[PATCH v4 0/5] pmdomain: core: Introduce device_set_out_band_wakeup and use it in usb

Peng Fan
2025-09-22T02:21:26Z

To i.MX95, USB2 and USB3 are in HSIOMIX domain, but there is always on logic
to make USB2 and USB3 has wakeup capability when HSIOMIX power domain
is in off state. So when in system-suspend state, USB2/USB3 could wakeup
the system even the USB2/USB3 HSIOMIX power domain is turned off. This
means USB2/USB3 has out-of-band wakeup capability to wakeup system from
suspended state.

Without this patchset, if USB2/USB3 are configured with wakeup enabled,
the HSIOMIX power domain will not be turned off. This leads to more
power consumed in system suspend state.

This patchset introduces device_set_out_band_wakeup and
device_out_band_wakeup two APIs to set out-of-band and query the flag.
In genpd_finish_suspend, there is a check, if out-of-band is set,
it will continue to turn off the power domain. In genpd resume flow,
there is a similar check to turn on the power domain.

Patch 1,2 introduces device_set_out_band_wakeup and
device_out_band_wakeup
Patch 3 and 4 are drivers changes to use device_out_band_wakeup

More old discussions:
https://lore.kernel.org/linux-pm/20250311083239.3336439-1-peng.fan@oss.nxp.com/

This is pick up of [1]
This V2 patchset
- includes usb driver changes to give people a full picture on how it is used.
- Rebased next-20250729 to resolve conflicts

[1]https://lore.kernel.org/linux-pm/20250311083239.3336439-1-peng.fan@oss.nxp.com/

Changes in v4:
- Split device_set_out_band_wakeup API and pmdomain changes into patch 1
and 2 and clear the flag in device_prepare (from Ulf)
- Add R-b in patch 2
- Move the call of device_set_out_band_wakeup to system suspend
callback in patch 3 and 4. (from Ulf)
- For patch 3,4, I still keep the Tags, since compared with V3, it is quite
small changes.
- Link to v3: https://lore.kernel.org/r/20250902-pm-v3-0-ffadbb454cdc@nxp.com

Changes in v3:
- Add a new patch from Xu Yang to detach power domain for ci hdrc
- Add A-b for patch 4
- Link to v2: https://lore.kernel.org/r/20250801-pm-v2-0-97c8fb2a433c@nxp.com

Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
Peng Fan (4):
PM: wakeup: Add out-of-band system wakeup support for devices
PM: domains: Allow power-off for out-of-band wakeup-capable devices
usb: chipidea: ci_hdrc_imx: Set out of band wakeup for i.MX95
usb: dwc3: imx8mp: Set out of band wakeup for i.MX95

Xu Yang (1):
usb: chipidea: core: detach power domain for ci_hdrc platform device

drivers/base/power/main.c | 1 +
drivers/pmdomain/core.c | 6 ++++--
drivers/usb/chipidea/ci_hdrc_imx.c | 11 ++++++++++-
drivers/usb/chipidea/core.c | 3 +++
drivers/usb/dwc3/dwc3-imx8mp.c | 9 +++++++--
include/linux/pm.h | 1 +
include/linux/pm_wakeup.h | 17 +++++++++++++++++
include/linux/usb/chipidea.h | 1 +
8 files changed, 44 insertions(+), 5 deletions(-)
---
base-commit: 8f7f8b1b3f4c613dd886f53f768f82816b41eaa3
change-id: 20250919-pm-v4-1879568de500

Best regards,
--
Peng Fan <peng.fan@nxp.com>