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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 8FA00C43461 for ; Fri, 16 Apr 2021 22:18:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 63537613CD for ; Fri, 16 Apr 2021 22:18:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235122AbhDPWS6 (ORCPT ); Fri, 16 Apr 2021 18:18:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34954 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230056AbhDPWS4 (ORCPT ); Fri, 16 Apr 2021 18:18:56 -0400 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C061C061574; Fri, 16 Apr 2021 15:18:31 -0700 (PDT) Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 7B55C51E; Sat, 17 Apr 2021 00:18:27 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1618611507; bh=IuCnAAJS5v6qKyuXjBEuQoVksOGIAcJ5BWO3jyoj2DA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=iP5IfDiRuTia/H1IW666sZLLlxVIs388+xasJ/C7VoWAN6txU3k2gyxSflbo6ZSRz C2JPY3mYmNXTievNnInM0detPIu1xst2hkHoqGZHCLOu+xNHJ+NdC4TfT1ckvixql5 bY7GJmpB1gQMb6YTNjoVp8jQtrLCZ+7kaZG5JuPE= Date: Sat, 17 Apr 2021 01:18:25 +0300 From: Laurent Pinchart To: Jacopo Mondi Cc: Jacopo Mondi , Geert Uytterhoeven , Magnus Damm , Kieran Bingham , Rob Herring , linux-renesas-soc@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 2/5] media: i2c: max9286: Use "maxim,gpio-poc" property Message-ID: References: <20210414135128.180980-1-jacopo+renesas@jmondi.org> <20210414135128.180980-3-jacopo+renesas@jmondi.org> <20210415065848.xgisi5cpcxvnxzb4@uno.localdomain> <20210416074307.mtd7bcv3yj6zekt6@uno.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20210416074307.mtd7bcv3yj6zekt6@uno.localdomain> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jacopo, On Fri, Apr 16, 2021 at 09:43:07AM +0200, Jacopo Mondi wrote: > On Thu, Apr 15, 2021 at 10:14:05PM +0300, Laurent Pinchart wrote: > > > > > + /* GPIO values default to high */ > > > > > + priv->gpio_state = BIT(0) | BIT(1); > > > > > > > > Why is that ? > > > > > > > As the set/get functions of gpiochip use the gpio_state and I wanted > > > to use the same functions for the internal gpio handling I used > > > gpio_state in gpio_set(). My thinking was that in this way altering > > > the gpio line would be visibile to gpio consumers... which we don't > > > have as I won't register the gpio-controller :) > > > > My question was why they default to high here, when they default to low > > when there's a gpio-controller property. > > Oh, got it now... the two output lines are high by default :) > Why do you say "they default to low when there's a gpio-controller > property" ? When does that requirement come from ? My bad, I thought they were set to 0 in that case, but they're not. How about moving this initialization from max9286_register_gpio() to the beginning of this function, as it's shared by both cases ? > > > > > + priv->regulator = NULL; > > > > > > > > As priv is initialized to 0, you can skip this. > > > > > > Yes, I liked it explicit as it is used as flag, but it is not > > > required... > > > > > > > > + > > > > > + return 0; > > > > > + } > > > > > + > > > > > + ret = max9286_register_gpio(priv); > > > > > + if (ret) > > > > > + return ret; > > > > > + > > > > > + priv->regulator = devm_regulator_get(dev, "poc"); > > > > > + if (IS_ERR(priv->regulator)) { > > > > > + if (PTR_ERR(priv->regulator) != -EPROBE_DEFER) > > > > > + dev_err(dev, "Unable to get PoC regulator (%ld)\n", > > > > > + PTR_ERR(priv->regulator)); > > > > > + return PTR_ERR(priv->regulator); > > > > > + } > > > > > + > > > > > + return 0; > > > > > +} > > > > > + > > > > > +static int max9286_poc_enable(struct max9286_priv *priv, bool enable) > > > > > +{ > > > > > + int ret; > > > > > + > > > > > + /* If "poc-gpio" is used, toggle the line and do not use regulator. */ > > > > > + if (!priv->regulator) > > > > > + return max9286_gpio_set(priv, priv->gpio_poc, > > > > > + enable ^ priv->gpio_poc_flags); > > > > > + > > > > > + /* Otherwise PoC is controlled using a regulator. */ > > > > > + if (enable) { > > > > > + ret = regulator_enable(priv->regulator); > > > > > + if (ret < 0) { > > > > > + dev_err(&priv->client->dev, "Unable to turn PoC on\n"); > > > > > > > > As error message when max9286_gpio_set() fails (at least in the enable > > > > case) would be good too. Bonus points if there's a single dev_err() > > > > call. > > > > > > I'll see how it looks like > > > > > > > > + return ret; > > > > > + } > > > > > + > > > > > + return 0; > > > > > + } > > > > > + > > > > > + return regulator_disable(priv->regulator); > > > > > +} > > > > > + > > > > > static int max9286_init(struct device *dev) > > > > > { > > > > > struct max9286_priv *priv; > > > > > @@ -1078,17 +1158,14 @@ static int max9286_init(struct device *dev) > > > > > client = to_i2c_client(dev); > > > > > priv = i2c_get_clientdata(client); > > > > > > > > > > - /* Enable the bus power. */ > > > > > - ret = regulator_enable(priv->regulator); > > > > > - if (ret < 0) { > > > > > - dev_err(&client->dev, "Unable to turn PoC on\n"); > > > > > + ret = max9286_poc_enable(priv, true); > > > > > + if (ret) > > > > > return ret; > > > > > - } > > > > > > > > > > ret = max9286_setup(priv); > > > > > if (ret) { > > > > > dev_err(dev, "Unable to setup max9286\n"); > > > > > - goto err_regulator; > > > > > + goto err_poc_disable; > > > > > } > > > > > > > > > > /* > > > > > @@ -1098,7 +1175,7 @@ static int max9286_init(struct device *dev) > > > > > ret = max9286_v4l2_register(priv); > > > > > if (ret) { > > > > > dev_err(dev, "Failed to register with V4L2\n"); > > > > > - goto err_regulator; > > > > > + goto err_poc_disable; > > > > > } > > > > > > > > > > ret = max9286_i2c_mux_init(priv); > > > > > @@ -1114,8 +1191,8 @@ static int max9286_init(struct device *dev) > > > > > > > > > > err_v4l2_register: > > > > > max9286_v4l2_unregister(priv); > > > > > -err_regulator: > > > > > - regulator_disable(priv->regulator); > > > > > +err_poc_disable: > > > > > + max9286_poc_enable(priv, false); > > > > > > > > > > return ret; > > > > > } > > > > > @@ -1286,20 +1363,10 @@ static int max9286_probe(struct i2c_client *client) > > > > > */ > > > > > max9286_configure_i2c(priv, false); > > > > > > > > > > - ret = max9286_register_gpio(priv); > > > > > + ret = max9286_parse_gpios(priv); > > > > > if (ret) > > > > > goto err_powerdown; > > > > > > > > > > - priv->regulator = devm_regulator_get(&client->dev, "poc"); > > > > > - if (IS_ERR(priv->regulator)) { > > > > > - if (PTR_ERR(priv->regulator) != -EPROBE_DEFER) > > > > > - dev_err(&client->dev, > > > > > - "Unable to get PoC regulator (%ld)\n", > > > > > - PTR_ERR(priv->regulator)); > > > > > - ret = PTR_ERR(priv->regulator); > > > > > - goto err_powerdown; > > > > > - } > > > > > - > > > > > ret = max9286_parse_dt(priv); > > > > > if (ret) > > > > > goto err_powerdown; > > > > > @@ -1326,7 +1393,7 @@ static int max9286_remove(struct i2c_client *client) > > > > > > > > > > max9286_v4l2_unregister(priv); > > > > > > > > > > - regulator_disable(priv->regulator); > > > > > + max9286_poc_enable(priv, false); > > > > > > > > > > gpiod_set_value_cansleep(priv->gpiod_pwdn, 0); > > > > > -- Regards, Laurent Pinchart