From: Johan Hovold <jhovold@xxxxxxxxx> 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 5292afa657d0e790b7479ad8eef9450c1e040b3d upstream. Make sure only to decrement the PM counters if they were actually incremented. Note that the USB PM counter, but not necessarily the driver core PM counter, is reset when the interface is unbound. Fixes: 11ea859d64b6 ("USB: additional power savings for cdc-acm devices that support remote wakeup") Signed-off-by: Johan Hovold <jhovold@xxxxxxxxx> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> --- drivers/usb/class/cdc-acm.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index ebbe89f60f7b..669836ae53e0 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -575,12 +575,13 @@ static void acm_port_shutdown(struct tty_port *port) struct urb *urb; struct acm_wb *wb; int i; + int pm_err; dev_dbg(&acm->control->dev, "%s\n", __func__); mutex_lock(&acm->mutex); if (!acm->disconnected) { - usb_autopm_get_interface(acm->control); + pm_err = usb_autopm_get_interface(acm->control); acm_set_control(acm, acm->ctrlout = 0); for (;;) { @@ -598,7 +599,8 @@ static void acm_port_shutdown(struct tty_port *port) for (i = 0; i < acm->rx_buflimit; i++) usb_kill_urb(acm->read_urbs[i]); acm->control->needs_remote_wakeup = 0; - usb_autopm_put_interface(acm->control); + if (!pm_err) + usb_autopm_put_interface(acm->control); } mutex_unlock(&acm->mutex); } -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html