[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>

1 files changed, 24 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