www.8devices.com
|
|
Carambola2 I2S and MBOX (DMA)
Author |
Message |
jpc
Joined: 10 Sep 2013, 13:21 Posts: 5
|
I am interested in writing a driver for the I2S interface but unfortunately even the full datasheet that is circulating on the internet is a bit light on the details on how the "MBOX" DMA subsystem should be set up. Unfortunately DMA looks like the only way to actually do any I2S transfers.
Does anyone has access to the AR9331 SDK or any example code from Atheros? Of course I can sign an NDA if this is what it takes.
|
10 Sep 2013, 13:43 |
|
|
FPeter
Joined: 21 Aug 2013, 21:21 Posts: 101
|
|
10 Sep 2013, 14:16 |
|
|
Socrates
Joined: 25 Oct 2012, 13:37 Posts: 30 Location: Kaunas, Lithuania
|
There's a source code taken out from SDK, however it only can be used as a reference for Your own driver writing, because the driver is not ALSA compatible.
|
11 Sep 2013, 07:05 |
|
|
jpc
Joined: 10 Sep 2013, 13:21 Posts: 5
|
I am thinking of two things I would like to do with this and for the first "experiment" I don't need ALSA. But I am pretty sure I can also handle rewriting it for the ALSA framework. I am only started doing kernel development recently but I have plenty of both embedded and Linux/OS X user-space programming experience.
Would it be possible for me to get said source code fragments from you?
|
11 Sep 2013, 08:30 |
|
|
Socrates
Joined: 25 Oct 2012, 13:37 Posts: 30 Location: Kaunas, Lithuania
|
|
11 Sep 2013, 10:41 |
|
|
jpc
Joined: 10 Sep 2013, 13:21 Posts: 5
|
Thank you very much.
|
11 Sep 2013, 11:43 |
|
|
FPeter
Joined: 21 Aug 2013, 21:21 Posts: 101
|
|
11 Sep 2013, 11:48 |
|
|
Socrates
Joined: 25 Oct 2012, 13:37 Posts: 30 Location: Kaunas, Lithuania
|
|
11 Sep 2013, 12:21 |
|
|
jpc
Joined: 10 Sep 2013, 13:21 Posts: 5
|
Socrates: I went through the code today and unfortunately it looks like it was made for other Atheros chips (the Virian board with the AR7241 processor and the Wasp board with the ar934x SoC). It should be possible to reverse engineer the missing parts using the datasheet but it's a pity this won't work as is. I found some additional files in the Fritzbox GPL source releases: http://gpl.back2roots.org/source/fritzb ... ps/ar7240/http://gpl.back2roots.org/source/fritzb ... ch-ar7240/They have header files (and even some function implementations) for the AR933x SoC.
|
12 Sep 2013, 19:32 |
|
|
Socrates
Joined: 25 Oct 2012, 13:37 Posts: 30 Location: Kaunas, Lithuania
|
I believe the peripheral is almost the same. It should be possible to write a driver using those files as reference.
|
13 Sep 2013, 05:37 |
|
|
Who is online |
Users browsing this forum: No registered users |
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot post attachments in this forum
|
|