Re: [PATCH] serial: 8250: omap: set out-of-band wakeup if wakeup pinctrl exists

[Dhruva Gole]

On Dec 30, 2025 at 15:24:51 -0600, Kendall Willis wrote:
> In TI K3 SoCs, I/O daisy chaining is used to allow wakeup from UART when
> the UART controller is off. Set UART device as wakeup capable using
> out-of-band wakeup if the 'wakeup' pinctrl state exists and the device may
> wakeup.
> 
> Signed-off-by: Kendall Willis <k-willis@xxxxxx>
> ---
> 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":
>    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"
>    (this patch): 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
> 
> 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/tty/serial/8250/8250_omap.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
> index 9e49ef48b851bf6cd3b04a77a4d0d7b4e064dc5f..6a5722b722650c1710e79fb76fc1a01cdeccc68f 100644
> --- a/drivers/tty/serial/8250/8250_omap.c
> +++ b/drivers/tty/serial/8250/8250_omap.c
> @@ -1363,6 +1363,8 @@ static int omap8250_select_wakeup_pinctrl(struct device *dev,
>  	if (!device_may_wakeup(dev))
>  		return 0;
>  
> +	device_set_out_band_wakeup(dev);
> +

Reviewed-by: Dhruva Gole <d-gole@xxxxxx>

-- 
Best regards,
Dhruva Gole
Texas Instruments Incorporated