If the "baseband" is a stand-alone chip, it tends to have a large firmware and complex interactions over some local bus such as simple UART. The power states of the chip is also driven from userspace, making power-saving scenarious uncoordinated with kernel power management for the most part. Assisted GPS requires network connectivity over cellular data and special interactions with a cellular modem to work. Stand-alone GPS chips for devices without cellular modems such as tablets also exist. Whether the[…]
