Hi Ulrich,
On Tue, Sep 19, 2017 at 5:44 PM, Ulrich Hecht
<ulrich.hecht+renesas@xxxxxxxxx> wrote:
> HSCIF has facilities that allow changing the timeout after which an RX
> interrupt is triggered even if the FIFO is not filled. This patch allows
> changing the default (15 bits of silence) using the existing sysfs
> attribute "rx_fifo_timeout".
>
> Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@xxxxxxxxx>
Thanks for your patch!
> --- a/drivers/tty/serial/sh-sci.c
> +++ b/drivers/tty/serial/sh-sci.c
> @@ -152,6 +152,7 @@ struct sci_port {
> int rx_trigger;
> struct timer_list rx_fifo_timer;
> int rx_fifo_timeout;
> + u16 hscif_tot;
Shouldn't this field be reset to zero in sci_init_single(), like
rx_fifo_timeout?
> @@ -1107,8 +1108,14 @@ static ssize_t rx_fifo_timeout_show(struct device *dev,
> {
> struct uart_port *port = dev_get_drvdata(dev);
> struct sci_port *sci = to_sci_port(port);
> + u16 v;
int, to preserve all bits from rx_fifo_timeout.
>
> - return sprintf(buf, "%d\n", sci->rx_fifo_timeout);
> + if (port->type == PORT_HSCIF)
> + v = sci->hscif_tot >> HSSCR_TOT_SHIFT;
> + else
> + v = sci->rx_fifo_timeout;
> +
> + return sprintf(buf, "%d\n", v);
> }
> @@ -1124,11 +1131,19 @@ static ssize_t rx_fifo_timeout_store(struct device *dev,
> ret = kstrtol(buf, 0, &r);
> if (ret)
> return ret;
> - sci->rx_fifo_timeout = r;
> - scif_set_rtrg(port, 1);
> - if (r > 0)
> - setup_timer(&sci->rx_fifo_timer, rx_fifo_timer_fn,
> - (unsigned long)sci);
> +
> + if (port->type == PORT_HSCIF) {
> + if (r < 0 || r > 3)
> + return -EINVAL;
> + sci->hscif_tot = r << HSSCR_TOT_SHIFT;
> + } else {
> + sci->rx_fifo_timeout = r;
> + scif_set_rtrg(port, 1);
> + if (r > 0)
> + setup_timer(&sci->rx_fifo_timer, rx_fifo_timer_fn,
> + (unsigned long)sci);
> + }
So this sysfs parameter uses slightly different units depending on serial port
type (HSCIF is in 15 Elementary Time Units aka 1.5 frames, SCIF[AB] is in
frames). Do we care?
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
--
To unsubscribe from this list: send the line "unsubscribe linux-serial" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
