[PATCH 03/14] USB: serial: keyspan_pda: fix stalled writes

[Johan Hovold <johan@kernel.org>]

Make sure to clear the write-busy flag also in case no new data was
submitted due to lack of device buffer space so that writing is
resumed once space again becomes available.

Fixes: 507ca9bc0476 ("[PATCH] USB: add ability for usb-serial drivers to determine if their write urb is currently being used.")
Cc: stable <stable@vger.kernel.org>     # 2.6.13
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/usb/serial/keyspan_pda.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/serial/keyspan_pda.c b/drivers/usb/serial/keyspan_pda.c
index 17b60e5a9f1f..d6ebde779e85 100644
--- a/drivers/usb/serial/keyspan_pda.c
+++ b/drivers/usb/serial/keyspan_pda.c
@@ -548,7 +548,7 @@ static int keyspan_pda_write(struct tty_struct *tty,
 
 	rc = count;
 exit:
-	if (rc < 0)
+	if (rc <= 0)
 		set_bit(0, &port->write_urbs_free);
 	return rc;
 }
-- 
2.26.2