/*
 * mpu6050.c
 *
 *  Created on: 2018年6月25日
 *      Author: anqi
 */


#include "mpu6050.h"
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/cdev.h>
#include <linux/device.h>

MODULE_LICENSE("Dual BSD/GPL")

#define DEV_CNT 1
#define DEV_MI 0
#define DEV_NAME "mpu6050"

dev_t dev_no;
struct class *cls;

struct mpu6050_pri mpu_dev;
static void mpu6050_write_byte(struct i2c_client *client,const unsigned char reg,const unsigned char val)
{
	char txbuf[2] = {reg,val};
	struct i2c_msg msg[2] =
	{
		[0] = {
			.addr = client->addr,
			.flags = W_FLG,
			.len = sizeof(txbuf),
			.buf = txbuf,
		},
	};
	i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
}
static char mpu6050_read_byte(struct i2c_client *client,const unsigned char reg)
{
	char txbuf[1] = {reg};
	char rxbuf[1] = {0};

	struct i2c_msg msg[2] =
	{
		[0] = {
			.addr = client->addr,
			.flags = W_FLG,
			.len = sizeof(txbuf),
			.buf = txbuf,
		},
		[1] = {
			.addr = client->addr,
			.flags = R_FLG,
			.len = sizeof(txbuf),
			.buf = txbuf,
		},

	};
	i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
	return rxbuf[0];
}
static long dev_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
{
	int res;
	union mpu6050_data data = {0};

	switch(cmd)
	{
	case GET_ACCEL:
		data.accel.x = mpu6050_read_byte(mpu_dev.client, ACCEL_XOUT_L);
		data.accel.x |= mpu6050_read_byte(mpu_dev.client, ACCEL_XOUT_H) << 8;

		data.accel.y = mpu6050_read_byte(mpu_dev.client, ACCEL_YOUT_L);
		data.accel.y |= mpu6050_read_byte(mpu_dev.client, ACCEL_YOUT_H) << 8;

		data.accel.z = mpu6050_read_byte(mpu_dev.client, ACCEL_ZOUT_L);
		data.accel.z |= mpu6050_read_byte(mpu_dev.client, ACCEL_ZOUT_H) << 8;

		break;
	case GET_GYRO:
		data.gyro.x = mpu6050_read_byte(mpu_dev.client, GYRO_XOUT_L);
		data.gyro.x |= mpu6050_read_byte(mpu_dev.client, GYRO_XOUT_H) << 8;

		data.gyro.y = mpu6050_read_byte(mpu_dev.client, GYRO_YOUT_L);
		data.gyro.y |= mpu6050_read_byte(mpu_dev.client, GYRO_YOUT_H) << 8;

		data.gyro.z = mpu6050_read_byte(mpu_dev.client, GYRO_ZOUT_L);
		data.gyro.z |= mpu6050_read_byte(mpu_dev.client, GYRO_ZOUT_H) << 8;

		break;
	case GET_TEMP:
		data.temp = mpu6050_read_byte(mpu_dev.client, TEMP_OUT_H);
		data.temp |= mpu6050_read_byte(mpu_dev.client, TEMP_OUT_L) <<8;
		break;
	}
	res = copy_to_user((void *)arg, &data, sizeof(data));//把数据拷贝到用户空间
	return sizeof(data);
}

static int dev_open(struct inode *ip, struct file *fp)
{
    return 0;
}
static int dev_release(struct inode *ip, struct file *fp)
{
    return 0;
}
struct file_operations fops = {
    .open = dev_open,
    .release = dev_release,
    .unlocked_ioctl = dev_ioctl,
};

static void mpu6050_init(struct i2c_client *client)
{
    mpu6050_write_byte(client, PWR_MGMT_1, 0x00);
    mpu6050_write_byte(client, SMPLRT_DIV, 0x07);
    mpu6050_write_byte(client, CONFIG, 0x06);
    mpu6050_write_byte(client, GYRO_CONFIG, 0x18);
    mpu6050_write_byte(client, ACCEL_CONFIG, 0x0);
}

int mpu6050_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
	mpu_dev.client = client;
	printk("xj match ok\n");
	cdev_init(&mpu_dev.cdev, &fops);
	alloc_chrdev_region(&dev_no, DEV_CNT, DEV_MI, DEV_NAME);

	cdev_add(&mpu_dev.cdev, dev_no, DEV_CNT);

	mpu6050_init(client);

	cls = class_create(THIS_MODULE, DEV_NAME);
	device_create(cls, NULL, dev_no, NULL, "%s%d", DEV_NAME, DEV_MI);
	printk("probe\n");
	return 0;
}

int mpu6050_remove(struct i2c_client *)
{
	device_destroy(cls, &dev_no);
	class_destroy(cls);
	unregister_chrdev_region(&dev_no, DEV_CNT);
	return 0;
}

struct of_device_id mpu6050_dt_match =
{
	{.compatible = "stm32,mpu6050"},
	{},
};
struct i2c_device_id mpu6050_dev_match = {

};
struct i2c_driver mpu6050_drv =
{
	.probe = mpu6050_probe,
	.remove = mpu6050_remove,
	.driver = {
		.owner = THIS_MODULE,
		.name = "mpu6050drv",
		.of_match_table = of_match_ptr(mpu6050_dt_match),
	},
	.id_table = mpu6050_dev_match,
};


module_i2c_driver(mpu6050_drv);

MODULE_LICENSE("GPL")