diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 14150767be44..256d0ebd1ac5 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4974,17 +4974,19 @@ static void ata_port_request_pm(struct ata_port *ap, pm_message_t mesg,
 	struct ata_link *link;
 	unsigned long flags;
 
-	/* Previous resume operation might still be in
-	 * progress.  Wait for PM_PENDING to clear.
-	 */
-	if (ap->pflags & ATA_PFLAG_PM_PENDING) {
-		ata_port_wait_eh(ap);
-		WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
-	}
-
-	/* request PM ops to EH */
 	spin_lock_irqsave(ap->lock, flags);
 
+	/*
+	 * A previous PM operation might still be in progress. Wait for
+	 * ATA_PFLAG_PM_PENDING to clear.
+	 */
+	if (ap->pflags & ATA_PFLAG_PM_PENDING) {
+		spin_unlock_irqrestore(ap->lock, flags);
+		ata_port_wait_eh(ap);
+		spin_lock_irqsave(ap->lock, flags);
+	}
+
+	/* Request PM operation to EH */
 	ap->pm_mesg = mesg;
 	ap->pflags |= ATA_PFLAG_PM_PENDING;
 	ata_for_each_link(link, ap, HOST_FIRST) {
@@ -4996,10 +4998,8 @@ static void ata_port_request_pm(struct ata_port *ap, pm_message_t mesg,
 
 	spin_unlock_irqrestore(ap->lock, flags);
 
-	if (!async) {
+	if (!async)
 		ata_port_wait_eh(ap);
-		WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
-	}
 }
 
 /*