[PATCH] pmdomain: ti_sci: handle wakeup constraint for out-of-band wakeup

[Ulf Hansson]

On Tue, 30 Dec 2025 at 22:37, Kendall Willis <k-willis at ti.com> wrote:
>
> For devices capable of out-of-band system wakeups via I/O daisy chaining,
> prevent sending wakeup constraints to the PM co-processor. This allows
> the system to enter deeper low power modes, as the device is not marked
> as requiring power.
>
> Replaces the logic from commit b06bc4727991 ("pmdomain: ti_sci: handle
> wake IRQs for IO daisy chain wakeups") since checking out-of-band wakeup
> will cover the same functionality.
>
> Detect out-of-band wakeup in the suspend path, and if it exists, skip
> sending the constraint.
>
> Signed-off-by: Kendall Willis <k-willis at ti.com>

Applied for next, thanks!

Kind regards
Uffe

> ---
> Implementation
> --------------
> This patch is intended to be implemented along with the following
> series. This patch has no dependencies on any of the other series:
>
> 1. "pmdomain: ti_sci: handle wakeup constraint for out-of-band wakeup"
>    (this patch): Skips setting constraints for wakeup sources that have
>    out-of-band wakeup capability.
>    https://github.com/kwillis01/linux/commits/v6.19/uart-daisy-chain/pmdomain
>
> 2. "serial: 8250: omap: set out-of-band wakeup if wakeup pinctrl exists":
>    Implements out-of-band wakeup from the UARTs for TI K3 SoCs
>    https://github.com/kwillis01/linux/tree/v6.19/uart-daisy-chain/uart-wakeup
>
> 3. "arm64: dts: ti: k3-am62: Support Main UART wakeup": Implements the
>    functionality to wakeup the system from the Main UART
>    https://github.com/kwillis01/linux/tree/b4/uart-daisy-chain-dts

FWIW:
I had a quick look at 2) and 3), both seem fine to me.


>
> Testing
> -------
> Tested on a AM62P SK EVM board with all series and dependencies
> implemented. Suspend/resume verified with the Main UART wakeup source
> by entering a keypress on the console.
>
> This github branch has all the necessary patches to test the series
> using v6.19-rc1:
> https://github.com/kwillis01/linux/tree/v6.19/uart-daisy-chain/all
> ---
>  drivers/pmdomain/ti/ti_sci_pm_domains.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pmdomain/ti/ti_sci_pm_domains.c b/drivers/pmdomain/ti/ti_sci_pm_domains.c
> index e5d1934f78d9ee0a02eb05aa1301cd5a59e134d6..18d33bc35dee1b3bf6107af1e414db377d515199 100644
> --- a/drivers/pmdomain/ti/ti_sci_pm_domains.c
> +++ b/drivers/pmdomain/ti/ti_sci_pm_domains.c
> @@ -91,8 +91,9 @@ static inline void ti_sci_pd_set_wkup_constraint(struct device *dev)
>                  * If device can wakeup using IO daisy chain wakeups,
>                  * we do not want to set a constraint.
>                  */
> -               if (dev->power.wakeirq) {
> -                       dev_dbg(dev, "%s: has wake IRQ, not setting constraints\n", __func__);
> +               if (device_out_band_wakeup(dev)) {
> +                       dev_dbg(dev, "%s: has out of band wakeup, not setting constraints\n", \
> +                                       __func__);
>                         return;
>                 }
>
>
> ---
> base-commit: f8f9c1f4d0c7a64600e2ca312dec824a0bc2f1da
> change-id: 20251230-pmdomain-e71bed9b40f8
>
> Best regards,
> --
> Kendall Willis <k-willis at ti.com>
>