Gadget not visible from amp / linux box

[jeanparpaillon]

Hi,
First, thanks for this nice piece of code.

I could compile, install, insmod g_ipod modules.
/dev/iap0 is showing up and ipod command can connect to it.

However, on my linux laptop, I can not see the rpi0 with lsusb. I have also tried with a Denon AVR-X1200W amp and the rpi0 is not detected, ipod trace does not show any command.

Is it normal lsusb does not show any device with the product_id ? What may be wrong ?

My config:

$ cat /boot/cmdline.txt 
console=serial0,115200 console=tty1 root=PARTUUID=b36d4013-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait modules-load=dwc2,libcomposite,g_ipod_audio,g_ipod_hid,g_ipod_gadget g_ipod_gadget.swap_configs=1 g_ipod_gadget.product_id=0x1297

$ cat /etc/debian_version 
10.6

$ uname -r
5.4.79+

$ sudo lsmod |grep g_ipod
g_ipod_gadget          16384  0
g_ipod_hid             20480  1
g_ipod_audio           20480  2
snd_pcm                94208  2 snd_bcm2835,g_ipod_audio
snd                    73728  6 snd_timer,snd_bcm2835,g_ipod_audio,snd_pcm
libcomposite           57344  4 g_ipod_gadget,g_ipod_hid,usb_f_mass_storage,g_ipod_audio
udc_core               53248  5 g_ipod_hid,usb_f_mass_storage,dwc2,libcomposite,g_ipod_audio

[oandrew]

Hi,

What's dmesg output on rpi?

rpi should be visible in lsusb (keep in mind usb gadget is active only while /dev/iap0 is open)

Some ideas:

• make sure usb peripheral mode is configured correctly on rpi
• test with other in-tree gadgets e.g. g_serial

https://learn.adafruit.com/turning-your-raspberry-pi-zero-into-a-usb-gadget/overview

[jeanparpaillon]

Thank you for your answer.
I've tried many configurations with other gadget drivers and it looks like there is some hardware issue.

Here is my dmesg output:

$ cat /srv/scratch/mercedes/dmesg 
[    0.000000] Booting Linux on physical CPU 0x0
[    0.000000] Linux version 5.4.79+ (dom@buildbot) (gcc version 8.4.0 (Ubuntu/Linaro 8.4.0-3ubuntu1)) #1373 Mon Nov 23 13:18:15 GMT 2020
[    0.000000] CPU: ARMv6-compatible processor [410fb767] revision 7 (ARMv7), cr=00c5387d
[    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT nonaliasing instruction cache
[    0.000000] OF: fdt: Machine model: Raspberry Pi Zero W Rev 1.1
[    0.000000] Memory policy: Data cache writeback
[    0.000000] Reserved memory: created CMA memory pool at 0x17c00000, size 64 MiB
[    0.000000] OF: reserved mem: initialized node linux,cma, compatible id shared-dma-pool
[    0.000000] On node 0 totalpages: 114688
[    0.000000]   Normal zone: 1008 pages used for memmap
[    0.000000]   Normal zone: 0 pages reserved
[    0.000000]   Normal zone: 114688 pages, LIFO batch:31
[    0.000000] pcpu-alloc: s0 r0 d32768 u32768 alloc=1*32768
[    0.000000] pcpu-alloc: [0] 0 
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 113680
[    0.000000] Kernel command line: coherent_pool=1M 8250.nr_uarts=1 snd_bcm2835.enable_compat_alsa=0 snd_bcm2835.enable_hdmi=1 bcm2708_fb.fbwidth=656 bcm2708_fb.fbheight=416 bcm2708_fb.fbswap=1 smsc95xx.macaddr=B8:27:EB:D3:42:37 vc_mem.mem_base=0x1ec00000 vc_mem.mem_size=0x20000000  console=ttyS0,115200 console=tty1 root=PARTUUID=b36d4013-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait modules-load=dwc2,libcomposite,g_ipod_audio,g_ipod_hid,g_ipod_gadget g_ipod_gadget.swap_configs=1 g_ipod_gadget.product_id=0x1297
[    0.000000] Dentry cache hash table entries: 65536 (order: 6, 262144 bytes, linear)
[    0.000000] Inode-cache hash table entries: 32768 (order: 5, 131072 bytes, linear)
[    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
[    0.000000] Memory: 376184K/458752K available (7814K kernel code, 712K rwdata, 2468K rodata, 512K init, 804K bss, 17032K reserved, 65536K cma-reserved)
[    0.000000] SLUB: HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
[    0.000000] ftrace: allocating 27740 entries in 55 pages
[    0.000000] NR_IRQS: 16, nr_irqs: 16, preallocated irqs: 16
[    0.000000] random: get_random_bytes called from start_kernel+0x2a8/0x4d8 with crng_init=0
[    0.000020] sched_clock: 32 bits at 1000kHz, resolution 1000ns, wraps every 2147483647500ns
[    0.000077] clocksource: timer: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1911260446275 ns
[    0.000178] bcm2835: system timer (irq = 27)
[    0.000758] Console: colour dummy device 80x30
[    0.001331] printk: console [tty1] enabled
[    0.001422] Calibrating delay loop... 697.95 BogoMIPS (lpj=3489792)
[    0.050346] pid_max: default: 32768 minimum: 301
[    0.050646] LSM: Security Framework initializing
[    0.050981] Mount-cache hash table entries: 1024 (order: 0, 4096 bytes, linear)
[    0.051044] Mountpoint-cache hash table entries: 1024 (order: 0, 4096 bytes, linear)
[    0.052986] Disabling memory control group subsystem
[    0.053260] CPU: Testing write buffer coherency: ok
[    0.054775] Setting up static identity map for 0x8200 - 0x8238
[    0.055847] devtmpfs: initialized
[    0.068331] VFP support v0.3: implementor 41 architecture 1 part 20 variant b rev 5
[    0.068796] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns
[    0.068881] futex hash table entries: 256 (order: -1, 3072 bytes, linear)
[    0.076853] pinctrl core: initialized pinctrl subsystem
[    0.078536] NET: Registered protocol family 16
[    0.083292] DMA: preallocated 1024 KiB pool for atomic coherent allocations
[    0.089399] audit: initializing netlink subsys (disabled)
[    0.091697] hw-breakpoint: found 6 breakpoint and 1 watchpoint registers.
[    0.091760] hw-breakpoint: maximum watchpoint size is 4 bytes.
[    0.091940] Serial: AMBA PL011 UART driver
[    0.095394] bcm2835-mbox 2000b880.mailbox: mailbox enabled
[    0.100630] audit: type=2000 audit(0.080:1): state=initialized audit_enabled=0 res=1
[    0.120702] raspberrypi-firmware soc:firmware: Attached to firmware from 2020-11-25 17:12, variant start
[    0.130719] raspberrypi-firmware soc:firmware: Firmware hash is 2e6292a5304b95ecfd700fc5ab2b793402056332
[    0.190858] bcm2835-dma 20007000.dma: DMA legacy API manager, dmachans=0x1
[    0.193877] SCSI subsystem initialized
[    0.194157] usbcore: registered new interface driver usbfs
[    0.194293] usbcore: registered new interface driver hub
[    0.194586] usbcore: registered new device driver usb
[    0.197259] clocksource: Switched to clocksource timer
[    1.666845] VFS: Disk quotas dquot_6.6.0
[    1.667036] VFS: Dquot-cache hash table entries: 1024 (order 0, 4096 bytes)
[    1.667494] FS-Cache: Loaded
[    1.667884] CacheFiles: Loaded
[    1.685882] thermal_sys: Registered thermal governor 'step_wise'
[    1.686540] NET: Registered protocol family 2
[    1.687996] tcp_listen_portaddr_hash hash table entries: 512 (order: 0, 4096 bytes, linear)
[    1.688111] TCP established hash table entries: 4096 (order: 2, 16384 bytes, linear)
[    1.688226] TCP bind hash table entries: 4096 (order: 2, 16384 bytes, linear)
[    1.688350] TCP: Hash tables configured (established 4096 bind 4096)
[    1.688546] UDP hash table entries: 256 (order: 0, 4096 bytes, linear)
[    1.688619] UDP-Lite hash table entries: 256 (order: 0, 4096 bytes, linear)
[    1.689093] NET: Registered protocol family 1
[    1.690304] RPC: Registered named UNIX socket transport module.
[    1.690365] RPC: Registered udp transport module.
[    1.690397] RPC: Registered tcp transport module.
[    1.690428] RPC: Registered tcp NFSv4.1 backchannel transport module.
[    1.692075] hw perfevents: no irqs for PMU, sampling events not supported
[    1.692190] hw perfevents: enabled with armv6_1176 PMU driver, 3 counters available
[    1.696336] Initialise system trusted keyrings
[    1.697000] workingset: timestamp_bits=14 max_order=17 bucket_order=3
[    1.713623] FS-Cache: Netfs 'nfs' registered for caching
[    1.715181] NFS: Registering the id_resolver key type
[    1.715291] Key type id_resolver registered
[    1.715328] Key type id_legacy registered
[    1.715382] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[    1.717643] Key type asymmetric registered
[    1.717708] Asymmetric key parser 'x509' registered
[    1.717818] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 249)
[    1.717869] io scheduler mq-deadline registered
[    1.717903] io scheduler kyber registered
[    1.721181] bcm2708_fb soc:fb: FB found 1 display(s)
[    1.732815] Console: switching to colour frame buffer device 82x26
[    1.740402] bcm2708_fb soc:fb: Registered framebuffer for display 0, size 656x416
[    1.750975] Serial: 8250/16550 driver, 1 ports, IRQ sharing enabled
[    1.757747] bcm2835-rng 20104000.rng: hwrng registered
[    1.761365] vc-mem: phys_addr:0x00000000 mem_base=0x1ec00000 mem_size:0x20000000(512 MiB)
[    1.768470] vc-sm: Videocore shared memory driver
[    1.772285] gpiomem-bcm2835 20200000.gpiomem: Initialised: Registers at 0x20200000
[    1.798817] brd: module loaded
[    1.816117] loop: module loaded
[    1.821265] Loading iSCSI transport class v2.0-870.
[    1.825352] usbcore: registered new interface driver smsc95xx
[    1.828481] dwc_otg: version 3.00a 10-AUG-2012 (platform bus)
[    1.831801] dwc_otg: FIQ enabled
[    1.831815] dwc_otg: NAK holdoff enabled
[    1.831825] dwc_otg: FIQ split-transaction FSM enabled
[    1.831845] Module dwc_common_port init
[    1.832326] usbcore: registered new interface driver usb-storage
[    1.835834] mousedev: PS/2 mouse device common for all mice
[    1.840534] bcm2835-wdt bcm2835-wdt: Broadcom BCM2835 watchdog timer
[    1.846750] sdhci: Secure Digital Host Controller Interface driver
[    1.849959] sdhci: Copyright(c) Pierre Ossman
[    1.853873] mmc-bcm2835 20300000.mmcnr: could not get clk, deferring probe
[    1.858019] sdhost-bcm2835 20202000.mmc: could not get clk, deferring probe
[    1.861484] sdhci-pltfm: SDHCI platform and OF driver helper
[    1.865258] ledtrig-cpu: registered to indicate activity on CPUs
[    1.868908] hidraw: raw HID events driver (C) Jiri Kosina
[    1.872206] usbcore: registered new interface driver usbhid
[    1.875181] usbhid: USB HID core driver
[    1.879452] vchiq: vchiq_init_state: slot_zero = (ptrval)
[    1.884373] [vc_sm_connected_init]: start
[    1.893525] [vc_sm_connected_init]: end - returning 0
[    1.899044] Initializing XFRM netlink socket
[    1.901882] NET: Registered protocol family 17
[    1.904848] Key type dns_resolver registered
[    1.909032] registered taskstats version 1
[    1.911764] Loading compiled-in X.509 certificates
[    1.920394] random: fast init done
[    1.931367] uart-pl011 20201000.serial: cts_event_workaround enabled
[    1.934324] 20201000.serial: ttyAMA0 at MMIO 0x20201000 (irq = 81, base_baud = 0) is a PL011 rev2
[    1.943195] printk: console [ttyS0] disabled
[    1.946043] 20215040.serial: ttyS0 at MMIO 0x0 (irq = 53, base_baud = 50000000) is a 16550
[    2.724199] printk: console [ttyS0] enabled
[    2.732436] bcm2835-power bcm2835-power: Broadcom BCM2835 power domains driver
[    2.744824] mmc-bcm2835 20300000.mmcnr: mmc_debug:0 mmc_debug2:0
[    2.753834] mmc-bcm2835 20300000.mmcnr: DMA channel allocated
[    2.791058] sdhost: log_buf @ (ptrval) (97d10000)
[    2.836703] mmc1: queuing unknown CIS tuple 0x80 (2 bytes)
[    2.846904] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[    2.855257] mmc0: sdhost-bcm2835 loaded - DMA enabled (>1)
[    2.866801] of_cfs_init
[    2.892896] of_cfs_init: OK
[    2.898870] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[    2.908526] Waiting for root device PARTUUID=b36d4013-02...
[    2.919973] mmc1: queuing unknown CIS tuple 0x80 (7 bytes)
[    2.962750] mmc0: host does not support reading read-only switch, assuming write-enable
[    2.980573] mmc0: new high speed SDHC card at address 0007
[    2.990809] mmcblk0: mmc0:0007 SD08G 7.42 GiB
[    3.001610]  mmcblk0: p1 p2
[    3.038701] EXT4-fs (mmcblk0p2): INFO: recovery required on readonly filesystem
[    3.049102] EXT4-fs (mmcblk0p2): write access will be enabled during recovery
[    3.098946] mmc1: new high speed SDIO card at address 0001
[    5.808514] EXT4-fs (mmcblk0p2): recovery complete
[    5.822482] EXT4-fs (mmcblk0p2): mounted filesystem with ordered data mode. Opts: (null)
[    5.836239] VFS: Mounted root (ext4 filesystem) readonly on device 179:2.
[    5.855410] devtmpfs: mounted
[    5.867178] Freeing unused kernel memory: 512K
[    5.874703] This architecture does not have kernel memory protection.
[    5.884264] Run /sbin/init as init process
[    6.650820] systemd[1]: System time before build time, advancing clock.
[    6.839404] NET: Registered protocol family 10
[    6.849255] Segment Routing with IPv6
[    6.912637] systemd[1]: systemd 241 running in system mode. (+PAM +AUDIT +SELINUX +IMA +APPARMOR +SMACK +SYSVINIT +UTMP +LIBCRYPTSETUP +GCRYPT +GNUTLS +ACL +XZ +LZ4 +SECCOMP +BLKID +ELFUTILS +KMOD -IDN2 +IDN -PCRE2 default-hierarchy=hybrid)
[    6.945588] systemd[1]: Detected architecture arm.
[    6.979014] systemd[1]: Set hostname to <raspberrypi>.
[    9.346827] random: systemd: uninitialized urandom read (16 bytes read)
[    9.380408] random: systemd: uninitialized urandom read (16 bytes read)
[    9.392380] systemd[1]: Listening on fsck to fsckd communication Socket.
[    9.407446] random: systemd: uninitialized urandom read (16 bytes read)
[    9.418123] systemd[1]: Started Forward Password Requests to Wall Directory Watch.
[    9.440396] systemd[1]: Created slice User and Session Slice.
[    9.455342] systemd[1]: Listening on Syslog Socket.
[    9.469263] systemd[1]: Listening on udev Kernel Socket.
[    9.482400] systemd[1]: Reached target Swap.
[    9.495430] systemd[1]: Listening on udev Control Socket.
[   10.549658] dwc2 20980000.usb: 20980000.usb supply vusb_d not found, using dummy regulator
[   10.612500] dwc2 20980000.usb: 20980000.usb supply vusb_a not found, using dummy regulator
[   10.917544] dwc2 20980000.usb: EPs: 8, dedicated fifos, 4080 entries in SPRAM
[   10.968255] dwc2 20980000.usb: DWC OTG Controller
[   10.975961] dwc2 20980000.usb: new USB bus registered, assigned bus number 1
[   11.047501] dwc2 20980000.usb: irq 33, io mem 0x20980000
[   11.087849] usb usb1: New USB device found, idVendor=1d6b, idProduct=0002, bcdDevice= 5.04
[   11.102294] usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[   11.112803] usb usb1: Product: DWC OTG Controller
[   11.120786] usb usb1: Manufacturer: Linux 5.4.79+ dwc2_hsotg
[   11.129666] usb usb1: SerialNumber: 20980000.usb
[   11.396777] hub 1-0:1.0: USB hub found
[   11.450008] hub 1-0:1.0: 1 port detected
[   11.763360] g_ipod_audio: loading out-of-tree module taints kernel.

[   11.844111] **********************************************************
[   11.853995] **   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **
[   11.863778] **                                                      **
[   11.873538] ** trace_printk() being used. Allocating extra memory.  **
[   11.883229] **                                                      **
[   11.892933] ** This means that this is a DEBUG kernel and it is     **
[   11.902577] ** unsafe for production use.                           **
[   11.912193] **                                                      **
[   11.921811] ** If you see this message and you are not debugging    **
[   11.931390] ** the kernel, report this immediately to your vendor!  **
[   11.940976] **                                                      **
[   11.950518] **   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **
[   11.960003] **********************************************************
[   11.969783] systemd[1]: Started File System Check on Root Device.
[   12.086651] systemd[1]: Starting Remount Root and Kernel File Systems...
[   12.162293] systemd[1]: Started Journal Service.
[   12.532470] ipod-gadget: init
[   12.538525] ipod-gadget: swapping usb configuration: ipod is #1
[   12.547466] ipod-gadget: override usb idProduct: 1297
[   12.617451] g_ipod gadget:  = ipod_bind() 
[   12.759871] Mass Storage Function, version: 2009/09/11
[   12.797607] LUN: removable file: (no medium)
[   12.804832] g_ipod gadget:  = ipod_config_ptp_bind() 
[   12.827522] ipod-gadget-hid: alloc_chrdev_region dev: 241 0
[   12.836105] ipod-gadget-hid: ipod_hid_alloc()
[   12.895689] g_ipod gadget:  = ipod_config_bind() 
[   12.895714] g_ipod gadget:  = ipod_audio_bind() 
[   12.897099] g_ipod gadget:  = ipod_hid_bind(), deactivs=1 
[   12.897138] g_ipod gadget: g_ipod ready
[   12.903939] dwc2 20980000.usb: bound driver g_ipod
[   13.217469] EXT4-fs (mmcblk0p2): re-mounted. Opts: (null)
[   14.165777] systemd-journald[78]: Received request to flush runtime journal from PID 1
[   16.381650] vc_sm_cma: module is from the staging directory, the quality is unknown, you have been warned.
[   16.384410] bcm2835_vc_sm_cma_probe: Videocore shared memory driver
[   16.384436] [vc_sm_connected_init]: start
[   16.418059] mc: Linux media interface: v0.10
[   16.427095] [vc_sm_connected_init]: installed successfully
[   16.506452] snd_bcm2835: module is from the staging directory, the quality is unknown, you have been warned.
[   16.683561] videodev: Linux video capture interface: v2.00
[   16.824428] bcm2835_mmal_vchiq: module is from the staging directory, the quality is unknown, you have been warned.
[   16.838318] bcm2835_mmal_vchiq: module is from the staging directory, the quality is unknown, you have been warned.
[   16.839910] bcm2835_mmal_vchiq: module is from the staging directory, the quality is unknown, you have been warned.
[   16.898589] bcm2835_v4l2: module is from the staging directory, the quality is unknown, you have been warned.
[   16.910944] bcm2835_isp: module is from the staging directory, the quality is unknown, you have been warned.
[   16.960613] bcm2835_codec: module is from the staging directory, the quality is unknown, you have been warned.
[   16.975871] bcm2835-isp bcm2835-isp: Device node output[0] registered as /dev/video13
[   16.978580] bcm2835-isp bcm2835-isp: Device node capture[0] registered as /dev/video14
[   16.980110] bcm2835-isp bcm2835-isp: Device node capture[1] registered as /dev/video15
[   16.980942] bcm2835-isp bcm2835-isp: Device node stats[2] registered as /dev/video16
[   16.980987] bcm2835-isp bcm2835-isp: Register output node 0 with media controller
[   16.981022] bcm2835-isp bcm2835-isp: Register capture node 1 with media controller
[   16.981047] bcm2835-isp bcm2835-isp: Register capture node 2 with media controller
[   16.981073] bcm2835-isp bcm2835-isp: Register capture node 3 with media controller
[   16.981440] bcm2835-isp bcm2835-isp: Loaded V4L2 bcm2835-isp
[   17.001167] bcm2835-codec bcm2835-codec: Device registered as /dev/video10
[   17.001243] bcm2835-codec bcm2835-codec: Loaded V4L2 decode
[   17.047718] bcm2835-codec bcm2835-codec: Device registered as /dev/video11
[   17.047816] bcm2835-codec bcm2835-codec: Loaded V4L2 encode
[   17.091211] bcm2835-codec bcm2835-codec: Device registered as /dev/video12
[   17.091278] bcm2835-codec bcm2835-codec: Loaded V4L2 isp
[   18.495800] cfg80211: Loading compiled-in X.509 certificates for regulatory database
[   18.994000] cfg80211: Loaded X.509 cert 'sforshee: 00b28ddf47aef9cea7'
[   19.468473] brcmfmac: F1 signature read @0x18000000=0x1541a9a6
[   19.487114] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43430-sdio for chip BCM43430/1
[   19.487619] usbcore: registered new interface driver brcmfmac
[   19.519962] brcmfmac mmc1:0001:1: Direct firmware load for brcm/brcmfmac43430-sdio.raspberrypi,model-zero-w.txt failed with error -2
[   19.769483] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43430-sdio for chip BCM43430/1
[   19.769684] brcmfmac: brcmf_c_process_clm_blob: no clm_blob available (err=-2), device may have limited channels available
[   19.770817] brcmfmac: brcmf_c_preinit_dcmds: Firmware: BCM43430/1 wl0: Oct 22 2019 01:59:28 version 7.45.98.94 (r723000 CY) FWID 01-3b33decd
[   26.125516] random: crng init done
[   26.125544] random: 7 urandom warning(s) missed due to ratelimiting
[   26.872362] uart-pl011 20201000.serial: no DMA platform data
[   27.545986] 8021q: 802.1Q VLAN Support v1.8
[   27.686458] Adding 102396k swap on /var/swap.  Priority:-2 extents:1 across:102396k SSFS
[   28.395696] brcmfmac: brcmf_cfg80211_set_power_mgmt: power save enabled
[   29.852777] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
[   31.282722] Bluetooth: Core ver 2.22
[   31.282908] NET: Registered protocol family 31
[   31.282920] Bluetooth: HCI device and connection manager initialized
[   31.290366] Bluetooth: HCI socket layer initialized
[   31.290394] Bluetooth: L2CAP socket layer initialized
[   31.290457] Bluetooth: SCO socket layer initialized
[   31.308563] Bluetooth: HCI UART driver ver 2.3
[   31.308583] Bluetooth: HCI UART protocol H4 registered
[   31.308698] Bluetooth: HCI UART protocol Three-wire (H5) registered
[   31.308976] Bluetooth: HCI UART protocol Broadcom registered
[   32.089344] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[   32.089361] Bluetooth: BNEP filters: protocol multicast
[   32.089391] Bluetooth: BNEP socket layer initialized

[oandrew]

Check if you have dtoverlay=dwc2 in your /boot/config.txt.

[jeanparpaillon]

@oandrew after testing with different cables and simple g_ether or g_serial gadget drivers, I came to the conclusion there should be some hw issue. I am waiting for new rpi0 and then will update this issue

[danboid]

Hi Jean

Did you ever get ipod gadget to work? I'm not getting the device file after loading the kernel modules

[94002.524086] ipod-gadget: init
[94002.524088] udc-core: couldn't find an available UDC - added [g_ipod] to list of pending drivers

I'm trying to use it with a AVR-X2300W amp.

Is there some USB/kernel config option I should know about that should probably be mentioned in the readme to enable USB OTG or something? I'm running Ubuntu 20.04 amd64 so its not a DTB issue.