Merge branch 'acpica'

* acpica:
  ACPICA: Update version to 20130725.
  ACPICA: Update names for walk_namespace callbacks to clarify usage.
  ACPICA: Return error if DerefOf resolves to a null package element.
  ACPICA: Make ACPI Power Management Timer (PM Timer) optional.
  ACPICA: Fix divergences of the commit - ACPICA: Expose OSI version.
  ACPICA: Fix possible fault for methods that optionally have no return value.
  ACPICA: DeRefOf operator: Update to fully resolve FieldUnit and BufferField refs.
  ACPICA: Emit all unresolved method externals in a text block
  ACPICA: Export acpi_tb_validate_rsdp().
  ACPI: Add facility to remove all _OSI strings
  ACPI: Add facility to disable all _OSI OS vendor strings
  ACPICA: Add acpi_update_interfaces() public interface
  ACPICA: Update version to 20130626
  ACPICA: Fix compiler warnings for casting issues (only some compilers)
  ACPICA: Remove restriction of 256 maximum GPEs in any GPE block
  ACPICA: Disassembler: Expand maximum output string length to 64K
  ACPICA: TableManager: Export acpi_tb_scan_memory_for_rsdp()
  ACPICA: Update comments about behavior when _STA does not exist

1 files changed, 53 insertions, 2 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 7f9d4f53882c..03c196d90da3 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -235,10 +235,61 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			Format: To spoof as Windows 98: ="Microsoft Windows"
 
 	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="string1"	# add string1
+			acpi_osi="!string2"	# remove string2
+			acpi_osi=!*		# remove all strings
+			acpi_osi=!		# disable all built-in OS vendor
+						  strings
 			acpi_osi=		# disable all strings
 
+			'acpi_osi=!' can be used in combination with single or
+			multiple 'acpi_osi="string1"' to support specific OS
+			vendor string(s).  Note that such command can only
+			affect the default state of the OS vendor strings, thus
+			it cannot affect the default state of the feature group
+			strings and the current state of the OS vendor strings,
+			specifying it multiple times through kernel command line
+			is meaningless.  This command is useful when one do not
+			care about the state of the feature group strings which
+			should be controlled by the OSPM.
+			Examples:
+			  1. 'acpi_osi=! acpi_osi="Windows 2000"' is equivalent
+			     to 'acpi_osi="Windows 2000" acpi_osi=!', they all
+			     can make '_OSI("Windows 2000")' TRUE.
+
+			'acpi_osi=' cannot be used in combination with other
+			'acpi_osi=' command lines, the _OSI method will not
+			exist in the ACPI namespace.  NOTE that such command can
+			only affect the _OSI support state, thus specifying it
+			multiple times through kernel command line is also
+			meaningless.
+			Examples:
+			  1. 'acpi_osi=' can make 'CondRefOf(_OSI, Local1)'
+			     FALSE.
+
+			'acpi_osi=!*' can be used in combination with single or
+			multiple 'acpi_osi="string1"' to support specific
+			string(s).  Note that such command can affect the
+			current state of both the OS vendor strings and the
+			feature group strings, thus specifying it multiple times
+			through kernel command line is meaningful.  But it may
+			still not able to affect the final state of a string if
+			there are quirks related to this string.  This command
+			is useful when one want to control the state of the
+			feature group strings to debug BIOS issues related to
+			the OSPM features.
+			Examples:
+			  1. 'acpi_osi="Module Device" acpi_osi=!*' can make
+			     '_OSI("Module Device")' FALSE.
+			  2. 'acpi_osi=!* acpi_osi="Module Device"' can make
+			     '_OSI("Module Device")' TRUE.
+			  3. 'acpi_osi=! acpi_osi=!* acpi_osi="Windows 2000"' is
+			     equivalent to
+			     'acpi_osi=!* acpi_osi=! acpi_osi="Windows 2000"'
+			     and
+			     'acpi_osi=!* acpi_osi="Windows 2000" acpi_osi=!',
+			     they all will make '_OSI("Windows 2000")' TRUE.
+
 	acpi_pm_good	[X86]
 			Override the pmtimer bug detection: force the kernel
 			to assume that this machine's pmtimer latches its value