wefullpac

1. Linux Kernel Versions
2. Linux Kernel Mailing List Archive

Synopsis This How-To describes a way to built and install Ubuntu 14.04 from scratch on the ARMv7 based (Freescale imx.6) utilite computer. Before you start Get a serial connection to the utilite computer The utilite has two serial connectors, one at the front ( /dev/ttymxc3) and one at the rear side ( /dev/ttymxc1).

The one at the front ( /dev/ttymxc3) is the default console for the firmware (U-Boot), kernel messages und the Linux environment. I strongly recommend having a serial connection in place; otherwise you cannot interact with the firmware or see what happed when something went wrong. You need a null modem cable (and a serial to USB converter if you computers doesn't have a serial connector). I’m using minicom (Linux) and putty (Windows) as terminal emulators when I connect to a serial console. You may read these links als well. Have an ARMv7 build environment This How-To assumes, that you are not cross compiling. Mac game.

So you need a viable Linux environment on the ARMv7 platform for building Ubuntu 14.04 and compiling the linux kernel. This environment doesn’t need to be an utilite, you may take any other ARMv7 based device as well. I used the official Ubuntu release (12.04) from utilite on the utilite pro.

You will need the debootstrap package installed and a working compiler toolchain as well. Update the U-Boot firmware to the latest release (optional) The latest U-Boot firmware offers some advantages, like booting from USB. If you don’t have an internal SSD, you will love the opportunity to boot from a different device then uSD.

When you update the firmware, you should consider to update the U-Boot environment as well. You should get familiar with the basic U-Boot commands, in order to boot a different kernel or from a non-default device (boot from SSD, even when uSD is present at boot time). Have a boot media You need of cause a boot media on which you put the Ubuntu 14.04. If you update the U-Boot firmware and environment, this could be any USB storage device, otherwise you need a uSD Card (minimum capacity 4GB, I recommend class 10 or better).

Building the Ubuntu 14.04 environment (userland) Step 1: Download and unpack the userland Having the environment in place, you can build the Ubuntu userland issuing the following commands (as root). Mkdir./rootfs debootstrap -foreign -include=vim,dialog,apt -variant=minbase -arch=armhf trusty rootfs This will take some time, debootstrap will download an install the packages required for the minimal Ubuntu installation inside the target directory (./rootfs). If you prefer another text editor like nano, you may append this package to the –include= command line parameter.

What,.another. half-finished blog post about Linux USB drivers?

Suppose you have a device and want a Linux device driver for it. There are a few steps you’ll need to take. One of the heroes in this area is. Greg wrote, which is a Linux tool to enumerate a list of USB devices.

Linux Kernel Versions

He’s also done a massive amount of documentation as we’ll see below. One of his more eye-catching tricks is to walk a classroom through the process of. In addition to all the work he does for Linux in general, he recently announced a program to work with manufacturers.

That’s right, manufacturers get a free driver. From the: All that is needed is some kind of specification that describes how your device works, or the email address of an engineer that is willing to answer questions every once in a while. A few sample devices might be good to have so that debugging doesn’t have to be done by email, but if necessary, that can be done. In return, you will receive a complete and working Linux driver that is added to the main Linux kernel source tree.

The driver will be written by some of the members of the Linux kernel developer community (over 1500 strong and growing). That is majorly good karma for Linux and Greg. But if you’re not a manufacturer, here are the steps that you’d look into. Get documentation of the USB protocol, or reverse engineer the protocol.

It’s far easier if you can get documentation of the protocol. If you do need to reverse engineer the USB protocol, here are some tools that might help: Windows tools: let you do actions with your device and log the stream of USB information going downstream/outbound to the device, or upstream/inbound back to your computer. Is a variant of the same code that evidently has some improvements. It appears that the preferred location for Snoopy Pro is. Linux tools: – The previously mentioned will show you devices that are currently plugged in. – The usbutils package includes a bunch of handy console tools for USB, including lsusb, which shows you the USB devices that are currently plugged in.

The output of lsusb looks like this: Bus 001 Device 006: ID 2222:3061 MacAlly Bus 001 Device 002: ID 0557:7000 ATEN International Co., Ltd Bus 001 Device 003: ID 045e:00db Microsoft Corp. Write the driver. – It seems that the process of writing drivers in Linux is getting easier over time. The has documented this well. Compare this by Greg Kroah-Hartman to Greg’s on controlling a simple USB lamp device.

Linux Kernel Mailing List Archive

Then see Greg’s follow-up article on. It turns out that you can use the to read/write with USB devices without ever mucking around in the kernel. This is possible because Linux provides a USB filesystem (called USBFS) that automatically mounts USB devices into the Linux directory tree. Note that libusb also works on BSDs, Mac/OSX computers, and that there is a. If you really want to delve into this deeply, there’s an O’Reilly book on that you can buy as well.