core, quirks: Add heuristics to detect GameSir Nova controllers

GameSir Nova uses random MAC OUIs. But looking at samples we probably can detect those controllers by checking the descriptor length and masking the OUI for a specific value. See `docs/heuristics/gamesir-nova.md`. Fixes: #484 Tested-by: https://github.com/BakaJzon Signed-off-by: Kai Krakow <[email protected]>
atar-axis · Nov 28, 2024 · 38cd846 · 38cd846
1 parent 8ce85bf
commit 38cd846
Show file tree

Hide file tree

Showing 4 changed files with 35 additions and 7 deletions.
diff --git a/docs/README.md b/docs/README.md
@@ -205,6 +205,8 @@ options hid_xpadneo quirks=3E:42:6C:xx:xx:xx+6
 
 This controller uses emulated profile switching support (see below).
 
+This manufacturer uses random MAC addresses, so we cannot rely on known OUIs. Heuristics try to detect this controller.
+
 
 ## Profile Switching
 

diff --git a/docs/heuristics/gamesir-nova.md b/docs/heuristics/gamesir-nova.md
@@ -0,0 +1,11 @@
+# GameSir Nova OUIs
+
+Gamesir Nova uses random MAC OUIs. We collect them here to implement a
+working heuristic matcher.
+
+| OUI          | Bit representation                      | descriptor length
+| ------------ | --------------------------------------- | -----------------
+| 3E:42:6C     |   `0011 1110 : 0100 0010 : 0110 1100`   | 283
+| ED:BC:9A     |   `1110 1101 : 1011 1100 : 1001 1010`   | 283
+| 6A:07:14     |   `0110 1010 : 0000 0111 : 0001 0100`   | 283
+| **AND mask** | **`0010 1000 : 0000 0000 : 0000 0000`** | **mask 0x28**
diff --git a/hid-xpadneo/src/hid-xpadneo.c b/hid-xpadneo/src/hid-xpadneo.c
@@ -98,17 +98,11 @@ struct quirk {
 };
 
 static const struct quirk xpadneo_quirks[] = {
-	DEVICE_OUI_QUIRK("3E:42:6C",
-			 XPADNEO_QUIRK_NO_PULSE | XPADNEO_QUIRK_NO_MOTOR_MASK |
-			 XPADNEO_QUIRK_NO_TRIGGER_RUMBLE),
 	DEVICE_OUI_QUIRK("98:B6:EA",
 			 XPADNEO_QUIRK_NO_PULSE | XPADNEO_QUIRK_NO_TRIGGER_RUMBLE |
 			 XPADNEO_QUIRK_REVERSE_MASK),
 	DEVICE_OUI_QUIRK("A0:5A:5D", XPADNEO_QUIRK_NO_HAPTICS),
-	DEVICE_OUI_QUIRK("E4:17:D8", XPADNEO_QUIRK_NO_HAPTICS | XPADNEO_QUIRK_NO_TRIGGER_RUMBLE),
-	DEVICE_OUI_QUIRK("ED:BC:9A",
-			 XPADNEO_QUIRK_NO_PULSE | XPADNEO_QUIRK_NO_MOTOR_MASK |
-			 XPADNEO_QUIRK_NO_TRIGGER_RUMBLE),
+	DEVICE_OUI_QUIRK("E4:17:D8", XPADNEO_QUIRK_SIMPLE_CLONE),
 };
 
 struct usage_map {
@@ -1042,6 +1036,8 @@ static int xpadneo_event(struct hid_device *hdev, struct hid_field *field,
 static int xpadneo_init_hw(struct hid_device *hdev)
 {
 	int i, ret;
+	u8 oui_byte;
+	char oui[3] = { };
 	struct xpadneo_devdata *xdata = hid_get_drvdata(hdev);
 
 	if (!xdata->gamepad) {
@@ -1105,6 +1101,20 @@ static int xpadneo_init_hw(struct hid_device *hdev)
 	}
 	kernel_param_unlock(THIS_MODULE);
 
+	/*
+	 * copy the first two characters from the uniq ID (MAC address) and
+	 * expect it being too big to copy, then `kstrtou8()` converts the
+	 * uniq ID "aa:bb:cc:dd:ee:ff" to u8, so we get the first OUI byte
+	 */
+	if ((xdata->original_rsize == 283)
+	    && (strscpy(oui, xdata->gamepad->uniq, sizeof(oui)) == -E2BIG)
+	    && (kstrtou8(oui, 16, &oui_byte) == 0)
+	    && XPADNEO_OUI_MASK(oui_byte, XPADNEO_OUI_MASK_GAMESIR_NOVA)
+	    && ((xdata->quirks & XPADNEO_QUIRK_SIMPLE_CLONE) == 0)) {
+		hid_info(hdev, "enabling heuristic GameSir Nova quirks\n");
+		xdata->quirks |= XPADNEO_QUIRK_SIMPLE_CLONE;
+	}
+
 	if (xdata->quirks > 0)
 		hid_info(hdev, "controller quirks: 0x%08x\n", xdata->quirks);
 

diff --git a/hid-xpadneo/src/xpadneo.h b/hid-xpadneo/src/xpadneo.h
@@ -68,6 +68,11 @@ do { \
 #define XPADNEO_QUIRK_REVERSE_MASK      128
 
 #define XPADNEO_QUIRK_NO_HAPTICS        (XPADNEO_QUIRK_NO_PULSE|XPADNEO_QUIRK_NO_MOTOR_MASK)
+#define XPADNEO_QUIRK_SIMPLE_CLONE      (XPADNEO_QUIRK_NO_HAPTICS|XPADNEO_QUIRK_NO_TRIGGER_RUMBLE)
+
+/* MAC OUI masks */
+#define XPADNEO_OUI_MASK(oui,mask)    (((oui)&(mask))==(mask))
+#define XPADNEO_OUI_MASK_GAMESIR_NOVA 0x28
 
 /* timing of rumble commands to work around firmware crashes */
 #define XPADNEO_RUMBLE_THROTTLE_DELAY   msecs_to_jiffies(50)