Re: [PATCH 6/6] i2c: riic: Add support for RZ/T2H SoC

Geert Uytterhoeven
2025-06-06T13:32:10Z

Hi Prabhakar,

On Fri, 30 May 2025 at 16:31, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Add support for the Renesas RZ/T2H (R9A09G077) SoC, which features a
> different interrupt layout for the RIIC controller. Unlike other SoCs
> with individual error interrupts, RZ/T2H uses a combined error interrupt
> (EEI).
>
> Introduce a new IRQ descriptor table for RZ/T2H, along with a custom
> ISR (`riic_eei_isr`) to handle STOP and NACK detection from the shared
> interrupt.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Thanks for your patch!

> --- a/drivers/i2c/busses/i2c-riic.c
> +++ b/drivers/i2c/busses/i2c-riic.c
> @@ -326,6 +327,19 @@ static irqreturn_t riic_stop_isr(int irq, void *data)
> return IRQ_HANDLED;
> }
>
> +static irqreturn_t riic_eei_isr(int irq, void *data)
> +{
> + u8 icsr2 = riic_readb(data, RIIC_ICSR2);
> +
> + if (icsr2 & ICSR2_NACKF)
> + return riic_tend_isr(irq, data);
> +
> + if (icsr2 & ICSR2_STOP)
> + return riic_stop_isr(irq, data);

Just wondering: can both ICSR2_NACKF and ICSR2_STOP be set?
As riic_tend_isr() clears only ICSR2_NACKF, while riic_stop_isr()
clears all bits, the two calls could be chained, if needed.

> +
> + return IRQ_NONE;
> +}
> +
> static u32 riic_func(struct i2c_adapter *adap)
> {
> return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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