Man page 9 : i2c_add_numbered_adapter

i2c_add_numbered_adapter - declare i2c adapter, use static bus number

int i2c_add_numbered_adapter(struct i2c_adapter *  adap );

adap
    the adapter to register (with adap->nr initialized)

can sleep

This routine is used to declare an I2C adapter when its bus number matters. For example, use it for I2C adapters from system-on-chip CPUs, or otherwise built in to the systemAqs mainboard, and where i2c_board_info is used to properly configure I2C devices.

If the requested bus number is set to -1, then this function will behave identically to i2c_add_adapter, and will dynamically assign a bus number.

If no devices have pre-been declared for this bus, then be sure to register the adapter before any dynamically allocated ones. Otherwise the required bus ID may not be available.

When this returns zero, the specified adapter became available for clients using the bus number provided in adap->nr. Also, the table of I2C devices pre-declared using i2c_register_board_info is scanned, and the appropriate driver model device nodes are created. Otherwise, a negative errno value is returned.