From: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Date: Sat, 9 Jul 2011 07:04:12 +0000 (+0200)
Subject: cciss: do not attempt to read from a write-only register
X-Git-Tag: v2.6.32.44~23
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=78a4ddf99d27b83ca7b9720338b1030206db4a0e;p=linux-pvops.git

cciss: do not attempt to read from a write-only register

commit 07d0c38e7d84f911c72058a124c7f17b3c779a65 upstream.

Most smartarrays will tolerate it, but some new ones don't.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>

Note: this is a regression caused by commit 1ddd5049
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/block/cciss.h b/drivers/block/cciss.h
index 5ae1b1c4fc44..04d6bf81ccdc 100644
--- a/drivers/block/cciss.h
+++ b/drivers/block/cciss.h
@@ -165,7 +165,7 @@ static void SA5_submit_command( ctlr_info_t *h, CommandList_struct *c)
 	 printk("Sending %x - down to controller\n", c->busaddr );
 #endif /* CCISS_DEBUG */ 
          writel(c->busaddr, h->vaddr + SA5_REQUEST_PORT_OFFSET);
-	readl(h->vaddr + SA5_REQUEST_PORT_OFFSET);
+	readl(h->vaddr + SA5_SCRATCHPAD_OFFSET);
 	 h->commands_outstanding++;
 	 if ( h->commands_outstanding > h->max_outstanding)
 		h->max_outstanding = h->commands_outstanding;