diff options
Diffstat (limited to 'drivers/gnss')
| -rw-r--r-- | drivers/gnss/Kconfig | 43 | ||||
| -rw-r--r-- | drivers/gnss/Makefile | 16 | ||||
| -rw-r--r-- | drivers/gnss/core.c | 420 | ||||
| -rw-r--r-- | drivers/gnss/serial.c | 275 | ||||
| -rw-r--r-- | drivers/gnss/serial.h | 47 | ||||
| -rw-r--r-- | drivers/gnss/sirf.c | 408 | ||||
| -rw-r--r-- | drivers/gnss/ubx.c | 153 |
7 files changed, 1362 insertions, 0 deletions
diff --git a/drivers/gnss/Kconfig b/drivers/gnss/Kconfig new file mode 100644 index 000000000000..6abc88514512 --- /dev/null +++ b/drivers/gnss/Kconfig @@ -0,0 +1,43 @@ +# +# GNSS receiver configuration +# + +menuconfig GNSS + tristate "GNSS receiver support" + ---help--- + Say Y here if you have a GNSS receiver (e.g. a GPS receiver). + + To compile this driver as a module, choose M here: the module will + be called gnss. + +if GNSS + +config GNSS_SERIAL + tristate + +config GNSS_SIRF_SERIAL + tristate "SiRFstar GNSS receiver support" + depends on SERIAL_DEV_BUS + ---help--- + Say Y here if you have a SiRFstar-based GNSS receiver which uses a + serial interface. + + To compile this driver as a module, choose M here: the module will + be called gnss-sirf. + + If unsure, say N. + +config GNSS_UBX_SERIAL + tristate "u-blox GNSS receiver support" + depends on SERIAL_DEV_BUS + select GNSS_SERIAL + ---help--- + Say Y here if you have a u-blox GNSS receiver which uses a serial + interface. + + To compile this driver as a module, choose M here: the module will + be called gnss-ubx. + + If unsure, say N. + +endif # GNSS diff --git a/drivers/gnss/Makefile b/drivers/gnss/Makefile new file mode 100644 index 000000000000..5cf0ebe0330a --- /dev/null +++ b/drivers/gnss/Makefile @@ -0,0 +1,16 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for the GNSS subsystem. +# + +obj-$(CONFIG_GNSS) += gnss.o +gnss-y := core.o + +obj-$(CONFIG_GNSS_SERIAL) += gnss-serial.o +gnss-serial-y := serial.o + +obj-$(CONFIG_GNSS_SIRF_SERIAL) += gnss-sirf.o +gnss-sirf-y := sirf.o + +obj-$(CONFIG_GNSS_UBX_SERIAL) += gnss-ubx.o +gnss-ubx-y := ubx.o diff --git a/drivers/gnss/core.c b/drivers/gnss/core.c new file mode 100644 index 000000000000..4291a0dd22aa --- /dev/null +++ b/drivers/gnss/core.c @@ -0,0 +1,420 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * GNSS receiver core + * + * Copyright (C) 2018 Johan Hovold <johan@kernel.org> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/cdev.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/gnss.h> +#include <linux/idr.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/poll.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <linux/wait.h> + +#define GNSS_FLAG_HAS_WRITE_RAW BIT(0) + +#define GNSS_MINORS 16 + +static DEFINE_IDA(gnss_minors); +static dev_t gnss_first; + +/* FIFO size must be a power of two */ +#define GNSS_READ_FIFO_SIZE 4096 +#define GNSS_WRITE_BUF_SIZE 1024 + +#define to_gnss_device(d) container_of((d), struct gnss_device, dev) + +static int gnss_open(struct inode *inode, struct file *file) +{ + struct gnss_device *gdev; + int ret = 0; + + gdev = container_of(inode->i_cdev, struct gnss_device, cdev); + + get_device(&gdev->dev); + + nonseekable_open(inode, file); + file->private_data = gdev; + + down_write(&gdev->rwsem); + if (gdev->disconnected) { + ret = -ENODEV; + goto unlock; + } + + if (gdev->count++ == 0) { + ret = gdev->ops->open(gdev); + if (ret) + gdev->count--; + } +unlock: + up_write(&gdev->rwsem); + + if (ret) + put_device(&gdev->dev); + + return ret; +} + +static int gnss_release(struct inode *inode, struct file *file) +{ + struct gnss_device *gdev = file->private_data; + + down_write(&gdev->rwsem); + if (gdev->disconnected) + goto unlock; + + if (--gdev->count == 0) { + gdev->ops->close(gdev); + kfifo_reset(&gdev->read_fifo); + } +unlock: + up_write(&gdev->rwsem); + + put_device(&gdev->dev); + + return 0; +} + +static ssize_t gnss_read(struct file *file, char __user *buf, + size_t count, loff_t *pos) +{ + struct gnss_device *gdev = file->private_data; + unsigned int copied; + int ret; + + mutex_lock(&gdev->read_mutex); + while (kfifo_is_empty(&gdev->read_fifo)) { + mutex_unlock(&gdev->read_mutex); + + if (gdev->disconnected) + return 0; + + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + + ret = wait_event_interruptible(gdev->read_queue, + gdev->disconnected || + !kfifo_is_empty(&gdev->read_fifo)); + if (ret) + return -ERESTARTSYS; + + mutex_lock(&gdev->read_mutex); + } + + ret = kfifo_to_user(&gdev->read_fifo, buf, count, &copied); + if (ret == 0) + ret = copied; + + mutex_unlock(&gdev->read_mutex); + + return ret; +} + +static ssize_t gnss_write(struct file *file, const char __user *buf, + size_t count, loff_t *pos) +{ + struct gnss_device *gdev = file->private_data; + size_t written = 0; + int ret; + + if (gdev->disconnected) + return -EIO; + + if (!count) + return 0; + + if (!(gdev->flags & GNSS_FLAG_HAS_WRITE_RAW)) + return -EIO; + + /* Ignoring O_NONBLOCK, write_raw() is synchronous. */ + + ret = mutex_lock_interruptible(&gdev->write_mutex); + if (ret) + return -ERESTARTSYS; + + for (;;) { + size_t n = count - written; + + if (n > GNSS_WRITE_BUF_SIZE) + n = GNSS_WRITE_BUF_SIZE; + + if (copy_from_user(gdev->write_buf, buf, n)) { + ret = -EFAULT; + goto out_unlock; + } + + /* + * Assumes write_raw can always accept GNSS_WRITE_BUF_SIZE + * bytes. + * + * FIXME: revisit + */ + down_read(&gdev->rwsem); + if (!gdev->disconnected) + ret = gdev->ops->write_raw(gdev, gdev->write_buf, n); + else + ret = -EIO; + up_read(&gdev->rwsem); + + if (ret < 0) + break; + + written += ret; + buf += ret; + + if (written == count) + break; + } + + if (written) + ret = written; +out_unlock: + mutex_unlock(&gdev->write_mutex); + + return ret; +} + +static __poll_t gnss_poll(struct file *file, poll_table *wait) +{ + struct gnss_device *gdev = file->private_data; + __poll_t mask = 0; + + poll_wait(file, &gdev->read_queue, wait); + + if (!kfifo_is_empty(&gdev->read_fifo)) + mask |= EPOLLIN | EPOLLRDNORM; + if (gdev->disconnected) + mask |= EPOLLHUP; + + return mask; +} + +static const struct file_operations gnss_fops = { + .owner = THIS_MODULE, + .open = gnss_open, + .release = gnss_release, + .read = gnss_read, + .write = gnss_write, + .poll = gnss_poll, + .llseek = no_llseek, +}; + +static struct class *gnss_class; + +static void gnss_device_release(struct device *dev) +{ + struct gnss_device *gdev = to_gnss_device(dev); + + kfree(gdev->write_buf); + kfifo_free(&gdev->read_fifo); + ida_simple_remove(&gnss_minors, gdev->id); + kfree(gdev); +} + +struct gnss_device *gnss_allocate_device(struct device *parent) +{ + struct gnss_device *gdev; + struct device *dev; + int id; + int ret; + + gdev = kzalloc(sizeof(*gdev), GFP_KERNEL); + if (!gdev) + return NULL; + + id = ida_simple_get(&gnss_minors, 0, GNSS_MINORS, GFP_KERNEL); + if (id < 0) { + kfree(gdev); + return NULL; + } + + gdev->id = id; + + dev = &gdev->dev; + device_initialize(dev); + dev->devt = gnss_first + id; + dev->class = gnss_class; + dev->parent = parent; + dev->release = gnss_device_release; + dev_set_drvdata(dev, gdev); + dev_set_name(dev, "gnss%d", id); + + init_rwsem(&gdev->rwsem); + mutex_init(&gdev->read_mutex); + mutex_init(&gdev->write_mutex); + init_waitqueue_head(&gdev->read_queue); + + ret = kfifo_alloc(&gdev->read_fifo, GNSS_READ_FIFO_SIZE, GFP_KERNEL); + if (ret) + goto err_put_device; + + gdev->write_buf = kzalloc(GNSS_WRITE_BUF_SIZE, GFP_KERNEL); + if (!gdev->write_buf) + goto err_put_device; + + cdev_init(&gdev->cdev, &gnss_fops); + gdev->cdev.owner = THIS_MODULE; + + return gdev; + +err_put_device: + put_device(dev); + + return NULL; +} +EXPORT_SYMBOL_GPL(gnss_allocate_device); + +void gnss_put_device(struct gnss_device *gdev) +{ + put_device(&gdev->dev); +} +EXPORT_SYMBOL_GPL(gnss_put_device); + +int gnss_register_device(struct gnss_device *gdev) +{ + int ret; + + /* Set a flag which can be accessed without holding the rwsem. */ + if (gdev->ops->write_raw != NULL) + gdev->flags |= GNSS_FLAG_HAS_WRITE_RAW; + + ret = cdev_device_add(&gdev->cdev, &gdev->dev); + if (ret) { + dev_err(&gdev->dev, "failed to add device: %d\n", ret); + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(gnss_register_device); + +void gnss_deregister_device(struct gnss_device *gdev) +{ + down_write(&gdev->rwsem); + gdev->disconnected = true; + if (gdev->count) { + wake_up_interruptible(&gdev->read_queue); + gdev->ops->close(gdev); + } + up_write(&gdev->rwsem); + + cdev_device_del(&gdev->cdev, &gdev->dev); +} +EXPORT_SYMBOL_GPL(gnss_deregister_device); + +/* + * Caller guarantees serialisation. + * + * Must not be called for a closed device. + */ +int gnss_insert_raw(struct gnss_device *gdev, const unsigned char *buf, + size_t count) +{ + int ret; + + ret = kfifo_in(&gdev->read_fifo, buf, count); + + wake_up_interruptible(&gdev->read_queue); + + return ret; +} +EXPORT_SYMBOL_GPL(gnss_insert_raw); + +static const char * const gnss_type_names[GNSS_TYPE_COUNT] = { + [GNSS_TYPE_NMEA] = "NMEA", + [GNSS_TYPE_SIRF] = "SiRF", + [GNSS_TYPE_UBX] = "UBX", +}; + +static const char *gnss_type_name(struct gnss_device *gdev) +{ + const char *name = NULL; + + if (gdev->type < GNSS_TYPE_COUNT) + name = gnss_type_names[gdev->type]; + + if (!name) + dev_WARN(&gdev->dev, "type name not defined\n"); + + return name; +} + +static ssize_t type_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct gnss_device *gdev = to_gnss_device(dev); + + return sprintf(buf, "%s\n", gnss_type_name(gdev)); +} +static DEVICE_ATTR_RO(type); + +static struct attribute *gnss_attrs[] = { + &dev_attr_type.attr, + NULL, +}; +ATTRIBUTE_GROUPS(gnss); + +static int gnss_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct gnss_device *gdev = to_gnss_device(dev); + int ret; + + ret = add_uevent_var(env, "GNSS_TYPE=%s", gnss_type_name(gdev)); + if (ret) + return ret; + + return 0; +} + +static int __init gnss_module_init(void) +{ + int ret; + + ret = alloc_chrdev_region(&gnss_first, 0, GNSS_MINORS, "gnss"); + if (ret < 0) { + pr_err("failed to allocate device numbers: %d\n", ret); + return ret; + } + + gnss_class = class_create(THIS_MODULE, "gnss"); + if (IS_ERR(gnss_class)) { + ret = PTR_ERR(gnss_class); + pr_err("failed to create class: %d\n", ret); + goto err_unregister_chrdev; + } + + gnss_class->dev_groups = gnss_groups; + gnss_class->dev_uevent = gnss_uevent; + + pr_info("GNSS driver registered with major %d\n", MAJOR(gnss_first)); + + return 0; + +err_unregister_chrdev: + unregister_chrdev_region(gnss_first, GNSS_MINORS); + + return ret; +} +module_init(gnss_module_init); + +static void __exit gnss_module_exit(void) +{ + class_destroy(gnss_class); + unregister_chrdev_region(gnss_first, GNSS_MINORS); + ida_destroy(&gnss_minors); +} +module_exit(gnss_module_exit); + +MODULE_AUTHOR("Johan Hovold <johan@kernel.org>"); +MODULE_DESCRIPTION("GNSS receiver core"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/gnss/serial.c b/drivers/gnss/serial.c new file mode 100644 index 000000000000..b01ba4438501 --- /dev/null +++ b/drivers/gnss/serial.c @@ -0,0 +1,275 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Generic serial 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/pm.h> +#include <linux/pm_runtime.h> +#include <linux/serdev.h> +#include <linux/slab.h> + +#include "serial.h" + +static int gnss_serial_open(struct gnss_device *gdev) +{ + struct gnss_serial *gserial = gnss_get_drvdata(gdev); + struct serdev_device *serdev = gserial->serdev; + int ret; + + ret = serdev_device_open(serdev); + if (ret) + return ret; + + serdev_device_set_baudrate(serdev, gserial->speed); + serdev_device_set_flow_control(serdev, false); + + ret = pm_runtime_get_sync(&serdev->dev); + if (ret < 0) { + pm_runtime_put_noidle(&serdev->dev); + goto err_close; + } + + return 0; + +err_close: + serdev_device_close(serdev); + + return ret; +} + +static void gnss_serial_close(struct gnss_device *gdev) +{ + struct gnss_serial *gserial = gnss_get_drvdata(gdev); + struct serdev_device *serdev = gserial->serdev; + + serdev_device_close(serdev); + + pm_runtime_put(&serdev->dev); +} + +static int gnss_serial_write_raw(struct gnss_device *gdev, + const unsigned char *buf, size_t count) +{ + struct gnss_serial *gserial = gnss_get_drvdata(gdev); + struct serdev_device *serdev = gserial->serdev; + int ret; + + /* write is only buffered synchronously */ + ret = serdev_device_write(serdev, buf, count, 0); + if (ret < 0) + return ret; + + /* FIXME: determine if interrupted? */ + serdev_device_wait_until_sent(serdev, 0); + + return count; +} + +static const struct gnss_operations gnss_serial_gnss_ops = { + .open = gnss_serial_open, + .close = gnss_serial_close, + .write_raw = gnss_serial_write_raw, +}; + +static int gnss_serial_receive_buf(struct serdev_device *serdev, + const unsigned char *buf, size_t count) +{ + struct gnss_serial *gserial = serdev_device_get_drvdata(serdev); + struct gnss_device *gdev = gserial->gdev; + + return gnss_insert_raw(gdev, buf, count); +} + +static const struct serdev_device_ops gnss_serial_serdev_ops = { + .receive_buf = gnss_serial_receive_buf, + .write_wakeup = serdev_device_write_wakeup, +}; + +static int gnss_serial_set_power(struct gnss_serial *gserial, + enum gnss_serial_pm_state state) +{ + if (!gserial->ops || !gserial->ops->set_power) + return 0; + + return gserial->ops->set_power(gserial, state); +} + +/* + * FIXME: need to provide subdriver defaults or separate dt parsing from + * allocation. + */ +static int gnss_serial_parse_dt(struct serdev_device *serdev) +{ + struct gnss_serial *gserial = serdev_device_get_drvdata(serdev); + struct device_node *node = serdev->dev.of_node; + u32 speed = 4800; + + of_property_read_u32(node, "current-speed", &speed); + + gserial->speed = speed; + + return 0; +} + +struct gnss_serial *gnss_serial_allocate(struct serdev_device *serdev, + size_t data_size) +{ + struct gnss_serial *gserial; + struct gnss_device *gdev; + int ret; + + gserial = kzalloc(sizeof(*gserial) + data_size, GFP_KERNEL); + if (!gserial) + return ERR_PTR(-ENOMEM); + + gdev = gnss_allocate_device(&serdev->dev); + if (!gdev) { + ret = -ENOMEM; + goto err_free_gserial; + } + + gdev->ops = &gnss_serial_gnss_ops; + gnss_set_drvdata(gdev, gserial); + + gserial->serdev = serdev; + gserial->gdev = gdev; + + serdev_device_set_drvdata(serdev, gserial); + serdev_device_set_client_ops(serdev, &gnss_serial_serdev_ops); + + ret = gnss_serial_parse_dt(serdev); + if (ret) + goto err_put_device; + + return gserial; + +err_put_device: + gnss_put_device(gserial->gdev); +err_free_gserial: + kfree(gserial); + + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(gnss_serial_allocate); + +void gnss_serial_free(struct gnss_serial *gserial) +{ + gnss_put_device(gserial->gdev); + kfree(gserial); +}; +EXPORT_SYMBOL_GPL(gnss_serial_free); + +int gnss_serial_register(struct gnss_serial *gserial) +{ + struct serdev_device *serdev = gserial->serdev; + int ret; + + if (IS_ENABLED(CONFIG_PM)) { + pm_runtime_enable(&serdev->dev); + } else { + ret = gnss_serial_set_power(gserial, GNSS_SERIAL_ACTIVE); + if (ret < 0) + return ret; + } + + ret = gnss_register_device(gserial->gdev); + if (ret) + goto err_disable_rpm; + + return 0; + +err_disable_rpm: + if (IS_ENABLED(CONFIG_PM)) + pm_runtime_disable(&serdev->dev); + else + gnss_serial_set_power(gserial, GNSS_SERIAL_OFF); + + return ret; +} +EXPORT_SYMBOL_GPL(gnss_serial_register); + +void gnss_serial_deregister(struct gnss_serial *gserial) +{ + struct serdev_device *serdev = gserial->serdev; + + gnss_deregister_device(gserial->gdev); + + if (IS_ENABLED(CONFIG_PM)) + pm_runtime_disable(&serdev->dev); + else + gnss_serial_set_power(gserial, GNSS_SERIAL_OFF); +} +EXPORT_SYMBOL_GPL(gnss_serial_deregister); + +#ifdef CONFIG_PM +static int gnss_serial_runtime_suspend(struct device *dev) +{ + struct gnss_serial *gserial = dev_get_drvdata(dev); + + return gnss_serial_set_power(gserial, GNSS_SERIAL_STANDBY); +} + +static int gnss_serial_runtime_resume(struct device *dev) +{ + struct gnss_serial *gserial = dev_get_drvdata(dev); + + return gnss_serial_set_power(gserial, GNSS_SERIAL_ACTIVE); +} +#endif /* CONFIG_PM */ + +static int gnss_serial_prepare(struct device *dev) +{ + if (pm_runtime_suspended(dev)) + return 1; + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int gnss_serial_suspend(struct device *dev) +{ + struct gnss_serial *gserial = dev_get_drvdata(dev); + int ret = 0; + + /* + * FIXME: serdev currently lacks support for managing the underlying + * device's wakeup settings. A workaround would be to close the serdev + * device here if it is open. + */ + + if (!pm_runtime_suspended(dev)) + ret = gnss_serial_set_power(gserial, GNSS_SERIAL_STANDBY); + + return ret; +} + +static int gnss_serial_resume(struct device *dev) +{ + struct gnss_serial *gserial = dev_get_drvdata(dev); + int ret = 0; + + if (!pm_runtime_suspended(dev)) + ret = gnss_serial_set_power(gserial, GNSS_SERIAL_ACTIVE); + + return ret; +} +#endif /* CONFIG_PM_SLEEP */ + +const struct dev_pm_ops gnss_serial_pm_ops = { + .prepare = gnss_serial_prepare, + SET_SYSTEM_SLEEP_PM_OPS(gnss_serial_suspend, gnss_serial_resume) + SET_RUNTIME_PM_OPS(gnss_serial_runtime_suspend, gnss_serial_runtime_resume, NULL) +}; +EXPORT_SYMBOL_GPL(gnss_serial_pm_ops); + +MODULE_AUTHOR("Johan Hovold <johan@kernel.org>"); +MODULE_DESCRIPTION("Generic serial GNSS receiver driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/gnss/serial.h b/drivers/gnss/serial.h new file mode 100644 index 000000000000..980ffdc86c2a --- /dev/null +++ b/drivers/gnss/serial.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Generic serial GNSS receiver driver + * + * Copyright (C) 2018 Johan Hovold <johan@kernel.org> + */ + +#ifndef _LINUX_GNSS_SERIAL_H +#define _LINUX_GNSS_SERIAL_H + +#include <asm/termbits.h> +#include <linux/pm.h> + +struct gnss_serial { + struct serdev_device *serdev; + struct gnss_device *gdev; + speed_t speed; + const struct gnss_serial_ops *ops; + unsigned long drvdata[0]; +}; + +enum gnss_serial_pm_state { + GNSS_SERIAL_OFF, + GNSS_SERIAL_ACTIVE, + GNSS_SERIAL_STANDBY, +}; + +struct gnss_serial_ops { + int (*set_power)(struct gnss_serial *gserial, + enum gnss_serial_pm_state state); +}; + +extern const struct dev_pm_ops gnss_serial_pm_ops; + +struct gnss_serial *gnss_serial_allocate(struct serdev_device *gserial, + size_t data_size); +void gnss_serial_free(struct gnss_serial *gserial); + +int gnss_serial_register(struct gnss_serial *gserial); +void gnss_serial_deregister(struct gnss_serial *gserial); + +static inline void *gnss_serial_get_drvdata(struct gnss_serial *gserial) +{ + return gserial->drvdata; +} + +#endif /* _LINUX_GNSS_SERIAL_H */ diff --git a/drivers/gnss/sirf.c b/drivers/gnss/sirf.c new file mode 100644 index 000000000000..79cb98950013 --- /dev/null +++ b/drivers/gnss/sirf.c @@ -0,0 +1,408 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * SiRFstar GNSS receiver driver + * + * Copyright (C) 2018 Johan Hovold <johan@kernel.org> + */ + +#include <linux/errno.h> +#include <linux/gnss.h> +#include <linux/gpio/consumer.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> +#include <linux/regulator/consumer.h> +#include <linux/serdev.h> +#include <linux/slab.h> +#include <linux/wait.h> + +#define SIRF_BOOT_DELAY 500 +#define SIRF_ON_OFF_PULSE_TIME 100 +#define SIRF_ACTIVATE_TIMEOUT 200 +#define SIRF_HIBERNATE_TIMEOUT 200 + +struct sirf_data { + struct gnss_device *gdev; + struct serdev_device *serdev; + speed_t speed; + struct regulator *vcc; + struct gpio_desc *on_off; + struct gpio_desc *wakeup; + int irq; + bool active; + wait_queue_head_t power_wait; +}; + +static int sirf_open(struct gnss_device *gdev) +{ + struct sirf_data *data = gnss_get_drvdata(gdev); + struct serdev_device *serdev = data->serdev; + int ret; + + ret = serdev_device_open(serdev); + if (ret) + return ret; + + serdev_device_set_baudrate(serdev, data->speed); + serdev_device_set_flow_control(serdev, false); + + ret = pm_runtime_get_sync(&serdev->dev); + if (ret < 0) { + dev_err(&gdev->dev, "failed to runtime resume: %d\n", ret); + pm_runtime_put_noidle(&serdev->dev); + goto err_close; + } + + return 0; + +err_close: + serdev_device_close(serdev); + + return ret; +} + +static void sirf_close(struct gnss_device *gdev) +{ + struct sirf_data *data = gnss_get_drvdata(gdev); + struct serdev_device *serdev = data->serdev; + + serdev_device_close(serdev); + + pm_runtime_put(&serdev->dev); +} + +static int sirf_write_raw(struct gnss_device *gdev, const unsigned char *buf, + size_t count) +{ + struct sirf_data *data = gnss_get_drvdata(gdev); + struct serdev_device *serdev = data->serdev; + int ret; + + /* write is only buffered synchronously */ + ret = serdev_device_write(serdev, buf, count, 0); + if (ret < 0) + return ret; + + /* FIXME: determine if interrupted? */ + serdev_device_wait_until_sent(serdev, 0); + + return count; +} + +static const struct gnss_operations sirf_gnss_ops = { + .open = sirf_open, + .close = sirf_close, + .write_raw = sirf_write_raw, +}; + +static int sirf_receive_buf(struct serdev_device *serdev, + const unsigned char *buf, size_t count) +{ + struct sirf_data *data = serdev_device_get_drvdata(serdev); + struct gnss_device *gdev = data->gdev; + + return gnss_insert_raw(gdev, buf, count); +} + +static const struct serdev_device_ops sirf_serdev_ops = { + .receive_buf = sirf_receive_buf, + .write_wakeup = serdev_device_write_wakeup, +}; + +static irqreturn_t sirf_wakeup_handler(int irq, void *dev_id) +{ + struct sirf_data *data = dev_id; + struct device *dev = &data->serdev->dev; + int ret; + + ret = gpiod_get_value_cansleep(data->wakeup); + dev_dbg(dev, "%s - wakeup = %d\n", __func__, ret); + if (ret < 0) + goto out; + + data->active = !!ret; + wake_up_interruptible(&data->power_wait); +out: + return IRQ_HANDLED; +} + +static int sirf_wait_for_power_state(struct sirf_data *data, bool active, + unsigned long timeout) +{ + int ret; + + ret = wait_event_interruptible_timeout(data->power_wait, + data->active == active, msecs_to_jiffies(timeout)); + if (ret < 0) + return ret; + + if (ret == 0) { + dev_warn(&data->serdev->dev, "timeout waiting for active state = %d\n", + active); + return -ETIMEDOUT; + } + + return 0; +} + +static void sirf_pulse_on_off(struct sirf_data *data) +{ + gpiod_set_value_cansleep(data->on_off, 1); + msleep(SIRF_ON_OFF_PULSE_TIME); + gpiod_set_value_cansleep(data->on_off, 0); +} + +static int sirf_set_active(struct sirf_data *data, bool active) +{ + unsigned long timeout; + int retries = 3; + int ret; + + if (active) + timeout = SIRF_ACTIVATE_TIMEOUT; + else + timeout = SIRF_HIBERNATE_TIMEOUT; + + while (retries-- > 0) { + sirf_pulse_on_off(data); + ret = sirf_wait_for_power_state(data, active, timeout); + if (ret < 0) { + if (ret == -ETIMEDOUT) + continue; + + return ret; + } + + break; + } + + if (retries == 0) + return -ETIMEDOUT; + + return 0; +} + +static int sirf_runtime_suspend(struct device *dev) +{ + struct sirf_data *data = dev_get_drvdata(dev); + + if (!data->on_off) + return regulator_disable(data->vcc); + + return sirf_set_active(data, false); +} + +static int sirf_runtime_resume(struct device *dev) +{ + struct sirf_data *data = dev_get_drvdata(dev); + + if (!data->on_off) + return regulator_enable(data->vcc); + + return sirf_set_active(data, true); +} + +static int __maybe_unused sirf_suspend(struct device *dev) +{ + struct sirf_data *data = dev_get_drvdata(dev); + int ret = 0; + + if (!pm_runtime_suspended(dev)) + ret = sirf_runtime_suspend(dev); + + if (data->wakeup) + disable_irq(data->irq); + + return ret; +} + +static int __maybe_unused sirf_resume(struct device *dev) +{ + struct sirf_data *data = dev_get_drvdata(dev); + int ret = 0; + + if (data->wakeup) + enable_irq(data->irq); + + if (!pm_runtime_suspended(dev)) + ret = sirf_runtime_resume(dev); + + return ret; +} + +static const struct dev_pm_ops sirf_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(sirf_suspend, sirf_resume) + SET_RUNTIME_PM_OPS(sirf_runtime_suspend, sirf_runtime_resume, NULL) +}; + +static int sirf_parse_dt(struct serdev_device *serdev) +{ + struct sirf_data *data = serdev_device_get_drvdata(serdev); + struct device_node *node = serdev->dev.of_node; + u32 speed = 9600; + + of_property_read_u32(node, "current-speed", &speed); + + data->speed = speed; + + return 0; +} + +static int sirf_probe(struct serdev_device *serdev) +{ + struct device *dev = &serdev->dev; + struct gnss_device *gdev; + struct sirf_data *data; + int ret; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + gdev = gnss_allocate_device(dev); + if (!gdev) + return -ENOMEM; + + gdev->type = GNSS_TYPE_SIRF; + gdev->ops = &sirf_gnss_ops; + gnss_set_drvdata(gdev, data); + + data->serdev = serdev; + data->gdev = gdev; + + init_waitqueue_head(&data->power_wait); + + serdev_device_set_drvdata(serdev, data); + serdev_device_set_client_ops(serdev, &sirf_serdev_ops); + + ret = sirf_parse_dt(serdev); + if (ret) + goto err_put_device; + + data->vcc = devm_regulator_get(dev, "vcc"); + if (IS_ERR(data->vcc)) { + ret = PTR_ERR(data->vcc); + goto err_put_device; + } + + data->on_off = devm_gpiod_get_optional(dev, "sirf,onoff", + GPIOD_OUT_LOW); + if (IS_ERR(data->on_off)) + goto err_put_device; + + if (data->on_off) { + data->wakeup = devm_gpiod_get_optional(dev, "sirf,wakeup", + GPIOD_IN); + if (IS_ERR(data->wakeup)) + goto err_put_device; + + /* + * Configurations where WAKEUP has been left not connected, + * are currently not supported. + */ + if (!data->wakeup) { + dev_err(dev, "no wakeup gpio specified\n"); + ret = -ENODEV; + goto err_put_device; + } + } + + if (data->wakeup) { + ret = gpiod_to_irq(data->wakeup); + if (ret < 0) + goto err_put_device; + + data->irq = ret; + + ret = devm_request_threaded_irq(dev, data->irq, NULL, + sirf_wakeup_handler, + IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT, + "wakeup", data); + if (ret) + goto err_put_device; + } + + if (data->on_off) { + ret = regulator_enable(data->vcc); + if (ret) + goto err_put_device; + + /* Wait for chip to boot into hibernate mode */ + msleep(SIRF_BOOT_DELAY); + } + + if (IS_ENABLED(CONFIG_PM)) { + pm_runtime_set_suspended(dev); /* clear runtime_error flag */ + pm_runtime_enable(dev); + } else { + ret = sirf_runtime_resume(dev); + if (ret < 0) + goto err_disable_vcc; + } + + ret = gnss_register_device(gdev); + if (ret) + goto err_disable_rpm; + + return 0; + +err_disable_rpm: + if (IS_ENABLED(CONFIG_PM)) + pm_runtime_disable(dev); + else + sirf_runtime_suspend(dev); +err_disable_vcc: + if (data->on_off) + regulator_disable(data->vcc); +err_put_device: + gnss_put_device(data->gdev); + + return ret; +} + +static void sirf_remove(struct serdev_device *serdev) +{ + struct sirf_data *data = serdev_device_get_drvdata(serdev); + + gnss_deregister_device(data->gdev); + + if (IS_ENABLED(CONFIG_PM)) + pm_runtime_disable(&serdev->dev); + else + sirf_runtime_suspend(&serdev->dev); + + if (data->on_off) + regulator_disable(data->vcc); + + gnss_put_device(data->gdev); +}; + +#ifdef CONFIG_OF +static const struct of_device_id sirf_of_match[] = { + { .compatible = "fastrax,uc430" }, + { .compatible = "linx,r4" }, + { .compatible = "wi2wi,w2sg0008i" }, + { .compatible = "wi2wi,w2sg0084i" }, + {}, +}; +MODULE_DEVICE_TABLE(of, sirf_of_match); +#endif + +static struct serdev_device_driver sirf_driver = { + .driver = { + .name = "gnss-sirf", + .of_match_table = of_match_ptr(sirf_of_match), + .pm = &sirf_pm_ops, + }, + .probe = sirf_probe, + .remove = sirf_remove, +}; +module_serdev_device_driver(sirf_driver); + +MODULE_AUTHOR("Johan Hovold <johan@kernel.org>"); +MODULE_DESCRIPTION("SiRFstar GNSS receiver driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/gnss/ubx.c b/drivers/gnss/ubx.c new file mode 100644 index 000000000000..12568aebb7f6 --- /dev/null +++ b/drivers/gnss/ubx.c @@ -0,0 +1,153 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * u-blox 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 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; +} + +static 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; + + gserial->gdev->type = GNSS_TYPE_UBX; + + 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 <johan@kernel.org>"); +MODULE_DESCRIPTION("u-blox GNSS receiver driver"); +MODULE_LICENSE("GPL v2"); |
