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

Commit 8006479c9b 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: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Anssi Hannula
2008-10-04 14:44:06 +02:00
committed by Jiri Kosina
parent dded364bf4
commit f129ea6d1e
4 changed files with 37 additions and 7 deletions

View File

@@ -388,6 +388,12 @@ struct hid_report_enum {
struct hid_control_fifo {
unsigned char dir;
struct hid_report *report;
char *raw_report;
};
struct hid_output_fifo {
struct hid_report *report;
char *raw_report;
};
#define HID_CLAIMED_INPUT 1