Hello,
This is a driver for Broadcom's BCM4751 GPS chip and
this is the first time this driver is sent for review,
all comments are welcome.
Thanks,
Matti A.
Matti J. Aaltonen (1):
MISC: Broadcom BCM4751 GPS driver
drivers/misc/Kconfig | 11 +
drivers/misc/Makefile | 1 +
drivers/misc/bcm4751-gps.c | 490 +++++++++++++++++++++++++++++++++++++++
include/linux/i2c/bcm4751-gps.h | 59 +++++
4 files changed, 561 insertions(+), 0 deletions(-)
create mode 100644 drivers/misc/bcm4751-gps.c
create mode 100644 include/linux/i2c/bcm4751-gps.h
Driver for Broadcom BCM4751 GPS chip.
Signed-off-by: Matti J. Aaltonen <[email protected]>
---
drivers/misc/Kconfig | 11 +
drivers/misc/Makefile | 1 +
drivers/misc/bcm4751-gps.c | 490 +++++++++++++++++++++++++++++++++++++++
include/linux/i2c/bcm4751-gps.h | 59 +++++
4 files changed, 561 insertions(+), 0 deletions(-)
create mode 100644 drivers/misc/bcm4751-gps.c
create mode 100644 include/linux/i2c/bcm4751-gps.h
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 0b591b6..1680673 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -390,6 +390,17 @@ config BMP085
To compile this driver as a module, choose M here: the
module will be called bmp085.
+config BCM4751_GPS
+ tristate "BCM4751 GPS driver"
+ depends on I2C
+ default n
+ ---help---
+ If you say yes here you get support for the Broadcom BCM4751 GPS
+ chip driver.
+
+ The driver supports only GPS in BCM4751 chip. When built as a driver
+ driver name is: bcm4751-gps. If unsure, say N here.
+
source "drivers/misc/c2port/Kconfig"
source "drivers/misc/eeprom/Kconfig"
source "drivers/misc/cb710/Kconfig"
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 255a80d..cfda6fb 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_AD525X_DPOT_SPI) += ad525x_dpot-spi.o
obj-$(CONFIG_ATMEL_PWM) += atmel_pwm.o
obj-$(CONFIG_ATMEL_SSC) += atmel-ssc.o
obj-$(CONFIG_ATMEL_TCLIB) += atmel_tclib.o
+obj-$(CONFIG_BCM4751_GPS) += bcm4751-gps.o
obj-$(CONFIG_BMP085) += bmp085.o
obj-$(CONFIG_ICS932S401) += ics932s401.o
obj-$(CONFIG_LKDTM) += lkdtm.o
diff --git a/drivers/misc/bcm4751-gps.c b/drivers/misc/bcm4751-gps.c
new file mode 100644
index 0000000..03a3752
--- /dev/null
+++ b/drivers/misc/bcm4751-gps.c
@@ -0,0 +1,490 @@
+/*
+ * bcm4751-gps.c - Hardware interface for Broadcom BCM4751 GPS chip.
+ *
+ * Copyright (C) 2010 Nokia Corporation
+ * Contact Matti Aaltonen, [email protected]
+ *
+ * Written by Andrei Emeltchenko <[email protected]>
+ * Modified by Yuri Zaporozhets <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#define DEBUG
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/fs.h>
+#include <linux/gpio.h>
+#include <linux/i2c.h>
+#include <linux/i2c-dev.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/poll.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+#include <linux/i2c/bcm4751-gps.h>
+
+static struct bcm4751_gps_data *bcm4751_gps_device;
+
+static const char reg_vbat[] = "Vbat";
+static const char reg_vddio[] = "Vddio";
+
+/*
+ * Part of initialization is done in the board support file.
+ */
+
+static inline void bcm4751_gps_enable(struct bcm4751_gps_data *self)
+{
+ mutex_lock(&self->mutex);
+ if (!self->enable) {
+ regulator_bulk_enable(ARRAY_SIZE(self->regs), self->regs);
+ if (self->pdata->enable)
+ self->pdata->enable(self->client);
+ self->enable = 1;
+ }
+ mutex_unlock(&self->mutex);
+}
+
+static inline void bcm4751_gps_disable(struct bcm4751_gps_data *self)
+{
+ mutex_lock(&self->mutex);
+ if (self->enable) {
+ if (self->pdata->disable)
+ self->pdata->disable(self->client);
+ self->enable = 0;
+ regulator_bulk_disable(ARRAY_SIZE(self->regs), self->regs);
+ }
+ mutex_unlock(&self->mutex);
+}
+
+static inline void bcm4751_gps_wakeup_value(struct bcm4751_gps_data *self,
+ int value)
+{
+ mutex_lock(&self->mutex);
+ if (self->pdata->wakeup_ctrl)
+ self->pdata->wakeup_ctrl(self->client, value);
+ self->wakeup = value;
+ mutex_unlock(&self->mutex);
+}
+
+
+/*
+ * miscdevice interface
+ */
+
+static int bcm4751_gps_open(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+
+static int bcm4751_gps_release(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+
+static ssize_t bcm4751_gps_read(struct file *file, char __user *buf,
+ size_t count, loff_t *offset)
+{
+ struct i2c_client *client = bcm4751_gps_device->client;
+ int num_read;
+ uint8_t tmp[BCM4751_MAX_BINPKT_RX_LEN];
+
+ /* Adjust for binary packet size */
+ if (count > BCM4751_MAX_BINPKT_RX_LEN)
+ count = BCM4751_MAX_BINPKT_RX_LEN;
+
+ dev_dbg(&client->dev, "reading %d bytes\n", count);
+
+ num_read = i2c_master_recv(client, tmp, count);
+
+ if (num_read < 0) {
+ dev_err(&client->dev, "got %d bytes instead of %d\n",
+ num_read, count);
+ return num_read;
+ } else {
+ dev_dbg(&client->dev, "reading %d bytes returns %d",
+ count, num_read);
+ }
+
+ return copy_to_user(buf, tmp, num_read) ? -EFAULT : num_read;
+}
+
+static ssize_t bcm4751_gps_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *offset)
+{
+ struct i2c_client *client = bcm4751_gps_device->client;
+ uint8_t tmp[BCM4751_MAX_BINPKT_TX_LEN];
+ int num_sent;
+
+ if (count > BCM4751_MAX_BINPKT_TX_LEN)
+ count = BCM4751_MAX_BINPKT_TX_LEN;
+
+ dev_dbg(&client->dev, "writing %d bytes\n", count);
+
+ if (copy_from_user(tmp, buf, count))
+ return -EFAULT;
+
+ num_sent = i2c_master_send(client, tmp, count);
+
+ dev_dbg(&client->dev, "writing %d bytes returns %d",
+ count, num_sent);
+
+ return num_sent;
+}
+
+static int bcm4751_gps_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ struct i2c_client *client = bcm4751_gps_device->client;
+
+ dev_dbg(&client->dev, "ioctl: cmd = 0x%02x, arg=0x%02lx\n", cmd, arg);
+
+ switch (cmd) {
+ case I2C_SLAVE:
+ case I2C_SLAVE_FORCE:
+ if ((arg > 0x3ff) ||
+ (((client->flags & I2C_M_TEN) == 0) &&
+ arg > 0x7f))
+ return -EINVAL;
+ client->addr = arg;
+ dev_dbg(&client->dev, "ioctl: client->addr = %x", client->addr);
+ return 0;
+ case I2C_TENBIT:
+ if (arg)
+ client->flags |= I2C_M_TEN;
+ else
+ client->flags &= ~I2C_M_TEN;
+ return 0;
+ default:
+ return -ENOTTY;
+ }
+ return 0;
+}
+
+static const struct file_operations bcm4751_gps_fileops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .read = bcm4751_gps_read,
+ .write = bcm4751_gps_write,
+ .unlocked_ioctl = bcm4751_gps_ioctl,
+ .open = bcm4751_gps_open,
+ .release = bcm4751_gps_release,
+};
+
+static struct miscdevice bcm4751_gps_miscdevice = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "bcm4751-gps",
+ .fops = &bcm4751_gps_fileops
+};
+
+
+/*
+ * sysfs interface
+ */
+
+static ssize_t bcm4751_gps_show_hostreq(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct bcm4751_gps_data *self = dev_get_drvdata(dev);
+ int value = -1;
+
+ if (self->pdata->show_irq)
+ value = self->pdata->show_irq(self->client);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", value);
+}
+
+static ssize_t bcm4751_gps_show_enable(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct bcm4751_gps_data *self = dev_get_drvdata(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", self->enable);
+}
+
+static ssize_t bcm4751_gps_set_enable(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t len)
+{
+ struct bcm4751_gps_data *self = dev_get_drvdata(dev);
+ int value;
+
+ sscanf(buf, "%d", &value);
+ dev_dbg(dev, "enable: %d", value);
+
+ switch (value) {
+ case 0:
+ bcm4751_gps_disable(self);
+ break;
+
+ case 1:
+ bcm4751_gps_enable(self);
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ return len;
+}
+
+static ssize_t bcm4751_gps_show_wakeup(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct bcm4751_gps_data *self = dev_get_drvdata(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", self->wakeup);
+}
+
+static ssize_t bcm4751_gps_set_wakeup(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t len)
+{
+ unsigned long val;
+ int ret;
+ struct bcm4751_gps_data *self = dev_get_drvdata(dev);
+
+ ret = strict_strtoul(buf, 0, &val);
+ if (ret && val > 1)
+ return -EINVAL;
+ else {
+ bcm4751_gps_wakeup_value(self, val);
+ dev_dbg(dev, "new wakeup value = %d", self->wakeup);
+ }
+
+ return len;
+}
+
+static struct device_attribute bcm4751_gps_attrs[] = {
+ __ATTR(enable, S_IRUGO|S_IWUSR,
+ bcm4751_gps_show_enable, bcm4751_gps_set_enable),
+ __ATTR(hostreq, S_IRUGO|S_IWUSR,
+ bcm4751_gps_show_hostreq, NULL),
+ __ATTR(wakeup, S_IRUGO|S_IWUSR,
+ bcm4751_gps_show_wakeup, bcm4751_gps_set_wakeup),
+};
+
+static int bcm4751_gps_register_sysfs(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ int i, ret;
+
+ for (i = 0; i < ARRAY_SIZE(bcm4751_gps_attrs); i++) {
+ ret = device_create_file(dev, &bcm4751_gps_attrs[i]);
+ if (ret)
+ goto fail;
+ }
+ return 0;
+fail:
+ while (i--)
+ device_remove_file(dev, &bcm4751_gps_attrs[i]);
+
+ return ret;
+}
+
+static void bcm4751_gps_unregister_sysfs(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ int i;
+
+ for (i = ARRAY_SIZE(bcm4751_gps_attrs) - 1; i >= 0; i--)
+ device_remove_file(dev, &bcm4751_gps_attrs[i]);
+}
+
+/* IRQ thread */
+static irqreturn_t bcm4751_gps_irq_thread(int irq, void *dev_id)
+{
+ struct bcm4751_gps_data *data = dev_id;
+
+ dev_dbg(&data->client->dev, "irq, HOST_REQ=%d",
+ data->pdata->show_irq(data->client));
+
+ /* Update sysfs GPIO line here */
+ sysfs_notify(&data->client->dev.kobj, NULL, "hostreq");
+ return IRQ_HANDLED;
+}
+
+static int bcm4751_gps_probe(struct i2c_client *client,
+ const struct i2c_device_id *device_id)
+{
+ struct bcm4751_gps_data *data;
+ struct bcm4751_gps_platform_data *pdata;
+ int err;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ bcm4751_gps_device = data;
+
+ pdata = client->dev.platform_data;
+ if (!pdata) {
+ dev_err(&client->dev, "no platform data\n");
+ err = -ENODEV;
+ goto clean_data;
+ }
+
+ i2c_set_clientdata(client, data);
+ data->client = client;
+ data->pdata = pdata;
+
+ data->gpio_irq = pdata->gps_gpio_irq;
+ data->gpio_enable = pdata->gps_gpio_enable;
+ data->gpio_wakeup = pdata->gps_gpio_wakeup;
+
+ data->regs[0].supply = reg_vbat;
+ data->regs[1].supply = reg_vddio;
+ err = regulator_bulk_get(&client->dev,
+ ARRAY_SIZE(data->regs), data->regs);
+ if (err < 0) {
+ dev_err(&client->dev, "Can't get regulators\n");
+ goto clean_data;
+ }
+
+ if (pdata->setup) {
+ err = pdata->setup(client);
+ if (err)
+ goto clean_reg;
+ }
+
+ mutex_init(&data->mutex);
+ err = request_threaded_irq(client->irq, NULL,
+ bcm4751_gps_irq_thread,
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ "bcm4751-gps", data);
+ if (err) {
+ dev_err(&client->dev, "could not get GPS_IRQ = %d\n",
+ client->irq);
+ goto clean_setup;
+ }
+
+ err = bcm4751_gps_register_sysfs(client);
+ if (err) {
+ dev_err(&client->dev,
+ "sysfs registration failed, error %d\n", err);
+ goto clean_irq;
+ }
+
+ bcm4751_gps_miscdevice.parent = &client->dev;
+ err = misc_register(&bcm4751_gps_miscdevice);
+ if (err) {
+ dev_err(&client->dev, "Miscdevice register failed\n");
+ goto clean_sysfs;
+ }
+
+ return 0;
+
+clean_sysfs:
+ bcm4751_gps_unregister_sysfs(client);
+
+clean_irq:
+ free_irq(client->irq, data);
+
+clean_setup:
+ if (pdata->cleanup)
+ pdata->cleanup(client);
+clean_reg:
+ regulator_bulk_free(ARRAY_SIZE(data->regs), data->regs);
+clean_data:
+ bcm4751_gps_device = NULL;
+ kfree(data);
+
+ return err;
+}
+
+static int bcm4751_gps_remove(struct i2c_client *client)
+{
+ struct bcm4751_gps_data *data = i2c_get_clientdata(client);
+
+ bcm4751_gps_disable(data);
+
+ free_irq(client->irq, data);
+ misc_deregister(&bcm4751_gps_miscdevice);
+ bcm4751_gps_unregister_sysfs(client);
+ if (data->pdata->cleanup)
+ data->pdata->cleanup(client);
+ regulator_bulk_free(ARRAY_SIZE(data->regs), data->regs);
+ kfree(data);
+ bcm4751_gps_device = NULL;
+
+ return 0;
+}
+
+static void bcm4751_gps_shutdown(struct i2c_client *client)
+{
+ dev_dbg(&client->dev, "BCM4751 shutdown\n");
+ bcm4751_gps_disable(i2c_get_clientdata(client));
+}
+
+#ifdef CONFIG_PM
+static int bcm4751_gps_suspend(struct i2c_client *client, pm_message_t mesg)
+{
+ struct bcm4751_gps_data *data = i2c_get_clientdata(client);
+ data->pdata->wakeup_ctrl(data->client, 0);
+ dev_dbg(&client->dev, "BCM4751 suspends\n");
+ return 0;
+}
+
+static int bcm4751_gps_resume(struct i2c_client *client)
+{
+ struct bcm4751_gps_data *data = i2c_get_clientdata(client);
+ data->pdata->wakeup_ctrl(data->client, 1);
+ dev_dbg(&client->dev, "BCM4751 resumes\n");
+ return 0;
+}
+#else
+#define bcm4751_gps_suspend NULL
+#define bcm4751_gps_resume NULL
+#endif
+
+static const struct i2c_device_id bcm4751_gps_id[] = {
+ { "bcm4751-gps", 0 },
+ { },
+};
+
+MODULE_DEVICE_TABLE(i2c, bcm4751_gps_id);
+
+static struct i2c_driver bcm4751_gps_i2c_driver = {
+ .driver = {
+ .name = "bcm4751-gps",
+ },
+
+ .id_table = bcm4751_gps_id,
+ .probe = bcm4751_gps_probe,
+ .remove = __devexit_p(bcm4751_gps_remove),
+ .shutdown = bcm4751_gps_shutdown,
+ .suspend = bcm4751_gps_suspend,
+ .resume = bcm4751_gps_resume,
+};
+
+static int __init bcm4751_gps_init(void)
+{
+ pr_info("Loading BCM4751 GPS driver\n");
+
+ return i2c_add_driver(&bcm4751_gps_i2c_driver);
+}
+module_init(bcm4751_gps_init);
+
+static void __exit bcm4751_gps_exit(void)
+{
+ i2c_del_driver(&bcm4751_gps_i2c_driver);
+}
+module_exit(bcm4751_gps_exit);
+
+MODULE_AUTHOR("Andrei Emeltchenko, Yuri Zaporozhets");
+MODULE_DESCRIPTION("BCM4751 GPS driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/i2c/bcm4751-gps.h b/include/linux/i2c/bcm4751-gps.h
new file mode 100644
index 0000000..69834b9
--- /dev/null
+++ b/include/linux/i2c/bcm4751-gps.h
@@ -0,0 +1,59 @@
+/*
+ * @file include/linux/i2c/bcm4751-gps.h
+ *
+ *
+ * Copyright (C) 2010 Nokia Corporation
+ * Contact Matti Aaltonen, [email protected]
+ *
+ * Written by Andrei Emeltchenko <[email protected]>
+ * Modified by Yuri Zaporozhets <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#ifndef _LINUX_I2C_BCM4751_GPS_H
+#define _LINUX_I2C_BCM4751_GPS_H
+
+/* Max packet sizes for RX and TX */
+#define BCM4751_MAX_BINPKT_RX_LEN 64
+#define BCM4751_MAX_BINPKT_TX_LEN 64
+
+/* Plaform data, used by the board support file */
+struct bcm4751_gps_platform_data {
+ int gps_gpio_irq;
+ int gps_gpio_enable;
+ int gps_gpio_wakeup;
+ int (*setup)(struct i2c_client *client);
+ void (*cleanup)(struct i2c_client *client);
+ void (*enable)(struct i2c_client *client);
+ void (*disable)(struct i2c_client *client);
+ void (*wakeup_ctrl)(struct i2c_client *client, int value);
+ int (*show_irq)(struct i2c_client *client);
+};
+
+/* Used internally by the driver */
+struct bcm4751_gps_data {
+ struct i2c_client *client;
+ struct bcm4751_gps_platform_data *pdata;
+ struct mutex mutex; /* Serialize things */
+ struct regulator_bulk_data regs[2];
+ unsigned int gpio_irq;
+ unsigned int gpio_enable;
+ unsigned int gpio_wakeup;
+ int enable;
+ int wakeup;
+};
+
+#endif
--
1.6.1.3
On Mon 2010-08-23 17:00:26, Matti J. Aaltonen wrote:
> Driver for Broadcom BCM4751 GPS chip.
Uhuh. Tell us more... like what's the interface to userspace? NMEA
data over char device?
Pavel
> Signed-off-by: Matti J. Aaltonen <[email protected]>
> ---
> drivers/misc/Kconfig | 11 +
> drivers/misc/Makefile | 1 +
> drivers/misc/bcm4751-gps.c | 490 +++++++++++++++++++++++++++++++++++++++
> include/linux/i2c/bcm4751-gps.h | 59 +++++
> 4 files changed, 561 insertions(+), 0 deletions(-)
> create mode 100644 drivers/misc/bcm4751-gps.c
> create mode 100644 include/linux/i2c/bcm4751-gps.h
>
> diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
> index 0b591b6..1680673 100644
> --- a/drivers/misc/Kconfig
> +++ b/drivers/misc/Kconfig
> @@ -390,6 +390,17 @@ config BMP085
> To compile this driver as a module, choose M here: the
> module will be called bmp085.
>
> +config BCM4751_GPS
> + tristate "BCM4751 GPS driver"
> + depends on I2C
> + default n
> + ---help---
> + If you say yes here you get support for the Broadcom BCM4751 GPS
> + chip driver.
> +
> + The driver supports only GPS in BCM4751 chip. When built as a driver
> + driver name is: bcm4751-gps. If unsure, say N here.
> +
> source "drivers/misc/c2port/Kconfig"
> source "drivers/misc/eeprom/Kconfig"
> source "drivers/misc/cb710/Kconfig"
> diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
> index 255a80d..cfda6fb 100644
> --- a/drivers/misc/Makefile
> +++ b/drivers/misc/Makefile
> @@ -9,6 +9,7 @@ obj-$(CONFIG_AD525X_DPOT_SPI) += ad525x_dpot-spi.o
> obj-$(CONFIG_ATMEL_PWM) += atmel_pwm.o
> obj-$(CONFIG_ATMEL_SSC) += atmel-ssc.o
> obj-$(CONFIG_ATMEL_TCLIB) += atmel_tclib.o
> +obj-$(CONFIG_BCM4751_GPS) += bcm4751-gps.o
> obj-$(CONFIG_BMP085) += bmp085.o
> obj-$(CONFIG_ICS932S401) += ics932s401.o
> obj-$(CONFIG_LKDTM) += lkdtm.o
> diff --git a/drivers/misc/bcm4751-gps.c b/drivers/misc/bcm4751-gps.c
> new file mode 100644
> index 0000000..03a3752
> --- /dev/null
> +++ b/drivers/misc/bcm4751-gps.c
> @@ -0,0 +1,490 @@
> +/*
> + * bcm4751-gps.c - Hardware interface for Broadcom BCM4751 GPS chip.
> + *
> + * Copyright (C) 2010 Nokia Corporation
> + * Contact Matti Aaltonen, [email protected]
> + *
> + * Written by Andrei Emeltchenko <[email protected]>
> + * Modified by Yuri Zaporozhets <[email protected]>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful, but
> + * WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + * General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
> + * 02110-1301 USA
> + */
> +
> +#define DEBUG
> +
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +#include <linux/fs.h>
> +#include <linux/gpio.h>
> +#include <linux/i2c.h>
> +#include <linux/i2c-dev.h>
> +#include <linux/interrupt.h>
> +#include <linux/kernel.h>
> +#include <linux/miscdevice.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/poll.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/slab.h>
> +
> +#include <linux/i2c/bcm4751-gps.h>
> +
> +static struct bcm4751_gps_data *bcm4751_gps_device;
> +
> +static const char reg_vbat[] = "Vbat";
> +static const char reg_vddio[] = "Vddio";
> +
> +/*
> + * Part of initialization is done in the board support file.
> + */
> +
> +static inline void bcm4751_gps_enable(struct bcm4751_gps_data *self)
> +{
> + mutex_lock(&self->mutex);
> + if (!self->enable) {
> + regulator_bulk_enable(ARRAY_SIZE(self->regs), self->regs);
> + if (self->pdata->enable)
> + self->pdata->enable(self->client);
> + self->enable = 1;
> + }
> + mutex_unlock(&self->mutex);
> +}
> +
> +static inline void bcm4751_gps_disable(struct bcm4751_gps_data *self)
> +{
> + mutex_lock(&self->mutex);
> + if (self->enable) {
> + if (self->pdata->disable)
> + self->pdata->disable(self->client);
> + self->enable = 0;
> + regulator_bulk_disable(ARRAY_SIZE(self->regs), self->regs);
> + }
> + mutex_unlock(&self->mutex);
> +}
> +
> +static inline void bcm4751_gps_wakeup_value(struct bcm4751_gps_data *self,
> + int value)
> +{
> + mutex_lock(&self->mutex);
> + if (self->pdata->wakeup_ctrl)
> + self->pdata->wakeup_ctrl(self->client, value);
> + self->wakeup = value;
> + mutex_unlock(&self->mutex);
> +}
> +
> +
> +/*
> + * miscdevice interface
> + */
> +
> +static int bcm4751_gps_open(struct inode *inode, struct file *file)
> +{
> + return 0;
> +}
> +
> +static int bcm4751_gps_release(struct inode *inode, struct file *file)
> +{
> + return 0;
> +}
> +
> +static ssize_t bcm4751_gps_read(struct file *file, char __user *buf,
> + size_t count, loff_t *offset)
> +{
> + struct i2c_client *client = bcm4751_gps_device->client;
> + int num_read;
> + uint8_t tmp[BCM4751_MAX_BINPKT_RX_LEN];
> +
> + /* Adjust for binary packet size */
> + if (count > BCM4751_MAX_BINPKT_RX_LEN)
> + count = BCM4751_MAX_BINPKT_RX_LEN;
> +
> + dev_dbg(&client->dev, "reading %d bytes\n", count);
> +
> + num_read = i2c_master_recv(client, tmp, count);
> +
> + if (num_read < 0) {
> + dev_err(&client->dev, "got %d bytes instead of %d\n",
> + num_read, count);
> + return num_read;
> + } else {
> + dev_dbg(&client->dev, "reading %d bytes returns %d",
> + count, num_read);
> + }
> +
> + return copy_to_user(buf, tmp, num_read) ? -EFAULT : num_read;
> +}
> +
> +static ssize_t bcm4751_gps_write(struct file *file, const char __user *buf,
> + size_t count, loff_t *offset)
> +{
> + struct i2c_client *client = bcm4751_gps_device->client;
> + uint8_t tmp[BCM4751_MAX_BINPKT_TX_LEN];
> + int num_sent;
> +
> + if (count > BCM4751_MAX_BINPKT_TX_LEN)
> + count = BCM4751_MAX_BINPKT_TX_LEN;
> +
> + dev_dbg(&client->dev, "writing %d bytes\n", count);
> +
> + if (copy_from_user(tmp, buf, count))
> + return -EFAULT;
> +
> + num_sent = i2c_master_send(client, tmp, count);
> +
> + dev_dbg(&client->dev, "writing %d bytes returns %d",
> + count, num_sent);
> +
> + return num_sent;
> +}
> +
> +static int bcm4751_gps_ioctl(struct inode *inode, struct file *file,
> + unsigned int cmd, unsigned long arg)
> +{
> + struct i2c_client *client = bcm4751_gps_device->client;
> +
> + dev_dbg(&client->dev, "ioctl: cmd = 0x%02x, arg=0x%02lx\n", cmd, arg);
> +
> + switch (cmd) {
> + case I2C_SLAVE:
> + case I2C_SLAVE_FORCE:
> + if ((arg > 0x3ff) ||
> + (((client->flags & I2C_M_TEN) == 0) &&
> + arg > 0x7f))
> + return -EINVAL;
> + client->addr = arg;
> + dev_dbg(&client->dev, "ioctl: client->addr = %x", client->addr);
> + return 0;
> + case I2C_TENBIT:
> + if (arg)
> + client->flags |= I2C_M_TEN;
> + else
> + client->flags &= ~I2C_M_TEN;
> + return 0;
> + default:
> + return -ENOTTY;
> + }
> + return 0;
> +}
> +
> +static const struct file_operations bcm4751_gps_fileops = {
> + .owner = THIS_MODULE,
> + .llseek = no_llseek,
> + .read = bcm4751_gps_read,
> + .write = bcm4751_gps_write,
> + .unlocked_ioctl = bcm4751_gps_ioctl,
> + .open = bcm4751_gps_open,
> + .release = bcm4751_gps_release,
> +};
> +
> +static struct miscdevice bcm4751_gps_miscdevice = {
> + .minor = MISC_DYNAMIC_MINOR,
> + .name = "bcm4751-gps",
> + .fops = &bcm4751_gps_fileops
> +};
> +
> +
> +/*
> + * sysfs interface
> + */
> +
> +static ssize_t bcm4751_gps_show_hostreq(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct bcm4751_gps_data *self = dev_get_drvdata(dev);
> + int value = -1;
> +
> + if (self->pdata->show_irq)
> + value = self->pdata->show_irq(self->client);
> +
> + return snprintf(buf, PAGE_SIZE, "%d\n", value);
> +}
> +
> +static ssize_t bcm4751_gps_show_enable(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct bcm4751_gps_data *self = dev_get_drvdata(dev);
> +
> + return snprintf(buf, PAGE_SIZE, "%d\n", self->enable);
> +}
> +
> +static ssize_t bcm4751_gps_set_enable(struct device *dev,
> + struct device_attribute *attr, const char *buf, size_t len)
> +{
> + struct bcm4751_gps_data *self = dev_get_drvdata(dev);
> + int value;
> +
> + sscanf(buf, "%d", &value);
> + dev_dbg(dev, "enable: %d", value);
> +
> + switch (value) {
> + case 0:
> + bcm4751_gps_disable(self);
> + break;
> +
> + case 1:
> + bcm4751_gps_enable(self);
> + break;
> +
> + default:
> + return -EINVAL;
> + }
> + return len;
> +}
> +
> +static ssize_t bcm4751_gps_show_wakeup(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct bcm4751_gps_data *self = dev_get_drvdata(dev);
> +
> + return snprintf(buf, PAGE_SIZE, "%d\n", self->wakeup);
> +}
> +
> +static ssize_t bcm4751_gps_set_wakeup(struct device *dev,
> + struct device_attribute *attr, const char *buf, size_t len)
> +{
> + unsigned long val;
> + int ret;
> + struct bcm4751_gps_data *self = dev_get_drvdata(dev);
> +
> + ret = strict_strtoul(buf, 0, &val);
> + if (ret && val > 1)
> + return -EINVAL;
> + else {
> + bcm4751_gps_wakeup_value(self, val);
> + dev_dbg(dev, "new wakeup value = %d", self->wakeup);
> + }
> +
> + return len;
> +}
> +
> +static struct device_attribute bcm4751_gps_attrs[] = {
> + __ATTR(enable, S_IRUGO|S_IWUSR,
> + bcm4751_gps_show_enable, bcm4751_gps_set_enable),
> + __ATTR(hostreq, S_IRUGO|S_IWUSR,
> + bcm4751_gps_show_hostreq, NULL),
> + __ATTR(wakeup, S_IRUGO|S_IWUSR,
> + bcm4751_gps_show_wakeup, bcm4751_gps_set_wakeup),
> +};
> +
> +static int bcm4751_gps_register_sysfs(struct i2c_client *client)
> +{
> + struct device *dev = &client->dev;
> + int i, ret;
> +
> + for (i = 0; i < ARRAY_SIZE(bcm4751_gps_attrs); i++) {
> + ret = device_create_file(dev, &bcm4751_gps_attrs[i]);
> + if (ret)
> + goto fail;
> + }
> + return 0;
> +fail:
> + while (i--)
> + device_remove_file(dev, &bcm4751_gps_attrs[i]);
> +
> + return ret;
> +}
> +
> +static void bcm4751_gps_unregister_sysfs(struct i2c_client *client)
> +{
> + struct device *dev = &client->dev;
> + int i;
> +
> + for (i = ARRAY_SIZE(bcm4751_gps_attrs) - 1; i >= 0; i--)
> + device_remove_file(dev, &bcm4751_gps_attrs[i]);
> +}
> +
> +/* IRQ thread */
> +static irqreturn_t bcm4751_gps_irq_thread(int irq, void *dev_id)
> +{
> + struct bcm4751_gps_data *data = dev_id;
> +
> + dev_dbg(&data->client->dev, "irq, HOST_REQ=%d",
> + data->pdata->show_irq(data->client));
> +
> + /* Update sysfs GPIO line here */
> + sysfs_notify(&data->client->dev.kobj, NULL, "hostreq");
> + return IRQ_HANDLED;
> +}
> +
> +static int bcm4751_gps_probe(struct i2c_client *client,
> + const struct i2c_device_id *device_id)
> +{
> + struct bcm4751_gps_data *data;
> + struct bcm4751_gps_platform_data *pdata;
> + int err;
> +
> + data = kzalloc(sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + bcm4751_gps_device = data;
> +
> + pdata = client->dev.platform_data;
> + if (!pdata) {
> + dev_err(&client->dev, "no platform data\n");
> + err = -ENODEV;
> + goto clean_data;
> + }
> +
> + i2c_set_clientdata(client, data);
> + data->client = client;
> + data->pdata = pdata;
> +
> + data->gpio_irq = pdata->gps_gpio_irq;
> + data->gpio_enable = pdata->gps_gpio_enable;
> + data->gpio_wakeup = pdata->gps_gpio_wakeup;
> +
> + data->regs[0].supply = reg_vbat;
> + data->regs[1].supply = reg_vddio;
> + err = regulator_bulk_get(&client->dev,
> + ARRAY_SIZE(data->regs), data->regs);
> + if (err < 0) {
> + dev_err(&client->dev, "Can't get regulators\n");
> + goto clean_data;
> + }
> +
> + if (pdata->setup) {
> + err = pdata->setup(client);
> + if (err)
> + goto clean_reg;
> + }
> +
> + mutex_init(&data->mutex);
> + err = request_threaded_irq(client->irq, NULL,
> + bcm4751_gps_irq_thread,
> + IRQF_TRIGGER_RISING | IRQF_ONESHOT,
> + "bcm4751-gps", data);
> + if (err) {
> + dev_err(&client->dev, "could not get GPS_IRQ = %d\n",
> + client->irq);
> + goto clean_setup;
> + }
> +
> + err = bcm4751_gps_register_sysfs(client);
> + if (err) {
> + dev_err(&client->dev,
> + "sysfs registration failed, error %d\n", err);
> + goto clean_irq;
> + }
> +
> + bcm4751_gps_miscdevice.parent = &client->dev;
> + err = misc_register(&bcm4751_gps_miscdevice);
> + if (err) {
> + dev_err(&client->dev, "Miscdevice register failed\n");
> + goto clean_sysfs;
> + }
> +
> + return 0;
> +
> +clean_sysfs:
> + bcm4751_gps_unregister_sysfs(client);
> +
> +clean_irq:
> + free_irq(client->irq, data);
> +
> +clean_setup:
> + if (pdata->cleanup)
> + pdata->cleanup(client);
> +clean_reg:
> + regulator_bulk_free(ARRAY_SIZE(data->regs), data->regs);
> +clean_data:
> + bcm4751_gps_device = NULL;
> + kfree(data);
> +
> + return err;
> +}
> +
> +static int bcm4751_gps_remove(struct i2c_client *client)
> +{
> + struct bcm4751_gps_data *data = i2c_get_clientdata(client);
> +
> + bcm4751_gps_disable(data);
> +
> + free_irq(client->irq, data);
> + misc_deregister(&bcm4751_gps_miscdevice);
> + bcm4751_gps_unregister_sysfs(client);
> + if (data->pdata->cleanup)
> + data->pdata->cleanup(client);
> + regulator_bulk_free(ARRAY_SIZE(data->regs), data->regs);
> + kfree(data);
> + bcm4751_gps_device = NULL;
> +
> + return 0;
> +}
> +
> +static void bcm4751_gps_shutdown(struct i2c_client *client)
> +{
> + dev_dbg(&client->dev, "BCM4751 shutdown\n");
> + bcm4751_gps_disable(i2c_get_clientdata(client));
> +}
> +
> +#ifdef CONFIG_PM
> +static int bcm4751_gps_suspend(struct i2c_client *client, pm_message_t mesg)
> +{
> + struct bcm4751_gps_data *data = i2c_get_clientdata(client);
> + data->pdata->wakeup_ctrl(data->client, 0);
> + dev_dbg(&client->dev, "BCM4751 suspends\n");
> + return 0;
> +}
> +
> +static int bcm4751_gps_resume(struct i2c_client *client)
> +{
> + struct bcm4751_gps_data *data = i2c_get_clientdata(client);
> + data->pdata->wakeup_ctrl(data->client, 1);
> + dev_dbg(&client->dev, "BCM4751 resumes\n");
> + return 0;
> +}
> +#else
> +#define bcm4751_gps_suspend NULL
> +#define bcm4751_gps_resume NULL
> +#endif
> +
> +static const struct i2c_device_id bcm4751_gps_id[] = {
> + { "bcm4751-gps", 0 },
> + { },
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, bcm4751_gps_id);
> +
> +static struct i2c_driver bcm4751_gps_i2c_driver = {
> + .driver = {
> + .name = "bcm4751-gps",
> + },
> +
> + .id_table = bcm4751_gps_id,
> + .probe = bcm4751_gps_probe,
> + .remove = __devexit_p(bcm4751_gps_remove),
> + .shutdown = bcm4751_gps_shutdown,
> + .suspend = bcm4751_gps_suspend,
> + .resume = bcm4751_gps_resume,
> +};
> +
> +static int __init bcm4751_gps_init(void)
> +{
> + pr_info("Loading BCM4751 GPS driver\n");
> +
> + return i2c_add_driver(&bcm4751_gps_i2c_driver);
> +}
> +module_init(bcm4751_gps_init);
> +
> +static void __exit bcm4751_gps_exit(void)
> +{
> + i2c_del_driver(&bcm4751_gps_i2c_driver);
> +}
> +module_exit(bcm4751_gps_exit);
> +
> +MODULE_AUTHOR("Andrei Emeltchenko, Yuri Zaporozhets");
> +MODULE_DESCRIPTION("BCM4751 GPS driver");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/i2c/bcm4751-gps.h b/include/linux/i2c/bcm4751-gps.h
> new file mode 100644
> index 0000000..69834b9
> --- /dev/null
> +++ b/include/linux/i2c/bcm4751-gps.h
> @@ -0,0 +1,59 @@
> +/*
> + * @file include/linux/i2c/bcm4751-gps.h
> + *
> + *
> + * Copyright (C) 2010 Nokia Corporation
> + * Contact Matti Aaltonen, [email protected]
> + *
> + * Written by Andrei Emeltchenko <[email protected]>
> + * Modified by Yuri Zaporozhets <[email protected]>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful, but
> + * WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + * General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
> + * 02110-1301 USA
> + */
> +
> +#ifndef _LINUX_I2C_BCM4751_GPS_H
> +#define _LINUX_I2C_BCM4751_GPS_H
> +
> +/* Max packet sizes for RX and TX */
> +#define BCM4751_MAX_BINPKT_RX_LEN 64
> +#define BCM4751_MAX_BINPKT_TX_LEN 64
> +
> +/* Plaform data, used by the board support file */
> +struct bcm4751_gps_platform_data {
> + int gps_gpio_irq;
> + int gps_gpio_enable;
> + int gps_gpio_wakeup;
> + int (*setup)(struct i2c_client *client);
> + void (*cleanup)(struct i2c_client *client);
> + void (*enable)(struct i2c_client *client);
> + void (*disable)(struct i2c_client *client);
> + void (*wakeup_ctrl)(struct i2c_client *client, int value);
> + int (*show_irq)(struct i2c_client *client);
> +};
> +
> +/* Used internally by the driver */
> +struct bcm4751_gps_data {
> + struct i2c_client *client;
> + struct bcm4751_gps_platform_data *pdata;
> + struct mutex mutex; /* Serialize things */
> + struct regulator_bulk_data regs[2];
> + unsigned int gpio_irq;
> + unsigned int gpio_enable;
> + unsigned int gpio_wakeup;
> + int enable;
> + int wakeup;
> +};
> +
> +#endif
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
Hello.
On Wed, 2010-08-25 at 08:07 +0200, ext Pavel Machek wrote:
> On Mon 2010-08-23 17:00:26, Matti J. Aaltonen wrote:
> > Driver for Broadcom BCM4751 GPS chip.
>
>
> Uhuh. Tell us more... like what's the interface to userspace? NMEA
> data over char device?
> Pavel
The interface to user space is MEIF data over a char device. Something
about MEIF can be found at
http://www.forum.nokia.com/info/sw.nokia.com/id/b265d3aa-8198-4eb0-a0e3-077748ccea40/MEIF_Specification_License.pdf.html
Best Regards,
Matti A.
On Thu 2010-08-26 12:31:15, Matti J. Aaltonen wrote:
> Hello.
>
> On Wed, 2010-08-25 at 08:07 +0200, ext Pavel Machek wrote:
> > On Mon 2010-08-23 17:00:26, Matti J. Aaltonen wrote:
> > > Driver for Broadcom BCM4751 GPS chip.
> >
> >
> > Uhuh. Tell us more... like what's the interface to userspace? NMEA
> > data over char device?
>
> The interface to user space is MEIF data over a char device. Something
> about MEIF can be found at
>
> http://www.forum.nokia.com/info/sw.nokia.com/id/b265d3aa-8198-4eb0-a0e3-077748ccea40/MEIF_Specification_License.pdf.html
>
Umm, that contains some legaleese, but nothing useful...?
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
On Thu, 2010-08-26 at 22:09 +0200, ext Pavel Machek wrote:
> On Thu 2010-08-26 12:31:15, Matti J. Aaltonen wrote:
> > Hello.
> >
> > On Wed, 2010-08-25 at 08:07 +0200, ext Pavel Machek wrote:
> > > On Mon 2010-08-23 17:00:26, Matti J. Aaltonen wrote:
> > > > Driver for Broadcom BCM4751 GPS chip.
> > >
> > >
> > > Uhuh. Tell us more... like what's the interface to userspace? NMEA
> > > data over char device?
> >
> > The interface to user space is MEIF data over a char device. Something
> > about MEIF can be found at
> >
> > http://www.forum.nokia.com/info/sw.nokia.com/id/b265d3aa-8198-4eb0-a0e3-077748ccea40/MEIF_Specification_License.pdf.html
> >
>
> Umm, that contains some legaleese, but nothing useful...?
MEIF is a Nokia proprietary protocol. The link above points to a page,
which describes how you can get hold of the MEIF specification.
Regards,
Matti A.
>
>