做预算查价格的网站是哪个,定西企业网站制作,好网站123,微网站怎么做一.SD5075芯片简介
SD5075 是一款高准确度温度传感器芯片内含高精度测温 ADC#xff0c;在-40C ~100C 范围内典型误差小于0.5C#xff0c;在-55C~125C 范围内典型误差小于士1.0C。通过两线 IC/SMBus接口可以很方便与其他设备建立通信。设置 A2~A0 的地址线#xff0c;可支持…一.SD5075芯片简介
SD5075 是一款高准确度温度传感器芯片内含高精度测温 ADC在-40C ~100°C 范围内典型误差小于0.5°C在-55C~125°C 范围内典型误差小于士1.0°C。通过两线 IC/SMBus接口可以很方便与其他设备建立通信。设置 A2~A0 的地址线可支持8 片芯片并联总线连接 本芯片可选 3 种工作模式: 连续测温模式单次测温模式关断模式。可根据速度或功耗的需求灵活选择和配置。
管脚描述 二.SD5075温度检测原理 原理
SD5075芯片经过ALARM引脚检测温度的变化经过模数转换器的转换把温度值写入寄存器中SOC再通过IIC读取寄存器的值从而拿到温度值。
寄存器列表 通过配置0x01寄存器为0x00通过寄存器0x00读取到温度结果。
三.代码实现
#include linux/miscdevice.h
#include linux/cdev.h
#include linux/device.h
#include linux/fs.h
#include linux/i2c-dev.h
#include linux/i2c.h
#include linux/init.h
#include linux/kernel.h
#include linux/module.h
#include linux/notifier.h
#include linux/slab.h
#include linux/uaccess.h
#include linux/compat.h
#include linux/printk.h
#include linux/kobject.h
#include linux/version.h#define DRIVER_VERSION KERNEL_VERSION(0, 0x01, 0x00)
#define DRIVER_NAME IST_TEMP/*define logging*/
#define IST_TEMP_DEBUG 0
#if IST_TEMP_DEBUG
#define DBG(format, args...) \printk(KERN_DEBUG %s: format, DRIVER_NAME, ##args)
#define ERR(format, args...) \printk(KERN_ERR %s: format, DRIVER_NAME, ##args)
#define WARNING(format, args...) \printk(KERN_WARN %s: format, DRIVER_NAME, ##args)
#define INFO(format, args...) \printk(KERN_INFO %s: format, DRIVER_NAME, ##args)
#else
#define DBG(format, args...)
#define ERR(format, args...)
#define WARNING(format, args...)
#define INFO(format, args...)
#endifstruct temp_dev {struct device *dev;struct miscdevice miscdev;struct i2c_client *client;u32 value;
};struct temp_dev *g_temp;
struct temp_dev *temp;
static int last_value 0;//charstatic void i2c_wr(struct temp_dev *temp, u16 reg, u8 *val, u32 n)
{struct i2c_msg msg;struct i2c_client *client temp-client;int err;u8 data[128];data[0] reg;memcpy(data[1], val, n);msg.addr client-addr;msg.flags 0;msg.buf data;msg.len n 1;err i2c_transfer(client-adapter, msg, 1);if (err ! 1) {ERR(%s: writing register 0x%x from 0x%x failed\n, __func__,reg, client-addr);} else {switch (n) {case 1:INFO(I2C write 0x%02x 0x%02x\n, reg, data[1]);break;case 2:INFO(I2C write 0x%02x 0x%02x%02x\n, reg, data[2],data[1]);break;case 4:INFO(I2C write 0x%02x 0x%02x%02x%02x%02x\n, reg,data[4], data[3], data[2], data[1]);break;default:INFO(I2C write %d bytes from address 0x%02x\n, n,reg);}}
}static void i2c_rd(struct temp_dev *temp, u16 reg, u8 *val, u32 n)
{struct i2c_msg msg[2];struct i2c_client *client temp-client;int err;u8 buf[1] { reg };/*msg[0] addr to read*/msg[0].addr client-addr;msg[0].flags 0;msg[0].buf buf;msg[0].len 1;/*msg[1] read data*/msg[1].addr client-addr;msg[1].flags I2C_M_RD;msg[1].buf val;msg[1].len n;err i2c_transfer(client-adapter, msg, ARRAY_SIZE(msg));if (err ! ARRAY_SIZE(msg)) {ERR(%s: reading register 0x%x from 0x%x failed\n, __func__,reg, client-addr);}
}static void i2c_rd8(struct temp_dev *temp, u16 reg, u8 *val)
{i2c_rd(temp, reg, val, 1);
}static void i2c_wr8(struct temp_dev *temp, u16 reg, u8 buf)
{i2c_wr(temp, reg, buf, 1);
}static void i2c_wr_word(struct temp_dev *temp, u16 reg, u16 val)
{unsigned char data[2] {0};data[0] (unsigned char)(val 0xFF);data[1] (unsigned char)((val 0xFF00) 8);i2c_wr(temp, reg, data, 2);
}static void i2c_rd_word(struct temp_dev *temp, u16 reg, u8 *val)
{i2c_rd(temp, reg, val, 2);
}static long temperature_ioctl(struct file *file, uint32_t cmd, unsigned long arg)
{return 0;
}static ssize_t temperature_write(struct file *file, const char __user *buf,size_t size, loff_t *ppos)
{return 1;
}static ssize_t temperature_read(struct file *file, char __user *buf, size_t size,loff_t *ppos)
{return 1;
}static ssize_t temperature_value_read(struct device *dev,struct device_attribute *attr, char *buf)
{struct temp_dev *temp g_temp;int result -1;unsigned char reg;unsigned char reg_value;unsigned short value 0;unsigned char value1[2] {0};reg 0x01;reg_value 0x00;i2c_wr8(temp, reg, reg_value);reg 0x00;i2c_rd_word(temp, reg, value1);value (value1[0]8|value1[1])4;if(value 0x800){printk( temperature_value_read !!!);value (value - 2048)4;result value - 128;}else{result value4;printk( temperature_value_read !!!);}if(result -1){result - last_value;printk( temperature_value_read !!!);if((result 8) || (result (-8))){result last_value;}else{result -1;}}temp-value result;return sprintf(buf, %d\n, temp-value);
}static ssize_t temperature_value_write(struct device *dev,struct device_attribute *attr,const char *buf, size_t count)
{return count;
}static DEVICE_ATTR(value, 0644,temperature_value_read, temperature_value_write);static void temp_init(struct temp_dev *temp)
{}static const struct file_operations temp_fops {.owner THIS_MODULE,.read temperature_read,.write temperature_write,.unlocked_ioctl temperature_ioctl,
};struct miscdevice temp_miscdev {.minor MISC_DYNAMIC_MINOR,.name temp_dev,.fops temp_fops,
};static int temp_probe(struct i2c_client *client,const struct i2c_device_id *id)
{struct temp_dev *temp;struct device *dev client-dev;int ret;dev_info(dev, driver version: %02x.%02x.%02x,DRIVER_VERSION 16,(DRIVER_VERSION 0xff00) 8,DRIVER_VERSION 0x00ff);if (!i2c_check_functionality(client-adapter, I2C_FUNC_SMBUS_BYTE_DATA))return -EIO;DBG(chip found 0x%x (%s)\n, client-addr 1,client-adapter-name);temp devm_kzalloc(dev, sizeof(struct temp_dev), GFP_KERNEL);if (!temp)return -ENOMEM;temp-client client;client-flags | I2C_CLIENT_SCCB;ret misc_register(temp_miscdev);if (ret) {ERR( temp ERROR: could not register ist_temp device\n);return ret;}ret device_create_file(temp_miscdev.this_device,dev_attr_value);if (ret) {dev_err(temp-dev, failed to create attr hdmirxsel!\n);return ret;}temp_init(temp);g_temp temp;INFO(%s found 0x%x (%s)\n, client-name, client-addr 1,client-adapter-name);return 0;
}static int temp_remove(struct i2c_client *client)
{misc_deregister(temp_miscdev);kfree(temp);return 0;
}static const struct of_device_id temp_of_match[] {{ .compatible temperature },{}
};
MODULE_DEVICE_TABLE(of, temp_of_match);static struct i2c_driver temp_driver {.probe temp_probe,.remove temp_remove,.driver {.owner THIS_MODULE,.name DRIVER_NAME,.of_match_table of_match_ptr(temp_of_match),},
};static int __init temp_driver_init(void)
{return i2c_add_driver(temp_driver);
}static void __exit temp_driver_exit(void)
{i2c_del_driver(ist_temp_driver);
}device_initcall_sync(temp_driver_init);
module_exit(temp_driver_exit);MODULE_DESCRIPTION(temperature sensor);
MODULE_AUTHOR();
MODULE_LICENSE(GPL v2);
