USB: serial: sierra: use irqsave() in USB's complete callback

The USB completion callback does not disable interrupts while acquiring
the lock. We want to remove the local_irq_disable() invocation from
__usb_hcd_giveback_urb() and therefore it is required for the callback
handler to disable the interrupts while acquiring the lock.
The callback may be invoked either in IRQ or BH context depending on the
USB host controller.
Use the _irqsave() variant of the locking primitives.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Johan Hovold <johan@kernel.org>

diff --git a/drivers/usb/serial/sierra.c b/drivers/usb/serial/sierra.c
index 55956a638f5b7dcad4849806c7a3c02de200c8c0..a43263a0edd88e2e61521907ae6baff55b2af32d 100644 (file)
--- a/drivers/usb/serial/sierra.c
+++ b/drivers/usb/serial/sierra.c
@@ -409,6 +409,7 @@ static void sierra_outdat_callback(struct urb *urb)
        struct sierra_port_private *portdata = usb_get_serial_port_data(port);
        struct sierra_intf_private *intfdata;
        int status = urb->status;
+       unsigned long flags;
 
        intfdata = usb_get_serial_data(port->serial);
 
@@ -419,12 +420,12 @@ static void sierra_outdat_callback(struct urb *urb)
                dev_dbg(&port->dev, "%s - nonzero write bulk status "
                    "received: %d\n", __func__, status);
 
-       spin_lock(&portdata->lock);
+       spin_lock_irqsave(&portdata->lock, flags);
        --portdata->outstanding_urbs;
-       spin_unlock(&portdata->lock);
-       spin_lock(&intfdata->susp_lock);
+       spin_unlock_irqrestore(&portdata->lock, flags);
+       spin_lock_irqsave(&intfdata->susp_lock, flags);
        --intfdata->in_flight;
-       spin_unlock(&intfdata->susp_lock);
+       spin_unlock_irqrestore(&intfdata->susp_lock, flags);
 
        usb_serial_port_softint(port);
 }