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 CBEE2EB64D7 for ; Tue, 20 Jun 2023 10:06:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231751AbjFTKGN (ORCPT ); Tue, 20 Jun 2023 06:06:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39346 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231812AbjFTKFt (ORCPT ); Tue, 20 Jun 2023 06:05:49 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4FCE91AC; Tue, 20 Jun 2023 03:05:32 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C106661193; Tue, 20 Jun 2023 10:05:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2CA59C433C9; Tue, 20 Jun 2023 10:05:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1687255531; bh=vc5WlVlGI94okyigrFf0d+GSybFc03mLe2FWiiXr8N0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=sddhdzg2AhtXOX2BNswSTh047C+vw9hNecLzglmn1TpZi9ZIiK9ocqIu4pRfUM3Xj bVwHX9pEykboXk/Oqllb3Mmr9AwMLuFWpbC1QL4ohgeWHuIgXPstMLe6vOp8q4J1mH f+4/Dxq9YAqg8GdgHonl8n3IDPWtFo9Dn36eTA3eai/DOvUCg8U1EW4SjgDg0NigCG Fkpm/Vsly5A7K+wHG/wMBAefevtdl0a/1xqkOGH8GAa/kXPpLMqrhj4KvCbvYlHIL5 XZ3IXxDX9Fen5aA5uGl6Y706YeZw/kj9cr6uBj+bmn2mxKH3EEZlLRw0TBfizniERA ac7vKTEAnEWnA== Received: from johan by xi.lan with local (Exim 4.94.2) (envelope-from ) id 1qBYEt-00080a-8T; Tue, 20 Jun 2023 12:05:31 +0200 Date: Tue, 20 Jun 2023 12:05:31 +0200 From: Johan Hovold To: Wolfram Sang Cc: linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 4/5] gnss: ubx: add support for the reset gpio Message-ID: References: <20230523064310.3005-1-wsa+renesas@sang-engineering.com> <20230523064310.3005-5-wsa+renesas@sang-engineering.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="Q/yN9VCYAD/fgz9L" Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org --Q/yN9VCYAD/fgz9L Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Jun 20, 2023 at 11:41:39AM +0200, Wolfram Sang wrote: >=20 > > But can you elaborate on the "disappearing" bit? How exactly does it > > "disappear" when the gnss0 device is *not* opened? >=20 > When you send an I2C message with the address of the device, it usually > ACKs it to say "Hi, I am here". When the ublox device is in reset state, > it does not ACK its address. So, tools like "i2cdetect" will not report > the device as "someone is listening there". Ah, ok, so you used it to verify that reset is working as intended. Rereading the commit message now it makes more sense, I guess I was thrown off by the reference to I2C. Perhaps adding a sentence or two about the alternate interface and using it as a means of verification would make things a bit more clear. Johan --Q/yN9VCYAD/fgz9L Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQQHbPq+cpGvN/peuzMLxc3C7H1lCAUCZJF55wAKCRALxc3C7H1l CDIpAP4kmGFSuyp69uWui9laihxxH35pNGIkCvnQs1MAIZYvAgD+MVPI7cZ+4WKi ctaineUcuYKMsPqBCC8411pUQElQiQE= =oN5T -----END PGP SIGNATURE----- --Q/yN9VCYAD/fgz9L--