/* * MPU3050 Tri-axis gyroscope driver * * Copyright (C) 2011 Wistron Co.Ltd * Joseph Lai * * Trimmed down by Alan Cox 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 #include #include #include #include #include #include #include #include #include #include #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_free_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 const struct of_device_id mpu3050_of_match[] = { { .compatible = "invn,mpu3050", }, { }, }; MODULE_DEVICE_TABLE(of, mpu3050_of_match); static struct i2c_driver mpu3050_i2c_driver = { .driver = { .name = "mpu3050", .owner = THIS_MODULE, .pm = &mpu3050_pm, .of_match_table = mpu3050_of_match, }, .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");