From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 57EFB19BDC for ; Mon, 23 Oct 2023 14:19:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=arndb.de header.i=@arndb.de header.b="lYc+ZBHk"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="niRJqeL+" Received: from out1-smtp.messagingengine.com (out1-smtp.messagingengine.com [66.111.4.25]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CC950100; Mon, 23 Oct 2023 07:19:54 -0700 (PDT) Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailout.nyi.internal (Postfix) with ESMTP id 319375C033F; Mon, 23 Oct 2023 10:19:54 -0400 (EDT) Received: from imap51 ([10.202.2.101]) by compute5.internal (MEProxy); Mon, 23 Oct 2023 10:19:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arndb.de; h=cc :cc:content-type:content-type:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:sender :subject:subject:to:to; s=fm2; t=1698070794; x=1698157194; bh=bs mBsb2C4biRFAK90R3YGndrC+6bsEOQQxqfzZ99ePQ=; b=lYc+ZBHk7xNLUtCtBW SW8wU5/knar6IJPqYjl2CJlJp3v6LY9kHkC/0Zfhp+3PTywtBVWdAqtC05b7Pbzr U0hz2+5uHYYsZS0NY32+N1gtTXo4aD7GNYc1rbazGdO0kyURlMQBaEirGbvxkG9d SIAW0ZhuyzLDXAtskzdjRZxeHE7ttbI9ALKzJf0d6CeVwc9wvatHsle+gWRH4fVb 55FuhknZOFv5PHK4IK8rzARimnoff+PJPTeyjyIM0mWIRxMmzFwWahsJ2ZRGVauV bOxKJuyw7zaSXKFAOCRJlzcHn9kWaL7DG1uRb2N9IQr83vl3yqUJiLntZnkFkXjF tfTg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:content-type:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm3; t=1698070794; x=1698157194; bh=bsmBsb2C4biRF AK90R3YGndrC+6bsEOQQxqfzZ99ePQ=; b=niRJqeL+BF+kNPZQvaQPd/1+q2SwC 69sqEW1ElhXcqkiS2L7UGVNTaxU+nsD5f0wrk/AX8LHVxxVBnJnQSNwuKytXPxt2 z7m3Hg++LJW/fAsDZj01KzRe4fZNimddMbymzw69rCMe5pVjfRD1VGtoqXlhUwYX M82mbZRNauf5OBlCi9+V9Bbao1ZWLMekUgh7l1pUm6uKWjtg6u2JhkNnfvOiBkE1 8YioQ8s2B9pAvNmz5GZwg5JALdw67TAToo8hKHBX58mE4e6httVe8fqF3V9uNVde xEQskAu0dFh408H21biJ8MxBRlaRvv0kmYld0GqBk3mKPnBHvJORtg9Rw== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvkedrkeeigdejfecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefofgggkfgjfhffhffvvefutgesthdtredtreertdenucfhrhhomhepfdetrhhn ugcuuegvrhhgmhgrnhhnfdcuoegrrhhnugesrghrnhgusgdruggvqeenucggtffrrghtth gvrhhnpeevhfffledtgeehfeffhfdtgedvheejtdfgkeeuvefgudffteettdekkeeufeeh udenucffohhmrghinhepkhgvrhhnvghlrdhorhhgnecuvehluhhsthgvrhfuihiivgeptd enucfrrghrrghmpehmrghilhhfrhhomheprghrnhgusegrrhhnuggsrdguvg X-ME-Proxy: Feedback-ID: i56a14606:Fastmail Received: by mailuser.nyi.internal (Postfix, from userid 501) id DCB18B60089; Mon, 23 Oct 2023 10:19:53 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface User-Agent: Cyrus-JMAP/3.9.0-alpha0-1048-g9229b632c5-fm-20231019.001-g9229b632 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <15f25d73-32d5-4809-8096-32c856559d66@app.fastmail.com> In-Reply-To: References: <20231019125646.14236-1-eliza.balas@analog.com> <20231019125646.14236-3-eliza.balas@analog.com> <2023101917-cork-numeric-dab8@gregkh> <2023102030-resort-glance-57ef@gregkh> <2023102339-outcast-scone-5a63@gregkh> Date: Mon, 23 Oct 2023 16:19:32 +0200 From: "Arnd Bergmann" To: "Eliza Balas" , "Greg Kroah-Hartman" Cc: "linux-kernel@vger.kernel.org" , "devicetree@vger.kernel.org" , "Rob Herring" , "Krzysztof Kozlowski" , "Conor Dooley" , "derek.kiernan@amd.com" , "dragan.cvetic@amd.com" , "Jonathan Cameron" , "Lars-Peter Clausen" , linux-iio@vger.kernel.org Subject: Re: [PATCH v3 2/2] drivers: misc: adi-axi-tdd: Add TDD engine Content-Type: text/plain On Mon, Oct 23, 2023, at 15:30, Balas, Eliza wrote: >> -----Original Message----- >> Cvetic ; Arnd Bergmann >> Subject: Re: [PATCH v3 2/2] drivers: misc: adi-axi-tdd: Add TDD engine >> > > > Since the device is not an iio device, using an iio function would be confusing. >> > > >> > > Why isn't this an iio device? >> > >> > The device is not registered into the IIO device tree, >> > and does not rely on IIO kernel APIs. >> > Even though there are a few attributes that resemble the >> > ones from iio, and the sysfs structure is similar, >> > this is not an IIO device. >> > In the previous patch versions 1 and 2 we concluded >> > that this device fits better in the misc subsystem. >> >> Ok, can you point to that in the changelog where the IIO maintainer >> agreed that this doesn't fit into that subsystem? >> > This was one of the discussions from previous v2 : > https://lore.kernel.org/all/5b6318f16799e6e2575fe541e83e42e0afebe6cf.camel@gmail.com/ > > I will add it to the changelog the next time I submit the patches. It sounds like Jonathan wasn't quite sure either here, and I would still argue (as I did in that thread), that drivers/iio is probably a better option than drivers/misc. In particular, you mention that you actually make this device appear as an IIO device to user space using the "iio-fake" hack. I can see that IIO is not a perfect fit if this is the only device of its kind, but going that way anyway avoids a number of problems by reusing infrastructure for the IIO ABI and serialization with in-kernel users, as well as giving you the option of adding other compatible drivers later. Arnd