[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

drivers/ata/libata-core.c

@@ -93,6 +93,10 @@ static int ata_probe_timeout = ATA_TMOUT_INTERNAL / HZ;
 module_param(ata_probe_timeout, int, 0444);
 MODULE_PARM_DESC(ata_probe_timeout, "Set ATA probing timeout (seconds)");
 
+int noacpi;
+module_param(noacpi, int, 0444);
+MODULE_PARM_DESC(noacpi, "Disables the use of ACPI in suspend/resume when set");
+
 MODULE_AUTHOR("Jeff Garzik");
 MODULE_DESCRIPTION("Library module for ATA devices");
 MODULE_LICENSE("GPL");
@@ -1778,6 +1782,9 @@ int ata_bus_probe(struct ata_port *ap)
 	/* reset and determine device classes */
 	ap->ops->phy_reset(ap);
 
+	/* retrieve and execute the ATA task file of _GTF */
+	ata_acpi_exec_tfs(ap);
+
 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
 		dev = &ap->device[i];
 

drivers/ata/libata.h

@@ -47,6 +47,7 @@ extern struct workqueue_struct *ata_aux_wq;
 extern int atapi_enabled;
 extern int atapi_dmadir;
 extern int libata_fua;
+extern int noacpi;
 extern struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev);
 extern int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
 			   u64 block, u32 n_block, unsigned int tf_flags,
@@ -87,6 +88,15 @@ extern void ata_port_init(struct ata_port *ap, struct ata_host *host,
 extern struct ata_probe_ent *ata_probe_ent_alloc(struct device *dev,
 						 const struct ata_port_info *port);
 
+/* libata-acpi.c */
+#ifdef CONFIG_SATA_ACPI
+extern int ata_acpi_exec_tfs(struct ata_port *ap);
+#else
+static inline int ata_acpi_exec_tfs(struct ata_port *ap)
+{
+	return 0;
+}
+#endif
 
 /* libata-scsi.c */
 extern struct scsi_transport_template ata_scsi_transport_template;

include/linux/libata.h

@@ -35,6 +35,7 @@
 #include <linux/ata.h>
 #include <linux/workqueue.h>
 #include <scsi/scsi_host.h>
+#include <linux/acpi.h>
 
 /*
  * Define if arch has non-standard setup.  This is a _PCI_ standard
@@ -495,6 +496,10 @@ struct ata_device {
 	/* error history */
 	struct ata_ering	ering;
 	unsigned int		horkage;	/* List of broken features */
+#ifdef CONFIG_SATA_ACPI
+	/* ACPI objects info */
+	acpi_handle obj_handle;
+#endif
 };
 
 /* Offset into struct ata_device.  Fields above it are maintained