[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>

drivers/ata/libata-core.c

@@ -70,6 +70,7 @@ const unsigned long sata_deb_timing_long[]		= { 100, 2000, 5000 };
 static unsigned int ata_dev_init_params(struct ata_device *dev,
 					u16 heads, u16 sectors);
 static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
+static unsigned int ata_dev_set_AN(struct ata_device *dev, u8 enable);
 static void ata_dev_xfermask(struct ata_device *dev);
 static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
 
@@ -1987,6 +1988,22 @@ int ata_dev_configure(struct ata_device *dev)
 		}
 		dev->cdb_len = (unsigned int) rc;
 
+		/*
+		 * check to see if this ATAPI device supports
+		 * Asynchronous Notification
+		 */
+		if ((ap->flags & ATA_FLAG_AN) && ata_id_has_AN(id)) {
+			int err;
+			/* issue SET feature command to turn this on */
+			err = ata_dev_set_AN(dev, SETFEATURES_SATA_ENABLE);
+			if (err)
+				ata_dev_printk(dev, KERN_ERR,
+						"unable to set AN, err %x\n",
+						err);
+			else
+				dev->flags |= ATA_DFLAG_AN;
+		}
+
 		if (ata_id_cdb_intr(dev->id)) {
 			dev->flags |= ATA_DFLAG_CDB_INTR;
 			cdb_intr_string = ", CDB intr";
@@ -3974,6 +3991,42 @@ static unsigned int ata_dev_set_xfermode(struct ata_device *dev)
 	return err_mask;
 }
 
+/**
+ *	ata_dev_set_AN - Issue SET FEATURES - SATA FEATURES
+ *	@dev: Device to which command will be sent
+ *	@enable: Whether to enable or disable the feature
+ *
+ *	Issue SET FEATURES - SATA FEATURES command to device @dev
+ *	on port @ap with sector count set to indicate Asynchronous
+ *	Notification feature
+ *
+ *	LOCKING:
+ *	PCI/etc. bus probe sem.
+ *
+ *	RETURNS:
+ *	0 on success, AC_ERR_* mask otherwise.
+ */
+static unsigned int ata_dev_set_AN(struct ata_device *dev, u8 enable)
+{
+	struct ata_taskfile tf;
+	unsigned int err_mask;
+
+	/* set up set-features taskfile */
+	DPRINTK("set features - SATA features\n");
+
+	ata_tf_init(dev, &tf);
+	tf.command = ATA_CMD_SET_FEATURES;
+	tf.feature = enable;
+	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
+	tf.protocol = ATA_PROT_NODATA;
+	tf.nsect = SATA_AN;
+
+	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0);
+
+	DPRINTK("EXIT, err_mask=%x\n", err_mask);
+	return err_mask;
+}
+
 /**
  *	ata_dev_init_params - Issue INIT DEV PARAMS command
  *	@dev: Device to which command will be sent

include/linux/ata.h

@@ -230,6 +230,12 @@ enum {
 
 	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 @@ struct ata_taskfile {
 #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)	\

include/linux/libata.h

@@ -139,6 +139,7 @@ enum {
 	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 @@ enum {
 	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