acpi_os_read_port 640 drivers/acpi/osl.c acpi_status acpi_os_read_port(acpi_io_address port, u32 * value, u32 width) acpi_os_read_port 1057 tools/power/acpi/os_specific/service_layers/osunixxf.c acpi_status acpi_os_read_port(acpi_io_address address, u32 *value, u32 width)