Got a cold call from a Synaptics recruiter who set me up with two technical phone interviews. Pretty typical questions you would get for firmware: describe threads, task schedulers, interrupts, semaphores, watchdog timers and their use cases. The two technical interviews led to an on-site review. This was an all day interview which included lunch, and I met with seven people who were going to be part of the team I worked with. Questions included writing C code for bit manipulations, drawing digital circuits, and how a boot loader works. Explaining the trade off between I2C and SPI was another question.