The Claw MCU re-sends an unhandled ACK roughly every 2 seconds until it
receives another command. When an ACK arrives with waiting_cmd set to
CLAW_COMMAND_TYPE_NONE, such as after a command is written through
hidraw or once orphan_ack_pending has been cleared without a subsequent
command, the driver currently logs "Got unexpected ACK from MCU,
ignoring" on every re-transmission and never clears the MCU's pending
ACK state.
Schedule a work item that issues a harmless READ_GAMEPAD_MODE query when
an unexpected ACK arrives. Receiving any command causes the MCU to stop
re-sending the pending ACK, eliminating the repeated events and log
spam.
Fixes: a9517958e828 ("HID: hid-msi: Add MSI Claw configuration driver")
Signed-off-by: Kenhou Iijima <redacted>
---
Tested on an MSI Claw 8 AI+ A2VM (0db0:1901, bcdDevice 2.30).
drivers/hid/hid-msi.c | 25 ++++++++++++++++++++++++-
1 file changed, 24 insertions(+), 1 deletion(-)
diff --git a/drivers/hid/hid-msi.c b/drivers/hid/hid-msi.c
index 23d731f700..e52923fcc8 100644
--- a/drivers/hid/hid-msi.c
+++ b/drivers/hid/hid-msi.c
@@ -332,6 +332,7 @@ struct claw_drvdata {
enum claw_profile_ack_pending profile_pending;
struct completion orphan_ack_complete;
struct completion send_cmd_complete;
+ struct work_struct orphan_ack_work;
struct delayed_work cfg_resume;
struct delayed_work cfg_setup;
spinlock_t registration_lock; /* Lock for registration read/write */@@ -532,7 +533,12 @@ static int claw_raw_event(struct claw_drvdata *drvdata, struct hid_report *repor
}
if (drvdata->waiting_cmd == CLAW_COMMAND_TYPE_NONE) {
- dev_warn(&drvdata->hdev->dev, "Got unexpected ACK from MCU, ignoring\n");
+ /*
+ * The MCU re-sends an unhandled ACK roughly every 2 s
+ * until it receives another command. Drain it by
+ * scheduling a harmless query so the ACK storm stops.
+ */
+ schedule_work(&drvdata->orphan_ack_work);
break;
}
@@ -653,6 +659,20 @@ static int claw_hw_output_report(struct hid_device *hdev, u8 index, u8 *data,
return __claw_hw_output_report(hdev, index, data, len, timeout);
}
+static void claw_orphan_ack_drain(struct work_struct *work)
+{
+ struct claw_drvdata *drvdata = container_of(work, struct claw_drvdata,
+ orphan_ack_work);
+
+ /*
+ * A query is enough to make the MCU stop re-sending the pending ACK.
+ * claw_hw_output_report() also waits for any orphan ACK before
+ * sending, so this cannot interleave with a real command sequence.
+ */
+ claw_hw_output_report(drvdata->hdev, CLAW_COMMAND_TYPE_READ_GAMEPAD_MODE,
+ NULL, 0, 25);
+}
+
static int claw_switch_mode(struct hid_device *hdev, enum claw_mode_field field, u8 val)
{
struct claw_drvdata *drvdata = hid_get_drvdata(hdev);@@ -1868,6 +1888,7 @@ static int claw_probe(struct hid_device *hdev, u8 ep)
spin_lock_init(&drvdata->rumble_lock);
init_completion(&drvdata->orphan_ack_complete);
init_completion(&drvdata->send_cmd_complete);
+ INIT_WORK(&drvdata->orphan_ack_work, &claw_orphan_ack_drain);
INIT_DELAYED_WORK(&drvdata->cfg_resume, &cfg_resume_fn);
INIT_DELAYED_WORK(&drvdata->cfg_setup, &cfg_setup_fn);
INIT_DELAYED_WORK(&drvdata->rgb_queue, &claw_rgb_queue_fn);
@@ -1934,6 +1955,7 @@ static void claw_remove(struct hid_device *hdev)
cancel_delayed_work_sync(&drvdata->cfg_resume);
cancel_delayed_work_sync(&drvdata->cfg_setup);
+ cancel_work_sync(&drvdata->orphan_ack_work);
scoped_guard(spinlock_irqsave, &drvdata->registration_lock) {
/* Pairs with smp_store_release from cfg_setup_fn in system_wq context */@@ -2014,6 +2036,7 @@ static int claw_suspend(struct hid_device *hdev)
cancel_delayed_work_sync(&drvdata->cfg_resume);
cancel_delayed_work_sync(&drvdata->cfg_setup);
+ cancel_work_sync(&drvdata->orphan_ack_work);
cancel_delayed_work_sync(&drvdata->rgb_queue);
return 0;
--
2.56.0