Hi Johan, > > Can you please explain why this would not a problem for all future > transactions as well? > > If it is, then it sounds like this needs to be addressed in the i2c > driver. If not, then perhaps the problem is really that you just need a > delay after enabling the power supplies? > The problem is that the probe function calling i2c_smbus_read_byte() is not aware that uC on the other end is in a deep sleep state so the first read will fail and so the whole probe. In a normal scenario, when a user touches the touchpad (when it is in a deep sleep), the touch will first wake up the uC and then generate an interrupt to AP, so in this case the touchpad is fully awake and operational. > Nit: move above the 'ret' declaration to maintain reverse xmas style > ordering. > > Johan Will do so. Kind regards, Lukasz
