On Wed, 17 Jan 2024, Doug Anderson wrote: > > There's a Cirque touchpad that wakes system up without anything > > touched the touchpad. The input report is empty when this happens. The > > reason is stated in HID over I2C spec, 7.2.8.2: "If the DEVICE wishes > > to wake the HOST from its low power state, it can issue a wake by > > asserting the interrupt." > > > > This is fine if OS can put system back to suspend by identifying input > > wakeup count stays the same on resume, like Chrome OS Dark Resume [0]. > > But for regular distro such policy is lacking. > > > > Though the change doesn't bring any impact on power consumption for > > touchpad is minimal, other i2c-hid device may depends on SLEEP control > > power. So use a quirk to limit the change scope. > > > > [0] https://chromium.googlesource.com/chromiumos/platform2/+/HEAD/power_manager/docs/dark_resume.md > > > > Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> > > --- > > v2: > > - Use quirk instead of applying the change universally. > > > > drivers/hid/hid-ids.h | 3 +++ > > drivers/hid/i2c-hid/i2c-hid-core.c | 6 +++++- > > 2 files changed, 8 insertions(+), 1 deletion(-) > > This seems OK to me. As per my repy to v1, it doesn't feel fully > explained what's going on. Why does it only wake the system without > touches if you put it to sleep first? Is it truly a hardware quirk with > the Cirque touchpad or is it a bug on the board you have it hooked up > to? In any case, perhaps it doesn't matter since you said you measured > power here and, on this touchpad it doesn't seem to save significant > extra power to go into sleep mode. ...so I guess I'd be OK w/ > > Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx> Applied, thanks. -- Jiri Kosina SUSE Labs
