drivers/tty/serial/8250/8250_omap.c | 2 ++ 1 file changed, 2 insertions(+)
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@ti.com>
---
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);
+
return pinctrl_select_state(priv->pinctrl, priv->pinctrl_wakeup);
}
---
base-commit: f8f9c1f4d0c7a64600e2ca312dec824a0bc2f1da
change-id: 20251230-uart-wakeup-00faeac7c994
Best regards,
--
Kendall Willis <k-willis@ti.com>
On Tue, Dec 30, 2025 at 03:24:51PM -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@ti.com> > --- > 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 How am I to pull any of this into the mainline kernel tree? If this is dependant on those out-of-tree stuff, there's no need for me to take this now, please submit this all together properly. thanks, greg k-h
On 1/16/26 07:16, Greg Kroah-Hartman wrote: > On Tue, Dec 30, 2025 at 03:24:51PM -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@ti.com> >> --- >> 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 > > How am I to pull any of this into the mainline kernel tree? If this is > dependant on those out-of-tree stuff, there's no need for me to take > this now, please submit this all together properly. This patch has no dependencies on the listed series. I listed them so that there was a full picture of the feature implementation. The "pmdomain: ti_sci: handle wakeup constraint for out-of-band wakeup" patch has been merged already [1]. The "arm64: dts: ti: k3-am62: Support Main UART wakeup" series is posted [2] and has a dependency on this patch. Sorry for the confusion with the GitHub links, in the future I either won't add them or will add lore links instead. [1] https://lore.kernel.org/all/20251230-pmdomain-v1-1-3a009d1ff72e@ti.com/ [2] https://lore.kernel.org/all/20260106-b4-uart-daisy-chain-dts-v3-0-398a66258f2c@ti.com/ Best, Kendall Willis <k-willis@ti.com> > > thanks, > > greg k-h
On Fri, Jan 16, 2026 at 09:37:44AM -0600, Kendall Willis wrote: > On 1/16/26 07:16, Greg Kroah-Hartman wrote: > > On Tue, Dec 30, 2025 at 03:24:51PM -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@ti.com> > > > --- > > > 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 > > > > How am I to pull any of this into the mainline kernel tree? If this is > > dependant on those out-of-tree stuff, there's no need for me to take > > this now, please submit this all together properly. > > This patch has no dependencies on the listed series. I listed them so that > there was a full picture of the feature implementation. The "pmdomain: > ti_sci: handle wakeup constraint for out-of-band wakeup" patch has been > merged already [1]. The "arm64: dts: ti: k3-am62: Support Main UART wakeup" > series is posted [2] and has a dependency on this patch. Sorry for the > confusion with the GitHub links, in the future I either won't add them or > will add lore links instead. > > [1] https://lore.kernel.org/all/20251230-pmdomain-v1-1-3a009d1ff72e@ti.com/ > [2] https://lore.kernel.org/all/20260106-b4-uart-daisy-chain-dts-v3-0-398a66258f2c@ti.com/ > > Best, > Kendall Willis <k-willis@ti.com> Great, can you resend this then without that information to confuse me? :) thanks, greg k-h
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@ti.com> > --- > 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@ti.com> -- Best regards, Dhruva Gole Texas Instruments Incorporated
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