mine, works fine. i use the defconfig. change nothing.
#
# ACPI Support
#
CONFIG_ACPI=y
# CONFIG_ACPI_HT_ONLY is not set
CONFIG_ACPI_BOOT=y
CONFIG_ACPI_AC=y
CONFIG_ACPI_BATTERY=y
CONFIG_ACPI_BUTTON=y
CONFIG_ACPI_FAN=y
CONFIG_ACPI_PROCESSOR=y
CONFIG_ACPI_THERMAL=y