Linux device drivers

Penguin01 · 12-02-2009, 07:34 AM

Does anybody know where I can get the source code for a USB mass storage device driver for Linux?
I have been trying to search for it, but have had no luck.
I would have thought it would be easy as Linux is opensource.

raju.mopidevi · 12-02-2009, 07:45 AM

This link may be helpful for you . Click here

raju.mopidevi · 12-02-2009, 07:58 AM

to know how to write USB driver code , follow this

Penguin01 · 12-02-2009, 08:27 AM

Thanks for your reply.
Does this mean that there is no current source code for a USB mass storage device that can be downloaded and modified?
I want to try and understand how USB device drivers read and write.

sundialsvcs · 12-02-2009, 08:29 AM

Of course there are.

/usr/src/linux/drivers/usb/usb_skeleton.c is a great start.

It is pretty much de rigeur that the proper way to approach this sort of thing is to look at "prior art." Find something that is very-close to what you are doing and adapt it ... or, quite likely, discover that you actually don't have to. If your purpose is simply to discover how something works: "Use the Source, Luke!"

Penguin01 · 12-03-2009, 09:26 AM

Thanks.
I am running the 2.6.28 kernel and when I try and compile a basic "Hello World" device driver. When I try to compile it I get "cannot find module.h".
I have read that I may need to enter the following command

$ sudo apt-get install module-assistant

But this just says "E: Couldn't find package module assistant."

Does anyone know what the problem is and how I can fix it?

raju.mopidevi · 12-03-2009, 10:04 AM

which distribution you are using ? is it debian based ?

Penguin01 · 12-04-2009, 04:36 AM

Yes it is debian based (as far as I am aware). Is there anyway of checking what the distribution? I am running Ubuntu.

raju.mopidevi · 12-04-2009, 07:22 AM

Edit /etc/apt/sources.list (you need to be root to do this).
In there somewhere there should be lines that look
more or less like this:
Code:

Code:

deb http://archive.ubuntu.com/ubuntu/ breezy  universe
deb-src http://archive.ubuntu.com/ubuntu/ breezy universe

They may say dapper if you are using a Dapper release, and the archive
URL may be slightly different, might have us or ca or eu or something in it.

Then in a terminal do
Code:

Code:

sudo apt-get update

or in Synaptic, select the Reload button.

Penguin01 · 12-04-2009, 03:26 PM

I am using:
Linux version 2.6.28-11-generic (buildd@palmer) (gcc version 4.3.3 (Ubuntu 4.3.3-5ubuntu4) ) #42-Ubuntu SMP

When I open the sources.list file I have:
deb http://gb.archive.ubuntu.com/ubuntu/ jaunty universe
deb-src http://gb.archive.ubuntu.com/ubuntu/ jaunty universe

I tried:
sudo apt-get update
This seems to run fine, but again when running gcc -c hello.c as on http://www.freeos.com/articles/2677/
I get:
hello.c:2:26: error: linux/module.h: No such file or directory

Please help, Thanks.

Penguin01 · 12-04-2009, 04:27 PM

So after restarting my machine and following http://linuxdevcenter.com/pub/a/linu...ux.html?page=2 instead, the Hello World device driver works!!!

Does 'sudo apt-get update' command compile the kernel? As it is very different to '$ sudo apt-get install module-assistant'

Thanks for your help raju, now I'll try the usb-skeleton.c.

raju.mopidevi · 12-04-2009, 07:05 PM

Quote:

Originally Posted by Penguin01

Does 'sudo apt-get update' command compile the kernel?

"$sudo apt-get update" is designed for package management, and software updating.
Passing the update argument to the Apt-Get command results in a system update process. This process will contact the configured repositories and compare them to existing files on the local system. If an update is possible, the “sudo apt-get upgrade” command will process the respective program upgrade.

Penguin01 · 12-07-2009, 02:42 PM

I have been looking at the usb-skeleton.c code.
I got this code from http://lxr.free-electrons.com/source...ton.c?v=2.6.28, as it is supposed to be in linux/drivers/usb but I cannot seem to find it on my ubuntu machine.

From what I know, the code from the site above seems to be OK, but the only confusing thing is that the device gets registered at the end, rather than the beginning.
Is this correct? As I thought the first thing that happens is the device is registered???
Can someone please verify if the usb-skeleton.c is correct for USB mass storage devices...

Thanks.