[libata] ahci: send event when AN received

When we get an SDB FIS with the 'N' bit set, we should send
an event to user space to indicate that there has been a
media change.  This will be done via the scsi device.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/ata/ahci.c

@@ -1368,6 +1368,30 @@ static void ahci_port_intr(struct ata_port *ap)
 		return;
 	}
 
+	if (status & PORT_IRQ_SDB_FIS) {
+		/*
+		 * if this is an ATAPI device with AN turned on,
+		 * then we should interrogate the device to
+		 * determine the cause of the interrupt
+		 *
+		 * for AN - this we should check the SDB FIS
+		 * and find the I and N bits set
+		 */
+		const __le32 *f = pp->rx_fis + RX_FIS_SDB;
+		u32 f0 = le32_to_cpu(f[0]);
+
+		/* check the 'N' bit in word 0 of the FIS */
+		if (f0 & (1 << 15)) {
+			int port_addr = ((f0 & 0x00000f00) >> 8);
+			struct ata_device *adev;
+			if (port_addr < ATA_MAX_DEVICES) {
+				adev = &ap->link.device[port_addr];
+				if (adev->flags & ATA_DFLAG_AN)
+					ata_scsi_media_change_notify(adev);
+			}
+		}
+	}
+
 	if (ap->link.sactive)
 		qc_active = readl(port_mmio + PORT_SCR_ACT);
 	else

drivers/ata/libata-scsi.c

@@ -3159,6 +3159,24 @@ static void ata_scsi_handle_link_detach(struct ata_link *link)
 	}
 }
 
+/**
+ *	ata_scsi_media_change_notify - send media change event
+ *	@atadev: Pointer to the disk device with media change event
+ *
+ *	Tell the block layer to send a media change notification
+ *	event.
+ *
+ * 	LOCKING:
+ * 	interrupt context, may not sleep.
+ */
+void ata_scsi_media_change_notify(struct ata_device *atadev)
+{
+#ifdef OTHER_AN_PATCHES_HAVE_BEEN_APPLIED
+	scsi_device_event_notify(atadev->sdev, SDEV_MEDIA_CHANGE);
+#endif
+}
+EXPORT_SYMBOL_GPL(ata_scsi_media_change_notify);
+
 /**
  *	ata_scsi_hotplug - SCSI part of hotplug
  *	@work: Pointer to ATA port to perform SCSI hotplug on

include/linux/libata.h

@@ -755,6 +755,7 @@ extern void ata_host_init(struct ata_host *, struct device *,
 extern int ata_scsi_detect(struct scsi_host_template *sht);
 extern int ata_scsi_ioctl(struct scsi_device *dev, int cmd, void __user *arg);
 extern int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *));
+extern void ata_scsi_media_change_notify(struct ata_device *atadev);
 extern void ata_sas_port_destroy(struct ata_port *);
 extern struct ata_port *ata_sas_port_alloc(struct ata_host *,
 					   struct ata_port_info *, struct Scsi_Host *);