MTK6580M 调试ADC mcp3421 I2C接口

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概述

调试MCP3421

I2C 通道2

#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/kthread.h>
#include <linux/input.h>

#include <linux/miscdevice.h>
#include <linux/i2c.h>
#include <asm/uaccess.h>

#include <linux/of_gpio.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/wait.h>

struct i2c_client *mcp3421_i2c_client;

#define ADC_LOG pr_debug
#define MCP3421_I2C_MAX_LOOP 3

#ifndef BOOL
typedef unsigned char   BOOL;
#endif

static BOOL mcp3421_i2c_write_reg_len(unsigned char data)
{
   BOOL ack=0;
   unsigned char ret;
   unsigned char wrbuf[2];

   wrbuf[0] = data;

   ret = i2c_master_send(mcp3421_i2c_client, wrbuf, 1);
   if (ret != 1)
   {
       ADC_LOG("leo_code i2c_master_send failed %s rn", __func__);

       //dev_err(&mcp3421_i2c_client->dev,"%s: i2c_master_recv() failed, ret=%dn",__func__, ret);
       ack = 1;
   }

   ADC_LOG("leo_code mcp3421_i2c_write_reg_len() data=0x%x OKrn", data);

   return ack;
}

static BOOL mcp3421_i2c_write_reg_org(unsigned char reg,unsigned char data)
{
   BOOL ack=0;
   unsigned char ret;
   unsigned char wrbuf[2];

   wrbuf[0] = reg;
   wrbuf[1] = data;

   ret = i2c_master_send(mcp3421_i2c_client, wrbuf, 2);
   if (ret != 2)
   {
       ADC_LOG("leo_code i2c_master_send failed %s rn", __func__);

       //dev_err(&mcp3421_i2c_client->dev,"%s: i2c_master_recv() failed, ret=%dn",__func__, ret);
       ack = 1;
   }

   return ack;
}

BOOL mcp3421_i2c_write_reg(unsigned char reg,unsigned char data)
{
   BOOL ack=0;
   unsigned char i;

   for (i=0; i<MCP3421_I2C_MAX_LOOP; i++)
   {
       ack = mcp3421_i2c_write_reg_org(reg,data);
       if (ack == 0) // ack success
           break;
   }
   return ack;
}

unsigned short mcp3421_i2c_read_reg(unsigned char regaddr)
{
   unsigned char rdbuf[5], wrbuf[1], ret;

   unsigned short res=0;

   static int init_do=0;
   if(!init_do)
   {

       mcp3421_i2c_write_reg_len(0x14);
       init_do=1;

   }


   wrbuf[0] = regaddr;
/*
   int i;
   for (i=0; i<MCP3421_I2C_MAX_LOOP; i++)
   {
       ret = i2c_master_send(mcp3421_i2c_client, wrbuf, 1);
       if (ret == 1)
           break;
   }
*/
   ret = i2c_master_recv(mcp3421_i2c_client, rdbuf, 5);

   if (ret <=0)
   {
       ADC_LOG("leo_code i2c_master_recv() error rn");


       //dev_err(&mcp3421_i2c_client->dev,"%s: i2c_master_recv() failed, ret=%dn",__func__, ret);
   }

   res   = (unsigned short)rdbuf[0]<<8 |(unsigned short)rdbuf[1];

   {

   int debg_res=(int)res;

   ADC_LOG("leo_code i2c_master_recv() ret=%d : %x,%x,%x,%x:   %d rn", ret,rdbuf[0], rdbuf[1], rdbuf[2], rdbuf[3],debg_res);

   }


       return res;

}

static int mcp3421_i2c_probe(struct i2c_client *client,
                      const struct i2c_device_id *id)
{
   ADC_LOG("leo_code mcp3421_i2c_probe:OKn");

   mcp3421_i2c_client = client;

   return 0;
}

static int mcp3421_i2c_remove(struct i2c_client *client)
{
   mcp3421_i2c_client = NULL;
   return 0;
}

static const struct i2c_device_id mcp3421_i2c_id[] = {
   { "adc_i2c", 0 },
   { }
};

static const struct of_device_id adc_of_match[] = {
   {.compatible = "mediatek,adc_i2c"},
   {},
};

static struct i2c_driver mcp3421_i2c_driver = {
   .driver =
   {
       .name             = "adc_i2c",
       .of_match_table    = adc_of_match,
   },

   .probe       = mcp3421_i2c_probe,
   .remove       = (mcp3421_i2c_remove),
   .id_table        = mcp3421_i2c_id,
};
//end-Bee-20140417

static int __init hwctl_driver_init(void)
{
   int ret;

   ADC_LOG("leo_code hwctl_driver_init()n");

//   #err
//   i2c_register_board_info(1, &mcp3421_i2c_hw, 1);

   ret = i2c_add_driver(&mcp3421_i2c_driver);


   ADC_LOG("hwctl_driver_init:start n");


   return 0;
}

/* should never be called */
static void __exit hwctl_driver_exit(void)
{
       i2c_del_driver(&mcp3421_i2c_driver);
}

module_init(hwctl_driver_init);
module_exit(hwctl_driver_exit);
MODULE_DESCRIPTION("mcp3421 Linux HW direct control driver");
MODULE_AUTHOR("leo@com.cn");
MODULE_LICENSE("GPL");