On Fri, 2019-06-14 at 15:36 +0200, Benjamin Tissoires wrote: > Hi Wolfgang, > > On Thu, Jun 13, 2019 at 1:49 PM Wolfgang Bauer wrote: > > On Tuesday, 11. Juni 2019, 16:42:37 Benjamin Tissoires wrote: > > > On Tue, Jun 11, 2019 at 2:13 PM Nicolas Saenz Julienne > > > > > > wrote: > > > > NOTE: I CC'd Wolfgang as he's the one who can test this. > > > > > > I'll wait for Wolfram to confirm that the patch works before pushing then. > > > > My name is Wolfgang, not Wolfram... ;-) > > ouch, sorry for that (I am more used to talk to the I2C maintainer apparently) > > > But never mind. > > > > I tested the patch meanwhile on top of kernel 5.2.rc4, where the mouse wheel > > actually worked. > > Actually, I am a little bit lost here. > > The patch mentions a fix of c01908a14bf73, which is in 5.1 final. > So if your mouse works in 5.2.rc4, I am not sure how > HID-a4tech-fix-horizontal-scrolling.patch could break it. > > Could you be slightly more specific in what "works" and what doesn't? Hi Benjamin, First of all here's the descriptor: 0x05, 0x01, /* Usage Page (Desktop), */ 0x09, 0x02, /* Usage (Mouse), */ 0xA1, 0x01, /* Collection (Application), */ 0x09, 0x01, /* Usage (Pointer), */ 0xA1, 0x00, /* Collection (Physical), */ 0x05, 0x09, /* Usage Page (Button), */ 0x19, 0x01, /* Usage Minimum (01h), */ 0x29, 0x08, /* Usage Maximum (08h), */ 0x15, 0x00, /* Logical Minimum (0), */ 0x25, 0x01, /* Logical Maximum (1), */ 0x75, 0x01, /* Report Size (1), */ 0x95, 0x08, /* Report Count (8), */ 0x81, 0x02, /* Input (Variable), */ 0x05, 0x01, /* Usage Page (Desktop), */ 0x09, 0x30, /* Usage (X), */ 0x09, 0x31, /* Usage (Y), */ 0x09, 0x38, /* Usage (Wheel), */ 0x09, 0xB8, /* Usage (B8h), */ 0x15, 0x81, /* Logical Minimum (-127), */ 0x25, 0x7F, /* Logical Maximum (127), */ 0x75, 0x08, /* Report Size (8), */ 0x95, 0x04, /* Report Count (4), */ 0x81, 0x06, /* Input (Variable, Relative), */ 0xC0, /* End Collection, */ 0xC0 /* End Collection Sorry for the confusion, I'll try to explain the situation: In v5.2-rc4 without "HID-a4tech-fix-horizontal-scrolling.patch" the vertical wheel works out of luck as it's mapped to REL_WHEEL_HIGH_RES, which hid-a4tech ignores and lets hid-input process, the horizontal wheel is broken. On top of that Usage(0xB8) is also ignored by both hid-a4tech and hid-input as it isn't mapped to anything. There are two distinct bugs here: - High resolution wheel processing in hid-a4tech not being implemented, breaking horizontal wheels. - hid-a4tech not taking care of Usage(0xB8) correctly as it depended on it being mapped to "Rel.Misc". That behaviour changed in v5.1 with "HID: input: add mapping for "Toggle Display" key". Once high resolution wheel reports are fixed and handled in hid-a4tech's custom event, the mouse breaks as it's the processing of Usage(0xB8) that triggers the input_events, which is being ignored. You'll probably ask how come we didn't see this when "HID-a4tech-fix-horizontal-scrolling.patch" was merged. It's due to the fact it was tested on an older kernel, v5.0.15, that didn't contain "HID: input: add mapping for "Toggle Display" key"[1]. So that's why I added that specific fix tag. For LTS kernels, it is possible that "Toggle Display" support was back-ported but not the high resolution wheels support. Hope it made things more clear. Regards, Nicolas [1] https://lkml.kernel.org/lkml/nycvar.YFH.7.76.1906010028440.1962@cbobk.fhfr.pm/T/ > > Do we have the report descriptors available somewhere? > And if not, could you run hid-recorder from > https://gitlab.freedesktop.org/libevdev/hid-tools and attach the logs > when you move the horizontal wheel? > > Cheers, > Benjamin > > > As the patch didn't apply cleanly (it's obviously based upon > > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=abf82e8f7e9af40a49e3d905187c662a43c96c8f , called > > "HID- > > a4tech-fix-horizontal-scrolling.patch" below), I added that patch as well. > > > > My results: > > kernel 5.2.rc4 works > > kernel 5.2.rc4 + HID-a4tech-fix-horizontal-scrolling.patch is broken > > kernel 5.2.rc4 + HID-a4tech-fix-horizontal-scrolling.patch + > > HID-input-fix-a4tech-horizontal-wheel-custom-usage.patch (i.e. this patch) > > works again > > > > kernel 5.2.rc4 + HID-input-fix-a4tech-horizontal-wheel-custom-usage.patch > > works as well. > > > > So AFAICT this patch seems to be fine. > > > > For completeness, this is my mouse as listed by lsusb: > > Bus 003 Device 002: ID 09da:000a A4Tech Co., Ltd. Optical Mouse Opto 510D / > > OP-620D > > > > Kind Regards, > > Wolfgang > >