From: Johan Hovold Date: Wed, 17 Mar 2010 22:06:02 +0000 (+0100) Subject: USB: serial: clean up generic write start busy test X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=50a5f70cee11636908711abd339f5c5933375a7d;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git USB: serial: clean up generic write start busy test Submit write urb if it is not already in use and we have buffered data. Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c index 63b43308e16..9756b5c22d9 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);