Bug 165246

Description of problem: The USB 2.0 specification requires a 10ms reset recovery
time (TRSTRCY) after
port resets before commands are issued to USB devices. However linux kernels <
2.6.11 do not implement this recovery time leading to failures on USB2.0
devices. This failure is intermittent and seen on some devices (If other system
activity causes there to be a 10ms delay between port resume and device access,
then it works, else it would fail). It also depends on the Host controller
implementation. The EHCI controller in the Broadcom HT1000 SouthBridge does not
like this violation of the spec. and fails to initialize devices.


Version-Release number of selected component (if applicable):
2.4.21-32.0.1.EL and all others

How reproducible:
Always. All USB2.0 devices fail under RHEL3.

Steps to Reproduce:
1.
2.
3.
  
Actual results:


Expected results:


Additional info:
http://marc.theaimsgroup.com/?l=linux-usb-devel&m=110859443620747&w=2

GregKH accepted this patch into the 2.6.11 kernel.

[PATCH] USB Hub driver: Add reset recovery-time delay

This patch is clearly needed for us to be in compliance with the USB spec.
It adds the mandated recovery-time delay following a port reset.
Regardless of anything else we do to alter the device initialization
sequence, this is necessary.


Signed-off-by: Alan Stern <stern.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh>


 drivers/usb/core/hub.c |    3 +++
 1 files changed, 3 insertions(+)


diff -Nru a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
--- a/drivers/usb/core/hub.c	2005-02-16 14:47:36 -08:00
+++ b/drivers/usb/core/hub.c	2005-02-16 14:47:36 -08:00
@@ -1382,6 +1382,9 @@
 		/* return on disconnect or reset */
 		switch (status) {
 		case 0:
+			/* TRSTRCY = 10 ms */
+			msleep(10);
+			/* FALL THROUGH */
 		case -ENOTCONN:
 		case -ENODEV:
 			clear_port_feature(hub->hdev,