Hi Biju,
On Thu, Mar 16, 2023 at 5:01 PM Biju Das <biju.das.jz@xxxxxxxxxxxxxx> wrote:
> The RZ SCI/ RZ/A1 SCIF has only 4 interrupts. The fourth interrupt
> is transmit end interrupt, so shuffle the interrupts to fix the
> transmit end interrupt handler for these IPs.
>
> Fixes: 392fb8df528b ("serial: sh-sci: Use platform_get_irq_optional() for optional interrupts")
I don't think that's the right bad commit.
> Suggested-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
Thanks for your patch!
> --- a/drivers/tty/serial/sh-sci.c
> +++ b/drivers/tty/serial/sh-sci.c
> @@ -31,6 +31,7 @@
> #include <linux/ioport.h>
> #include <linux/ktime.h>
> #include <linux/major.h>
> +#include <linux/minmax.h>
> #include <linux/module.h>
> #include <linux/mm.h>
> #include <linux/of.h>
> @@ -2841,6 +2842,7 @@ static int sci_init_single(struct platform_device *dev,
> struct uart_port *port = &sci_port->port;
> const struct resource *res;
> unsigned int i;
> + int irq_cnt;
> int ret;
>
> sci_port->cfg = p;
> @@ -2864,6 +2866,14 @@ static int sci_init_single(struct platform_device *dev,
> sci_port->irqs[i] = platform_get_irq(dev, i);
> }
>
> + /*
> + * RZ SCI/ RZ/A1 SCIF has only 4 interrupts. The fourth interrupt
> + * is transmit end interrupt, so shuffle the interrupts.
> + */
> + irq_cnt = platform_irq_count(dev);
> + if (irq_cnt == 4)
> + swap(sci_port->irqs[SCIx_BRI_IRQ], sci_port->irqs[SCIx_TEI_IRQ]);
> +
I think it's simpler to just check if SCIx_TEI_IRQ is missing:
if (sci_port->irqs[SCIx_TEI_IRQ] < 0)
swap(sci_port->irqs[SCIx_BRI_IRQ], sci_port->irqs[SCIx_TEI_IRQ]);
We already rely on "make dtbs_check" to catch invalid combinations
(anything different from 1/4/6 interrupts).
And please move that code below, together with the other checks for
non-existing interrupts.
> /* The SCI generates several interrupts. They can be muxed together or
> * connected to different interrupt lines. In the muxed case only one
> * interrupt resource is specified as there is only one interrupt ID.
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
