USB: io_ti: query hardware-buffer status in chars_in_buffer
Query hardware-buffer status in chars_in_buffer should the write fifo be
empty.
This is needed to make the tty layer wait for hardware buffers to drain
on close.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/serial/io_ti.c b/drivers/usb/serial/io_ti.c
index 3abbdaa..590f27d 100644
--- a/drivers/usb/serial/io_ti.c
+++ b/drivers/usb/serial/io_ti.c
@@ -2088,6 +2088,7 @@
struct edgeport_port *edge_port = usb_get_serial_port_data(port);
int chars = 0;
unsigned long flags;
+ int ret;
if (edge_port == NULL)
return 0;
@@ -2098,6 +2099,12 @@
chars = kfifo_len(&edge_port->write_fifo);
spin_unlock_irqrestore(&edge_port->ep_lock, flags);
+ if (!chars) {
+ ret = tx_active(edge_port);
+ if (ret > 0)
+ chars = ret;
+ }
+
dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
return chars;
}