[PATCH v2 5/9] HID: haptic: Postpone GET_REPORT to init

From
Rong Zhang <i@rong.moe>
Date
2026-11-09 19:50:50
Also in
lkml
Reply to
Rong Zhang, 2026-11-09
Currently, the driver calls GET_REPORT within the feature_mapping
callback. This is not optimal, as the driver works only if manual
trigger is also available and the if the device is a touchpad. It makes
no sense to initiate device IO if the device is not supported by the
driver.

Hence, postpone GET_REPORT to hid_haptic_init(), and parse default
trigger in parse_auto_trigger_field() where many fields are already
parsed there.

Signed-off-by: Rong Zhang <i@rong.moe>
---
 drivers/hid/hid-haptic.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)
diff --git a/drivers/hid/hid-haptic.c b/drivers/hid/hid-haptic.c
index 84985ad61d45..9f2af082d2ea 100644
--- a/drivers/hid/hid-haptic.c
+++ b/drivers/hid/hid-haptic.c
@@ -22,13 +22,6 @@ void hid_haptic_feature_mapping(struct hid_device *hdev,
 				"HID_HP_AUTOTRIGGER out of range\n");
 			return;
 		}
-
-		hid_device_io_start(hdev);
-		hid_hw_request(hdev, field->report, HID_REQ_GET_REPORT);
-		hid_hw_wait(hdev);
-		hid_device_io_stop(hdev);
-		haptic->default_auto_trigger =
-			field->value[usage->usage_index];
 		haptic->auto_trigger_report = field->report;
 	} else if ((usage->hid & HID_USAGE_PAGE) == HID_UP_ORDINAL) {
 		usage_hid = usage->hid & HID_USAGE;
@@ -146,6 +139,9 @@ static void parse_auto_trigger_field(struct hid_haptic_device *haptic,
 			break;
 		case HID_UP_HAPTIC:
 			switch (field->usage[n].hid) {
+			case HID_HP_AUTOTRIGGER:
+				haptic->default_auto_trigger = field->value[n];
+				break;
 			case HID_HP_WAVEFORMVENDORID:
 				haptic->vendor_id = field->value[n];
 				break;
@@ -465,6 +461,12 @@ int hid_haptic_init(struct hid_device *hdev,
 		HID_HP_WAVEFORMSTOP & HID_USAGE;
 
 	mutex_init(&haptic->auto_trigger_mutex);
+
+	hid_device_io_start(hdev);
+	hid_hw_request(hdev, haptic->auto_trigger_report, HID_REQ_GET_REPORT);
+	hid_hw_wait(hdev);
+	hid_device_io_stop(hdev);
+
 	for (r = 0; r < haptic->auto_trigger_report->maxfield; r++)
 		parse_auto_trigger_field(haptic, haptic->auto_trigger_report->field[r]);
 
-- 
2.55.0
Thread (14 messages) 14 messages, 2 authors, last reply 3d ago
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