On 10/12/2024 11:45, Ming Yu wrote:

+	nct6694->int_buffer = devm_kcalloc(dev, NCT6694_MAX_PACKET_SZ,
+					   sizeof(unsigned char), GFP_KERNEL);
+	if (!nct6694->int_buffer)
+		return -ENOMEM;
+
+	nct6694->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!nct6694->int_in_urb)
+		return -ENOMEM;
+
+	nct6694->domain = irq_domain_add_simple(NULL, NCT6694_NR_IRQS, 0,
+						&nct6694_irq_domain_ops,
+						nct6694);
+	if (!nct6694->domain)
+		return -ENODEV;
+
+	nct6694->udev = udev;
+	nct6694->timeout = NCT6694_URB_TIMEOUT;	/* Wait until urb complete */
+	nct6694->cmd_header = cmd_header;
+	nct6694->response_header = response_header;
+
+	mutex_init(&nct6694->access_lock);
+	mutex_init(&nct6694->irq_lock);
+
+	usb_fill_int_urb(nct6694->int_in_urb, udev, pipe,
+			 nct6694->int_buffer, maxp, usb_int_callback,
+			 nct6694, int_endpoint->bInterval);
+	ret = usb_submit_urb(nct6694->int_in_urb, GFP_KERNEL);
+	if (ret)
+		goto err_urb;
+
+	dev_set_drvdata(dev, nct6694);
+	usb_set_intfdata(iface, nct6694);
+
+	ret = mfd_add_hotplug_devices(dev, nct6694_dev, ARRAY_SIZE(nct6694_dev));
+	if (ret)
+		goto err_mfd;
+
+	dev_info(dev, "Probed device: (%04X:%04X)\n", id->idVendor, id->idProduct);

Drop. Duplicating existing messages and interfaces. Your driver is
supposed to be silent on success.

+	return 0;
+
+err_mfd:
+	usb_kill_urb(nct6694->int_in_urb);
+err_urb:
+	usb_free_urb(nct6694->int_in_urb);
+	return dev_err_probe(dev, ret, "Probe failed\n");

No, this should go to individual call causing errors so this will be
informative. Above is not informative at all and kernel already reports
this, so drop.

+}
+
+static void nct6694_usb_disconnect(struct usb_interface *iface)
+{
+	struct usb_device *udev = interface_to_usbdev(iface);
+	struct nct6694 *nct6694 = usb_get_intfdata(iface);

Best regards,
Krzysztof