Hi Valentin,
On Tue, Apr 19, 2022 at 10:54 AM Valentin Caron
<valentin.caron@xxxxxxxxxxx> wrote:
> Rework stm32_usart_console_putchar() function in order to anticipate
> the case where the character can never be sent.
>
> Signed-off-by: Valentin Caron <valentin.caron@xxxxxxxxxxx>
Thanks for your patch!
> --- a/drivers/tty/serial/stm32-usart.c
> +++ b/drivers/tty/serial/stm32-usart.c
> @@ -1640,10 +1640,16 @@ static void stm32_usart_console_putchar(struct uart_port *port, unsigned char ch
> {
> struct stm32_port *stm32_port = to_stm32_port(port);
> const struct stm32_usart_offsets *ofs = &stm32_port->info->ofs;
> + u32 isr;
> + int ret;
>
> - while (!(readl_relaxed(port->membase + ofs->isr) & USART_SR_TXE))
> - cpu_relax();
> -
> + ret = readl_relaxed_poll_timeout_atomic(port->membase + ofs->isr, isr,
> + (isr & USART_SR_TXE), 100,
> + STM32_USART_TIMEOUT_USEC);
> + if (ret != 0) {
> + dev_err(port->dev, "Error while sending data in UART TX : %d\n", ret);
Does it make sense to print this message, i.e. will the user ever see it?
Or is the failure above temporary?
I assume that you have seen this trigger?
> + return;
> + }
> writel_relaxed(ch, port->membase + ofs->tdr);
> }
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
