[SCSI] hpsa: do not attempt to read from a write-only register

Most smartarrays tolerate it, but a few new ones don't.
Without this change some newer Smart Arrays will lock up
and i/o will grind to a halt.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
Stephen M. Cameron 2011-07-21 13:16:05 -05:00 committed by James Bottomley
parent 8ead0bd175
commit fec62c368b

View file

@ -214,7 +214,7 @@ static void SA5_submit_command(struct ctlr_info *h,
dev_dbg(&h->pdev->dev, "Sending %x, tag = %x\n", c->busaddr,
c->Header.Tag.lower);
writel(c->busaddr, h->vaddr + SA5_REQUEST_PORT_OFFSET);
(void) readl(h->vaddr + SA5_REQUEST_PORT_OFFSET);
(void) readl(h->vaddr + SA5_SCRATCHPAD_OFFSET);
h->commands_outstanding++;
if (h->commands_outstanding > h->max_outstanding)
h->max_outstanding = h->commands_outstanding;