From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4DFE038F.202@domain.hid> Date: Sun, 19 Jun 2011 16:11:27 +0200 From: Gilles Chanteperdrix MIME-Version: 1.0 References: <4DFDF79F.1090502@domain.hid> <4DFDFD2F.1080506@domain.hid> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-help] Problem accesing I2C without using Linux kernel List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Andrey Nechypurenko Cc: Xenomai help On 06/19/2011 04:06 PM, Andrey Nechypurenko wrote: >> Note that this mailing list is probably not the best place to ask your >> question, since we mostly talk about Xenomai here, and your issue does >> not seem to have anything to do with Xenomai. > > I understand. Do you have an idea what list might be more appropriate > for it? I did also post the same question to the BeagleBoard mail > list. Ok, maybe you will get better support there. There may also be some IRC channel somewhere, where you can get a more interactive help. >> Second stupid questions: are you sure all the clocks needed to get that >> I2C module running are enabled? > > The module works. I think kernel configured it properly because I can > use user space utility for example i2cdetect and see my sensors > detected on the bus. At the moment where I was trying to read the > status I did not made any reconfiguration before. So my assumption was > that the module is already configured properly and at least an attempt > to read the status should succede. To be sure of that, you would have to be sure that the clocks are not disabled when the device is not opened. To check this, either check the kernel sources, or try and open the i2c device, and keep it open before you mmap /dev/mem -- Gilles.