Re: [PATCH] mailbox: cix: Add IRQF_NO_SUSPEND to mailbox interrupt

[Jassi Brar]

On Mon, Feb 9, 2026 at 2:34 AM Dylan Wu <fredwudi0305@xxxxxxxxx> wrote:
>
> During the system suspend process, device interrupts are masked in the
> noirq phase. However, SCMI often needs to exchange final messages with the
> firmware to complete the power-down transition. Without the IRQF_NO_SUSPEND
> flag, the mailbox ISR cannot run during this late stage, leading to SCMI
> communication timeouts and error messages like "SCMI protocol wait for
> resp timeout" during suspend.
>
> Add the IRQF_NO_SUSPEND flag to the interrupt request to ensure the mailbox
> can continue to handle responses during the noirq stages of suspend and
> resume, thereby ensuring a reliable power state transition.
>
> Signed-off-by: Dylan Wu <fredwudi0305@xxxxxxxxx>
> ---
>  drivers/mailbox/cix-mailbox.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mailbox/cix-mailbox.c b/drivers/mailbox/cix-mailbox.c
> index 5bb1416c26a5..5e27c2bf3492 100644
> --- a/drivers/mailbox/cix-mailbox.c
> +++ b/drivers/mailbox/cix-mailbox.c
> @@ -405,7 +405,7 @@ static int cix_mbox_startup(struct mbox_chan *chan)
>         int index = cp->index, ret;
>         u32 val;
>
> -       ret = request_irq(priv->irq, cix_mbox_isr, 0,
> +       ret = request_irq(priv->irq, cix_mbox_isr, IRQF_NO_SUSPEND,
>                           dev_name(priv->dev), chan);
>         if (ret) {
>                 dev_err(priv->dev, "Unable to acquire IRQ %d\n", priv->irq);
> --
> 2.52.0
>
Applied to mailbox/for-next
Thanks
Jassi