Re: [PATCH] identify firmware version

--- a/drivers/hid/hid-ntrig.c
+++ b/drivers/hid/hid-ntrig.c

@@ -90,6 +90,26 @@ struct ntrig_data {
 };
 
 
+/*
+ * This function converts the 4 byte raw firmware code into
+ * a string containing 5 comma separated numbers.
+ */
+static int ntrig_version_string(unsigned char *raw, char *buf)
+{
+	__u8 a =  (raw[1] & 0b00001110) >> 1;
+	__u8 b =  (raw[0] & 0b00111100) >> 2;
+	__u8 c = ((raw[0] & 0b00000011) << 3) | ((raw[3] & 0b11100000) >> 5);
+	__u8 d = ((raw[3] & 0b00000111) << 3) | ((raw[2] & 0b11100000) >> 5);
+	__u8 e =   raw[2] & 0b00000111;

@@ -848,10 +871,39 @@ static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	if (report)
 		usbhid_submit_report(hdev, report, USB_DIR_OUT);
 
+	data = kmalloc(8, GFP_KERNEL);
+	if (!data) {
+		ret = -ENOMEM;
+		goto err_free;
+	}
+
+	ret = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0),
+			      USB_REQ_CLEAR_FEATURE,
+			      USB_TYPE_CLASS | USB_RECIP_INTERFACE |
+			      USB_DIR_IN,
+			      0x30c, 1, data, 8,
+			      USB_CTRL_SET_TIMEOUT);
+
+	if (ret == 8) {
+		buf = kmalloc(20, GFP_KERNEL);
+		if (!buf) {
+			ret = -ENOMEM;
+			goto err_free_data;
+		}
+
+		ret = ntrig_version_string(&data[2], buf);
+
+		dev_info(&hdev->dev,
+			 "Firmware version: %s (%02x%02x %02x%02x)\n",
+			 buf, data[2], data[3], data[4], data[5]);
+	}
+
 	ret = sysfs_create_group(&hdev->dev.kobj,
 			&ntrig_attribute_group);
 
 	return 0;

+err_free_data:
+	kfree(data);
 err_free:
 	kfree(nd);
 	return ret;