From 1254104e1c43f837abf047215bb1ffb0722d3007 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Sun, 25 Oct 2020 18:45:49 +0100 Subject: [PATCH] USB: serial: keyspan_pda: fix stalled writes commit c01d2c58698f710c9e13ba3e2d296328606f74fd upstream. 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 # 2.6.13 Acked-by: Sebastian Andrzej Siewior Reviewed-by: Greg Kroah-Hartman Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- 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 17b60e5a9f1fe..d6ebde779e854 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; }