[PATCH] libata: ACPI and _GTF support

_GTF is an acpi method that is used to reinitialize the drive.  It returns
a task file containing ata commands that are sent back to the drive to restore
it to boot up defaults.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
(cherry picked from 9c69cab24b51a89664f4c0dfaf8a436d32117624 commit)

Documentation/kernel-parameters.txt

@@ -48,6 +48,7 @@ parameter is applicable:
 	ISAPNP	ISA PnP code is enabled.
 	ISDN	Appropriate ISDN support is enabled.
 	JOY	Appropriate joystick support is enabled.
+	LIBATA  Libata driver is enabled
 	LP	Printer support is enabled.
 	LOOP	Loopback device support is enabled.
 	M68k	M68k architecture is enabled.
@@ -1038,6 +1039,10 @@ and is between 256 and 4096 characters. It is defined in the file
 			emulation library even if a 387 maths coprocessor
 			is present.
 
+	noacpi		[LIBATA] Disables use of ACPI in libata suspend/resume
+			when set.
+			Format: <int>
+
 	noaliencache	[MM, NUMA] Disables the allcoation of alien caches in
 			the slab allocator.  Saves per-node memory, but will
 			impact performance on real NUMA hardware.

drivers/ata/Kconfig

@@ -161,6 +161,19 @@ config SATA_INTEL_COMBINED
 	depends on IDE=y && !BLK_DEV_IDE_SATA && (SATA_AHCI || ATA_PIIX)
 	default y
 
+config SATA_ACPI
+	bool
+	depends on ACPI && PCI
+	default y
+	help
+	  This option adds support for SATA-related ACPI objects.
+	  These ACPI objects add the ability to retrieve taskfiles
+	  from the ACPI BIOS and write them to the disk controller.
+	  These objects may be related to performance, security,
+	  power management, or other areas.
+	  You can disable this at kernel boot time by using the
+	  option libata.noacpi=1
+
 config PATA_ALI
 	tristate "ALi PATA support (Experimental)"
 	depends on PCI && EXPERIMENTAL

drivers/ata/Makefile

@@ -66,4 +66,4 @@ obj-$(CONFIG_ATA_GENERIC)	+= ata_generic.o
 obj-$(CONFIG_PATA_LEGACY)	+= pata_legacy.o
 
 libata-objs	:= libata-core.o libata-scsi.o libata-sff.o libata-eh.o
-
+libata-$(CONFIG_SATA_ACPI) += libata-acpi.o