From 2f854b82b001b5d05b4e1c81acb947f7bd9cee9f Mon Sep 17 00:00:00 2001
From: Finn Thain <fthain@telegraphics.com.au>
Date: Sun, 3 Jan 2016 16:05:22 +1100
Subject: ncr5380: Sleep when polling, if possible

When in process context, sleep during polling if doing so won't add
significant latency. In interrupt context or if the lock is held, poll
briefly then give up. Keep both core drivers in sync.

Calibrate busy-wait iterations to allow for variation in chip register
access times between different 5380 hardware implementations.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
---
 drivers/scsi/NCR5380.h | 1 +
 1 file changed, 1 insertion(+)

(limited to 'drivers/scsi/NCR5380.h')

diff --git a/drivers/scsi/NCR5380.h b/drivers/scsi/NCR5380.h
index f9c861d083d0..412a344ac676 100644
--- a/drivers/scsi/NCR5380.h
+++ b/drivers/scsi/NCR5380.h
@@ -285,6 +285,7 @@ struct NCR5380_hostdata {
 	unsigned spin_max_w;
 #endif
 	struct workqueue_struct *work_q;
+	unsigned long accesses_per_ms;	/* chip register accesses per ms */
 };
 
 #ifdef __KERNEL__
-- 
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