diff options
Diffstat (limited to 'drivers/usb/serial')
| -rw-r--r-- | drivers/usb/serial/generic.c | 15 |
1 files changed, 4 insertions, 11 deletions
diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c index 63b43308e160..9756b5c22d94 100644 --- a/drivers/usb/serial/generic.c +++ b/drivers/usb/serial/generic.c @@ -259,22 +259,15 @@ static int usb_serial_generic_write_start(struct usb_serial_port *port) int result; int count; unsigned long flags; - bool start_io; - /* Atomically determine whether we can and need to start a USB - * operation. */ spin_lock_irqsave(&port->lock, flags); - if (port->write_urb_busy) - start_io = false; - else { - start_io = (kfifo_len(&port->write_fifo) != 0); - port->write_urb_busy = start_io; + if (port->write_urb_busy || !kfifo_len(&port->write_fifo)) { + spin_unlock_irqrestore(&port->lock, flags); + return 0; } + port->write_urb_busy = 1; spin_unlock_irqrestore(&port->lock, flags); - if (!start_io) - return 0; - data = port->write_urb->transfer_buffer; count = kfifo_out_locked(&port->write_fifo, data, port->bulk_out_size, &port->lock); usb_serial_debug_data(debug, &port->dev, __func__, count, data); |