I could connect to my Android Alcatel Pixi 4 (5) via MTP on Ubuntu 16.04 (there was a bug where the protocol "died unexpectedly" if a file delete was followed by a file copy, but other than that, it worked).
After upgrading to Ubuntu 18.04 I get "protocol died unexpectedly" in Dolphin whenever I try to browse the device.
#> mtp-detect libmtp version: 1.1.13 Listing raw device(s) Device 0 (VID=1bbb and PID=0167) is a Alcatel/TCT 6010D/TCL S950. Found 1 device(s): Alcatel/TCT: 6010D/TCL S950 (1bbb:0167) @ bus 3, dev 2 Attempting to connect device(s) ignoring libusb_claim_interface() = -6PTP_ERROR_IO: failed to open session, trying again after resetting USB interface LIBMTP libusb: Attempt to reset device ignoring libusb_claim_interface() = -6LIBMTP PANIC: failed to open session on second attempt Unable to open raw device 0 OK.
[ 471.588800] usb 3-4: usbfs: process 9290 (gmtp) did not claim interface 0 before use [ 471.715547] usb 3-4: reset high-speed USB device number 3 using xhci_hcd [ 471.864513] usb 3-4: usbfs: process 9290 (gmtp) did not claim interface 0 before use [ 471.864735] usb 3-4: usbfs: process 2562 (events) did not claim interface 0 before use
I tried building libmtp-1.1.15 from source, problem persists. The device works via MTP access on Windows on the same machine.