usb: gadget: uvc: Rename uvc_control_ep

The f_uvc code defines an endpoint named "uvc_control_ep" but it
is configured with a non-zero endpoint address and has its
bmAttributes flagged as USB_ENDPOINT_XFER_INT - this cannot be the
VideoControl interface's control endpoint, as the default endpoint
0 is used for that purpose. This is instead the optional interrupt
endpoint that can be contained by a VideoControl interface. There
is also a Class-specific VC Interrupt Endpoint Descriptor and a
SuperSpeed companion descriptor that are also for the VC interface's
interrupt endpoint but are named as though they are for the control
endpoint.

Rename the variables to make that clear.
Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com>
Link: https://lore.kernel.org/r/20230130105045.120886-2-dan.scally@ideasonboard.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/gadget/function/f_uvc.c

@@ -83,7 +83,7 @@ static struct usb_interface_descriptor uvc_control_intf = {
 	.iInterface		= 0,
 };
 
-static struct usb_endpoint_descriptor uvc_control_ep = {
+static struct usb_endpoint_descriptor uvc_interrupt_ep = {
 	.bLength		= USB_DT_ENDPOINT_SIZE,
 	.bDescriptorType	= USB_DT_ENDPOINT,
 	.bEndpointAddress	= USB_DIR_IN,
@@ -92,8 +92,8 @@ static struct usb_endpoint_descriptor uvc_control_ep = {
 	.bInterval		= 8,
 };
 
-static struct usb_ss_ep_comp_descriptor uvc_ss_control_comp = {
-	.bLength		= sizeof(uvc_ss_control_comp),
+static struct usb_ss_ep_comp_descriptor uvc_ss_interrupt_comp = {
+	.bLength		= sizeof(uvc_ss_interrupt_comp),
 	.bDescriptorType	= USB_DT_SS_ENDPOINT_COMP,
 	/* The following 3 values can be tweaked if necessary. */
 	.bMaxBurst		= 0,
@@ -101,7 +101,7 @@ static struct usb_ss_ep_comp_descriptor uvc_ss_control_comp = {
 	.wBytesPerInterval	= cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
 };
 
-static struct uvc_control_endpoint_descriptor uvc_control_cs_ep = {
+static struct uvc_control_endpoint_descriptor uvc_interrupt_cs_ep = {
 	.bLength		= UVC_DT_CONTROL_ENDPOINT_SIZE,
 	.bDescriptorType	= USB_DT_CS_ENDPOINT,
 	.bDescriptorSubType	= UVC_EP_INTERRUPT,
@@ -300,14 +300,14 @@ uvc_function_set_alt(struct usb_function *f, unsigned interface, unsigned alt)
 		if (alt)
 			return -EINVAL;
 
-		uvcg_info(f, "reset UVC Control\n");
-		usb_ep_disable(uvc->control_ep);
+		uvcg_info(f, "reset UVC interrupt endpoint\n");
+		usb_ep_disable(uvc->interrupt_ep);
 
-		if (!uvc->control_ep->desc)
-			if (config_ep_by_speed(cdev->gadget, f, uvc->control_ep))
+		if (!uvc->interrupt_ep->desc)
+			if (config_ep_by_speed(cdev->gadget, f, uvc->interrupt_ep))
 				return -EINVAL;
 
-		usb_ep_enable(uvc->control_ep);
+		usb_ep_enable(uvc->interrupt_ep);
 
 		if (uvc->state == UVC_STATE_DISCONNECTED) {
 			memset(&v4l2_event, 0, sizeof(v4l2_event));
@@ -385,7 +385,7 @@ uvc_function_disable(struct usb_function *f)
 	uvc->state = UVC_STATE_DISCONNECTED;
 
 	usb_ep_disable(uvc->video.ep);
-	usb_ep_disable(uvc->control_ep);
+	usb_ep_disable(uvc->interrupt_ep);
 }
 
 /* --------------------------------------------------------------------------
@@ -521,9 +521,9 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	 * uvc_iad
 	 * uvc_control_intf
 	 * Class-specific UVC control descriptors
-	 * uvc_control_ep
-	 * uvc_control_cs_ep
-	 * uvc_ss_control_comp (for SS only)
+	 * uvc_interrupt_ep
+	 * uvc_interrupt_cs_ep
+	 * uvc_ss_interrupt_comp (for SS only)
 	 * uvc_streaming_intf_alt0
 	 * Class-specific UVC streaming descriptors
 	 * uvc_{fs|hs}_streaming
@@ -533,11 +533,11 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	control_size = 0;
 	streaming_size = 0;
 	bytes = uvc_iad.bLength + uvc_control_intf.bLength
-	      + uvc_control_ep.bLength + uvc_control_cs_ep.bLength
+	      + uvc_interrupt_ep.bLength + uvc_interrupt_cs_ep.bLength
 	      + uvc_streaming_intf_alt0.bLength;
 
 	if (speed == USB_SPEED_SUPER) {
-		bytes += uvc_ss_control_comp.bLength;
+		bytes += uvc_ss_interrupt_comp.bLength;
 		n_desc = 6;
 	} else {
 		n_desc = 5;
@@ -579,11 +579,11 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	uvc_control_header->bInCollection = 1;
 	uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
 
-	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_ep);
+	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_interrupt_ep);
 	if (speed == USB_SPEED_SUPER)
-		UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_control_comp);
+		UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_interrupt_comp);
 
-	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_cs_ep);
+	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_interrupt_cs_ep);
 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_streaming_intf_alt0);
 
 	uvc_streaming_header = mem;
@@ -666,12 +666,12 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 			    (opts->streaming_maxburst + 1));
 
 	/* Allocate endpoints. */
-	ep = usb_ep_autoconfig(cdev->gadget, &uvc_control_ep);
+	ep = usb_ep_autoconfig(cdev->gadget, &uvc_interrupt_ep);
 	if (!ep) {
 		uvcg_info(f, "Unable to allocate control EP\n");
 		goto error;
 	}
-	uvc->control_ep = ep;
+	uvc->interrupt_ep = ep;
 
 	if (gadget_is_superspeed(c->cdev->gadget))
 		ep = usb_ep_autoconfig_ss(cdev->gadget, &uvc_ss_streaming_ep,

drivers/usb/gadget/function/uvc.h

@@ -146,7 +146,7 @@ struct uvc_device {
 	} desc;
 
 	unsigned int control_intf;
-	struct usb_ep *control_ep;
+	struct usb_ep *interrupt_ep;
 	struct usb_request *control_req;
 	void *control_buf;