• Jason Gerecke's avatar
    HID: wacom: Discover device_type from HID descriptor for all devices · 042628ab
    Jason Gerecke authored
    Currently, we assume a device_type of BTN_TOOL_PEN before scanning the
    HID descriptor and then change the device_type if what we discover
    proves that assumption wrong. This way of doing things makes it more
    difficult to figure out if a device (particularly a HID_GENERIC device)
    actually does tablet/touch input or is something completley different.
    
    This patch leaves device_type at its initial value of 0 and then calls
    'wacom_parse_hid' for every device (not just those that have touch).
    As we map the usages, we can set the device_type as before. After we're
    finished, we can then check if the value is still zero and do whatever
    is most appropriate.
    
    Detecting the pen can be a little tricky on most Wacom devices because
    the descriptors describe opaque blobs. Fortunately, older Wacom tablets
    have the HID_DG_DIGITIZER usage on the pen's application collection and
    newer tablets seem to have a similar vendor-defined usage that we can
    trigger on.
    Signed-off-by: default avatarJason Gerecke <jason.gerecke@wacom.com>
    Reviewed-by: default avatarPing Cheng <pingc@wacom.com>
    Reviewed-by: default avatarBenjamin Tissoires <benjamin.tissoires@redhat.com>
    Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
    042628ab
wacom_sys.c 42.6 KB