[libata] EH: freeze port before aborting commands
Call the ->freeze() hook before aborting qc's, because some hardware
requires special handling prior to accessing the taskfile registers
(for diagnosis/analysis/reset). Most notably, hardware may wish to
disable the DMA engine or interrupts in the ->freeze() hook.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 79711b6..9159abe 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -999,7 +999,9 @@
* ata_port_freeze - abort & freeze port
* @ap: ATA port to freeze
*
- * Abort and freeze @ap.
+ * Abort and freeze @ap. The freeze operation must be called
+ * first, because some hardware requires special operations
+ * before the taskfile registers are accessible.
*
* LOCKING:
* spin_lock_irqsave(host lock)
@@ -1013,8 +1015,8 @@
WARN_ON(!ap->ops->error_handler);
- nr_aborted = ata_port_abort(ap);
__ata_port_freeze(ap);
+ nr_aborted = ata_port_abort(ap);
return nr_aborted;
}