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I am writing a driver for an external I2C bus device that resides on a custom computer board. There is an external connector on the device that provides an I2C bus interface. Obviously the Linux O/S does not know what device is on the bus so the driver needs to add its device to an existing bus. I have coded the following driver but the probe function is never called. What invokes the probe method to be called?

 

Code:

#ifndef __KERNEL__

# define __KERNEL__

#endif

 

#ifndef MODULE

# define MODULE

#endif

 

#include <linux/module.h>

#include <linux/init.h>

#include <linux/i2c.h>

#include <linux/platform_device.h>

#include <linux/kernel.h>

#include "io60_com4_cfg.h"

 

// Function prototypes for local functions

 

// I2C Device Info

struct i2c_board_info io60_com4_cfg_info[] = {

{

I2C_BOARD_INFO("max7310", 0x30)

},

{

I2C_BOARD_INFO("max7310", 0x32)

},

{

I2C_BOARD_INFO("max7310", 0x34)

},

};

 

struct i2c_device_id io60_com4_cfg_id[] = {

{ "max7310", 0x30 },

{ "max7310", 0x32 },

{ "max7310", 0x34 },

{}

};

MODULE_DEVICE_TABLE(i2c, io60_com4_cfg_id);

 

// Probe Module

nt io60_com4_cfg_probe(struct i2c_client *client, const struct i2c_device_id *id)

{

struct i2c_adapter *bus;

 

printk("<1>io60_com4_cfg: probed\n");

 

// Populate bus

bus = i2c_get_adapter(2);

if (!bus) {

printk("<1>io60_com4_cfg: invalid i2c adapter\n");

return -ENODEV;

}

 

memset(&io60_com4_cfg_info, 0, sizeof(struct i2c_board_info));

client = i2c_new_device(bus, io60_com4_cfg_info);

if (!client) {

printk("<1>io60_com4_cfg: unable to add i2c device\n");

return -ENODEV;

}

 

return SUCCESS;

}

 

// Remove Module

nt io60_com4_cfg_remove(struct i2c_client *client)

{

printk("<1>io60_com4_cfg: removed\n");

i2c_unregister_device(client);

}

 

// Driver Declarations

struct i2c_driver io60_com4_cfg_driver = {

.driver = {

.name = "io60_com4_cfg",

},

.probe = io60_com4_cfg_probe,

.remove = io60_com4_cfg_remove,

.id_table = io60_com4_cfg_id,

};

 

// Init Module

static int __init io60_com4_cfg_init(void)

{

// register the i2c chip driver

printk("<1>io60_com4_cfg: init executed\n");

return i2c_add_driver(&io60_com4_cfg_driver);

}

 

// Cleanup Module

static void __exit io60_com4_cfg_exit(void)

{

printk("<1>io60_com4_cfg: exit executed\n");

i2c_del_driver(&io60_com4_cfg_driver);

}

 

module_init(io60_com4_cfg_init);

module_exit(io60_com4_cfg_exit);

I attempted to move the get_adapter and add_new_device code pieces to the init function, but then the O/S will return a message that the driver does not exist.

 

Any ideas would be appreciated.

 

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