USB: for usb_autopm_get_interface_async -EINPROGRESS is not an error

A return value of -EINPROGRESS from pm_runtime_get indicates that
the device is already resuming due to a previous call.  Internally,
usb_autopm_get_interface_async doesn't treat this as an error and
increments the usage count, but passes the error status along
to the caller.  The logical assumption of the caller is that
any negative return value reflects the device not resuming
and the pm_usage_cnt not being incremented.  Since the usage count
is being incremented and the device is resuming, return success (0)
instead.

Signed-off-by: James Wylder <james.wylder@motorola.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 34e3da5aa72a2463863b04e3b3befb4aba02505d..14b83f2a4e878f09206e18852dd275b807861bfe 100644 (file)
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -1583,7 +1583,7 @@ int usb_autopm_get_interface_async(struct usb_interface *intf)
        dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
                        __func__, atomic_read(&intf->dev.power.usage_count),
                        status);
-       if (status > 0)
+       if (status > 0 || status == -EINPROGRESS)
                status = 0;
        return status;
 }