ACPI: introduce kernel parameter acpi_sleep=sci_force_enable

Introduce kernel parameter acpi_sleep=sci_force_enable

some laptop requires SCI_EN being set directly on resume,
or else they hung somewhere in the resume code path.

We already have a blacklist for these laptops but we still need
this option, especially when debugging some suspend/resume problems,
in case there are systems that need this workaround and are not yet
in the blacklist.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c
index 82e508677b9..f9961034e55 100644
--- a/arch/x86/kernel/acpi/sleep.c
+++ b/arch/x86/kernel/acpi/sleep.c
@@ -162,6 +162,8 @@ static int __init acpi_sleep_setup(char *str)
 #endif
                 if (strncmp(str, "old_ordering", 12) == 0)
                         acpi_old_suspend_ordering();
+                if (strncmp(str, "sci_force_enable", 16) == 0)
+                        acpi_set_sci_en_on_resume();
                 str = strchr(str, ',');
                 if (str != NULL)
                         str += strspn(str, ", \t");