Meizu MX4 Ubuntu edition not mounting as USB drive and not available to adb

Question

My Meizu MX4 Ubuntu edition arrived this week and I'm figuring out how to use it. One big problem is that I can't get USB access to copy data, either as a USB drive or using adb. My computer is a MacBook running Yosemite, I also have a Raspberry Pi running Ubuntu Trusty. When I plug the phone into the MacBook there's a bunch of stuff in the phone's dmesg:

[102352.913708] musb-hdrc musb-hdrc: <== Power=f1, DevCtl=99, int_usb=0x4
[102352.913731] musb-hdrc musb-hdrc: BUS RESET as b_peripheral
[102352.913784] [U3D][U2 RESET_INTR]
[102352.913791] [U3D]USB Speed = High Speed
[102353.215731] mtp_open
[102353.253474] mtp_release
[102353.253498] mtp_release, line 1846: _mtp_dev->dev_disconnected = 1
[102353.332582] mtp_open
[102353.356133] mtp_release
[102353.356156] mtp_release, line 1846: _mtp_dev->dev_disconnected = 1
[102353.432300] mtp_open
[102353.450624] mtp_release
[102353.450647] mtp_release, line 1846: _mtp_dev->dev_disconnected = 1
[102353.518418] mtp_open
[102353.540273] mtp_release
[102353.540295] mtp_release, line 1846: _mtp_dev->dev_disconnected = 1
[102353.602370] mtp_open
[102353.623471] mtp_release
[102353.623495] mtp_release, line 1846: _mtp_dev->dev_disconnected = 1
[102353.663670] android_usb gadget: high-speed config #1: android
[102353.663691] mtp_function_set_alt intf: 0 alt: 0
[102353.733945] mtp_open

But there's nothing at all in the MacBook's dmesg. If I insert a normal USB stick the MacBook shows something like:

USBMSC Identifier (non-unique): C86000BDB9EACEB1BA2F8CAD 0x930 0x6544 0x100, 2

If I plug into the Raspberry Pi dmesg shows:

[ 8931.487843] usb 1-1.3: new high-speed USB device number 10 using dwc_otg
[ 8931.577504] usb 1-1.3: New USB device found, idVendor=2a45, idProduct=0c02
[ 8931.577529] usb 1-1.3: New USB device strings: Mfr=2, Product=3, SerialNumber=4
[ 8931.577546] usb 1-1.3: Product: MX4_Ubuntu_Edition 
[ 8931.577561] usb 1-1.3: Manufacturer: meizu
[ 8931.577576] usb 1-1.3: SerialNumber: 750ABLMPX44Y

I can then use lsusb to get more information:

ubuntu@ubuntu:~$ lsusb
Bus 001 Device 006: ID 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode)
Bus 001 Device 005: ID 0bda:8176 Realtek Semiconductor Corp. RTL8188CUS 802.11n WLAN Adapter
Bus 001 Device 010: ID 2a45:0c02  
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. SMSC9512/9514 Fast Ethernet Adapter
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

lsusb doesn't know who "2a45" is even though dmesg apparently does. Following the suggestion of @Maarten Klop I added 0x2a45 to ~/.android/adb and adb now shows:

ubuntu@ubuntu:~$ adb devices
List of devices attached 
????????????    no permissions

I can't put or get files and I can't get a shell because of a lack of permissions.

On the MacBook, if I use Android Device Monitor, I see a listing under Devices for "mx4_ubuntu_edition-750ABLMPX44Y". But again I can't get access to any files, logs, or do anything useful.

Answer 1

Screen must be unlocked, I did not experience USB port issues. For me, this was the critical step:

The file ~/.android/adb_usb.ini on your computer is a list of valid vendorIDs that are allowed to connect. I found that list empty (or non existent, don't remember). Just add a new line with the vendorID for the MX4, you found it already:

0x2a45

I also had to do this for Aquaris E4.5, then the ID is 0x2a47.

Good luck!

Answer 2

The MX4 USB port is picky and unstable with USB3.0. Please try to connect to USB2.0 port or USB2.0 hub to see if it fixed your issue.

Answer 3

I've had a similar problem with my BQ and found out that it shows up as a drive only while the screen is unlocked.

If that doesn't work you might want to enable developer mode (System Settings -> About this phone -> Developer Mode) before trying one more time with the unlocked screen.