Motorola Droid 4

Motorola Droid 4
Manufacturer	Motorola
Codename	Maserati
Dimensions	127x67.3x12.7mm
Release Date	2012-02-10
Specifications
SoC	TI OMAP4430
DRAM	1024MB DDR2
Hardware Features
LCD	960x540 4"
Video	PowerVR SGX540
Storage	16GB flash
Sensors	AK8975 compass, LIS3DH accelerometer, ISL29030 proximity and illuminance, TMP105 temperature sensor
Software Features

Status

Feature	Leste supported	Notes
Kernel version	5.7.0	Mainline + some patches not yet in mainline - see https://github.com/maemo-leste/droid4-linux
Serial	Yes	On MicroUSB port, requires special cable
Charging	Yes
Wireless	Yes
Ethernet	N/A
Micro USB	Yes	OTG and USB network
Keyboard	Yes	Slightly modified keyboard layout, see https://www.spinics.net/lists/linux-omap/msg135137.html (TLDR; Shift key produces CTRL, SYM produces ALT, and Caps lock produces SHIFT)
Screen	Yes
3D Acceleration	Yes	PowerVR SGX540 (closed driver) - https://github.com/maemo-leste/pvr-omap4/
Touchscreen	Yes	Capacitive
Audio	Yes	Switch around in alsamixer to get the right outputs working ('Speaker Right' set to 'HiFi' and 'HiFi' set to above 0 gets you output)
2G/3G data	WIP	Works with ofono, no UI yet - see https://github.com/maemo-leste/connui-cellular/
SMS	WIP	Works with ofono. Needs Leste UI
Phone calls	WIP	Works with ofono (good call quality, too), needs Leste UI
Bluetooth	Yes	Needs firmware - install latest firmware-ti-connectivity - See also https://github.com/maemo-leste/bugtracker/issues/290. Currently disabled due to interference with WiFi
FM Transmitter	No	Apparently exists, and will need serdev kernel modules/drivers
FM Receiver	Not yet
Accelerometer	?	Available in /sys, but not yet as input device, needs kernel and MCE work https://github.com/maemo-leste/bugtracker/issues/294
Compass	?	Available in /sys (after loading ak8975 module. No applications using it yet
Proximity sensor	WIP	Sensor works, not yet exposed as evdev device
Ambient Light Sensor	Yes	https://github.com/maemo-leste/mce/pull/8
Vibration Motor	Yes
HDMI-out	WIP	works
TV-out	N/A
GPS	?	Works but is not integrated yet, see GPS
Infrared	N/A	Missing in hardware

Installation

Hardware requirements:

• Droid4 with fully charged battery
• MicroUSB cable
• MicroSD card

Software requirements:

• Host Linux or Windows system
• Android Tools: fastboot
• Flashing tools:
  • XZ Utils and coreutils for Linux
  • Etcher[1] for Windows

Download from https://maedevu.maemo.org/images/droid4/

1. VRZ_XT894_9.8.2O-72_VZW-18-8_CFC.xml.zip
2. flash-droid-4-fw.sh
3. Latest maemo-leste-1.0-armhf-droid4-*.img.xz

Download from https://github.com/tmlind/droid4-kexecboot.git

1. utags-mmcblk1p13.bin
2. droid4-kexecboot.img

Check what kernel version your Android OS runs. For this go to Settings -> About phone. Slide to the bottom, where you can see "Kernel version". If you have at least 3.0.8, you may skip "Updating Android" step below.

Installation:

1. Create a working directory with above mentioned files in it
2. unzip VRZ_XT894_9.8.2O-72_VZW-18-8_CFC.xml.zip
3. Power off Droid4 and connect it to the host machine with MicroUSB cable
4. Start the device in fastboot mode. For this press power button and bottom volume key simultaneously and release them after a second.

Updating Android. This will reinstall the Android OS on your device, deleting all user data. Do a backup, if you want to save something. When everything is ready, go to the working directory mentioned above and run:

pushd VRZ_XT894_9.8.2O-72_VZW-18-8_CFC.xml
sudo bash ../flash-droid-4-fw.sh
popd

Now, assuming you are in the working directory, install kexecboot:

sudo fastboot flash mbm VRZ_XT894_9.8.2O-72_VZW-18-8_CFC.xml/allow-mbmloader-flashing-mbm.bin
sudo fastboot reboot-bootloader
sudo fastboot flash bpsw droid4-kexecboot.img
sudo fastboot flash utags utags-mmcblk1p13.bin
sudo fastboot reboot

If you did "Updating Android" the device should run the firstboot steps. If you didn't, the device should reboot and show kexecboot menu for a few seconds before it boots to Android.

Now, flash the Maemo Leste image to your sdcard:

On Linux:

xzcat maemo-leste-1.0-armhf-droid4-20190227.img.xz | sudo dd status=progress bs=1M of=/dev/MICROSDCARD-DEVICE
sync

On Windows: Use Etcher

Wait for sync to complete and insert MicroSD card into Droid4. Reboot the device and select Maemo Leste from the kexecboot menu.

You should now see Maemo Leste booting up, and it will show you hildon-desktop after a minute.

Updating

• Poweroff device, grab the SD card
• Backup any important files
• Grab latest image from https://maedevu.maemo.org/images/droid4/
• Write it as before : xzcat maemo-leste-1.0-armhf-droid4-20190227.img.xz | sudo dd status=progress bs=1M of=/dev/MICROSDCARD-DEVICE

Notes

The battery in Droid4 is not easily removable. If you got the device stuck, use this combo: power button + bottom volume key. You should hold them for about 7 seconds. Droid4 will then reboot.

If Maemo is still running, you can also hold just the power button for ~10 seconds, and the device will run poweroff.

Some users reported that Bluetooth kernel module interfere badly with the WiFi driver on their devices. Blacklisting the module may help if you have such problems:

echo "blacklist hci_uart" >> /etc/modprobe.d/blacklist.conf

Also see Motorola_Droid_4/Modem Motorola_Droid_4/PowerVR

Also see: http://elektranox.org/droid4/ and http://muru.com/linux/d4/

Serial Cable

As explained at http://muru.com/linux/d4 , the Droid 4 exposes a serial console on the USB port. You can construct the required cable easily by following the instructions there. If you have old Nokia CA-42 or DKU-5 cables, then you can use them with the Droid 4, using instructions at https://jethomson.wordpress.com/2010/02/21/diy-usb-to-serial-cable-for-3usd/

While using the serial cable, if you lose the connection, the following may help:

18:43 < tmlind> sicelo: hmm the uart debug cable multiplexing still has issues, if the uart disappears during boot it should come back with 
                the console login propt later
18:45 < tmlind> try plugging in a pc usb cable then back to uart cable in case that might help

Stuff to try

Blinkenlights

Adding this in rc.local above the exit 0 gets you some blinkenlights to watschen und relaxen.

echo cpu > /sys/class/leds/lm3532::kbd_backlight/trigger # gets you a cpu activity monitor on the keyboard backlight
echo mmc0 > /sys/class/leds/shift-key-light/trigger      # gets you a 'hdd led' of the SD card on the capslock light

Make Audio Automaticaly set up (Temporary Solution)

Adding this in /etc/rc.local above the exit 0 to make audio work from boot.

amixer cset numid=22 HiFi      #set left speaker to HiFi
amixer cset numid=21 HiFi      #set right speaker to HiFi
amixer cset numid=26 HiFi      #set left headset to HiFi
amixer cset numid=25 HiFi      #set right headset to HiFi
amixer cset numid=1  50%       #set HiFi volumes to 50%

Wifi

The WL1285C Wifi chip in the droid 4 has no onboard nvmem to save its calibration parameters or its MAC address. Instead it gets these parameters from a configuration file provided by the kernel. By default a generic file is provided but for optimal range and a correct persistent MAC address a calibration procedure must be performed.

Install necessary tools:

apt-get install ti-utils-wilink6 droid4-wlanconfig

Run calibration:

sudo maserati-calibrate

Phone Call

Make sure there is a SIM in the phone.

Run this over SSH:

Read modem output: 
# cat /dev/motmdm1 &

Online modem:
# printf "AT+CFUN=1\r" > /dev/motmdm1

Connect to network:

# printf "AT+COPS=1\r" > /dev/motmdm1

Print connected network:

# printf "AT+COPS?\r" > /dev/motmdm1

Not sure, do it anyway:

# printf "AT+SCRN=0\r" > /dev/motmdm1

Dial a number:

# printf "ATD+1234567890\r" > /dev/motmdm1

Hang up:

# printf "ATH\r" > /dev/motmdm1

Answer incoming call:

# printf "ATA\r" > /dev/motmdm1

Audio wise, in alsamixer, make sure echo cancellation is turned on. I had to set Call out to "speakerphone" and set the right speaker to "voice" codec, and set volume for both call and voice to something non-zero.

3G Internet

22:12 < pave1> qmicli -d /dev/cdc-wdm0 --wds-follow-network --wds-start-network=apn=internet.t-mobile.cz
22:12 < pave1> route del default
22:12 < pave1> sudo ifconfig wwan0 up
22:12 < pave1> dhclient wwan0

GPS

modprobe gnss-motmdm and point gpsd to use /dev/gnss0

22:30 < tmlind> hmm there's a probably kernel gnss bug for gsp access fyi, you can currently only open one connection before you have to restart gpsd :)

Can try to

mkfifo /tmp/gps
cat /dev/gnss0 > /tmp/gps
Then point gpsd to use /tmp/gps

USSD

22:45 < tmlind> fyi, here's how to send USSD to query balance for example: printf "AT+CUSD=1,#999#,0\r" > /dev/motmdm1
22:47 < tmlind> fyi, for parsing incoming USSD, this web interface works if set to utf-8: 
                https://www.mobilefish.com/services/latin_utf_base64_to_hex/latin_utf_base64_to_hex.php#text_hex_output

Gallery

• 
• 
• 
•