[PATCH RESEND 1/4] HID: winwing: factor out vendor SET_LEDX report builder

["René Onier" <f3nr1l@me.com>]

The LED and the rumble paths each open-code the same 14-byte vendor
report byte by byte, leaving the meaning of every field to the reader.
Name the fields and build the report in one place.

A report is addressed to one of the controllers making up the product by
a (device, family) pair: the Orion 2 lighting controller answers on
0x60/0xbe, the two grip rumble motors on 0x01/0xbf and 0x03/0xbf.

No functional change: the bytes put on the wire are identical.

Signed-off-by: René Onier <f3nr1l@me.com>
---
 drivers/hid/hid-winwing.c | 123 +++++++++++++++++++-------------------
 1 file changed, 60 insertions(+), 63 deletions(-)

diff --git a/drivers/hid/hid-winwing.c b/drivers/hid/hid-winwing.c
index cbfdb9c66e..a9bf81c19f 100644
--- a/drivers/hid/hid-winwing.c
+++ b/drivers/hid/hid-winwing.c
@@ -16,6 +16,30 @@
 
 #define MAX_REPORT 16
 
+/*
+ * Vendor output report (report ID 2, 14 bytes):
+ *
+ *	[0] report ID	[1] device	[2] family	[3..4] zero
+ *	[5] payload length	[6] opcode	[7..] arguments
+ *
+ * The device and family bytes select which of the controllers making up the
+ * product the report is addressed to; unknown reports are silently dropped.
+ */
+#define WINWING_REPORT_ID	0x02
+#define WINWING_REPORT_LEN	14
+
+#define WINWING_OP_SET_LEDX	0x49	/* arguments: LED index, value */
+#define WINWING_SET_LEDX_LEN	3
+
+/* Lighting controller of the Orion 2 throttle base */
+#define ORION2_LIGHT_DEVICE	0x60
+#define ORION2_LIGHT_FAMILY	0xbe
+
+/* Rumble motors of the TGRIP-15 grips, one report each */
+#define WINWING_STICK_FAMILY		0xbf
+#define WINWING_RUMBLE_LEFT_DEVICE	0x01
+#define WINWING_RUMBLE_RIGHT_DEVICE	0x03
+
 struct winwing_led {
 	struct led_classdev cdev;
 	struct hid_device *hdev;
@@ -47,36 +71,41 @@ struct winwing_drv_data {
 	struct winwing_led leds[];
 };
 
+/*
+ * Build a vendor report addressed to one controller and send it. The caller
+ * owns @buf and any serialization it needs.
+ *
+ * Mimicking requests captured by usbmon when the LEDs and the rumble motors
+ * are controlled by the vendor's app in a VM.
+ */
+static int winwing_send_set_ledx(struct hid_device *hdev, __u8 *buf,
+		__u8 device, __u8 family, __u8 index, __u8 value)
+{
+	memset(buf, 0, WINWING_REPORT_LEN);
+
+	buf[0] = WINWING_REPORT_ID;
+	buf[1] = device;
+	buf[2] = family;
+	buf[5] = WINWING_SET_LEDX_LEN;
+	buf[6] = WINWING_OP_SET_LEDX;
+	buf[7] = index;
+	buf[8] = value;
+
+	return hid_hw_output_report(hdev, buf, WINWING_REPORT_LEN);
+}
+
 static int winwing_led_write(struct led_classdev *cdev,
 		enum led_brightness br)
 {
 	struct winwing_led *led = (struct winwing_led *) cdev;
 	struct winwing_drv_data *data = hid_get_drvdata(led->hdev);
-	__u8 *buf = data->report_lights;
 	int ret;
 
 	mutex_lock(&data->lights_lock);
 
-	/*
-	 * Mimicking requests captured by usbmon when LEDs
-	 * are controlled by the vendor's app in a VM.
-	 */
-	buf[0] = 0x02;
-	buf[1] = 0x60;
-	buf[2] = 0xbe;
-	buf[3] = 0x00;
-	buf[4] = 0x00;
-	buf[5] = 0x03;
-	buf[6] = 0x49;
-	buf[7] = led->number;
-	buf[8] = br;
-	buf[9] = 0x00;
-	buf[10] = 0;
-	buf[11] = 0;
-	buf[12] = 0;
-	buf[13] = 0;
-
-	ret = hid_hw_output_report(led->hdev, buf, 14);
+	ret = winwing_send_set_ledx(led->hdev, data->report_lights,
+			ORION2_LIGHT_DEVICE, ORION2_LIGHT_FAMILY,
+			led->number, br);
 
 	mutex_unlock(&data->lights_lock);
 
@@ -242,28 +271,12 @@ static int winwing_haptic_rumble(struct winwing_drv_data *data)
 	if (m != data->rumble_left) {
 		int ret;
 
-		/*
-		 * Mimicking requests captured by usbmon when rumble
-		 * is activated by the vendor's app in a VM.
-		 */
-		buf[0] = 0x02;
-		buf[1] = 0x01;
-		buf[2] = 0xbf;
-		buf[3] = 0x00;
-		buf[4] = 0x00;
-		buf[5] = 0x03;
-		buf[6] = 0x49;
-		buf[7] = 0x00;
-		buf[8] = m;
-		buf[9] = 0x00;
-		buf[10] = 0;
-		buf[11] = 0;
-		buf[12] = 0;
-		buf[13] = 0;
-
-		ret = hid_hw_output_report(data->hdev, buf, 14);
+		ret = winwing_send_set_ledx(data->hdev, buf,
+				WINWING_RUMBLE_LEFT_DEVICE,
+				WINWING_STICK_FAMILY, 0, m);
 		if (ret < 0) {
-			hid_err(data->hdev, "error %d (%*ph)\n", ret, 14, buf);
+			hid_err(data->hdev, "error %d (%*ph)\n", ret,
+					WINWING_REPORT_LEN, buf);
 			return ret;
 		}
 		data->rumble_left = m;
@@ -273,28 +286,12 @@ static int winwing_haptic_rumble(struct winwing_drv_data *data)
 	if (m != data->rumble_right) {
 		int ret;
 
-		/*
-		 * Mimicking requests captured by usbmon when rumble
-		 * is activated by the vendor's app in a VM.
-		 */
-		buf[0] = 0x02;
-		buf[1] = 0x03;
-		buf[2] = 0xbf;
-		buf[3] = 0x00;
-		buf[4] = 0x00;
-		buf[5] = 0x03;
-		buf[6] = 0x49;
-		buf[7] = 0x00;
-		buf[8] = m;
-		buf[9] = 0x00;
-		buf[10] = 0;
-		buf[11] = 0;
-		buf[12] = 0;
-		buf[13] = 0;
-
-		ret = hid_hw_output_report(data->hdev, buf, 14);
+		ret = winwing_send_set_ledx(data->hdev, buf,
+				WINWING_RUMBLE_RIGHT_DEVICE,
+				WINWING_STICK_FAMILY, 0, m);
 		if (ret < 0) {
-			hid_err(data->hdev, "error %d (%*ph)\n", ret, 14, buf);
+			hid_err(data->hdev, "error %d (%*ph)\n", ret,
+					WINWING_REPORT_LEN, buf);
 			return ret;
 		}
 		data->rumble_right = m;
-- 
2.55.0