From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-out-230.synserver.de ([212.40.185.230]:1099 "EHLO smtp-out-230.synserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751053AbaKZKHi (ORCPT ); Wed, 26 Nov 2014 05:07:38 -0500 Message-ID: <5475A66C.2090204@metafoo.de> Date: Wed, 26 Nov 2014 11:07:40 +0100 From: Lars-Peter Clausen MIME-Version: 1.0 To: Mike Looijmans , pmeerw@pmeerw.net CC: "linux-iio@vger.kernel.org" Subject: Re: iio:adc:ad799x driver broken after commit "Write default config on probe and reset alert status on probe" References: <547439F9.7070903@topic.nl> <54748C48.1090608@metafoo.de> <5475A1A0.5060003@topic.nl> In-Reply-To: <5475A1A0.5060003@topic.nl> Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 11/26/2014 10:47 AM, Mike Looijmans wrote: > On 11/25/2014 03:03 PM, Lars-Peter Clausen wrote: >> On 11/25/2014 09:12 AM, Mike Looijmans wrote: >>> After this commit: >>> >>> iio:adc:ad799x: Write default config on probe and reset alert status on >>> probe >>> >>> writing ALERT_EN and BUSY_ALERT to the chip config register clears >>> pending alerts, BUSY_ALERT is cleared when reading back the register >>> >>> The AD7999 on our board no longer functions, reading the in_voltage*_raw >>> sysfiles always returns "255" after this. >>> >>> I reverted the commit, and that fixed the problem for me. >> >> I suspect that there is something going wrong when reading back the config >> register, can you check the attached patch and see what the output is? >> >> Thanks, >> - Lars >> > > The attached patch delivered the following output (using the current head > code): > > ad799x 1-0029: config: b 0 > Yea, kind of what I expected based on your description. Looking at the datasheet it seems the ad7999 doesn't even support register read back which would explain the issue. I'll try to find a board and see if I can fix it. - Lars