From: Yoshihiro Shimoda yoshihiro.shimoda.uh@renesas.com
commit 08a84410a04f05c7c1b8e833f552416d8eb9f6fe upstream.
Stop dmaengine transfer in sci_stop_tx(). Otherwise, the following message is possible output when system enters suspend and while transferring data, because clearing TIE bit in SCSCR is not able to stop any dmaengine transfer.
sh-sci e6550000.serial: ttySC1: Unable to drain transmitter
Note that this driver has already used some #ifdef in the .c file so that this patch also uses #ifdef to fix the issue. Otherwise, build errors happens if the CONFIG_SERIAL_SH_SCI_DMA is disabled.
Fixes: 73a19e4c0301 ("serial: sh-sci: Add DMA support.") Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Yoshihiro Shimoda yoshihiro.shimoda.uh@renesas.com Link: https://lore.kernel.org/r/20210610110806.277932-1-yoshihiro.shimoda.uh@renes... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/tty/serial/sh-sci.c | 8 ++++++++ 1 file changed, 8 insertions(+)
--- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -581,6 +581,14 @@ static void sci_stop_tx(struct uart_port ctrl &= ~SCSCR_TIE;
serial_port_out(port, SCSCR, ctrl); + +#ifdef CONFIG_SERIAL_SH_SCI_DMA + if (to_sci_port(port)->chan_tx && + !dma_submit_error(to_sci_port(port)->cookie_tx)) { + dmaengine_terminate_async(to_sci_port(port)->chan_tx); + to_sci_port(port)->cookie_tx = -EINVAL; + } +#endif }
static void sci_start_rx(struct uart_port *port)