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 X-Spam-Level: X-Spam-Status: No, score=-13.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BFB74C4361A for ; Sat, 5 Dec 2020 18:55:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 71A0B2310E for ; Sat, 5 Dec 2020 18:55:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726136AbgLESza (ORCPT ); Sat, 5 Dec 2020 13:55:30 -0500 Received: from mail-ot1-f66.google.com ([209.85.210.66]:40224 "EHLO mail-ot1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726126AbgLESz3 (ORCPT ); Sat, 5 Dec 2020 13:55:29 -0500 Received: by mail-ot1-f66.google.com with SMTP id j12so8624781ota.7; Sat, 05 Dec 2020 10:55:08 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=5313XC3NfbvTufqGnoEAJCgFERCH+JaQxzJ9SkuUnEI=; b=GPgQcewdYOUcJbmjrgAPum8YziaQz1zD1qSAcoE8BqjHmRt9zEL2hFjNXWQPKoTJiP rq0p+S/5mEqQp1t7GQqBCM4ZN5NgTwlQaRy+f1Bp3NQUQ7ux1SwmCJHISCJ7fzo64zbx GIP6xR5rApk9d+k1StsoA8jw9MtAwetIYEPXlaB0SMJWGHcVy6SeqSxN1H8sTd9mGFFn 0Xh0h9IqTC9Yk3SZWcVDmJfKHCn4EDK6Ze/nolgDuC2U4z/WM237AtsMxFDrFlW70VwB Ya9bvXLE2W6Ucah8es3oknVM3htGONItVNKNjeoKR90esUxulymjgkWKCMo1FjohzLip SQQQ== X-Gm-Message-State: AOAM531bqJeHHvrzt8OEte7cyXPMTmpZYY2YBSRBWkrOv94HE8Izv3Nf HDi744kO8bGvn8xI0ngKjNV6IKv2He2mtSM9lwE= X-Google-Smtp-Source: ABdhPJyHhcwE29b9kUY2JgtRiLm4Fpspo3qTwPzC7XurwuY7tdRsTokCyB+6/3Eipnvz05ZHTOnotkt0sxEnVBUvuP0= X-Received: by 2002:a9d:2203:: with SMTP id o3mr7913179ota.107.1607194483442; Sat, 05 Dec 2020 10:54:43 -0800 (PST) MIME-Version: 1.0 References: <20201205183355.6488-1-michael.srba@seznam.cz> In-Reply-To: <20201205183355.6488-1-michael.srba@seznam.cz> From: Geert Uytterhoeven Date: Sat, 5 Dec 2020 19:54:32 +0100 Message-ID: Subject: Re: [PATCH 1/3] media: i2c: imx219: add support for specifying clock-frequencies To: michael.srba@seznam.cz Cc: Dave Stevenson , Mauro Carvalho Chehab , Rob Herring , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , Geert Uytterhoeven , Magnus Damm , Linux Media Mailing List , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Linux ARM , Linux-Renesas Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Michael, On Sat, Dec 5, 2020 at 7:36 PM wrote: > From: Michael Srba > > This patch adds 1% tolerance on input clock, similar to other camera sensor > drivers. It also allows for specifying the actual clock in the device tree, > instead of relying on it being already set to the right frequency (which is > often not the case). > > Signed-off-by: Michael Srba Thanks for your patch! > --- a/drivers/media/i2c/imx219.c > +++ b/drivers/media/i2c/imx219.c > @@ -1443,13 +1443,26 @@ static int imx219_probe(struct i2c_client *client) > return PTR_ERR(imx219->xclk); > } > > - imx219->xclk_freq = clk_get_rate(imx219->xclk); > - if (imx219->xclk_freq != IMX219_XCLK_FREQ) { > + ret = fwnode_property_read_u32(dev_fwnode(dev), "clock-frequency", &imx219->xclk_freq); > + if (ret) { > + dev_err(dev, "could not get xclk frequency\n"); > + return ret; This breaks compatibility with existing DTBs, which do not have the clock-frequency property. For backwards compatibility, you should assume the default 24 MHz instead of returning an error. > + } > + > + /* this driver currently expects 24MHz; allow 1% tolerance */ > + if (imx219->xclk_freq < 23760000 || imx219->xclk_freq > 24240000) { > dev_err(dev, "xclk frequency not supported: %d Hz\n", > imx219->xclk_freq); > return -EINVAL; > } > > + ret = clk_set_rate(imx219->xclk, imx219->xclk_freq); > + if (ret) { > + dev_err(dev, "could not set xclk frequency\n"); > + return ret; > + } > + > + > ret = imx219_get_regulators(imx219); > if (ret) { > dev_err(dev, "failed to get regulators\n"); Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds 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 X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C97A4C4361A for ; Sat, 5 Dec 2020 18:56:15 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 470522310B for ; Sat, 5 Dec 2020 18:56:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 470522310B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:To:Subject:Message-ID:Date:From:In-Reply-To: References:MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=k1jTFLWxVr+gHY3976tDlf7XGJmkCYQDPqCtwtvtWpE=; b=eaSzoXXIsWqD22llOj0jeqtH3 lDlWvL7f1qqa/L9nrjzPQXSlsRX+QEkj6j+v+Mvu9v4A0OWbK290PA9nZUBnATKhAiNf3edWpH8s4 lxWdyh5VMxxeVwjnN59acfslshF81MXCxaKIQVBaf5HecQn05sX3nmxkasLSLIgGP3KAkNu/KEjHK T2ZaneIsQFkWdIbxsFc6Ta3NgX6PVD7yFvvPi6G/BRPMFIIOBqYs4tPAlGbEddcCYSZhoEq28n7I7 zAooL/pC5/c1y5UHbAsmSbslYXlS7ILP6LtG1N/wOW3YEafie3bbLUFx1VnQZNa4DhJrH4+DI8NaM T1MFjNX8w==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1klchl-0002bY-Sa; Sat, 05 Dec 2020 18:54:50 +0000 Received: from mail-ot1-f67.google.com ([209.85.210.67]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1klchh-0002bD-T2 for linux-arm-kernel@lists.infradead.org; Sat, 05 Dec 2020 18:54:47 +0000 Received: by mail-ot1-f67.google.com with SMTP id 11so8631004oty.9 for ; Sat, 05 Dec 2020 10:54:43 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=5313XC3NfbvTufqGnoEAJCgFERCH+JaQxzJ9SkuUnEI=; b=UzVaz749liKEMGyvExP3AAFjOHtesEpaZZ108jkJEjh8TBiY/lXIb+Y5ulRu3ZVU/g aZ5IpmvC/b+NNRYEMh35ezhVyr+5pyqwWuA9iERU7Kc0SvLjJMQcMXAUNDUe040Ai1l6 m4E7ha0HWsprF29cgEkAI7KWyBsCxuIm17jxQc7pt4uRKBn1OdJ3Y0rVwDrduku7xqp/ fJKeYS76XSq7hlxqhAF7BJYnxzI9ou9y/mbOYQ+ZVsro6aGSaFg5mMfe8GJLWLLUDDBN g60TuvF3t4wOz2+5RIt3NDTcqhq7IImWTzKNYA05lhBAPQvo44WT5NOfZ9Usts8YvQnS RkHQ== X-Gm-Message-State: AOAM531o/IPHwpZfm9g7s6bVc0peYdHzK51VOvpve4bCJunzC/qgtT7F +VjCE2HElPaMgxSrW9VhrSrnPj71Mu/A74xue0M= X-Google-Smtp-Source: ABdhPJyHhcwE29b9kUY2JgtRiLm4Fpspo3qTwPzC7XurwuY7tdRsTokCyB+6/3Eipnvz05ZHTOnotkt0sxEnVBUvuP0= X-Received: by 2002:a9d:2203:: with SMTP id o3mr7913179ota.107.1607194483442; Sat, 05 Dec 2020 10:54:43 -0800 (PST) MIME-Version: 1.0 References: <20201205183355.6488-1-michael.srba@seznam.cz> In-Reply-To: <20201205183355.6488-1-michael.srba@seznam.cz> From: Geert Uytterhoeven Date: Sat, 5 Dec 2020 19:54:32 +0100 Message-ID: Subject: Re: [PATCH 1/3] media: i2c: imx219: add support for specifying clock-frequencies To: michael.srba@seznam.cz X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201205_135445_957519_3AA14202 X-CRM114-Status: GOOD ( 20.85 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Geert Uytterhoeven , Dave Stevenson , Fabio Estevam , Sascha Hauer , Magnus Damm , Linux-Renesas , Rob Herring , NXP Linux Team , Pengutronix Kernel Team , Mauro Carvalho Chehab , Shawn Guo , Linux ARM , Linux Media Mailing List Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Michael, On Sat, Dec 5, 2020 at 7:36 PM wrote: > From: Michael Srba > > This patch adds 1% tolerance on input clock, similar to other camera sensor > drivers. It also allows for specifying the actual clock in the device tree, > instead of relying on it being already set to the right frequency (which is > often not the case). > > Signed-off-by: Michael Srba Thanks for your patch! > --- a/drivers/media/i2c/imx219.c > +++ b/drivers/media/i2c/imx219.c > @@ -1443,13 +1443,26 @@ static int imx219_probe(struct i2c_client *client) > return PTR_ERR(imx219->xclk); > } > > - imx219->xclk_freq = clk_get_rate(imx219->xclk); > - if (imx219->xclk_freq != IMX219_XCLK_FREQ) { > + ret = fwnode_property_read_u32(dev_fwnode(dev), "clock-frequency", &imx219->xclk_freq); > + if (ret) { > + dev_err(dev, "could not get xclk frequency\n"); > + return ret; This breaks compatibility with existing DTBs, which do not have the clock-frequency property. For backwards compatibility, you should assume the default 24 MHz instead of returning an error. > + } > + > + /* this driver currently expects 24MHz; allow 1% tolerance */ > + if (imx219->xclk_freq < 23760000 || imx219->xclk_freq > 24240000) { > dev_err(dev, "xclk frequency not supported: %d Hz\n", > imx219->xclk_freq); > return -EINVAL; > } > > + ret = clk_set_rate(imx219->xclk, imx219->xclk_freq); > + if (ret) { > + dev_err(dev, "could not set xclk frequency\n"); > + return ret; > + } > + > + > ret = imx219_get_regulators(imx219); > if (ret) { > dev_err(dev, "failed to get regulators\n"); Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel