ACPI: extend "acpi_osi=" boot option

The boot option "acpi_osi=" has always disabled Linux _OSI support,
thus disabling all OS Interface strings which are advertised
by Linux to the BIOS.

Now...
acpi_osi="string" adds the interface string, and
acpi_osi="!string" invalidates the pre-defined interface string

eg. acpi_osi="!Windows 2006"
would disable Linux's claim of Vista compatibility.

Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index aae2282600ca..79150144dca9 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -170,7 +170,10 @@ and is between 256 and 4096 characters. It is defined in the file
         acpi_os_name=   [HW,ACPI] Tell ACPI BIOS the name of the OS
                         Format: To spoof as Windows 98: ="Microsoft Windows"
 
-        acpi_osi=       [HW,ACPI] empty param disables _OSI
+        acpi_osi=       [HW,ACPI] Modify list of supported OS interface strings
+                        acpi_osi="string1"      # add string1 -- only one string
+                        acpi_osi="!string2"     # remove built-in string2
+                        acpi_osi=               # disable all strings
 
         acpi_serialize  [HW,ACPI] force serialization of AML methods