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=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 D5F78C4338F for ; Fri, 20 Aug 2021 08:21:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C0DA961075 for ; Fri, 20 Aug 2021 08:21:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231765AbhHTIWR (ORCPT ); Fri, 20 Aug 2021 04:22:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34444 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231672AbhHTIWR (ORCPT ); Fri, 20 Aug 2021 04:22:17 -0400 Received: from mail-pg1-x534.google.com (mail-pg1-x534.google.com [IPv6:2607:f8b0:4864:20::534]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B3E14C061575 for ; Fri, 20 Aug 2021 01:21:39 -0700 (PDT) Received: by mail-pg1-x534.google.com with SMTP id w8so8414976pgf.5 for ; Fri, 20 Aug 2021 01:21:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=VK/hEmBwSjcbOGKG+JPCR+9UqW8jwiQdNgYDKZJCOA0=; b=GmjdQrW/k8fXOp/RL/hDIvfngbVg2t7hMjQR7Bbvt7A7e1qm2TgQRTsg1Z+46fjvoe kLMTKTDw97XAV9wh2Vpk1hQqswPllOfV6oyuETNrviWxQAVx2Z/skpHVVcD8YKyNpUHV azGIqJ1i7N74oPn77+bidFVkzstEFGGeFtG03Scu1nEnZraHRzhH5aPFeqRxQhEsBPF+ RdNYQA5HJdTjLXLiTzOUwReqwdVDcuBlDig97RsUaXTgE2BFOK6E/gVw2oS9iDGFzDc4 mDMyc6ITcKgAo3elAFTfOxapGDzTlTEVgu4Y7/abc0/FYadpGUE48WBuZnfrjqJiMsWW TO1g== 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:content-transfer-encoding; bh=VK/hEmBwSjcbOGKG+JPCR+9UqW8jwiQdNgYDKZJCOA0=; b=K4M6otpR+lH72zTt2/3WsGpvwOwrGKokebeE7FpaSpWauxvKIVUTTiphUSYS6ncJ8e lM6wGBXIU613A3xp8VI0dpuJvNmy7YCeuHeCjSUBrDEenSXf9o5DPCCBTk9dRajVXfnL XmAhsyHgbkh4YH9tYkBOXO8q3uaDKFQXXoRz4WYMF4nAPIdRyNXy4+5Z8MRK0lYD9odz ovsuqhYG22V0aQTKF4Ojh2IoXPmJZ9wQampd3lOQ/t7w/y+vVuFQ7+zBe2J2pP3YPT/9 ++Vn7gOWjiNkrsp/LTS3GghX/Uu28QxuzeRu3WnHJ3wS+gGsF8N+zCvk8a67IwEzqsOG g1Ig== X-Gm-Message-State: AOAM532aXwzqQ/Qju+yyXLhCVgMY6S2EeSDx2PMVxk3tz/+45vXjlCPg B8m2KDh5UKMYQCYfofttaQMt2W9iVGAteIeOw6Y= X-Google-Smtp-Source: ABdhPJyIRtmDyr7SrbSr3VjPCwNa5prVFA3IJJYogaip5ISM9j78eHR6h/XNlnjwB/REagVVnt93lXffH22bRH+l7Vo= X-Received: by 2002:a05:6a00:2343:b0:3e0:f9a0:c1fa with SMTP id j3-20020a056a00234300b003e0f9a0c1famr18772601pfj.72.1629447699205; Fri, 20 Aug 2021 01:21:39 -0700 (PDT) MIME-Version: 1.0 References: <20210820065535.6994-1-nuno.sa@analog.com> In-Reply-To: <20210820065535.6994-1-nuno.sa@analog.com> From: Alexandru Ardelean Date: Fri, 20 Aug 2021 11:21:27 +0300 Message-ID: Subject: Re: [PATCH 1/2] iio: ltc2983: add support for optional reset gpio To: =?UTF-8?B?TnVubyBTw6E=?= Cc: linux-iio , Jonathan Cameron , Lars-Peter Clausen , Drew Fustini Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Fri, Aug 20, 2021 at 9:53 AM Nuno S=C3=A1 wrote: > > Check if an optional reset gpio is present and if so, make sure to reset > the device. > Just one note/question inline. > Signed-off-by: Nuno S=C3=A1 > --- > drivers/iio/temperature/ltc2983.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/drivers/iio/temperature/ltc2983.c b/drivers/iio/temperature/= ltc2983.c > index 3b4a0e60e605..37903e9fb90f 100644 > --- a/drivers/iio/temperature/ltc2983.c > +++ b/drivers/iio/temperature/ltc2983.c > @@ -1470,6 +1470,7 @@ static int ltc2983_probe(struct spi_device *spi) > { > struct ltc2983_data *st; > struct iio_dev *indio_dev; > + struct gpio_desc *gpio; > const char *name =3D spi_get_device_id(spi)->name; > int ret; > > @@ -1494,6 +1495,16 @@ static int ltc2983_probe(struct spi_device *spi) > if (ret) > return ret; > > + gpio =3D devm_gpiod_get_optional(&st->spi->dev, "reset", GPIOD_OU= T_HIGH); > + if (IS_ERR(gpio)) > + return PTR_ERR(gpio); > + > + if (gpio) { > + /* bring device out of reset */ > + usleep_range(1000, 1005); > + gpiod_set_value_cansleep(gpio, 0); Datasheet mentions that it takes up to 100 ms for the device to fully start= -up. It also mentions that the (command) status register will be unavailable to the user before this point. Page 16, Conversion State Details section, second paragraph. I think there should probably be a sleep here of 100 ms. Other than that change looks good. > + } > + > ret =3D ltc2983_setup(st, true); > if (ret) > return ret; > -- > 2.33.0 >