From 5ab9bcf4953ef4b1c48f330e1340527e683baa62 Mon Sep 17 00:00:00 2001
From: Kai Krakow <kai@kaishome.de>
Date: Mon, 4 Mar 2024 01:13:54 +0100
Subject: [PATCH] xpadneo, core: Handle sync events in xpadneo

To properly sync our multiple sub-devices, we need to synchronize the
input frame in xpadneo instead of the generic HID handler, otherwise
we may see input late or duplicated.

See-also: https://github.com/atar-axis/xpadneo/issues/460
See-also: https://github.com/atar-axis/xpadneo/pull/282
Signed-off-by: Kai Krakow <kai@kaishome.de>
---
 hid-xpadneo/src/hid-xpadneo.c  | 10 +++++++++-
 hid-xpadneo/src/xpadneo.h      |  2 ++
 hid-xpadneo/src/xpadneo/core.c | 20 ++++++++++++++++++++
 3 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/hid-xpadneo/src/hid-xpadneo.c b/hid-xpadneo/src/hid-xpadneo.c
index 39cc2ec2..bede173a 100644
--- a/hid-xpadneo/src/hid-xpadneo.c
+++ b/hid-xpadneo/src/hid-xpadneo.c
@@ -917,6 +917,7 @@ static int xpadneo_event(struct hid_device *hdev, struct hid_field *field,
 			input_report_key(gamepad, BTN_PADDLES(1), value & 2 ? 1 : 0);
 			input_report_key(gamepad, BTN_PADDLES(2), value & 4 ? 1 : 0);
 			input_report_key(gamepad, BTN_PADDLES(3), value & 8 ? 1 : 0);
+			xdata->gamepad_sync = true;
 		}
 		goto stop_processing;
 	} else if (usage->type == EV_ABS) {
@@ -928,6 +929,7 @@ static int xpadneo_event(struct hid_device *hdev, struct hid_field *field,
 			/* Linux Gamepad Specification */
 			if (param_gamepad_compliance) {
 				input_report_abs(gamepad, usage->code, value - 32768);
+				xdata->gamepad_sync = true;
 				goto stop_processing;
 			}
 			break;
@@ -967,6 +969,7 @@ static int xpadneo_event(struct hid_device *hdev, struct hid_field *field,
 		if (!keyboard)
 			goto keyboard_missing;
 		input_report_key(keyboard, BTN_SHARE, value);
+		xdata->keyboard_sync = true;
 		goto stop_processing;
 	} else if (xdata->xbox_button_down && (usage->type == EV_KEY)) {
 		if (!(xdata->quirks & XPADNEO_QUIRK_USE_HW_PROFILES)) {
@@ -996,13 +999,16 @@ static int xpadneo_event(struct hid_device *hdev, struct hid_field *field,
 	}
 
 	/* Let hid-core handle the event */
+	xdata->gamepad_sync = true;
 	return 0;
 
 combine_z_axes:
 	if (++xdata->count_abs_z_rz == 2) {
 		xdata->count_abs_z_rz = 0;
-		if (param_enable_rolling_axis)
+		if (param_enable_rolling_axis) {
 			input_report_abs(gamepad, ABS_MISC, xdata->last_abs_rz - xdata->last_abs_z);
+			xdata->gamepad_sync = true;
+		}
 	}
 	return 0;
 
@@ -1114,6 +1120,7 @@ static int xpadneo_probe(struct hid_device *hdev, const struct hid_device_id *id
 
 	xdata->hdev = hdev;
 	hdev->quirks |= HID_QUIRK_INPUT_PER_APP;
+	hdev->quirks |= HID_QUIRK_NO_INPUT_SYNC;
 	hid_set_drvdata(hdev, xdata);
 
 	if (hdev->version == 0x00000903)
@@ -1281,6 +1288,7 @@ static struct hid_driver xpadneo_driver = {
 	.input_configured = xpadneo_input_configured,
 	.probe = xpadneo_probe,
 	.remove = xpadneo_remove,
+	.report = xpadneo_report,
 	.report_fixup = xpadneo_report_fixup,
 	.raw_event = xpadneo_raw_event,
 	.event = xpadneo_event,
diff --git a/hid-xpadneo/src/xpadneo.h b/hid-xpadneo/src/xpadneo.h
index 2a552ff3..727cbc5e 100644
--- a/hid-xpadneo/src/xpadneo.h
+++ b/hid-xpadneo/src/xpadneo.h
@@ -139,6 +139,7 @@ struct xpadneo_devdata {
 	/* logical device interfaces */
 	struct hid_device *hdev;
 	struct input_dev *consumer, *gamepad, *keyboard;
+	bool consumer_sync, gamepad_sync, keyboard_sync;
 	short int missing_reported;
 
 	/* revert fixups on removal */
@@ -193,5 +194,6 @@ struct xpadneo_devdata {
 extern int xpadneo_init_consumer(struct xpadneo_devdata *);
 extern int xpadneo_init_keyboard(struct xpadneo_devdata *);
 extern int xpadneo_init_synthetic(struct xpadneo_devdata *, char *, struct input_dev **);
+extern void xpadneo_report(struct hid_device *, struct hid_report *);
 
 #endif
diff --git a/hid-xpadneo/src/xpadneo/core.c b/hid-xpadneo/src/xpadneo/core.c
index 580d72b6..a338edc5 100644
--- a/hid-xpadneo/src/xpadneo/core.c
+++ b/hid-xpadneo/src/xpadneo/core.c
@@ -35,3 +35,23 @@ extern int xpadneo_init_synthetic(struct xpadneo_devdata *xdata, char *suffix,
 	*devp = input_dev;
 	return 0;
 }
+
+extern void xpadneo_report(struct hid_device *hdev, struct hid_report *report)
+{
+	struct xpadneo_devdata *xdata = hid_get_drvdata(hdev);
+
+	if (xdata->consumer && xdata->consumer_sync) {
+		xdata->consumer_sync = false;
+		input_sync(xdata->consumer);
+	}
+
+	if (xdata->gamepad && xdata->gamepad_sync) {
+		xdata->gamepad_sync = false;
+		input_sync(xdata->gamepad);
+	}
+
+	if (xdata->keyboard && xdata->keyboard_sync) {
+		xdata->keyboard_sync = false;
+		input_sync(xdata->keyboard);
+	}
+}