diff options
| author | Alan Stern <stern@rowland.harvard.edu> | 2014-05-21 05:08:07 +0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-05-28 03:28:03 +0400 |
| commit | 600856c231ccb0cbf8afcf09066a8ab2a93ab03d (patch) | |
| tree | aa8e9074adccb30ecbd6ac8aa2dce377e0c5a834 /drivers/usb/core/hub.h | |
| parent | 342a74934197386e065e8ef00014e6f0cb5effe6 (diff) | |
| download | linux-600856c231ccb0cbf8afcf09066a8ab2a93ab03d.tar.xz | |
USB: mutual exclusion for resetting a hub and power-managing a port
The USB core doesn't properly handle mutual exclusion between
resetting a hub and changing the power states of the hub's ports. We
need to avoid sending port-power requests to the hub while it is being
reset, because such requests cannot succeed.
This patch fixes the problem by keeping track of when a reset is in
progress. At such times, attempts to suspend (power-off) a port will
fail immediately with -EBUSY, and calls to usb_port_runtime_resume()
will update the power_is_on flag and return immediately. When the
reset is complete, hub_activate() will automatically restore each port
to the proper power state.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/core/hub.h')
| -rw-r--r-- | drivers/usb/core/hub.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h index 33bcb2c6f90a..f9b521e60128 100644 --- a/drivers/usb/core/hub.h +++ b/drivers/usb/core/hub.h @@ -66,6 +66,7 @@ struct usb_hub { unsigned limited_power:1; unsigned quiescing:1; unsigned disconnected:1; + unsigned in_reset:1; unsigned quirk_check_port_auto_suspend:1; |