booting droid 4 xt894 with current kernel

booting hp t410 with current kernel

booting n8x0 with current kernel

unofficial n800 usb host mode

dynamic tick timer for linux

unofficial omap linux patches

linux for psion 5mx and revo kernel patches

proboot linux bootloader for psion 5mx pro

xpsitouch linux touch panel button handler for psion

linux fast serial port enabler for w83627hf

amd 76x native power management for linux

misc amd64 stuff for linux

powerbook 5300/1400 trex pcmcia driver for linux

pjb-100 personal jukebox usb driver for linux-2.6

xawtv-3.76 patch for remote X11 displays

dog toys



Here are some instructions to get droid 4 xt894 booted with mainline kernel.

There is a debug uart at tty[SO]2 multiplexed with the USB connector. To use
it, you need a custom cable with D+ and D- connected to a 3.3V UART. You need
to leave VBUS disconnected to avoid the connector getting multiplexed back to
USB. It's easiest to make the custom UART by ordering a micro-USB-B breakout
board and connecting the USB serial cable wires to it. I used the sparkfun
break out board here, others should work fine too.

The wire connections are: d- device uart tx usb serial rx ftdi yellow, pl2303 white d+ device uart rx usb serial tx ftdi orange, pl2303 green gnd device ground usb serial gnd vbus do not connect Sebastian Reichel has written some instructions on device table, rooting and install. There used to be pretty good instructions on how to unlock droid 4 and install cyanogenmod here. Basically after installing SafeStrap, you have the kexec tools needed to boot mainline kernel with appended dtb. It will multiplex the debug UART on, so you will have some console output. To boot v4.10-rc1 and later mainline kernels built with omap2plus_defconfig, please download the mainline kernel and mainline kexec tools and read the README file here ddroid4-mainline-kexec-0.3.tar.xz. The sha256sum for the file is here. You probably also want to create an installable SafeStrap ROM image. To do clone the ddroid git repo, and follow the instructions in the README file. You will also need the kexec tools above. Note that droid 4 has few limitations. The eMMC partitions are locked down, and changing them risks bricking the system. So it's best to treat eMMC as a giant bootloader for kexec with just few usable partitions :) At least mmcblk1p23 webtop partition can be reformatted as ext4 and used as a minimal root file system and mmcblk1p22 preinstall can be used as home. Or just use the micro-SD card. Also note that droid 4's modem is locked to be usable only with verizon network in the U.S, in other countries any operator seems to work. With patches heading for v4.12, both the mdm6600 and the w3g modem are visible on the USB bus if ohci-omap3 and ehci-omap modules are loaded. The mdm6600 responds to qmicli commands, and w3g responds to AT commands over ttyACM0. It seems something more is needed for LTE though as w3g does not have the SIM card visible. For the w3g modem, there's some earlier information available here, and some reviews here and here. Droid 4 has a motorola custom PMIC called cpcap. It's connected over SPI and controls things like regulators, USB and audio. Linux v4.11 will have a basic MFD CPCAP driver the related regulator driver merged and v4.12 will have various drivers and basic battery charging merged. Unfortunately there is no documentation available for cpcap, but some of the internal components like charging and ADC seem simlar to the ones documented in an NXP PMIC MC1378. Quite a few of the devices on droid 4 can be supported with just a dts configuration. For the droid 4 related patches currently queued into Linux next for merging into the mainline Linux kernel during the next merge window, you can always check the next branch search page. To search what has been queued for "droid 4", you can click here. The keyboard is using omap4-keypad driver and just needs to be configured. I also managed to get the LCD working with the n950-display branch. The lm3532 LCD backlight works with the TI LMU driver patches. Looks like HDMI is working too but only with console right now and only if you plug it in before loading the modules. I have posted some work-in-progress patches against current Linux next to here. As patches get posted and applied to Linux next, and there are omapdrm changes in Linux next, you need to use the Linux next tag as specified in the tar.gz name. For the kernel .config, I'm just using patched up omap2plus_defconfig. I'm currently working on CPCAP ADC and USB PHY drivers. And with the ADC driver we can also read battery status. And after that we can enable battery charging. The ADC driver is needed to detect USB VBUS and ID pin states. Adding support for CPCAP RTC and watchdog should be possible now if somebody has spare cycles to upstream Linux device drivers :) The CPCAP audio I know nothing about, except it seems to use McBSP like twl4030 for example. The modems should be both on EHCI/OHCI USB bus but I have not played with them, they probably need some GPIO pin toggled to enable them and maybe some PHY driver configuration. If you plan on working on adding more support, please coordinate the work on linux-omap mailing list to avoid duplicate work.

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