Search for Raspbian Wheezy in Topics

From what I understand it will be a OS, or will it be a add-on for other operating systems?     http://www.raspberrypi.org/preview-the-upcoming-maynard-desktop/

I am new to Linux Kernel Development and I want to implement a Char device driver which handles Port expansion using a MCP23017 with a RaspberryPi (Raspbian Wheezy) using C. Here is the datesheet of mcp23017 A control for port expansion (MCP23017) is required. A less of a driver in the true sense, but more with porting functions in a driver.   The module is addressed via I2C. I need to implement the following functions in the driver: · Configuration of the I2C address · Configuration of the IOs · Configuration of Pull-Ups · Configuration of interrupts · Read / write the IOs It is important that up to 8 modules can be opened/operated simultaneously (8 is the max. possible number of addresses of the block). I have seen a number of examples in the internet and implemented a simple char device driver with init, open, read and write functions and also tested I2C operations for MCP23017. I have got a brief idea about a device driver but don't know how to further implement the functions. I would like to know/clarified about the following:     How does the dev_open work? How can I try to open a device through a linux command and check if the device is opened/ the number of times the device is opened through dmesg command?     I want 8 different modules to be opened simultaneously using the device driver and the Configuration of the MCP23017 IOs, Pullups and Interrupts. How is it done? Errors: /home/pi/i2c_gpio/mcp23017.c: In function ‘mcp23s08_direction_input’: /home/pi/i2c_gpio/mcp23017.c:269:9: error: implicit declaration of function      ‘gpiochip_get_data’ [-Werror=implicit-function-declaration] struct mcp23s08 *mcp = gpiochip_get_data(chip);      /home/pi/i2c_gpio/mcp23017.c: In function ‘mcp23s08_probe_one’: /home/pi/i2c_gpio/mcp23017.c:615:11: error: ‘struct gpio_chip’ has no         member  named ‘parent’ mcp->chip.parent = dev;                  /home/pi/i2c_gpio/mcp23017.c:681:2: error: implicit declaration of  function ‘gpiochip_add_data’ [-Werror=implicit-function-declaration] status = gpiochip_add_data(&mcp-;>chip, mcp); ^