usb: host: Drop resume calls on {e,o}hci_platform_suspend()

[PATCH 0/2] usb: host: Drop resume calls on {e,o}hci_platform_suspend()

Posted by Biju 1 week, 4 days ago

From: Biju Das <biju.das.jz@bp.renesas.com>

As per the suspend_devices_and_enter() [1], if .suspend() fails, it invoke
the .resume() callback. This patch series drops redundant resume() from
{e,o}hci_platform_suspend()

[1]
https://elixir.bootlin.com/linux/v6.18-rc7/source/kernel/power/suspend.c#L519

Biju Das (2):
  usb: host: ehci-platform: Drop ehci_resume from
    ehci_platform_suspend()
  usb: host: ohci-platform: Drop ohci_resume from
    ohci_platform_suspend()

 drivers/usb/host/ehci-platform.c | 13 +------------
 drivers/usb/host/ohci-platform.c | 10 +---------
 2 files changed, 2 insertions(+), 21 deletions(-)

-- 
2.43.0

Re: [PATCH 0/2] usb: host: Drop resume calls on {e,o}hci_platform_suspend()

Posted by Alan Stern 1 week, 4 days ago

On Sun, Dec 07, 2025 at 12:47:25PM +0000, Biju wrote:
> From: Biju Das <biju.das.jz@bp.renesas.com>
> 
> As per the suspend_devices_and_enter() [1], if .suspend() fails, it invoke
> the .resume() callback.

Quite wrong.  If .suspend() fails, the core assumes the device is still 
at full power.  It does not try to resume the device.

> This patch series drops redundant resume() from
> {e,o}hci_platform_suspend()

These resume() calls are not redundant and they should not be dropped.

> [1]
> https://elixir.bootlin.com/linux/v6.18-rc7/source/kernel/power/suspend.c#L519

The message on this line has no bearing on what you are doing.  It 
merely says "Some devices failed to suspend, or early wake event 
detected".  There's nothing about invoking the .resume() callback.

Alan Stern