From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-out-148.synserver.de ([212.40.185.148]:1098 "EHLO smtp-out-148.synserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755556Ab3B0Qct (ORCPT ); Wed, 27 Feb 2013 11:32:49 -0500 Message-ID: <512E3592.4020702@metafoo.de> Date: Wed, 27 Feb 2013 17:34:26 +0100 From: Lars-Peter Clausen MIME-Version: 1.0 To: Chris Micali CC: "linux-iio@vger.kernel.org" Subject: Re: IIO Drivers References: <26387F1A648A4D3D9BB4142C4F0AAE98@gmail.com> <512E2F31.8000604@metafoo.de> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 02/27/2013 05:21 PM, Chris Micali wrote: > Hi Lars, > Thanks a lot for getting back to me. I've attached my code - it's pretty simple, I just copied an existing driver. As I mentioned individual reads are working fine (if i cat in_voltage0_raw) but buffered reads are failing. I've tracked the issue to industrialio-buffer.c in iio_compute_scan_bytes() which always returns zero because, i believe, the mask is 0. I haven't been able to find any docs on what 'scan masks' mean but I have seen a few drivers that supply available scan masks. Should I be specifying scan masks? > Thanks! > -chris Hi Chris, You need to enable the channels you want to sample in sysfs. If you are using the command server you can for example do this by doing a 'write ads... scan_elements/in_voltage0_en' - Lars > > > On Wednesday, February 27, 2013 at 11:07 AM, Lars-Peter Clausen wrote: > >> On 02/26/2013 08:56 PM, Chris Micali wrote: >>> Hello Lars, >>> >>> I'm doing a bit of hacking on a IIO driver based on some of your drivers on a 3.8 kernel (specifically writing a driver for a TI SPI adc.) I've been able to get a driver up and working such that I can read directly from the in_voltage0_raw on sysfs and get the correct values but I can't seem to get buffered access working (via iio_cmdsrv.) I've had a hard time finding any docs on this stuff and I was wondering if you could give me any pointers on where to look or who else perhaps to ask about this stuff? Any pointers would be very much appreciated! >>> >>> Thanks, >>> Chris >> >> >> >> Hi, >> >> I'm afraid except for the the documentation in >> drivers/staging/iio/Documentation/, the kernel doc comments and the skeleton >> driver (drivers/staging/iio/iio_simple_dummy*) there is not much additional >> documentation available. >> >> The general place to ask questions about IIO is the IIO mailinglist. I've >> put it on CC, hope you don't mind. >> >> I think we can help you best if you post your code. >> >> - Lars