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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 92DB0C25B6E for ; Fri, 27 Oct 2023 06:09:17 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qwG1l-00056d-VE; Fri, 27 Oct 2023 02:09:01 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qwG1j-00055j-CX; Fri, 27 Oct 2023 02:08:59 -0400 Received: from pi.codeconstruct.com.au ([203.29.241.158] helo=codeconstruct.com.au) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qwG1g-0001Ni-Ik; Fri, 27 Oct 2023 02:08:59 -0400 Received: from [192.168.68.112] (ppp118-210-136-142.adl-adc-lon-bras33.tpg.internode.on.net [118.210.136.142]) by mail.codeconstruct.com.au (Postfix) with ESMTPSA id F052A2017B; Fri, 27 Oct 2023 14:08:48 +0800 (AWST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=codeconstruct.com.au; s=2022a; t=1698386929; bh=g16CvfS0OYfewcGbYBDyxJR0tshXGS+QzvGp+YH9ZjE=; h=Subject:From:To:Cc:Date:In-Reply-To:References; b=i3Ts+pL/d1TFjlNz9Y1HYhlDBJvHKIcd6HfOTEOBKuFc60r3Y9iolHzXMx9cB/h34 QUDf8LQc2zxOhheECJ5Z1vx6K8XxWBdz0o8MqgYj2r/nGNgCG5QRD0H35+YXCAsXaE GRT5lt/1xErBFN/faOLwET9AsY0d8m770/dEEti6Cz7/qlTKdrXYmOrGMgQgW3zXVj 29/J/UpyrA6/wJaoDyaUpWlH8e481xMUwL7W8ssZxoyw0Q1CSPaD19WAWDtEezhNlt k0jhbhAnX9Zx6edBWMslfWqNuTH/owgz0yJdtNmFWNZInKPyb92baX+w8ZXzFMbcoW IYDVihORiM7JA== Message-ID: Subject: Re: [PATCH v3 2/2] misc/pca9552: Let external devices set pca9552 inputs From: Andrew Jeffery To: Glenn Miles , qemu-devel@nongnu.org Cc: qemu-arm@nongnu.org, clg@kaod.org, joel@jms.id.au, philmd@linaro.org Date: Fri, 27 Oct 2023 16:38:48 +1030 In-Reply-To: <20231024181144.4045056-3-milesg@linux.vnet.ibm.com> References: <20231024181144.4045056-1-milesg@linux.vnet.ibm.com> <20231024181144.4045056-3-milesg@linux.vnet.ibm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.46.4-2 MIME-Version: 1.0 Received-SPF: pass client-ip=203.29.241.158; envelope-from=andrew@codeconstruct.com.au; helo=codeconstruct.com.au X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Tue, 2023-10-24 at 13:11 -0500, Glenn Miles wrote: > Allow external devices to drive pca9552 input pins by adding > input GPIO's to the model. This allows a device to connect > its output GPIO's to the pca9552 input GPIO's. >=20 > In order for an external device to set the state of a pca9552 > pin, the pin must first be configured for high impedance (LED > is off). If the pca9552 pin is configured to drive the pin low > (LED is on), then external input will be ignored. >=20 > Here is a table describing the logical state of a pca9552 pin > given the state being driven by the pca9552 and an external device: >=20 > PCA9552 > Configured > State >=20 > | Hi-Z | Low | > ------+------+-----+ > External Hi-Z | Hi | Low | > Device ------+------+-----+ > State Low | Low | Low | > ------+------+-----+ >=20 > Signed-off-by: Glenn Miles Reviewed-by: Andrew Jeffery