From: Ming Lei <ming.lei@canonical.com>
Date: Sat, 19 Jan 2013 11:30:30 +0000 (+0800)
Subject: USB: storage: avoid scanning other targets for single target device
X-Git-Tag: firefly_0821_release~3680^2~1079^2~55
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=f4cc1834bdc47d0574ceffb728f256f67e1190ef;p=firefly-linux-kernel-4.4.55.git

USB: storage: avoid scanning other targets for single target device

This patch sets scsi_host->max_id as 1 if the device's quirk
flag of US_FL_SCM_MULT_TARG isn't set, because there are only 6
mass storage devices marked as mutiple targets from unusual_devs.h.

This patch is a small optimization about scanning targets, and
avoid scanning other 7 non-existed targets for single target
device.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c
index 31b3e1a61bbd..07b3e5406f48 100644
--- a/drivers/usb/storage/usb.c
+++ b/drivers/usb/storage/usb.c
@@ -976,6 +976,9 @@ int usb_stor_probe2(struct us_data *us)
 	if (us->fflags & US_FL_SINGLE_LUN)
 		us->max_lun = 0;
 
+	if (!(us->fflags & US_FL_SCM_MULT_TARG))
+		us_to_host(us)->max_id = 1;
+
 	/* Find the endpoints and calculate pipe values */
 	result = get_pipes(us);
 	if (result)