diff options
Diffstat (limited to 'drivers/input/misc/mpu3050.c')
| -rw-r--r-- | drivers/input/misc/mpu3050.c | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/drivers/input/misc/mpu3050.c b/drivers/input/misc/mpu3050.c new file mode 100644 index 000000000000..b95fac15b2ea --- /dev/null +++ b/drivers/input/misc/mpu3050.c @@ -0,0 +1,376 @@ +/* + * MPU3050 Tri-axis gyroscope driver + * + * Copyright (C) 2011 Wistron Co.Ltd + * Joseph Lai <joseph_lai@wistron.com> + * + * Trimmed down by Alan Cox <alan@linux.intel.com> to produce this version + * + * This is a 'lite' version of the driver, while we consider the right way + * to present the other features to user space. In particular it requires the + * device has an IRQ, and it only provides an input interface, so is not much + * use for device orientation. A fuller version is available from the Meego + * tree. + * + * This program is based on bma023.c. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * 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., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + * + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/mutex.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/input.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/pm_runtime.h> + +#define MPU3050_CHIP_ID_REG 0x00 +#define MPU3050_CHIP_ID 0x69 +#define MPU3050_XOUT_H 0x1D +#define MPU3050_PWR_MGM 0x3E +#define MPU3050_PWR_MGM_POS 6 +#define MPU3050_PWR_MGM_MASK 0x40 + +#define MPU3050_AUTO_DELAY 1000 + +#define MPU3050_MIN_VALUE -32768 +#define MPU3050_MAX_VALUE 32767 + +struct axis_data { + s16 x; + s16 y; + s16 z; +}; + +struct mpu3050_sensor { + struct i2c_client *client; + struct device *dev; + struct input_dev *idev; +}; + +/** + * mpu3050_xyz_read_reg - read the axes values + * @buffer: provide register addr and get register + * @length: length of register + * + * Reads the register values in one transaction or returns a negative + * error code on failure. + */ +static int mpu3050_xyz_read_reg(struct i2c_client *client, + u8 *buffer, int length) +{ + /* + * Annoying we can't make this const because the i2c layer doesn't + * declare input buffers const. + */ + char cmd = MPU3050_XOUT_H; + struct i2c_msg msg[] = { + { + .addr = client->addr, + .flags = 0, + .len = 1, + .buf = &cmd, + }, + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = length, + .buf = buffer, + }, + }; + + return i2c_transfer(client->adapter, msg, 2); +} + +/** + * mpu3050_read_xyz - get co-ordinates from device + * @client: i2c address of sensor + * @coords: co-ordinates to update + * + * Return the converted X Y and Z co-ordinates from the sensor device + */ +static void mpu3050_read_xyz(struct i2c_client *client, + struct axis_data *coords) +{ + u16 buffer[3]; + + mpu3050_xyz_read_reg(client, (u8 *)buffer, 6); + coords->x = be16_to_cpu(buffer[0]); + coords->y = be16_to_cpu(buffer[1]); + coords->z = be16_to_cpu(buffer[2]); + dev_dbg(&client->dev, "%s: x %d, y %d, z %d\n", __func__, + coords->x, coords->y, coords->z); +} + +/** + * mpu3050_set_power_mode - set the power mode + * @client: i2c client for the sensor + * @val: value to switch on/off of power, 1: normal power, 0: low power + * + * Put device to normal-power mode or low-power mode. + */ +static void mpu3050_set_power_mode(struct i2c_client *client, u8 val) +{ + u8 value; + + value = i2c_smbus_read_byte_data(client, MPU3050_PWR_MGM); + value = (value & ~MPU3050_PWR_MGM_MASK) | + (((val << MPU3050_PWR_MGM_POS) & MPU3050_PWR_MGM_MASK) ^ + MPU3050_PWR_MGM_MASK); + i2c_smbus_write_byte_data(client, MPU3050_PWR_MGM, value); +} + +/** + * mpu3050_input_open - called on input event open + * @input: input dev of opened device + * + * The input layer calls this function when input event is opened. The + * function will push the device to resume. Then, the device is ready + * to provide data. + */ +static int mpu3050_input_open(struct input_dev *input) +{ + struct mpu3050_sensor *sensor = input_get_drvdata(input); + + pm_runtime_get(sensor->dev); + + return 0; +} + +/** + * mpu3050_input_close - called on input event close + * @input: input dev of closed device + * + * The input layer calls this function when input event is closed. The + * function will push the device to suspend. + */ +static void mpu3050_input_close(struct input_dev *input) +{ + struct mpu3050_sensor *sensor = input_get_drvdata(input); + + pm_runtime_put(sensor->dev); +} + +/** + * mpu3050_interrupt_thread - handle an IRQ + * @irq: interrupt numner + * @data: the sensor + * + * Called by the kernel single threaded after an interrupt occurs. Read + * the sensor data and generate an input event for it. + */ +static irqreturn_t mpu3050_interrupt_thread(int irq, void *data) +{ + struct mpu3050_sensor *sensor = data; + struct axis_data axis; + + mpu3050_read_xyz(sensor->client, &axis); + + input_report_abs(sensor->idev, ABS_X, axis.x); + input_report_abs(sensor->idev, ABS_Y, axis.y); + input_report_abs(sensor->idev, ABS_Z, axis.z); + input_sync(sensor->idev); + + return IRQ_HANDLED; +} + +/** + * mpu3050_probe - device detection callback + * @client: i2c client of found device + * @id: id match information + * + * The I2C layer calls us when it believes a sensor is present at this + * address. Probe to see if this is correct and to validate the device. + * + * If present install the relevant sysfs interfaces and input device. + */ +static int __devinit mpu3050_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct mpu3050_sensor *sensor; + struct input_dev *idev; + int ret; + int error; + + sensor = kzalloc(sizeof(struct mpu3050_sensor), GFP_KERNEL); + idev = input_allocate_device(); + if (!sensor || !idev) { + dev_err(&client->dev, "failed to allocate driver data\n"); + error = -ENOMEM; + goto err_free_mem; + } + + sensor->client = client; + sensor->dev = &client->dev; + sensor->idev = idev; + + mpu3050_set_power_mode(client, 1); + msleep(10); + + ret = i2c_smbus_read_byte_data(client, MPU3050_CHIP_ID_REG); + if (ret < 0) { + dev_err(&client->dev, "failed to detect device\n"); + error = -ENXIO; + goto err_free_mem; + } + + if (ret != MPU3050_CHIP_ID) { + dev_err(&client->dev, "unsupported chip id\n"); + error = -ENXIO; + goto err_free_mem; + } + + idev->name = "MPU3050"; + idev->id.bustype = BUS_I2C; + idev->dev.parent = &client->dev; + + idev->open = mpu3050_input_open; + idev->close = mpu3050_input_close; + + __set_bit(EV_ABS, idev->evbit); + input_set_abs_params(idev, ABS_X, + MPU3050_MIN_VALUE, MPU3050_MAX_VALUE, 0, 0); + input_set_abs_params(idev, ABS_Y, + MPU3050_MIN_VALUE, MPU3050_MAX_VALUE, 0, 0); + input_set_abs_params(idev, ABS_Z, + MPU3050_MIN_VALUE, MPU3050_MAX_VALUE, 0, 0); + + input_set_drvdata(idev, sensor); + + pm_runtime_set_active(&client->dev); + + error = request_threaded_irq(client->irq, + NULL, mpu3050_interrupt_thread, + IRQF_TRIGGER_RISING, + "mpu_int", sensor); + if (error) { + dev_err(&client->dev, + "can't get IRQ %d, error %d\n", client->irq, error); + goto err_pm_set_suspended; + } + + error = input_register_device(idev); + if (error) { + dev_err(&client->dev, "failed to register input device\n"); + goto err_free_irq; + } + + pm_runtime_enable(&client->dev); + pm_runtime_set_autosuspend_delay(&client->dev, MPU3050_AUTO_DELAY); + + return 0; + +err_free_irq: + free_irq(client->irq, sensor); +err_pm_set_suspended: + pm_runtime_set_suspended(&client->dev); +err_free_mem: + input_unregister_device(idev); + kfree(sensor); + return error; +} + +/** + * mpu3050_remove - remove a sensor + * @client: i2c client of sensor being removed + * + * Our sensor is going away, clean up the resources. + */ +static int __devexit mpu3050_remove(struct i2c_client *client) +{ + struct mpu3050_sensor *sensor = i2c_get_clientdata(client); + + pm_runtime_disable(&client->dev); + pm_runtime_set_suspended(&client->dev); + + free_irq(client->irq, sensor); + input_unregister_device(sensor->idev); + kfree(sensor); + + return 0; +} + +#ifdef CONFIG_PM +/** + * mpu3050_suspend - called on device suspend + * @dev: device being suspended + * + * Put the device into sleep mode before we suspend the machine. + */ +static int mpu3050_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + + mpu3050_set_power_mode(client, 0); + + return 0; +} + +/** + * mpu3050_resume - called on device resume + * @dev: device being resumed + * + * Put the device into powered mode on resume. + */ +static int mpu3050_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + + mpu3050_set_power_mode(client, 1); + msleep(100); /* wait for gyro chip resume */ + + return 0; +} +#endif + +static UNIVERSAL_DEV_PM_OPS(mpu3050_pm, mpu3050_suspend, mpu3050_resume, NULL); + +static const struct i2c_device_id mpu3050_ids[] = { + { "mpu3050", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, mpu3050_ids); + +static struct i2c_driver mpu3050_i2c_driver = { + .driver = { + .name = "mpu3050", + .owner = THIS_MODULE, + .pm = &mpu3050_pm, + }, + .probe = mpu3050_probe, + .remove = __devexit_p(mpu3050_remove), + .id_table = mpu3050_ids, +}; + +static int __init mpu3050_init(void) +{ + return i2c_add_driver(&mpu3050_i2c_driver); +} +module_init(mpu3050_init); + +static void __exit mpu3050_exit(void) +{ + i2c_del_driver(&mpu3050_i2c_driver); +} +module_exit(mpu3050_exit); + +MODULE_AUTHOR("Wistron Corp."); +MODULE_DESCRIPTION("MPU3050 Tri-axis gyroscope driver"); +MODULE_LICENSE("GPL"); |