From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933307AbdABOhO (ORCPT ); Mon, 2 Jan 2017 09:37:14 -0500 Received: from lelnx194.ext.ti.com ([198.47.27.80]:38021 "EHLO lelnx194.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933062AbdABOhN (ORCPT ); Mon, 2 Jan 2017 09:37:13 -0500 Subject: Re: Nokia N900 sound driver and ECI GPIOs To: =?UTF-8?Q?Pali_Roh=c3=a1r?= References: <201701012054.54505@pali> <20170101223639.GA13868@amd> <20170102085150.GB6728@pali> <20170102125840.GD6728@pali> CC: Pavel Machek , Jarkko Nikula , Tony Lindgren , Eduardo Valentin , Lars-Peter Clausen , Aaro Koskinen , Nishanth Menon , Sebastian Reichel , Ivaylo Dimitrov , joerg Reisenweber , , From: Peter Ujfalusi Message-ID: Date: Mon, 2 Jan 2017 16:36:38 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <20170102125840.GD6728@pali> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/02/2017 02:58 PM, Pali Rohár wrote: > On Monday 02 January 2017 14:53:44 Peter Ujfalusi wrote: >> On 01/02/2017 10:51 AM, Pali Rohár wrote: >>> On Monday 02 January 2017 10:34:34 Peter Ujfalusi wrote: >>>> On 01/02/2017 12:36 AM, Pavel Machek wrote: >>>>> Are there multi-button headsets compatible with N900? >>>> >>>> Not sure if n900 is capable of handling ECI communication, n9 was. In n9 >>>> the PMIC/Audio chip had an ECI core integrated afaik >>> >>> In N9 it is handled by twl5030 chip? Is there documentation for that >>> ECI/ACI part? N900 has twl4030 so we need some chip documentation for >>> adding support for N900... >> >> n9 has twl5031 and the documentation is not public. But the kernel >> source from Nokia have the driver under drivers/mfd/twl5031-aci.c It is >> using the ECI stack to report the changes. >> twl4030 and twl5030 does not have support for ECI, only twl5031. > > Ok, so Nokia N900's audio chip (twl4030) does not have support for ECI. TLV320AIC34 (two of them) on n900 to be precise, n9 uses twl5031 and tlv320dac33. > But still as Jarkko wrote there could be an option to supports ECI via > GPIO and ADC. Yes, there is the option, but w/o documentation on the ECI protocol it is not going to be easy. And I'm sure there were a (good) reason the n900 does not support ECI. If it could be done in a stable way the product would have support for it. > And there is still mysterious gpio 178 (RX51_ECI_SWITCH_1_GPIO) which > could help us? Yeah, that is something I have no idea what it is for. It could be that the schema is using different pin mode for it? It might worth looking at the TRM on which pin the gpio_178 can go out and look for the possible modes? Most likely waste of time... > -- Péter