This is a note to let you know that I've just added the patch titled
USB: Disable LPM while the device is unconfigured.
to the 3.5-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-disable-lpm-while-the-device-is-unconfigured.patch
and it can be found in the queue-3.5 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.
>From 9cf65991dd93ac3d5f97f536171c388918b7c1a9 Mon Sep 17 00:00:00 2001
From: Sarah Sharp <[email protected]>
Date: Tue, 3 Jul 2012 23:22:38 -0700
Subject: USB: Disable LPM while the device is unconfigured.
From: Sarah Sharp <[email protected]>
commit 9cf65991dd93ac3d5f97f536171c388918b7c1a9 upstream.
The USB 3.0 Set/Clear Feature U1/U2 Enable cannot be sent to a device in
the Default or Addressed state. It can only be sent to a configured
device. Change the USB core to initialize the LPM disable count to 1
(disabled), which reflects this limitation.
Change usb_set_configuration() to ensure that if the device is
unconfigured on entry, usb_lpm_disable() is not called. This avoids
sending the Clear Feature U1/U2 when the device is in the Addressed
state. When usb_set_configuration() exits with a successfully installed
configuration, usb_lpm_enable() will be called.
Once the new configuration is installed, make sure
usb_set_configuration() only calls usb_enable_lpm() if the device moved
to the Configured state. If we have unconfigured the device by sending
it a Set Configuration for config 0, don't enable LPM.
This commit should be backported to kernels as old as 3.5, that contain
the commit 8306095fd2c1100e8244c09bf560f97aca5a311d "USB: Disable USB
3.0 LPM in critical sections."
Signed-off-by: Sarah Sharp <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
drivers/usb/core/message.c | 7 ++++---
drivers/usb/core/usb.c | 1 +
2 files changed, 5 insertions(+), 3 deletions(-)
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1791,14 +1791,15 @@ free_interfaces:
* installed, so that the xHCI driver can recalculate the U1/U2
* timeouts.
*/
- if (usb_disable_lpm(dev)) {
+ if (dev->actconfig && usb_disable_lpm(dev)) {
dev_err(&dev->dev, "%s Failed to disable LPM\n.", __func__);
mutex_unlock(hcd->bandwidth_mutex);
return -ENOMEM;
}
ret = usb_hcd_alloc_bandwidth(dev, cp, NULL, NULL);
if (ret < 0) {
- usb_enable_lpm(dev);
+ if (dev->actconfig)
+ usb_enable_lpm(dev);
mutex_unlock(hcd->bandwidth_mutex);
usb_autosuspend_device(dev);
goto free_interfaces;
@@ -1818,7 +1819,7 @@ free_interfaces:
if (!cp) {
usb_set_device_state(dev, USB_STATE_ADDRESS);
usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL);
- usb_enable_lpm(dev);
+ /* Leave LPM disabled while the device is unconfigured. */
mutex_unlock(hcd->bandwidth_mutex);
usb_autosuspend_device(dev);
goto free_interfaces;
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -396,6 +396,7 @@ struct usb_device *usb_alloc_dev(struct
dev->dev.dma_mask = bus->controller->dma_mask;
set_dev_node(&dev->dev, dev_to_node(bus->controller));
dev->state = USB_STATE_ATTACHED;
+ dev->lpm_disable_count = 1;
atomic_set(&dev->urbnum, 0);
INIT_LIST_HEAD(&dev->ep0.urb_list);
Patches currently in stable-queue which might be from
[email protected] are
queue-3.5/usb-fix-lpm-disable-count-mismatch-on-driver-unbind.patch
queue-3.5/usb-disable-lpm-while-the-device-is-unconfigured.patch
queue-3.5/usb-remove-unused-lpm-variable.patch
queue-3.5/usb-fix-lpm-disable-enable-during-device-reset.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
