In message 20641.216.110.51.8.1078416617.squirrel@www.orkun.us you wrote:
Just configure the I2C clock for the maximum allowable speed right from the beginning.
You can have 100khz and 400khz capable devices accessible to the master. You can run everything at 100khz but you will not be taking full advantange of 400khz devices.
Rigth. But on such a system you cannot run the bus at 400 kHz as this would be out of spec for the 100 kHz devices.
Philips AN10216-01 (I2C Manual) Dated March 24, 2003, Page 24 describes how a system can run both 100kHz devices and 400kHz devices on the same bus and access 400kHz devices at 400kHz using I2C bus repeater such as PCA9515.
I understand this might not be useful for everyone so that is why I proposed to make it an optional command that is compiled in only if CONFIG_I2C_ISPEED is defined.
I don't think this is useful.
What exactly are you trying to do that the speed makes any difference for you? Remember, this is a boot loader, not an operating system.
Best regards,
Wolfgang Denk