• Rajneesh Bhardwaj's avatar
    ACPI / PM: LPIT: Register sysfs attributes based on FADT · 1cdda948
    Rajneesh Bhardwaj authored
    ACPI Low Power S0 Idle capabilities are announced via FADT table and can
    be used to inform the kernel about the presence of one or more Low Power
    Idle (LPI) entries as descried in LPIT table. LPIT table can exist
    independently even if the FADT S0 Idle flag is not set and thus it could
    confuse user since the following cpuidle attributes are created.
    
    /sys/devices/system/cpu/cpuidle/low_power_idle_cpu_residency_us
    /sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us
    
    Presence or absence of above attributes could mean that the given
    platform supports S0ix state or not.
    
    This change allows to create the above cpuidle attributes only if
    FADT table supports Low Power S0 Idle.
    Signed-off-by: default avatarRajneesh Bhardwaj <rajneesh.bhardwaj@linux.intel.com>
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    1cdda948
acpi_lpit.c 4.63 KB