On Tue, 29 May 2018, Ben Chan wrote: > According to [1] and also seemingly agreed by [2], the Scan Time usage > (0x0D 0x56) is a report level usage, not a contact level usage. > > However, the hid-multitouch driver currently includes HID_DG_SCANTIME > when calculating `td->last_slot_field', which may lead to > mt_complete_slot() being prematurely called in certain cases (e.g. when > each touch input report includes more than one contact and the Scan Time > usage appears before any contact logical collection). > > This patch fixes the issue by skipping mt_store_field() on > HID_DG_SCANTIME, similar to how HID_DG_CONTACTCOUNT and > HID_DG_CONTACTMAX are handled. > > [1] > https://docs.microsoft.com/en-us/windows-hardware/design/component-guidelines/windows-precision-touchpad-required-hid-top-level-collections#windows-precision-touchpad-input-reports > [2] https://patchwork.kernel.org/patch/1742181/ > > Fixes: 29cc309d8bf19 ("HID: hid-multitouch: forward MSC_TIMESTAMP") > Signed-off-by: Ben Chan <[email protected]>
Applied, thanks Ben. -- Jiri Kosina SUSE Labs
