linux-kernelporthardwarepcibus

Are PS/2 devices port mapped I/O devices?

Are PS/2 devices like old-style mice and keyboard are port mapped I/O devices? Are there any PCI or USB devices which can be functioning as port mapped I/O devices?

Solution

  • The PS/2 keyboard controller is accessed via I/O ports 60h and 64h.

    PCI and PCIe devices can provide either MMIO mapped or I/O mapped address ranges or both.

    USB devices can only be accessed via the USB controller, which uses MMIO, not I/O ports.