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 0FC6EC4167B for ; Sun, 10 Dec 2023 12:22:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232170AbjLJMWV (ORCPT ); Sun, 10 Dec 2023 07:22:21 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49464 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229482AbjLJMWU (ORCPT ); Sun, 10 Dec 2023 07:22:20 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D444EFF for ; Sun, 10 Dec 2023 04:22:26 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9DDD5C433C8; Sun, 10 Dec 2023 12:22:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1702210946; bh=soHpppCx2/0tcuziKrSgy12+x/XFsaso6RhP5ZsXMGE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=g7pb7o+TXb3k5qiipbQOoYvEPmYh4Nv7Y+N2wxjgjdXT8U+JIMUgKiLODex7rl9jv tNS2bupApGOy/Y6W1fi4d4RbletRkIp4bGLAaXr/djNWY+h64bGXB6411qYxwTI1Qn 3VbjNjhTOgSjlEUJCdgK3K4lrlpa06s86pXXqIPeTonDijFqFFpIFUuK8olNHkggtP /5vLkrwPSxGtghhmYS8MNWWKPVgE4nG9/SCXD+ouwzeDS0B8KHZEnIwEfAKCrRFf7F vOU+jISiSDBoZvl3iETiFvOtsbXbdWmRQjHEjSHnNboEN0qtVNi9IMGHZbyfBGFaJf +Eiz2HedbvWdQ== Date: Sun, 10 Dec 2023 12:22:18 +0000 From: Jonathan Cameron To: Marcelo Schmitt Cc: , , , , , , , , , , , , , , Subject: Re: [PATCH v3 08/13] iio: adc: ad7091r: Enable internal vref if external vref is not supplied Message-ID: <20231210122218.6c0c1d19@jic23-huawei> In-Reply-To: <0c71001f4c1eba169230caee6640661cec4b979b.1701971344.git.marcelo.schmitt1@gmail.com> References: <0c71001f4c1eba169230caee6640661cec4b979b.1701971344.git.marcelo.schmitt1@gmail.com> X-Mailer: Claws Mail 4.2.0 (GTK 3.24.38; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 7 Dec 2023 15:41:25 -0300 Marcelo Schmitt wrote: > The ADC needs a voltage reference to work correctly. > Enable AD7091R internal voltage reference if no external vref is > supplied. > > Signed-off-by: Marcelo Schmitt > --- > drivers/iio/adc/ad7091r-base.c | 9 ++++++--- > drivers/iio/adc/ad7091r-base.h | 1 + > 2 files changed, 7 insertions(+), 3 deletions(-) > > diff --git a/drivers/iio/adc/ad7091r-base.c b/drivers/iio/adc/ad7091r-base.c > index f2cb638b8d77..59a7ec44955d 100644 > --- a/drivers/iio/adc/ad7091r-base.c > +++ b/drivers/iio/adc/ad7091r-base.c > @@ -215,10 +215,13 @@ int ad7091r_probe(struct device *dev, const char *name, > iio_dev->channels = st->chip_info->channels; > > st->vref = devm_regulator_get_optional(dev, "vref"); This does not return NULL, only a valid regulator or an error code. > - if (IS_ERR(st->vref)) { > - if (PTR_ERR(st->vref) == -EPROBE_DEFER) > - return -EPROBE_DEFER; > + if (IS_ERR_OR_NULL(st->vref)) { You still need to explicitly handle deferal here. There might be a perfectly good regulator that just isn't ready yet and if that happens we want to try probing this driver again later rather than papering over it. > + /* Enable internal vref */ > st->vref = NULL; > + ret = regmap_update_bits(st->map, AD7091R_REG_CONF, > + AD7091R_REG_CONF_INT_VREF, BIT(0)); > + if (ret) > + return ret; > } else { > ret = regulator_enable(st->vref); > if (ret) > diff --git a/drivers/iio/adc/ad7091r-base.h b/drivers/iio/adc/ad7091r-base.h > index 9546d0bf1da7..e153c2d7deb5 100644 > --- a/drivers/iio/adc/ad7091r-base.h > +++ b/drivers/iio/adc/ad7091r-base.h > @@ -20,6 +20,7 @@ > #define AD7091R_REG_CH_HYSTERESIS(ch) ((ch) * 3 + 6) > > /* AD7091R_REG_CONF */ > +#define AD7091R_REG_CONF_INT_VREF BIT(0) > #define AD7091R_REG_CONF_ALERT_EN BIT(4) > #define AD7091R_REG_CONF_AUTO BIT(8) > #define AD7091R_REG_CONF_CMD BIT(10)