On Fri, Jul 08, 2022 at 02:58:00PM -0500, shenwei.wang@xxxxxxx wrote:
> The LPUART hardware doesn't zero out the parity bit on the received
> characters. This behavior won't impact the use cases of CS8 because
> the parity bit is the 9th bit which is not currently used by software.
> But the parity bit for CS7 must be zeroed out by software in order to
> get the correct raw data.
>
> Signed-off-by: Shenwei Wang <shenwei.wang@xxxxxxx>
> ---
> changes in v1
> - fix the code indent and whitespace issue;
Normal patches start numbering at v1 :)
> drivers/tty/serial/fsl_lpuart.c | 26 ++++++++++++++++++++++++--
> 1 file changed, 24 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
> index 8fe0494d4057b..a8f59fb27c825 100644
> --- a/drivers/tty/serial/fsl_lpuart.c
> +++ b/drivers/tty/serial/fsl_lpuart.c
> @@ -274,6 +274,8 @@ struct lpuart_port {
> int rx_dma_rng_buf_len;
> unsigned int dma_tx_nents;
> wait_queue_head_t dma_wait;
> + bool is_cs7; /* Set to true when character size is 7 */
> + /* and the parity is enabled */
> };
>
> struct lpuart_soc_data {
> @@ -1022,6 +1024,9 @@ static void lpuart32_rxint(struct lpuart_port *sport)
> flg = TTY_OVERRUN;
> }
>
> + if (sport->is_cs7)
> + rx &= 0x7F;
> +
> if (tty_insert_flip_char(port, rx, flg) == 0)
> sport->port.icount.buf_overrun++;
> }
> @@ -1107,6 +1112,17 @@ static void lpuart_handle_sysrq(struct lpuart_port *sport)
> }
> }
>
> +static inline int lpuart_tty_insert_flip_string(struct tty_port *port,
> + unsigned char *chars, size_t size, bool is_cs7)
Why inline? Don't do that unless it is measurable with and without it,
good compilers will guess this correctly.
thanks,
greg k-h
