Connecting Camera / USB / not an MTP device / udev / CentOS

_alex_ · 08-01-2019, 05:33 AM

Hi,

I'm trying to connect my camera (Canon EOS Kiss X4 = 550D) through USB cable but for some reason it doesn't work with my CentOS 7.

var/log says

Quote:

Aug 1 12:17:20 localhost kernel: usb 3-2: new high-speed USB device number 15 using xhci_hcd
Aug 1 12:17:20 localhost kernel: usb 3-2: New USB device found, idVendor=04a9, idProduct=31ea
Aug 1 12:17:20 localhost kernel: usb 3-2: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Aug 1 12:17:20 localhost kernel: usb 3-2: Product: Canon Digital Camera
Aug 1 12:17:20 localhost kernel: usb 3-2: Manufacturer: Canon Inc.
Aug 1 12:17:20 localhost mtp-probe: checking bus 3, device 15: "/sys/devices/pci0000:00/0000:00:1c.3/0000:19:00.0/usb3/3-2"
Aug 1 12:17:20 localhost mtp-probe: bus: 3, device: 15 was not an MTP device
Aug 1 12:17:52 localhost kernel: usb 3-2: USB disconnect, device number 15

udevadm monitor shows

Quote:

KERNEL[17552.038664] add /devices/pci0000:00/0000:00:1c.3/0000:19:00.0/usb3/3-2 (usb)
KERNEL[17552.039442] add /devices/pci0000:00/0000:00:1c.3/0000:19:00.0/usb3/3-2/3-2:1.0 (usb)
UDEV [17552.086414] add /devices/pci0000:00/0000:00:1c.3/0000:19:00.0/usb3/3-2 (usb)
UDEV [17552.088596] add /devices/pci0000:00/0000:00:1c.3/0000:19:00.0/usb3/3-2/3-2:1.0 (usb)
KERNEL[17583.577266] remove /devices/pci0000:00/0000:00:1c.3/0000:19:00.0/usb3/3-2/3-2:1.0 (usb)
KERNEL[17583.578127] remove /devices/pci0000:00/0000:00:1c.3/0000:19:00.0/usb3/3-2 (usb)
UDEV [17583.580727] remove /devices/pci0000:00/0000:00:1c.3/0000:19:00.0/usb3/3-2/3-2:1.0 (usb)
UDEV [17583.600850] remove /devices/pci0000:00/0000:00:1c.3/0000:19:00.0/usb3/3-2 (usb)

I tried fiddling with udev rules but I get the same results quoted above.
Taking the usb ID from lsusb command

Quote:

Bus 003 Device 016: ID 04a9:31ea Canon, Inc. EOS Rebel T2i / EOS 550D / EOS Kiss X4

and created a rule in

Quote:

/etc/udev/rules.d/90-myrules.rules

with the following line

Quote:

SUBSYSTEMS=="usb", ENV{MTP_NO_PROBE}="1", ENV{MODALIAS}=="usb:04a9:31ea", ENV{MODALIAS}="usb-storage"

The Shotwell app sees for a small instant the camera and then pops the error : "Unable to fetch previews from the camera: Unsupported operations (-6)" which is a result of the usb failure I believe, but just thought of providing this additional info.

Googled the stuff but can't find a solution and am not very knowledgeable on udev, any one has an idea ?

Thanks in advance
Alex

michaelk · 08-01-2019, 08:29 AM

From what little I know, Canon cameras are PTP by default as far as I know and not USB mass storage devices. I don't know if you can switch modes in the camera. While your camera is supported by gPhoto there was an issue where it only worked when connected to a USB 2 and not USB 3 port. You might have to upgrade the kernel.

gphoto2 is probably not installed by default but it should be to detect the camera and display its protocol.

gphoto2 --auto-detect