gphoto2 times out talking to pixel 6a in ptp mode

[bconoboy]

Describe the bug

I am unable to download photos on a pixel 6a using gphoto2, shotwell, etc. The device is in PTP mode. When put into file transfer mode I'm able to copy files by mounting the device, so the problem seems to be particular to PTP mode. The same system, when used with a Galaxy S21 is able to copy files without incident. I've reproduced this problem on two different Linux systems, so the problem does seem to be specific to the device.

I am reporting this issue against Fedora 38, kernel version 6.2.11-300.fc38.x86_64 with gphoto2-2.5.27-5.fc38.x86_64

Name the camera
If this is camera specific, include the camera name as shown by gphoto2 --auto-detect or USB IDs

libgphoto2 and gphoto2 version

$ gphoto2 --auto-detect
Model Port

Google Inc Nexus/Pixel (PTP) usb:005,011

To Reproduce
Steps to reproduce the behavior:

Just running "gphoto2 -l" is sufficient:

$ gphoto2 -l

*** Error ***
PTP Timeout

*** Error ***
An error occurred in the io-library ('Timeout reading from or writing to the port'): No error description available
*** Error (-10: 'Timeout reading from or writing to the port') ***

I will attach a --debug run file to this issue.

[bconoboy]

gphoto2-l--debug.txt

[rjoberon]

Same problem here – both in PTP and MTP mode.

debug_log_mtp_mode.txt
debug_log_ptp_mode.txt

Update: same problem also with gphoto2 2.5.28:
debug_log_ptp_mode.txt

[bconoboy]

Fails on Pixel 7a as well.

[bconoboy]

Update: I was able to resolve this by making 2 changes:

1. Accessing the USB device was blocked by a daemon provided by gvfs-mtp. This manifests as an immediate access error when running "gphoto2 -l". Diagnosing this was as easy as getting a process list, running 'fuser -km /dev/usb/001/006" (Use lsusb to determine bus and device), then I checked which processes were killed from the process list I'd just saved. I simply removed the gvfs-mtp package.
2. Once the device was available, running gphoto2 -l would freeze for several seconds, then report a timeout. This was fixed this by going into the system's firmware (bios) and changing the system's USB mode from Legacy to Auto mode.

Between these two changes I am now able to consistently use gphoto2 and shotwell to access Android devices.