSS_TYPE_NMEA] = "NMEA", [GNSS_TYPE_SIRF] = "SiRF", [GNSS_TYPE_UBX] = "UBX", + [GNSS_TYPE_GTOP] = "GTOP", }; static const char *gnss_type_name(struct gnss_device *gdev) diff --git a/drivers/gnss/gtop.c b/drivers/gnss/gtop.c new file mode 100644 index 000000000000..6fa7b425d711 --- /dev/null +++ b/drivers/gnss/gtop.c @@ -0,0 +1,152 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * GlobalTop GNSS receiver driver + * + * Copyright (C) 2018 Loys Ollivier <[email protected]> + */ + +#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 gtop_data { + struct regulator *v_bckp; + struct regulator *vcc; +}; + +static int gtop_set_active(struct gnss_serial *gserial) +{ + struct gtop_data *data = gnss_serial_get_drvdata(gserial); + int ret; + + ret = regulator_enable(data->vcc); + if (ret) + return ret; + + return 0; +} + +static int gtop_set_standby(struct gnss_serial *gserial) +{ + struct gtop_data *data = gnss_serial_get_drvdata(gserial); + int ret; + + ret = regulator_disable(data->vcc); + if (ret) + return ret; + + return 0; +} + +static int gtop_set_power(struct gnss_serial *gserial, + enum gnss_serial_pm_state state) +{ + switch (state) { + case GNSS_SERIAL_ACTIVE: + return gtop_set_active(gserial); + case GNSS_SERIAL_OFF: + case GNSS_SERIAL_STANDBY: + return gtop_set_standby(gserial); + } + + return -EINVAL; +} + +static const struct gnss_serial_ops gtop_gserial_ops = { + .set_power = gtop_set_power, +}; + +static int gtop_probe(struct serdev_device *serdev) +{ + struct gnss_serial *gserial; + struct gtop_data *data; + int ret; + + gserial = gnss_serial_allocate(serdev, sizeof(*data)); + if (IS_ERR(gserial)) { + ret = PTR_ERR(gserial); + return ret; + } + + gserial->ops = >op_gserial_ops; + + gserial->gdev->type = GNSS_TYPE_GTOP; + + 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 gtop_remove(struct serdev_device *serdev) +{ + struct gnss_serial *gserial = serdev_device_get_drvdata(serdev); + struct gtop_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 gtop_of_match[] = { + { .compatible = "globaltop,pa6h" }, + {}, +}; +MODULE_DEVICE_TABLE(of, gtop_of_match); +#endif + +static struct serdev_device_driver gtop_driver = { + .driver = { + .name = "gnss-gtop", + .of_match_table = of_match_ptr(gtop_of_match), + .pm = &gnss_serial_pm_ops, + }, + .probe = gtop_probe, + .remove = gtop_remove, +}; +module_serdev_device_driver(gtop_driver); + +MODULE_AUTHOR("Loys Ollivier <[email protected]>"); +MODULE_DESCRIPTION("GlobalTop GNSS receiver driver"); +MODULE_LICENSE("GPL v2"); -- 2.7.4
