RTC driver developed and learned by wince board-level support package

Now I am looking at the device driver while studying the kernel. Here is our real-time clock, which I understand.

1. m41t81 communicates with PXA270 through I2C bus;

2. the I2C driver is very important, including the initialization, reading, and writing of the I2C bus;

3. Various I2C controllers control initialization, read and write operations. Therefore, we need to clarify the mechanisms of each controller.

4. What we need to do below is to understand the specific code in combination with the knowledge of the I2C bus.

Call relationships between important functions in RTC are as follows: