[Public] > -----Original Message----- > From: Oliver Neukum <oneukum@xxxxxxxx> > Sent: Tuesday, February 28, 2023 03:03 > To: Limonciello, Mario <Mario.Limonciello@xxxxxxx>; Oliver Neukum > <oneukum@xxxxxxxx>; Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>; Michael > Wu <michael@xxxxxxxxxxxxxxxxx> > Cc: jikos@xxxxxxxxxx; benjamin.tissoires@xxxxxxxxxx; linux- > usb@xxxxxxxxxxxxxxx; linux-input@xxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; Gong, Richard <Richard.Gong@xxxxxxx> > Subject: Re: [PATCH] HID: usbhid: enable remote wakeup for mice > > On 23.02.23 20:41, Limonciello, Mario wrote: > > Hi, > > >> As a system wakeup source a mouse that generates events when > >> it is moved, however, would make the system unsuspendable, whenever > >> even > >> a bit of vibration is acting on the system. > >> And as S4 is used in many setups to prevent an uncontrolled shutdown > >> at low power, this must work. > > > > At least in my version of the series, this is part of the reason that it was > > only intended to be used with s2idle. > > Yes, that is sensible. If these patches are to be taken at all, that will > be a necessary condition to meet. But it is not sufficient. Ack. > > > The kernel driver is well aware of what power state you're in the suspend > > callback (pm_suspend_target_state). > > > > What about if we agreed to treat this one special by examining that? > > > > If the sysfs is set to "enabled" > > If user space needs to manipulate sysfs at all, we can have user space > tell kernel space exactly what to do. Hence I see no point in > conditional interpretations values in sysfs at that point. > > We are discussing the kernel's default here. Right, I was meaning if the kernel defaulted to enabled or if userspace changed it to enabled to follow this behavior. > > > * During suspend if your target is s2idle -> program it > > * During suspend if your target is mem -> disable it > > * During suspend if your target is hibernate -> disable it > > To my mind these defaults make sense. > However, do they make much more sense than what we are doing now? If you're talking about purely "policy default", I think it makes more sense. Userspace can still change it, and it better aligns with what Windows does out of the box. > > > With that type of policy on how to handle the suspend call in place > > perhaps we could set it to enabled by default? > > It pains me to say, but I am afraid in that regard the only > decision that will not cause ugly surprises is to follow Windows. > Yet, what is wrong about the current defaults? I still keep getting inquiries about this where teams that work on the same hardware for Windows and Linux complain about this difference during their testing. I keep educating them to change it in sysfs (or to use a udev rule), but you have to question if you keep getting something asked about policy over and over if it's actually the right policy.
