| /* |
| * 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"); |