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 9061DC433FE for ; Sat, 26 Feb 2022 20:54:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229676AbiBZUzA (ORCPT ); Sat, 26 Feb 2022 15:55:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35842 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229642AbiBZUy7 (ORCPT ); Sat, 26 Feb 2022 15:54:59 -0500 Received: from ssl.serverraum.org (ssl.serverraum.org [IPv6:2a01:4f8:151:8464::1:2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6F5E223D034; Sat, 26 Feb 2022 12:54:24 -0800 (PST) Received: from ssl.serverraum.org (web.serverraum.org [172.16.0.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id BE5422223E; Sat, 26 Feb 2022 21:54:22 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1645908862; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=baGxETKr4EyF+PTNs4Sn3z1hVCPQByp//FE2CcA1b7g=; b=D4VnMIECv6YoV/ao41odEWY547ULVDOeHgLD5tsPU9P/o/f9SDgfO0/vEHXMuzSUU33nWN qVO+jqmpjIgPC/OcuPmQAKnVp8BjkcqNgOjjGttO+/Ce7HgMUnU1Hc/xQSpx0BdT/9eNmt SXY2v2yzQS1/Ba0wKxp+UP4TtA/3QCI= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Sat, 26 Feb 2022 21:54:22 +0100 From: Michael Walle To: Colin Foster Cc: Horatiu Vultur , Lars Povlsen , Steen Hegelund , Linus Walleij , UNGLinuxDriver@microchip.com, linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1 5/5] pinctrl: microchip-sgpio: wait until output is actually set In-Reply-To: <20220225165446.GA4704@COLIN-DESKTOP1.localdomain> References: <20220224161021.2197263-1-michael@walle.cc> <20220224161021.2197263-6-michael@walle.cc> <20220225092427.jjilv3qo52crsmuw@soft-dev3-1.localhost> <2f8a215c67269d639290515931d10b78@walle.cc> <20220225165446.GA4704@COLIN-DESKTOP1.localdomain> User-Agent: Roundcube Webmail/1.4.12 Message-ID: <5ab71056170ea00dc0d2ed8f7b9802db@walle.cc> X-Sender: michael@walle.cc Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Colin, Am 2022-02-25 17:54, schrieb Colin Foster: > On Fri, Feb 25, 2022 at 12:29:50PM +0100, Michael Walle wrote: >> >> Could you also have a look at the other supported sgpio block, >> the ocelot and the luton? I don't have any register description >> of these. > > The current supported Ocelot chips are the VSC7514 (link below) and the > VSC7513. Chapter 6 of this PDF links a second PDF, and you should be > able to find the Serial GPIO definitions in DEVCPU_GCB:SIO_CTRL on page > 79 of that PDF. > https://ww1.microchip.com/downloads/en/DeviceDoc/VMDS-10491.pdf Thanks! I've just send a new version with support for these. > I'm working on support for the VSC7511/7512, so I can run a "does it > work" test, but I likely won't have a setup to test the corner > conditions this patch set is addressing with any confidence. You can time the register polling using ktime_get(), ktime_sub() and ktime_to_ns(). It should be in the magnitude of the burst gap. Which will give you at least some confidence. I did the testing with an oscilloscope and toggling gpios (but also did measure the timing with ktime_get()). -michael