libata: allow LLDs w/o any reset method
Some old SFF controllers don't have any way to reset the channel.
Currently, this isn't supported and libata EH causes an oops. Allow
LLDs w/o any reset method and just assume ATA class in such cases.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 698ce2c..681252f 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -2150,6 +2150,15 @@
ap->ops->set_piomode(ap, dev);
}
+ if (!softreset && !hardreset) {
+ if (verbose)
+ ata_link_printk(link, KERN_INFO, "no reset method "
+ "available, skipping reset\n");
+ if (!(lflags & ATA_LFLAG_ASSUME_CLASS))
+ lflags |= ATA_LFLAG_ASSUME_ATA;
+ goto done;
+ }
+
/* Determine which reset to use and record in ehc->i.action.
* prereset() may examine and modify it.
*/
@@ -2254,6 +2263,7 @@
lflags |= ATA_LFLAG_ASSUME_ATA;
}
+ done:
ata_link_for_each_dev(dev, link) {
/* After the reset, the device state is PIO 0 and the
* controller state is undefined. Reset also wakes up