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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 63A65C77B7E for ; Thu, 25 May 2023 14:35:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241654AbjEYOfi (ORCPT ); Thu, 25 May 2023 10:35:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233825AbjEYOfh (ORCPT ); Thu, 25 May 2023 10:35:37 -0400 Received: from mail-vk1-xa2f.google.com (mail-vk1-xa2f.google.com [IPv6:2607:f8b0:4864:20::a2f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C123187 for ; Thu, 25 May 2023 07:35:35 -0700 (PDT) Received: by mail-vk1-xa2f.google.com with SMTP id 71dfb90a1353d-456d9652c24so418734e0c.1 for ; Thu, 25 May 2023 07:35:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bgdev-pl.20221208.gappssmtp.com; s=20221208; t=1685025334; x=1687617334; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=aAogn6dT4b6m8+lLJAd5XLZlUe3QdLu7einTf1A+tIg=; b=olneRNt0QSWwgjhhvV/O7lXmLW+2Z9uuG9ZKZc988z4Tl6cH95KQuo0n9C0Ybbxv7D U9Z6WWaeCLzdQMhyJBfm/h5TCWirx+agFmWwI96Hc0meNcwmmStEpY/yK37l0uNrv/LD VHYKX9atO0lsz8JGcgKcNiUk0910Ur0BIRugXfF6zSXQ3K50r7sBcnfLjJW3gh5Vr4cU SQkVBc6E2nGiw84gGkHHYv4BwVcs9XLkjUHibjOFvAUQgTGL+Jwups8nyiSmG53GnFvJ oZIxh+UkuTiyo2kcpmHPYCEENHva6DjmbQafvJdNE1FhZmev/U/RnKJcJMNfLCZDHpIS 5bnA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1685025334; x=1687617334; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=aAogn6dT4b6m8+lLJAd5XLZlUe3QdLu7einTf1A+tIg=; b=OztOvGaoRZ8LXG9Fz4BmUbB3SIzvTNqj2oAX9410iYIXAagyfnP4w5kKI8mpr+ZsVT qH8O03btmcnKT1UUmIz3alQGUb5G/I7VKidP1fzQVdyyTcm9bz0Cn6Sh3d4KZqauGAx1 Ph2D8YopkH5TiuY0Jq6TWvYT4oYlAXlUI+0h3IA1cKYtNzP+P8FBF8lRMLXEntTITjC3 Ug6XOm2fvWGX+f5MmVcFBpLIsZlI02sBaWsbYDnBS4YaqTW2ZDtLG6VEkt2vHNx5DCCX Kt2ajbEn+x4BR3XzHXQ552BomGXIHU42KTVAd+ga0m7yIx/22LLs+0jq/qUqSAjl0MH/ 8n1Q== X-Gm-Message-State: AC+VfDzf3h/ZTDj1Uba5l8jZ3e0t3cgGEjOBdvoe7SE2F4PgwDT8rOfW 1Lzlp3sdapZS2F7Z3VKD5pvHO6qQz4M6uubN8KgDQg== X-Google-Smtp-Source: ACHHUZ4qjNa/T2reNQHamvgq/FN+8eYf30P46YnDIhAQfq41TQFW6fcyaVASyBQ7p8xhGwBSUypu5WGUmvNEbQxN824= X-Received: by 2002:a05:6122:141:b0:457:56a4:19e7 with SMTP id r1-20020a056122014100b0045756a419e7mr1164313vko.0.1685025334463; Thu, 25 May 2023 07:35:34 -0700 (PDT) MIME-Version: 1.0 References: <72990baf-6964-01ad-d891-7090831d0310@alliedtelesis.co.nz> In-Reply-To: From: Bartosz Golaszewski Date: Thu, 25 May 2023 16:35:23 +0200 Message-ID: Subject: Re: using libgpiod to replace sysfs ABI (was Re: [PATCH] gpiolib: Avoid side effects in gpio_is_visible()) To: Andy Shevchenko Cc: Chris Packham , Kent Gibson , "linux-gpio@vger.kernel.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org On Thu, May 25, 2023 at 11:13=E2=80=AFAM Andy Shevchenko wrote: > > On Thu, May 25, 2023 at 2:53=E2=80=AFAM Chris Packham > wrote: > > On 24/05/23 17:41, Kent Gibson wrote: > > ... > > > It'd also be great if there was some way of ensuring that a line's stat= e > > is kept after the application has released the request (i.e. the txdis > > case I mentioned). But that probably needs work on the kernel side to > > make such guarantees. > > Won't happen. It will require too much of strictness to be added into > the kernel with likely breakage of the existing code and > documentation. What is being discussed is a D-Bus (like?) daemon + > Policy in user space that will allow user / process / cgroup / etc to > "own" the line and track its state. > It's already WiP[1]. I'm trying to keep the footprint minimal with only GLib and dbus required at run-time. Bart [1] https://github.com/brgl/libgpiod-private/tree/topic/dbus