On Thu, 2019-08-22 at 14:58 +1000, Benjamin Herrenschmidt wrote:
>
> Ah lovely ... the 338x fails in EP autoconf with f_tcm, digging...
>
> While digging I found this gem:
>
> /* USB3380: use same address for usb and hardware endpoints */
> snprintf(name, sizeof(name), "ep%d%s", usb_endpoint_num(desc),
> usb_endpoint_dir_in(desc) ? "in" : "out");
> ep = gadget_find_ep_by_name(_gadget, name);
> if (ep && usb_gadget_ep_match_desc(_gadget, ep, desc, ep_comp))
> return ep;
>
> Any idea what's that supposed to achieve ?
>
> When ep_match is called, usb_endpoint_num() hasn't been set yet so
> it's always 0 and always fails... or am I missing something ?
Two problems:
- net2280.c doesn't set a max EP size, so autoconfig fails since
f_tcm specifies one. What about this ?
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -940,12 +940,14 @@ int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
if (usb_endpoint_dir_out(desc) && !ep->caps.dir_out)
return 0;
- if (max > ep->maxpacket_limit)
+ if (ep->maxpacket_limit && max > ep->maxpacket_limit)
return 0;
(ie assume that ep->maxpacket_limit 0 means the UDC supports any
legal size)
- No UDC driver other than dummy sets max_streams, and f_tcm requires 4,
so f_tcm will fail with *any* superspeed UDC driver as far as I can tell.
Was it ever tested with USB 3 ?
I'm not sure what the right fix here yet is as I yet have to learn about
what those USB3 streams are :-) For now I've commented things out.
It's still not working yet as configuring f_tcm seems to be a black art
with no useful documentation or examples anywhere (the device shows up on
the host but doesn't bind to any mass storage driver ... yet).
Cheers,
Ben.
