Re: [PATCH v4 00/64] drivers: usb: dwc3: sync code with Linux v6.16

[Mattijs Korpershoek <mkorpershoek@kernel.org>]

On Tue, Jun 30, 2026 at 11:36, Mattijs Korpershoek <mkorpershoek@kernel.org> wrote:

> Hi Jens,
>
> Thank you for the series.
> This is a lot of work.
>
> On Mon, Jun 29, 2026 at 10:43, Jens Wiklander <jens.wiklander@linaro.org> wrote:
>
>> Hi,
>>
>> This is a follow up on my last two patchsets [1] [2], where the latter only
>> with a small change in addition to posting all the patches.
>>
>> The DWC3 USB driver was forked from the Linux kernel v3.19-rc1 eleven years
>> ago by commit 85d5e7075f33 ("usb: dwc3: add dwc3 folder from linux kernel
>> to u-boot"). Since then, not many kernel changes have been ported back into
>> U-Boot.
>>
>> This series synchronizes the DWC3 core with Linux v6.16. To provide
>> a clear audit trail and maintain bisectability, I have structured the
>> series as follows:
>>
>> 1. Restore to Baseline: The first commit reverts U-Boot-specific changes
>>    to drivers/usb/dwc3 to return the directory to a clean v3.19-rc1 state.
>> 2. Milestone Imports: A sequence of 50+ commits follows, each performing
>>    a "snapshot" import of the drivers/usb/dwc3 directory for every major
>>    kernel version (v3.19 through v6.16).
>> 3. U-Boot Adaptation: The final commits (based on Jerome's original work [3])
>>    re-introduce the necessary glue code, XHCI/UDC updates, and build fixes
>>    required for U-Boot integration.
>>
>> Note that this is compile-tested only. The CI pipeline on source.denx.de
>> was used as an OK/NOK indicator [4].
>>
>> These patches are also available at [5].
>
> I've tried this out on the Khadas VIM3 board using
> khadas-vim3_android_defconfig and usb gadget (with fastboot) seems to
> misbehave.
>
> With the series applied, I see:
> """
> U-Boot 2026.07-rc3-00064-g511db6941796 (Jun 30 2026 - 11:20:08 +0200) khadas-vim3
>
> Model: Khadas VIM3
> SoC:   Amlogic Meson G12B (A311D) Revision 29:b (10:2)
> DRAM:  2 GiB (total 3.8 GiB)
> Core:  408 devices, 37 uclasses, devicetree: separate
> MMC:   mmc@ffe03000: 0, mmc@ffe05000: 1, mmc@ffe07000: 2
> Loading Environment from MMC... MMC Device -1 not found
> *** Warning - No MMC card found, using default environment
>
> In:    usbkbd,serial
> Out:   vidconsole,serial
> Err:   vidconsole,serial
> Net:   eth0: ethernet@ff3f0000
>
> Hit any key to stop autoboot: 0
> => fastboot usb 0
> failed to start <NULL>: -12
> g_dnl_register: failed!, error: -12
> exit not allowed from main input shell.
> """
>
> With v2026.07-rc3, I see:
> """
> U-Boot 2026.07-rc3 (Jun 30 2026 - 11:24:04 +0200) khadas-vim3
>
> Model: Khadas VIM3
> SoC:   Amlogic Meson G12B (A311D) Revision 29:b (10:2)
> DRAM:  2 GiB (total 3.8 GiB)
> Core:  408 devices, 37 uclasses, devicetree: separate
> MMC:   mmc@ffe03000: 0, mmc@ffe05000: 1, mmc@ffe07000: 2
> Loading Environment from MMC... MMC Device -1 not found
> *** Warning - No MMC card found, using default environment
>
> In:    usbkbd,serial
> Out:   vidconsole,serial
> Err:   vidconsole,serial
> Net:   eth0: ethernet@ff3f0000
>
> Hit any key to stop autoboot: 0
> => fastboot usb 0
> crq->brequest:0x0
> """
>
> The failure code path seems to go through:
> g_dnl_register("usb_dnl_fastboot");
>   usb_composite_register(&g_dnl_driver);
>     usb_gadget_register_driver(&composite_driver);
>       usb_gadget_probe_driver(driver);
>         udc_bind_to_driver(udc, driver);
>           driver->bind(udc->gadget);
>
>
> I don't know why it's happening but I wanted to give some feedback early
> on.
> I'll have a closer look.

I spend a bit more time on this.

driver->bind() calls fastboot_bind() which fails to configure the input
endpoint with the following code:

	f_fb->in_ep = usb_ep_autoconfig(gadget, &fs_ep_in);

Looking more closely at usb_ep_autoconfig():
* in v2026.07-rc3 we have an ep_matches() that finds the relevant
  endpoint
* with this series, we now have usb_gadget_ep_match_desc() which does
  not behave the same way.

If i put back the original ep_matches() implementation (from
v2026.07-rc3) and call that instead of usb_gadget_ep_match_desc() in
usb_ep_autoconfig_ss(), I can use fastboot again.

I have not studied how different ep_matches() and
usb_gadget_ep_match_desc() are.

>
> Thanks,
> Mattijs
>
>>
>> Thanks,
>> Jens
>>
>> [1] https://lore.kernel.org/u-boot/20260507092843.358908-1-jens.wiklander@linaro.org/
>> [2] https://lore.kernel.org/u-boot/20260624123025.GA3245275@rayden/
>> [3] https://lore.kernel.org/all/20251121153812.2076440-1-jerome.forissier@linaro.org/
>> [4] https://source.denx.de/u-boot/custodians/u-boot-tpm/-/pipelines/30524
>> [5] https://github.com/jenswikl/u-boot-1/tree/poc/usb_dwc3_sync_v4
>>
>> v3 -> v4:
>> - Restored obj-$(CONFIG_$(PHASE_)USB_DWC3_AM62) for dwc3-am62.o
>>
>> RFC v2 -> v3:
>> - Rebased on v2026.07-rc3
>> - Configured out a few prints in drivers/usb/gadget/udc/udc-core.c
>>   to make it build for am335x_evm_defconfig
>> - Applied provided tags in [1]
>> - Published as a branch
>>
>> RFC v1 -> RFC v2:
>> - Split the v1 ("usb: dwc3: re-import from kernel v6.16-rc7") into ("usb:
>>   dwc3: restore to original v3.19-rc1 kernel import"),  ("usb: dwc3: import
>>   from kernel v3.19)..("usb: dwc3: import from kernel v6.16-rc7")
>>
>> Jens Wiklander (60):
>>   usb: dwc3: restore to original v3.19-rc1 kernel import
>>   usb: dwc3: import from kernel v3.19
>>   usb: dwc3: import from kernel v4.0
>>   usb: dwc3: import from kernel v4.1
>>   usb: dwc3: import from kernel v4.2
>>   usb: dwc3: import from kernel v4.3
>>   usb: dwc3: import from kernel v4.4
>>   usb: dwc3: import from kernel v4.5
>>   usb: dwc3: import from kernel v4.6
>>   usb: dwc3: import from kernel v4.7
>>   usb: dwc3: import from kernel v4.8
>>   usb: dwc3: import from kernel v4.9
>>   usb: dwc3: import from kernel v4.10
>>   usb: dwc3: import from kernel v4.11
>>   usb: dwc3: import from kernel v4.12
>>   usb: dwc3: import from kernel v4.13
>>   usb: dwc3: import from kernel v4.14
>>   usb: dwc3: import from kernel v4.15
>>   usb: dwc3: import from kernel v4.16
>>   usb: dwc3: import from kernel v4.17
>>   usb: dwc3: import from kernel v4.18
>>   usb: dwc3: import from kernel v4.19
>>   usb: dwc3: import from kernel v4.20
>>   usb: dwc3: import from kernel v5.0
>>   usb: dwc3: import from kernel v5.1
>>   usb: dwc3: import from kernel v5.2
>>   usb: dwc3: import from kernel v5.3
>>   usb: dwc3: import from kernel v5.4
>>   usb: dwc3: import from kernel v5.5
>>   usb: dwc3: import from kernel v5.6
>>   usb: dwc3: import from kernel v5.7
>>   usb: dwc3: import from kernel v5.8
>>   usb: dwc3: import from kernel v5.9
>>   usb: dwc3: import from kernel v5.10
>>   usb: dwc3: import from kernel v5.11
>>   usb: dwc3: import from kernel v5.12
>>   usb: dwc3: import from kernel v5.13
>>   usb: dwc3: import from kernel v5.14
>>   usb: dwc3: import from kernel v5.15
>>   usb: dwc3: import from kernel v5.16
>>   usb: dwc3: import from kernel v5.17
>>   usb: dwc3: import from kernel v5.18
>>   usb: dwc3: import from kernel v5.19
>>   usb: dwc3: import from kernel v6.0
>>   usb: dwc3: import from kernel v6.1
>>   usb: dwc3: import from kernel v6.2
>>   usb: dwc3: import from kernel v6.3
>>   usb: dwc3: import from kernel v6.4
>>   usb: dwc3: import from kernel v6.5
>>   usb: dwc3: import from kernel v6.6
>>   usb: dwc3: import from kernel v6.7
>>   usb: dwc3: import from kernel v6.8
>>   usb: dwc3: import from kernel v6.9
>>   usb: dwc3: import from kernel v6.10
>>   usb: dwc3: import from kernel v6.11
>>   usb: dwc3: import from kernel v6.12
>>   usb: dwc3: import from kernel v6.13
>>   usb: dwc3: import from kernel v6.14
>>   usb: dwc3: import from kernel v6.15
>>   usb: dwc3: import from kernel v6.16
>>
>> Jerome Forissier (4):
>>   usb: host: re-import xhci-ext-caps.h from kernel v6.16
>>   usb: gadget: re-import epautoconf.c from kernel v6.16
>>   usb: udc: re-import udc-core.c from kernel v6.16
>>   usb: fix build after resync of DWC3 with kernel v6.16
>>
>>  drivers/usb/cdns3/ep0.c                |    8 +-
>>  drivers/usb/common/common.c            |   23 +
>>  drivers/usb/dwc3/Makefile              |   57 +-
>>  drivers/usb/dwc3/core.c                | 1710 ++++++----
>>  drivers/usb/dwc3/core.h                | 1060 ++++--
>>  drivers/usb/dwc3/debug.h               |  432 +++
>>  drivers/usb/dwc3/dwc3-omap.c           |    2 -
>>  drivers/usb/dwc3/ep0.c                 |  737 ++--
>>  drivers/usb/dwc3/gadget.c              | 4256 ++++++++++++++++--------
>>  drivers/usb/dwc3/gadget.h              |  112 +-
>>  drivers/usb/dwc3/glue.h                |   36 +
>>  drivers/usb/dwc3/io.h                  |   29 +-
>>  drivers/usb/dwc3/linux-compat.h        |   16 -
>>  drivers/usb/dwc3/samsung_usb_phy.c     |   77 -
>>  drivers/usb/dwc3/ti_usb_phy.c          |    2 -
>>  drivers/usb/gadget/at91_udc.c          |   46 -
>>  drivers/usb/gadget/atmel_usba_udc.c    |  102 +-
>>  drivers/usb/gadget/ci_udc.c            |  470 ---
>>  drivers/usb/gadget/composite.c         |    2 +-
>>  drivers/usb/gadget/dwc2_udc_otg.c      |  174 +-
>>  drivers/usb/gadget/epautoconf.c        |  289 +-
>>  drivers/usb/gadget/ether.c             |   21 +-
>>  drivers/usb/gadget/f_acm.c             |   20 +-
>>  drivers/usb/gadget/f_fastboot.c        |   10 +-
>>  drivers/usb/gadget/f_mass_storage.c    |    5 +-
>>  drivers/usb/gadget/f_rockusb.c         |   11 +-
>>  drivers/usb/gadget/f_sdp.c             |   12 +-
>>  drivers/usb/gadget/f_thor.c            |   19 +-
>>  drivers/usb/gadget/udc/Makefile        |    1 +
>>  drivers/usb/gadget/udc/udc-core.c      | 1099 +++++-
>>  drivers/usb/host/xhci-dwc3.c           |    4 +-
>>  drivers/usb/host/xhci-ext-caps.h       |  158 +
>>  drivers/usb/host/xhci-exynos5.c        |    2 +-
>>  drivers/usb/mtu3/mtu3_gadget_ep0.c     |   16 +-
>>  drivers/usb/musb-new/musb_gadget_ep0.c |   24 +-
>>  drivers/usb/musb-new/musb_uboot.c      |   39 -
>>  include/dm/device_compat.h             |   13 +
>>  include/dm/read.h                      |   46 +
>>  include/linux/compat.h                 |   15 +
>>  include/linux/usb/ch9.h                |   25 +-
>>  include/linux/usb/gadget.h             |  520 +--
>>  include/linux/usb/otg.h                |   10 +
>>  include/linux/usb/phy.h                |   56 +
>>  43 files changed, 7591 insertions(+), 4175 deletions(-)
>>  create mode 100644 drivers/usb/dwc3/debug.h
>>  create mode 100644 drivers/usb/dwc3/glue.h
>>  delete mode 100644 drivers/usb/dwc3/linux-compat.h
>>  delete mode 100644 drivers/usb/dwc3/samsung_usb_phy.c
>>  create mode 100644 drivers/usb/host/xhci-ext-caps.h
>>
>>
>> base-commit: 76d62273bc8a5dc126ed79ed0fb65e5a97359577
>> -- 
>> 2.43.0