blog.felipebalbi.com

Hi all,

Let's take a look at the brand new, yet-to-be-merged USB Composite Gadget Framework.

The framework was introduced by Linux USB Developer David Brownell and, thanks to his great work, we're gonna be able to reuse what we now call usb function drivers into another entities, combining them to create a usb composite gadget.

Quoting Dave himself:

We want to split most of the current gadget drivers into reusable/combinable "usb_function" entities, making it easier to set up composite and multi-configuration gadgets.

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Hello all,

Finally musb/tusb driver is going to mainline

We still have a few stuff to fix and I'm taking care of that but we're planning to push it to release 2.6.26 :-). From the day musb gets merged to mainline, the main development of it will be moved from linux-omap to linux-usb mailing list, which will allow more usb gurus to review the patches.

Most likely the driver will get more and more improvements.

Again,

Thanks to everybody that have been helping musb so far. Here's a git shortlog of those who have been helping us:

1 Alan Stern
2 Anand Gadiyar
2 Andrzej Zaborowski
4 Bryan Wu
51 David Brownell
5 Dirk Behme
28 Felipe Balbi
2 Hunyue Yau
7 Kevin Hilman
182 Tony Lindgren
3 Vikram Pandita

Please follow this thread in linux-usb mailing list for more details.

Sometimes we have to send patch series and it's always useful to add a cover letter (or cover email) explaining what your series is implementing/fixing.

Newest git (currently only on git's git tree) provides a new format-patch option to generate the cover leter for you. In the cover leter git adds shortlog and diffstat, you only need to change the subject and mail body.

It's as simple as:

 
$ git format-patch -o directory -n --cover-letter $commit1..$commit2

After that take a look at directory/0000-* and change what's necessary

Creating several ssh accounts for allowing push access to developers on a project is, at least, a waste of time and a possible security hole.

Instead of that, let's see how to manage such users using only one user "git" and several ssh-keys for allowing such push access.

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Building an arm-cross-gnu-toolchain can be somewhat painful. I'm posting here how I could achieve this after reading lots of documents over the web.

This will be helping me keeping up-to-date with binutils and gcc versions when building arm kernels

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Housekeeping a git repository is useful to make it smaller and faster. Git has a lot of tools to allow you optimizing your git repository. Let's take a look on a few of them and see what they do.

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U-boot is an open source bootloader. This post is here because I had a problem with U-boot where I couldn't update it using ethernet.

It's not that difficult to use serial line for u-boot upgrading, as long as you have a "working" u-boot flashed in your board, you can always use loady or loadb to download binary image into your board's RAM.

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ARM is an architecture 32-bit RISC based. Which means you have to always load values to its internal registers before working with those values.

Also, it expects data access to be 32-bit aligned. Unaligned access in ARM aren't denied, but causes extra overhead on code execution.

On this first part of this series, we'll see that int variables (or any variation of 32-bit variables) are the best choice when declaring local variables in functions that'll run on ARM processor cores.

We assume you're familiar with C programming language and can read ARM assembly code.

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Hello all,

When dealing with wireless communications we must protect our information by using cryptographic techniques. UWB is not different from any other wireless connection and we must take care of its security as well. There are already a bunch of cryptographic algorithms out there but which algorithm was chosen to be used with UWB ? Is it fast and secure enough ? Let's take a look at UWB Security features.

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We already discussed a bit about it and we know this is a feature to allow role switching in otg sessions without changing the cable. But what does this really mean? Who handle this? Which device(s) already support it? How should I know that my device supports HNP? Is there any public code for that?

That's what we're taking a look today. Take a look by clicking at the next link

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