Re: STM32F723E-Disco: how to use USB in high-speed mode

Dirk-Jan C. Binnema

On Friday May 21 2021, Dirk-Jan C. Binnema via wrote:

Dear List,

I'm trying to use the USB-OTG HS port on an STM32F723E Discovery Board
to mount a ramdisk on a Linux 5.11 host; this works fine in FS-mode;
however, I want to use high-speed mode instead.

In an overlay file I have:
&usbotg_fs {
status = "disabled";

&usbotg_hs {
pinctrl-0 = <&usb_otg_hs_dm_pb14 &usb_otg_hs_dp_pb15>;
maximum-speed = "high-speed";
status = "okay";
(based on the data sheet / some older posts)

This *almost* works, but Linux fails to mount (dmesg output):

To reply to myself: it actually _does_ work when I tried some other
machine running Debian Testing / kernel 4.9 (using ehci_hdc rather than
xhci_hcd); even there it can take up to a minute or so for the mounting
to succeed.

Since this is only for testing, it's good enough for me, but still would
be nice to have the mounting to work smoothly will all kernels.

Also note the

| > usb 1-3: config 1 interface 0 altsetting 0 bulk endpoint 0x81 has
| > invalid maxpacket 64

I think for mass-storage maxpacket the value should be 512 instead
(hence the warning)... is this a bug?

Kind regards,

Dirk-Jan C. Binnema Helsinki, Finland
gpg: 6987 9CED 1745 9375 0F14 DA98 11DD FEA9 DCC4 A036

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