HID: wacom: Call 'wacom_query_tablet_data' only after 'hid_hw_start'
When connecting the Cintiq Companion 2 as an external tablet (i.e., using it in "hybrid" mode) it has been seen to cause the kernel of the machine it is connected to to Oops. The cause has been traced to us attempting to switch the tablet's mode prior to actually starting HID device (resulting in the eventual dereference of the uninitialized control URB). Commit 3b164a00 moved the mode switch from occuring post-start to occurring pre-start. The change was not seen to cause issues largely due to the fact that most devices mode switch with 'hid_hw_raw_request' (which is safe to call prior to start) rather than 'hid_hw_request'. Moving the call back to its original location resolves the issue, but causes some touch-only Bamboo tablets (e.g. 056a:00d0) to stop working. The affected tablets require us to perform a mode switch on their vestigial pen interface prior ignoring with -ENODEV, meaning that the code which is responsible for doing the ignoring has to move as well. Signed-off-by:Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by:
Ping Cheng <pingc@wacom.com> Signed-off-by:
Jiri Kosina <jkosina@suse.cz>
parent
8253d42b
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