[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>

3 files changed, 43 insertions, 0 deletions

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 483733783cf8..d52b73ab795a 100644
--- a/drivers/ata/ahci.c
+++ b/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
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 7d66c986a54c..f0f586b56c20 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -3160,6 +3160,24 @@ 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
  *
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 6dd5b437210d..d98e8b50e20c 100644
--- a/include/linux/libata.h
+++ b/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 *);