usb: gadget: always update HS/SS descriptors and create a copy of them

HS and SS descriptors are staticaly created. They are updated during the
bind process with the endpoint address, string id or interface numbers.

After that, the descriptor chain is linked to struct usb_function which
is used by composite in order to serve the GET_DESCRIPTOR requests,
number of available configs and so on.

There is no need to assign the HS descriptor only if the UDC supports
HS speed because composite won't report those to the host if HS support
has not been reached. The same reasoning is valid for SS.

This patch makes sure each function updates HS/SS descriptors
unconditionally and uses the newly introduced helper function to create a
copy the descriptors for the speed which is supported by the UDC.

While at that, also rename f->descriptors to f->fs_descriptors in order
to make it more explicit what that means.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 33 insertions, 46 deletions

diff --git a/drivers/usb/gadget/f_uvc.c b/drivers/usb/gadget/f_uvc.c
index 10f13c1213c7..28ff2546a5b3 100644
--- a/drivers/usb/gadget/f_uvc.c
+++ b/drivers/usb/gadget/f_uvc.c
@@ -583,9 +583,7 @@ uvc_function_unbind(struct usb_configuration *c, struct usb_function *f)
 	usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
 	kfree(uvc->control_buf);
 
-	kfree(f->descriptors);
-	kfree(f->hs_descriptors);
-	kfree(f->ss_descriptors);
+	usb_free_all_descriptors(f);
 
 	kfree(uvc);
 }
@@ -651,49 +649,40 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 	/* sanity check the streaming endpoint module parameters */
 	if (streaming_maxpacket > 1024)
 		streaming_maxpacket = 1024;
+	/*
+	 * Fill in the HS descriptors from the module parameters for the Video
+	 * Streaming endpoint.
+	 * NOTE: We assume that the user knows what they are doing and won't
+	 * give parameters that their UDC doesn't support.
+	 */
+	uvc_hs_streaming_ep.wMaxPacketSize = streaming_maxpacket;
+	uvc_hs_streaming_ep.wMaxPacketSize |= streaming_mult << 11;
+	uvc_hs_streaming_ep.bInterval = streaming_interval;
+	uvc_hs_streaming_ep.bEndpointAddress =
+		uvc_fs_streaming_ep.bEndpointAddress;
 
-	/* Copy descriptors for FS. */
-	f->descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
-
-	/* support high speed hardware */
-	if (gadget_is_dualspeed(cdev->gadget)) {
-		/*
-		 * Fill in the HS descriptors from the module parameters for the
-		 * Video Streaming endpoint.
-		 * NOTE: We assume that the user knows what they are doing and
-		 * won't give parameters that their UDC doesn't support.
-		 */
-		uvc_hs_streaming_ep.wMaxPacketSize = streaming_maxpacket;
-		uvc_hs_streaming_ep.wMaxPacketSize |= streaming_mult << 11;
-		uvc_hs_streaming_ep.bInterval = streaming_interval;
-		uvc_hs_streaming_ep.bEndpointAddress =
-				uvc_fs_streaming_ep.bEndpointAddress;
-
-		/* Copy descriptors. */
-		f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
-	}
+	/*
+	 * Fill in the SS descriptors from the module parameters for the Video
+	 * Streaming endpoint.
+	 * NOTE: We assume that the user knows what they are doing and won't
+	 * give parameters that their UDC doesn't support.
+	 */
+	uvc_ss_streaming_ep.wMaxPacketSize = streaming_maxpacket;
+	uvc_ss_streaming_ep.bInterval = streaming_interval;
+	uvc_ss_streaming_comp.bmAttributes = streaming_mult;
+	uvc_ss_streaming_comp.bMaxBurst = streaming_maxburst;
+	uvc_ss_streaming_comp.wBytesPerInterval =
+		streaming_maxpacket * (streaming_mult + 1) *
+		(streaming_maxburst + 1);
+	uvc_ss_streaming_ep.bEndpointAddress =
+		uvc_fs_streaming_ep.bEndpointAddress;
 
-	/* support super speed hardware */
-	if (gadget_is_superspeed(c->cdev->gadget)) {
-		/*
-		 * Fill in the SS descriptors from the module parameters for the
-		 * Video Streaming endpoint.
-		 * NOTE: We assume that the user knows what they are doing and
-		 * won't give parameters that their UDC doesn't support.
-		 */
-		uvc_ss_streaming_ep.wMaxPacketSize = streaming_maxpacket;
-		uvc_ss_streaming_ep.bInterval = streaming_interval;
-		uvc_ss_streaming_comp.bmAttributes = streaming_mult;
-		uvc_ss_streaming_comp.bMaxBurst = streaming_maxburst;
-		uvc_ss_streaming_comp.wBytesPerInterval =
-			streaming_maxpacket * (streaming_mult + 1) *
-			(streaming_maxburst + 1);
-		uvc_ss_streaming_ep.bEndpointAddress =
-				uvc_fs_streaming_ep.bEndpointAddress;
-
-		/* Copy descriptors. */
+	/* Copy descriptors */
+	f->fs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
+	if (gadget_is_dualspeed(cdev->gadget))
+		f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
+	if (gadget_is_superspeed(c->cdev->gadget))
 		f->ss_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER);
-	}
 
 	/* Preallocate control endpoint request. */
 	uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
@@ -741,9 +730,7 @@ error:
 		kfree(uvc->control_buf);
 	}
 
-	kfree(f->descriptors);
-	kfree(f->hs_descriptors);
-	kfree(f->ss_descriptors);
+	usb_free_all_descriptors(f);
 	return ret;
 }