lkml.org 
[lkml]   [2016]   [Apr]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
Subject[PATCH 3.2 005/115] usb: retry reset if a device times out
3.2.80-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Oliver Neukum <oneukum@suse.com>

commit 264904ccc33c604d4b3141bbd33808152dfac45b upstream.

Some devices I got show an inability to operate right after
power on if they are already connected. They are beyond recovery
if the descriptors are requested multiple times. So in case of
a timeout we rather bail early and reset again. But it must be
done only on the first loop lest we get into a reset/time out
spiral that can be overcome with a retry.

This patch is a rework of a patch that fell through the cracks.
http://www.spinics.net/lists/linux-usb/msg103263.html

Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/usb/core/hub.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -3171,7 +3171,13 @@ hub_port_init (struct usb_hub *hub, stru
r = -EPROTO;
break;
}
- if (r == 0)
+ /*
+ * Some devices time out if they are powered on
+ * when already connected. They need a second
+ * reset. But only on the first attempt,
+ * lest we get into a time out/reset loop
+ */
+ if (r == 0 || (r == -ETIMEDOUT && j == 0))
break;
}
udev->descriptor.bMaxPacketSize0 =
\
 
 \ /
  Last update: 2016-04-27 03:01    [W:0.366 / U:2.504 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site