[PATCH] HID: wacom: Fix deadlock on proximity in events with the Intuos Draw
From: Lyude <hidden>
Date: 2015-12-30 17:08:52
Also in:
lkml
Subsystem:
hid core layer, hid wacom driver, the rest · Maintainers:
Jiri Kosina, Benjamin Tissoires, Ping Cheng, Jason Gerecke, Linus Torvalds
Unfortunately, when we have an Intuos Draw connected using a USB connection, wacom's IRQ handler will be called while the lock for the usbhid driver is held by hid_ctrl. This means when we try to schedule a new proximity event in wacom_intuos_schedule_prox_event() by calling hid_hw_request(), we'll try to take the lock a second time which deadlocks the system. This patch fixes that behavior by initializing a worker when we have a INTUOSHT2 device connected, and using that worker to schedule the proximity event instead. Signed-off-by: Lyude <redacted> --- drivers/hid/wacom_wac.c | 9 +++++++-- drivers/hid/wacom_wac.h | 1 + 2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c
index 01a4f05..b59ded6 100644
--- a/drivers/hid/wacom_wac.c
+++ b/drivers/hid/wacom_wac.c@@ -433,8 +433,10 @@ exit: return retval; } -static void wacom_intuos_schedule_prox_event(struct wacom_wac *wacom_wac) +static void wacom_intuos_schedule_prox_event(struct work_struct *work) { + struct wacom_wac *wacom_wac = + container_of(work, struct wacom_wac, intuos_prox_event_worker); struct wacom *wacom = container_of(wacom_wac, struct wacom, wacom_wac); struct hid_report *r; struct hid_report_enum *re;
@@ -624,7 +626,7 @@ static int wacom_intuos_inout(struct wacom_wac *wacom) /* don't report other events if we don't know the ID */ if (!wacom->id[idx]) { /* but reschedule a read of the current tool */ - wacom_intuos_schedule_prox_event(wacom); + schedule_work(&wacom->intuos_prox_event_worker); return 1; }
@@ -2675,6 +2677,9 @@ int wacom_setup_pen_input_capabilities(struct input_dev *input_dev, if (features->type == INTUOSHT2) { wacom_setup_basic_pro_pen(wacom_wac); + + INIT_WORK(&wacom_wac->intuos_prox_event_worker, + wacom_intuos_schedule_prox_event); } else { __clear_bit(ABS_MISC, input_dev->absbit); __set_bit(BTN_TOOL_PEN, input_dev->keybit);
diff --git a/drivers/hid/wacom_wac.h b/drivers/hid/wacom_wac.h
index 877c24a..c24cfdc 100644
--- a/drivers/hid/wacom_wac.h
+++ b/drivers/hid/wacom_wac.h@@ -237,6 +237,7 @@ struct wacom_wac { int ps_connected; u8 bt_features; u8 bt_high_speed; + struct work_struct intuos_prox_event_worker; struct hid_data hid_data; };
--
2.5.0