Skip to content
Commit f129ea6d authored by Anssi Hannula's avatar Anssi Hannula Committed by Jiri Kosina
Browse files

HID: fix a lockup regression when using force feedback on a PID device

Commit 8006479c

 introduced a spinlock in
input_dev->event_lock, which is locked when handling input events.
However, the hid-pidff driver sleeps when handling events as it waits for
reports being sent to the device before changing the report contents
again.
This causes a system lockup when trying to use force feedback with a PID
device, a regression introduced in 2.6.24 and 2.6.23.15.

Fix it by extracting the raw report data from struct hid_report
immediately when hid_submit_report() is called, therefore allowing
drivers to change the contents of struct hid_report immediately without
affecting the already-queued transfer.

In hid-pidff, re-add the removed usbhid_wait_io() to
pidff_erase_effect() instead, to prevent a full report queue from causing
the submission to fail, thus not freeing up device memory.
pidff_erase_effect() is not called while dev->event_lock is held.

Signed-off-by: default avatarAnssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
parent dded364b
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment