> -----Original Message-----
> From: Sherry Sun <sherry.sun@xxxxxxx>
> Sent: Sunday, May 21, 2023 9:51 PM
> To: gregkh@xxxxxxxxxxxxxxxxxxx; jirislaby@xxxxxxxxxx; Shenwei Wang
> <shenwei.wang@xxxxxxx>; ilpo.jarvinen@xxxxxxxxxxxxxxx
> Cc: linux-serial@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; dl-linux-imx
> <linux-imx@xxxxxxx>
> Subject: [PATCH] tty: serial: fsl_lpuart: Check the return value of
> dmaengine_tx_status
>
> Coverity reports the Unchecked return value (CHECKED_RETURN) warning:
> Calling dmaengine_tx_status without checking return value.
>
> So here add the return value check for dmaengine_tx_status() function to make
> coverity happy.
>
> Fixes: cf9aa72d2f91 ("tty: serial: fsl_lpuart: optimize the timer based EOP logic")
> Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx>
> ---
> drivers/tty/serial/fsl_lpuart.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index
> 92a3bd0f4158..f2a47a8c5b85 100644
> --- a/drivers/tty/serial/fsl_lpuart.c
> +++ b/drivers/tty/serial/fsl_lpuart.c
> @@ -1286,13 +1286,19 @@ static void lpuart_dma_rx_complete(void *arg)
> static void lpuart_timer_func(struct timer_list *t) {
> struct lpuart_port *sport = from_timer(sport, t, lpuart_timer);
> + enum dma_status dmastat;
Should be reverse Christmas tree order.
Regards,
Shenwei
> struct dma_chan *chan = sport->dma_rx_chan;
> struct circ_buf *ring = &sport->rx_ring;
> struct dma_tx_state state;
> unsigned long flags;
> int count;
>
> - dmaengine_tx_status(chan, sport->dma_rx_cookie, &state);
> + dmastat = dmaengine_tx_status(chan, sport->dma_rx_cookie, &state);
> + if (dmastat == DMA_ERROR) {
> + dev_err(sport->port.dev, "Rx DMA transfer failed!\n");
> + return;
> + }
> +
> ring->head = sport->rx_sgl.length - state.residue;
> count = CIRC_CNT(ring->head, ring->tail, sport->rx_sgl.length);
>
> --
> 2.17.1
