Linux 6.1 Change Aims To Auto-Detect Logitech HID++ High Resolution Scrolling Support

Currently Linux's Logitech HID++ driver "hid-logitech-hidpp" relies on a static list of device quirks for indicating which Logitech mice support high resolution scrolling. With the upcoming Linux 6.1 kernel, the plan is to change that list of devices/quirks and to automatically determine if a device supports high resolution scrolling.

The current approach of effectively white-listing devices that support HID++ high resolution scrolling is susceptible to a poor user experience in particular for new Logitech devices that have yet to be added to the quirk list, especially with Logitech not maintaining the list but is a matter left up to the open-source community. Thankfully developer Bastien Nocera has taken to improving the hid-logitech-hidpp driver to actually detect the high resolution scrolling support and thus allowing the list to be eliminated.

This patch is queued in HID's for-next branch ahead of the Linux 6.1 merge window opening shortly.

This change will detect whether HID++ 1.0 hi-res scroll, HID++ 2.0 hi-res scroll or HID++ 2.0 hi-res scroll wheel is supported, and enable the feature without the need for quirks.

Tested on a Logitech M705 mouse that was unsupported before this change.

Users can look at logitech-hidpp lines in dmesg for messages such as "Detected HID++ 2.0 hi-res scroll wheel" in determining whether your Linux mouse is making use of high resolution scrolling / high resolution scroll wheel support. This change will hopefully see a lot more Logitech devices now supporting this feature under Linux that previously weren't part of the device quirk list. This is more useful with a modern Linux desktop now that Wayland supports high resolution scroll events and there's been libinput support since earlier this year.

It's also with Linux 6.1 that the driver is now trying to enable HID++ for all Logitech Bluetooth devices.