From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88E18C433EF for ; Wed, 22 Sep 2021 12:44:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 694E1610A0 for ; Wed, 22 Sep 2021 12:44:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235781AbhIVMqL (ORCPT ); Wed, 22 Sep 2021 08:46:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60092 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235227AbhIVMqL (ORCPT ); Wed, 22 Sep 2021 08:46:11 -0400 Received: from mail-lf1-x12b.google.com (mail-lf1-x12b.google.com [IPv6:2a00:1450:4864:20::12b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E0DC2C061574 for ; Wed, 22 Sep 2021 05:44:40 -0700 (PDT) Received: by mail-lf1-x12b.google.com with SMTP id i4so11489779lfv.4 for ; Wed, 22 Sep 2021 05:44:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=N6zy0XIQ/Ot4nV1fJewZ2Mzh0jnz4dCBiZEPZp+vzwQ=; b=GxpOln0iQ5Taha7w32msAJiU4luYcrITT/LN6seEyswmjNzyw6cv5oSOaN2/wNenS6 T/9fi83cFyfkQWytSKxvrKdOae5Ri078OzMtMFfnDGoYPb1b3MPU2JV2bDsJt/d0D4RF 6unz0EbCdsoEpdk1TJrcoeEwNK1x9kF4Wmi+i6YWSdhgihewwPxQuk1VPkVp2llPbE3U T5merrcMAj3Z61ROwocwHcwh5nO4zHzyokywNuIg+vz3uZ1cOPD4V6Z7OD3AePNi3PKB HyRFXy6RZG41PLgOFvGG2/faKXwHPWM5Ih4VPz7MvEu2r/LNUyWSvu8Nsa3kxkoWaklF TmMg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=N6zy0XIQ/Ot4nV1fJewZ2Mzh0jnz4dCBiZEPZp+vzwQ=; b=rDRi0r23f/Fw5McoVbJDPiNwuveccTrWVjvbyhZ9orWGkFi6xFBa/6fXpU9ZkU166U tmqUyrETl9KP+xJFTBJcAE2RBaAQrQ16TI9V/inkuayE4kp8jOamd1sOnxajXra+uuaQ YocBgj1dgM/mavGhmLTBhRKH5wrXkWcQTcGEmvXYcsinWEaPjyX+9lQy1M6qRT9QXMwl h+C/T1/nMXGkWH2IIYtw5/THBiGb2OYh7zaIeGU0Y8itzfX5XcVVJqFXsx9ohdwVpsfk 98E+nviFwTWHlAMyigCVPyea3lE4vs6ju3GsLFP5MxsC1YkGBrOz71Y97XJgL/ewkktJ g9OQ== X-Gm-Message-State: AOAM531bdJ9BTJJN24iKK+XTq7j3KxBmthVeUFd7BDb6gGcQcUNTVAYX rgaUbLcRIPThXPNd/4e0oz+DUcjuDPqg2Ei0XfOEWSUfs8s= X-Google-Smtp-Source: ABdhPJw7wBjZWopnAvqKnwuEsD6KIR6co3Aq2dOcWaemKGQoVnAEgHb/DVfCQEdGKj6rsIMEQpAn4m13TjIv+SVmrJA= X-Received: by 2002:a2e:9942:: with SMTP id r2mr34931266ljj.92.1632314679248; Wed, 22 Sep 2021 05:44:39 -0700 (PDT) MIME-Version: 1.0 References: <74f1974b-ac08-96f1-887e-99580a2bf212@axentia.se> In-Reply-To: From: Fabio Estevam Date: Wed, 22 Sep 2021 09:44:28 -0300 Message-ID: Subject: Re: Reading ADC that comes from a multiplexer To: Peter Rosin Cc: linux-iio@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Wed, Sep 22, 2021 at 8:37 AM Fabio Estevam wrote: > > Hi Peter, > > On Wed, Sep 22, 2021 at 4:27 AM Peter Rosin wrote: > > > Basically, the whole point is that you simply don't. The iio-mux exposes > > the channels as 8 new ADCs, and whenever you read a value from one of > > them, the iio-mux operates the gpios for you, giving you the impression > > that you have 8 independet ADCs. They are of course not independent, but... > > Thanks for the clarification. It was helpful. > > > That's exposed to user-space as: > > > > $ ls "/sys/bus/iio/devices/iio:device3" > > in_altvoltage2_compare_interval in_altvoltage5_scale > > in_altvoltage2_invert in_altvoltage6_compare_interval > > in_altvoltage2_raw in_altvoltage6_invert > > in_altvoltage2_scale in_altvoltage6_raw > > in_altvoltage3_compare_interval in_altvoltage6_scale > > in_altvoltage3_invert in_altvoltage7_compare_interval > > in_altvoltage3_raw in_altvoltage7_invert > > in_altvoltage3_scale in_altvoltage7_raw > > in_altvoltage4_compare_interval in_altvoltage7_scale > > in_altvoltage4_invert name > > in_altvoltage4_raw of_node > > in_altvoltage4_scale power > > in_altvoltage5_compare_interval subsystem > > in_altvoltage5_invert uevent > > in_altvoltage5_raw > > $ cat "/sys/bus/iio/devices/iio:device3/name" > > envelope-detector-mux > > Ah, so that's my issue then. I don't see a new device inside > /sys/bus/iio/devices/. > > I only see the original stmpe ADC: > > ls "/sys/bus/iio/devices/iio:device0" > dev in_voltage5_raw in_voltage_scale power > in_temp8_input in_voltage6_raw name subsystem > in_voltage4_raw in_voltage7_raw of_node uevent > > Maybe my dts is not correct to make the mux appear under > /sys/bus/iio/devices/iio:device1. Just realized that iio-mux.c does not get probed. In mux_probe(): parent = devm_iio_channel_get(dev, "parent"); is always returning -EPROBE_DEFER, even though I passed: io-channel-names = "parent";