[libata] check for SATA async notify support

Check to see if an ATAPI device supports Asynchronous Notification.
If so, enable it, if the host controller supports AN.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/include/linux/ata.h b/include/linux/ata.h
index 40c7af0..fba8e14 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -230,6 +230,12 @@
 
 	SETFEATURES_SPINUP	= 0x07, /* Spin-up drive */
 
+	SETFEATURES_SATA_ENABLE = 0x10, /* Enable use of SATA feature */
+	SETFEATURES_SATA_DISABLE = 0x90, /* Disable use of SATA feature */
+
+	/* SETFEATURE Sector counts for SATA features */
+	SATA_AN			= 0x05,  /* Asynchronous Notification */
+
 	/* ATAPI stuff */
 	ATAPI_PKT_DMA		= (1 << 0),
 	ATAPI_DMADIR		= (1 << 2),	/* ATAPI data dir:
@@ -357,6 +363,9 @@
 #define ata_id_queue_depth(id)	(((id)[75] & 0x1f) + 1)
 #define ata_id_removeable(id)	((id)[0] & (1 << 7))
 #define ata_id_has_dword_io(id)	((id)[50] & (1 << 0))
+#define ata_id_has_AN(id)	\
+	( (((id)[76] != 0x0000) && ((id)[76] != 0xffff)) && \
+	  ((id)[78] & (1 << 5)) )
 #define ata_id_iordy_disable(id) ((id)[49] & (1 << 10))
 #define ata_id_has_iordy(id) ((id)[49] & (1 << 11))
 #define ata_id_u32(id,n)	\
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 7a1793b..6dd5b43 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -139,6 +139,7 @@
 	ATA_DFLAG_FLUSH_EXT	= (1 << 4), /* do FLUSH_EXT instead of FLUSH */
 	ATA_DFLAG_ACPI_PENDING	= (1 << 5), /* ACPI resume action pending */
 	ATA_DFLAG_ACPI_FAILED	= (1 << 6), /* ACPI on devcfg has failed */
+	ATA_DFLAG_AN		= (1 << 7), /* device supports AN */
 	ATA_DFLAG_CFG_MASK	= (1 << 8) - 1,
 
 	ATA_DFLAG_PIO		= (1 << 8), /* device limited to PIO mode */
@@ -179,6 +180,7 @@
 	ATA_FLAG_IGN_SIMPLEX	= (1 << 15), /* ignore SIMPLEX */
 	ATA_FLAG_NO_IORDY	= (1 << 16), /* controller lacks iordy */
 	ATA_FLAG_ACPI_SATA	= (1 << 17), /* need native SATA ACPI layout */
+	ATA_FLAG_AN		= (1 << 18), /* controller supports AN */
 
 	/* The following flag belongs to ap->pflags but is kept in
 	 * ap->flags because it's referenced in many LLDs and will be