ACPI: CPPC: Return error if _CPC is invalid on a CPU
authorHoan Tran <hotran@apm.com>
Fri, 17 Jun 2016 22:16:31 +0000 (15:16 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 7 Sep 2016 06:32:38 +0000 (08:32 +0200)
commitcd84d3158f21dca9dde35f6cfb51f31dc2f4bde9
treeeea99c6c7a165e068153e357e227f2a0d4ec5f3e
parenta3043ecef71f5b880fe1b1d2aa77b3a896b86a0c
ACPI: CPPC: Return error if _CPC is invalid on a CPU

commit 8343c40d3de32ebfe8f48b043964e4ba0e7701f7 upstream.

Based on 8.4.7.1 section of ACPI 6.1 specification, if the platform
supports CPPC, the _CPC object must exist under all processor objects.
If cpc_desc_ptr pointer is invalid on any CPUs, acpi_get_psd_map()
should return error and CPPC cpufreq driver can not be registered.

Signed-off-by: Hoan Tran <hotran@apm.com>
Reviewed-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/acpi/cppc_acpi.c