[PATCH v3 0/2] usb: core: fix failed device driver probes, add pre_probe

[James Clark]

On a BeagleY-AI with BeagleBoard's device tree, kernels since commit
f918e3804498 ("arm64: enable HAVE_SHARED_GPIOS for all ARM64 platforms")
no longer boot to a usable system: the on-board USB hub is re-probed in
a loop. Patch 2 fixes this as Johan Hovold suggested, with a pre_probe
callback that lets onboard_usb_dev defer before the hub is configured.

Patch 1 fixes two pre-existing bugs found by a Sashiko review of v2.

Tested on the BeagleY-AI on top of v7.4-rc1: the board boots normally.
The -ENODEV fallback that patch 1 changes is not reached on this board.

I found this by booting commit 85b4bc79dde7 (net/main during the 7.4
merge window) on a BeagleY-AI with BeagleBoard's device tree. A coding
agent identified the problem, explained it to me and proposed an initial
fix, which was revised numerous times on the basis of comments on v1 and
v2, my feedback and local Sashiko reviews. I verified that the series
fixes the problem on top of v7.4-rc1.

v3:
- Add a patch to fix existing problems, as requested by Alan Stern.
- Patch 2: rebased on it, no other change.
v2: https://lore.kernel.org/all/20261030151919.3511106-1-jjc@xxxxxxxxxx/
v1: https://lore.kernel.org/all/20261030114705.3159093-1-jjc@xxxxxxxxxx/

#regzbot introduced: f918e3804498

James Clark (2):
  usb: core: clean up before handing a device to the generic driver
  usb: core: add a pre_probe callback for device drivers that may defer

 drivers/usb/core/driver.c          | 42 ++++++++++++++++++++++++++----
 drivers/usb/misc/onboard_usb_dev.c | 15 ++++++-----
 include/linux/usb.h                | 14 ++++++++++
 3 files changed, 59 insertions(+), 12 deletions(-)


base-commit: 6628e7d4c6b25c8d18f1345e3a20d21829aae7e4
-- 
2.56.0