libata-pmp-prep: implement sata_async_notification()
AN serves multiple purposes. For ATAPI, it's used for media change
notification. For PMP, for downstream PHY status change notification.
Implement sata_async_notification() which demultiplexes AN.
To avoid unnecessary port events, ATAPI AN is not enabled if PMP is
attached but SNTF is not available.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Kriten Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 3c31e10..60186f8 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -905,6 +905,79 @@
}
/**
+ * sata_async_notification - SATA async notification handler
+ * @ap: ATA port where async notification is received
+ *
+ * Handler to be called when async notification via SDB FIS is
+ * received. This function schedules EH if necessary.
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ *
+ * RETURNS:
+ * 1 if EH is scheduled, 0 otherwise.
+ */
+int sata_async_notification(struct ata_port *ap)
+{
+ u32 sntf;
+ int rc;
+
+ if (!(ap->flags & ATA_FLAG_AN))
+ return 0;
+
+ rc = sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf);
+ if (rc == 0)
+ sata_scr_write(&ap->link, SCR_NOTIFICATION, sntf);
+
+ if (!ap->nr_pmp_links || rc) {
+ /* PMP is not attached or SNTF is not available */
+ if (!ap->nr_pmp_links) {
+ /* PMP is not attached. Check whether ATAPI
+ * AN is configured. If so, notify media
+ * change.
+ */
+ struct ata_device *dev = ap->link.device;
+
+ if ((dev->class == ATA_DEV_ATAPI) &&
+ (dev->flags & ATA_DFLAG_AN))
+ ata_scsi_media_change_notify(dev);
+ return 0;
+ } else {
+ /* PMP is attached but SNTF is not available.
+ * ATAPI async media change notification is
+ * not used. The PMP must be reporting PHY
+ * status change, schedule EH.
+ */
+ ata_port_schedule_eh(ap);
+ return 1;
+ }
+ } else {
+ /* PMP is attached and SNTF is available */
+ struct ata_link *link;
+
+ /* check and notify ATAPI AN */
+ ata_port_for_each_link(link, ap) {
+ if (!(sntf & (1 << link->pmp)))
+ continue;
+
+ if ((link->device->class == ATA_DEV_ATAPI) &&
+ (link->device->flags & ATA_DFLAG_AN))
+ ata_scsi_media_change_notify(link->device);
+ }
+
+ /* If PMP is reporting that PHY status of some
+ * downstream ports has changed, schedule EH.
+ */
+ if (sntf & (1 << SATA_PMP_CTRL_PORT)) {
+ ata_port_schedule_eh(ap);
+ return 1;
+ }
+
+ return 0;
+ }
+}
+
+/**
* ata_eh_freeze_port - EH helper to freeze port
* @ap: ATA port to freeze
*