STM32MP15 ECO 5.0 USB gadget: couldn't find an available UDC

[debugging]

Custom SMT32MP15 board connected via the micro USB to a host PC. This board has HDMI via an RGB to HDMI chip but here PA10 is only used for USB OTG-ID)  (there was another post on this about HDMI). Build kernel from ECO 5.0.  The Gadget functions worked fine with ECO 1.

On the host PC lsusb shows : ID 1d6b:0104 Linux Foundation Multifunction Composite Gadget

This would seems the gadget driver is working the  board is in device mode. (right ?)

ls /sys/kernel/debug/usb/49000000.usb-otg/
dr_mode ep1in ep2in ep3in ep4in ep5in ep6in ep7in ep8in fifo params state
ep0 ep1out ep2out ep3out ep4out ep5out ep6out ep7out ep8out hw_params regdump testmode

Board  dts  entries:  (based on the board entries form ECO 1.0 and ST Wiki)

Note: only added this in the kerne; dts, not in uboot.

&usbotg_hs

{

phys = <&usbphyc_port1 0>;

phy-names = "usb2-phy";

pinctrl-names = "default";

pinctrl-0 = <&usbotg_hs_pins_a>;

dr_mode = "otg";

phy-names = "usb2-phy";

// Note enabling usb-role-switch cause Linux Foundation Multifunction Composite Gadget NOT appear on the host

//usb-role-switch;

vbus-supply = <&vbus_otg>;

// added because kernel boot showed these were not found. vbus-otg seemed not enough

vusb_d = <&vdd_usb>;

vusb_a = <&vdd_usb>;

//vbus-supply = <&vdd_usb>;

g-rx-fifo-size = <256>;

g-np-tx-fifo-size = <32>;

g-tx-fifo-size = <128 128 128 128 64 32 16 16>;

status = "okay";

};

in pinctrl section user code  (the board with ECO 1 used this entry for PA10)

usbotg_hs_pins_a: usbotg_hs-0 {
pins {
pinmux = <STM32_PINMUX('A', 10, ANALOG)>; /* OTG_ID */
};
};

ls /sys/class/udc/49000000.usb-otg
a_alt_hnp_support b_hnp_enable device is_a_peripheral is_selfpowered power srp subsystem
a_hnp_support current_speed function is_otg maximum_speed soft_connect state uevent

After creating all the gadget file systems entries

root@stm32mp1:/sys/kernel/config/usb_gadget/g2# echo 0x1235 > idVendor
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# echo 0x800c > idProduct
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# mkdir strings/0x409
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# echo 1234567890 > strings/0x409/serialnumber
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# echo Manufacturer_1 > strings/0x409/manufacturer
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# echo Product > strings/0x409/product
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# mkdir configs/c.1
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# mkdir configs/c.1/strings/0x409
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# echo "Conf 1" > configs/c.1/strings/0x409/configuration
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# echo 120 > configs/c.1/MaxPower
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# ls configs/c.1
MaxPower bmAttributes strings
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# ln -s functions/midi.usb0 configs/c.1
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# ln -s functions/midi.usb1 configs/c.1
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# name="$(ls /sys/class/udc)"
root@stm32mp1:/sys/kernel/config/usb_gadget/g2# echo $name > UDC
[ 288.583969] UDC core: g2: couldn't find an available UDC or it's busy
sh: write error: Device or resource busy

root@stm32mp1:/sys/kernel/config/usb_gadget/g2# ls /sys/class/udc
49000000.usb-otg

in dmesg this was found:

[ 16.422555] dwc2 49000000.usb-otg: bound driver configfs-gadget.g1

moving the the gadget folder

cat UDC
49000000.usb-otg
root@stm32mp1:/sys/kernel/config/usb_gadget/g1# echo "" >UDC
root@stm32mp1:/sys/kernel/config/usb_gadget/g1# echo "49000000.usb-otg" > UDC
[ 1691.036019] stm32mp157-pinctrl soc:pinctrl@50002000: pin PA10 already requested by 49000000.usb-otg; cannot claim for gadget.0
[ 1691.046283] stm32mp157-pinctrl soc:pinctrl@50002000: pin-10 (gadget.0) status -22
[ 1691.053497] stm32mp157-pinctrl soc:pinctrl@50002000: could not request pin 10 (PA10) from group PA10 on device soc:pinctrl@50002000
[ 1691.065508] configfs-gadget.g1 gadget.0: Error applying setting, reverse things back
[ 1691.073372] UDC core: g1: couldn't find an available UDC or it's busy
sh: write error: Device or resource busy
root@stm32mp1:/sys/kernel/config/usb_gadget/g1

Any ideas what/how to debug the root cause ?

Here is some of the dwc2 debug information  (enabled in kernel)

[ 424.658497] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: DxEPCTL=0x00498200, ep 1, dir in
[ 424.666702] dwc2 49000000.usb-otg: ureq->length:300 ureq->actual:0
[ 424.672886] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: 1@300/300, 0x2008012c => 0x00000930
[ 424.681299] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: d9003000 pad => 0x00000934
[ 424.688898] dwc2 49000000.usb-otg: ep0 state:0
[ 424.693362] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: DxEPCTL=0x84498200
[ 424.700351] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: DXEPCTL=0x80498200
[ 424.707365] dwc2 49000000.usb-otg: dwc2_hsotg_irq: 04048028 00040000 (d88c3c44) retry 8
[ 424.715288] dwc2 49000000.usb-otg: dwc2_hsotg_irq: daint=00000002
[ 424.721383] dwc2 49000000.usb-otg: dwc2_hsotg_epint: ep1(in) DxEPINT=0x00000001
[ 424.728584] dwc2 49000000.usb-otg: dwc2_hsotg_epint: XferCompl: DxEPCTL=0x00488200, DXEPTSIZ=1da7bb20
[ 424.737807] dwc2 49000000.usb-otg: dwc2_hsotg_complete_in: adjusting size done 0 => 300
[ 424.745817] dwc2 49000000.usb-otg: req->length:300 req->actual:300 req->zero:1
[ 424.753014] dwc2 49000000.usb-otg: complete: ep be8aa6fc ep1in, req 0cb15717, 0 => 932f0458
[ 437.445522] dwc2 49000000.usb-otg: dwc2_hsotg_irq: 04088028 00080000 (d88c3c44) retry 8
[ 437.452161] dwc2 49000000.usb-otg: dwc2_hsotg_irq: daint=00020000
[ 437.458244] dwc2 49000000.usb-otg: dwc2_hsotg_epint: ep1(out) DxEPINT=0x00000001
[ 437.465641] dwc2 49000000.usb-otg: dwc2_hsotg_epint: XferCompl: DxEPCTL=0x00098200, DXEPTSIZ=1bdf4d2e
[ 437.474859] dwc2 49000000.usb-otg: complete: ep 01bd230a ep1out, req ca238c7d, 0 => 65711172
[ 437.483283] dwc2 49000000.usb-otg: dwc2_hsotg_handle_unaligned_buf_complete: ep1out: status=0 actual-length=362
[ 437.493365] dwc2 49000000.usb-otg: ep1out: req ca238c7d: 16384@48778cb0, noi=0, zero=0, snok=0
[ 437.501887] dwc2 49000000.usb-otg: dwc2_hsotg_handle_unaligned_buf_start: ep1out: buf=48778cb0 length=16384
[ 437.511725] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: DxEPCTL=0x00098200, ep 1, dir out
[ 437.519931] dwc2 49000000.usb-otg: ureq->length:16384 ureq->actual:0
[ 437.526215] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: 32@16384/16384, 0x01004000 => 0x00000b30
[ 437.535132] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: d9004000 pad => 0x00000b34
[ 437.542729] dwc2 49000000.usb-otg: ep0 state:0
[ 437.547192] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: DxEPCTL=0x84098200
[ 437.554179] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: DXEPCTL=0x80098200
[ 439.513086] dwc2 49000000.usb-otg: ep1in: req 0cb15717: 300@86d2c43a, noi=0, zero=1, snok=0
[ 439.520049] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: DxEPCTL=0x00488200, ep 1, dir in
[ 439.528253] dwc2 49000000.usb-otg: ureq->length:300 ureq->actual:0
[ 439.534435] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: 1@300/300, 0x2008012c => 0x00000930
[ 439.542849] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: d9003000 pad => 0x00000934
[ 439.550448] dwc2 49000000.usb-otg: ep0 state:0
[ 439.554912] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: DxEPCTL=0x84488200
[ 439.561902] dwc2 49000000.usb-otg: dwc2_hsotg_start_req: DXEPCTL=0x80488200
[ 439.568878] dwc2 49000000.usb-otg: dwc2_hsotg_irq: 04048028 00040000 (d88c3c44) retry 8
[ 439.576799] dwc2 49000000.usb-otg: dwc2_hsotg_irq: daint=00000002
[ 439.582893] dwc2 49000000.usb-otg: dwc2_hsotg_epint: ep1(in) DxEPINT=0x00000001
[ 439.590195] dwc2 49000000.usb-otg: dwc2_hsotg_epint: XferCompl: DxEPCTL=0x00498200, DXEPTSIZ=1d9fb9f4
[ 439.599419] dwc2 49000000.usb-otg: dwc2_hsotg_complete_in: adjusting size done 0 => 300
[ 439.607430] dwc2 49000000.usb-otg: req->length:300 req->actual:300 req->zero:1