ab19c1ddaa
commit ff479731c3859609530416a18ddb3db5db019b66 upstream. The HID descriptors for most Wacom devices oddly declare the serial number and other related fields as signed integers. When these numbers are ingested by the HID subsystem, they are automatically sign-extended into 32-bit integers. We treat the fields as unsigned elsewhere in the kernel and userspace, however, so this sign-extension causes problems. In particular, the sign-extended tool ID sent to userspace as ABS_MISC does not properly match unsigned IDs used by xf86-input-wacom and libwacom. We introduce a function 'wacom_s32tou' that can undo the automatic sign extension performed by 'hid_snto32'. We call this function when processing the serial number and related fields to ensure that we are dealing with and reporting the unsigned form. We opt to use this method rather than adding a descriptor fixup in 'wacom_hid_usage_quirk' since it should be more robust in the face of future devices. Ref: https://github.com/linuxwacom/input-wacom/issues/134 Fixes: f85c9dc678 ("HID: wacom: generic: Support tool ID and additional tool types") CC: <stable@vger.kernel.org> # v4.10+ Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Aaron Armstrong Skomra <aaron.skomra@wacom.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.