Hi Takashi, Thanks for reporting the regression here. On Fri, Mar 18, 2022 at 12:42:31PM +0100, Takashi Iwai wrote: > Hi, > > we received a bug report about the regression of the touchpad on Dell > 7750 laptop, the right touchpad button is disabled on recent kernels: > https://bugzilla.suse.com/show_bug.cgi?id=1197243 > > Note that it's a physical button, not a virtual clickpad button. > > The regression seems introduced by the upstream commit > 37ef4c19b4c659926ce65a7ac709ceaefb211c40 ("Input: clear > BTN_RIGHT/MIDDLE on buttonpads") that was backported to stable 5.16.x > kernel. > > The device is managed by hid-multitouch driver, and the further > investigation revealed that it's rather an incorrectly recognized > buttonpad property; namely, ID_DG_BUTTONTYPE reports it being 0 = > clickable touchpad although it's not. I built a test kernel to ignore > this check and it was confirmed to make the right button working again > by the reporter. > > Is this check really correct in general? Or do we need some > device-specific quirk? A couple of days ago another user with the same laptop (Dell Precision 7550 or 7750) emailed me to report the issue and I sent him a patch for testing. I he confirms that the patch works, I'll send it to the mailing list. I believe that your analysis of the regression is correct and I think that we'd need to add a quirk for the device. In case you want to have a look to the patch, I added it to this libinput [1] report. Thanks, Jose [1] https://gitlab.freedesktop.org/libinput/libinput/-/merge_requests/726#note_1303623
