Re: [PATCH] usb: gadget: f_midi: Fixing wMaxPacketSize exceeded issue during MIDI bind retries

Alan Stern
2024-12-18T15:51:55Z

On Wed, Dec 18, 2024 at 03:51:50PM +0530, Selvarasu Ganesan wrote:
> The issue arises during the second time the "f_midi_bind" function is
> called. The problem lies in the fact that the size of
> "bulk_in_desc.wMaxPacketSize" is set to 1024 during the first call,
> which exceeds the hardware capability of the dwc3 TX/RX FIFO
> (ep->maxpacket_limit = 512).

Is this gadget supposed to be able to run at SuperSpeed? I thought the
dwc3 controller supported SuperSpeed operation.

The USB-3 spec requires that all SuperSpeed bulk endpoints must have a
wMaxPacketSize of 1024 (see Table 9-24 on p.9-25 of the USB-3.1
specification).

Alan Stern