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=-6.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 DDA89C433DF for ; Tue, 19 May 2020 13:26:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD328204EA for ; Tue, 19 May 2020 13:26:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gerhold.net header.i=@gerhold.net header.b="fwr+dDGE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728854AbgESN0e (ORCPT ); Tue, 19 May 2020 09:26:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46820 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726880AbgESN0e (ORCPT ); Tue, 19 May 2020 09:26:34 -0400 Received: from mo6-p02-ob.smtp.rzone.de (mo6-p02-ob.smtp.rzone.de [IPv6:2a01:238:20a:202:5302::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B15F5C08C5C0; Tue, 19 May 2020 06:26:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1589894792; s=strato-dkim-0002; d=gerhold.net; h=In-Reply-To:References:Message-ID:Subject:Cc:To:From:Date: X-RZG-CLASS-ID:X-RZG-AUTH:From:Subject:Sender; bh=/iyQysFjE7xolBZ1naSvo7228GHiugrOaI4sO8bPUTk=; b=fwr+dDGEkpoZpHRFsi8fcLwOsy/sYVESVb8GgLSpv79t4LUto9ST3ru1G2W+/CNwUq jsKGEs64/RRB2TBFLOhxGwgyGUi/0C9R/12t0ttN6ghkc7h7qa4ziOZQH0bTDYb4fIhG zfMC/tbsIUoA8ygDpRE9b0aSD1/Mo1N2L3fKZEfEuJTL1xOZP869A/CZ+/Hulugqnwh6 EIWjwN126W3TG9fRQZHxF1QPQaCMFZaD7X7Wc7+TX444DaIfLjlxyxxCLoAx+H17hnAU u5Yauj09xAg7rlIo7bs97bvRPURUeYWWuh/+E7UPFhw770eXxnIwg1CFGQpUJnkc1yNy sJsQ== X-RZG-AUTH: ":P3gBZUipdd93FF5ZZvYFPugejmSTVR2nRPhVOQ/OcYgojyw4j34+u26zEodhPgRDZ8j9IczFaoo=" X-RZG-CLASS-ID: mo00 Received: from gerhold.net by smtp.strato.de (RZmta 46.6.2 DYNA|AUTH) with ESMTPSA id 60b02dw4JDPDl1o (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256 bits)) (Client did not present a certificate); Tue, 19 May 2020 15:25:13 +0200 (CEST) Date: Tue, 19 May 2020 15:25:12 +0200 From: Stephan Gerhold To: Jonathan Albrieux Cc: linux-kernel@vger.kernel.org, ~postmarketos/upstreaming@lists.sr.ht, Andy Shevchenko , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Greg Kroah-Hartman , Hartmut Knaack , Jilayne Lovejoy , Jonathan Cameron , Kate Stewart , Lars-Peter Clausen , Linus Walleij , "open list:IIO SUBSYSTEM AND DRIVERS" , Peter Meerwald-Stadler , Steve Winslow , Thomas Gleixner , Jonathan Cameron , Allison Randal Subject: Re: [PATCH v3 4/4] iio: magnetometer: ak8975: Add gpio reset support Message-ID: <20200519132512.GC4623@gerhold.net> References: <20200519124402.26076-1-jonathan.albrieux@gmail.com> <20200519124402.26076-5-jonathan.albrieux@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200519124402.26076-5-jonathan.albrieux@gmail.com> Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Tue, May 19, 2020 at 02:43:54PM +0200, Jonathan Albrieux wrote: > According to AK09911 datasheet, if reset gpio is provided then > deassert reset on ak8975_power_on() and assert reset on ak8975_power_off(). > > Without reset's deassertion during ak8975_power_on(), driver's probe fails > on ak8975_who_i_am while() checking for device identity for AK09911 chip. > > AK09911 has an active low reset gpio to handle register's reset. > AK09911 datasheed says that, if not used, reset pin should be connected Another minor typo: datasheed -> datasheet In any case, FWIW: Reviewed-by: Stephan Gerhold > to VID. This patch emulates this situation. > > Signed-off-by: Jonathan Albrieux > --- > drivers/iio/magnetometer/ak8975.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c > index fd368455cd7b..a23422aad97d 100644 > --- a/drivers/iio/magnetometer/ak8975.c > +++ b/drivers/iio/magnetometer/ak8975.c > @@ -358,6 +358,7 @@ struct ak8975_data { > u8 asa[3]; > long raw_to_gauss[3]; > struct gpio_desc *eoc_gpiod; > + struct gpio_desc *reset_gpiod; > int eoc_irq; > wait_queue_head_t data_ready_queue; > unsigned long flags; > @@ -384,6 +385,9 @@ static int ak8975_power_on(const struct ak8975_data *data) > "Failed to enable specified Vid supply\n"); > return ret; > } > + > + gpiod_set_value_cansleep(data->reset_gpiod, 0); > + > /* > * According to the datasheet the power supply rise time is 200us > * and the minimum wait time before mode setting is 100us, in > @@ -396,6 +400,8 @@ static int ak8975_power_on(const struct ak8975_data *data) > /* Disable attached power regulator if any. */ > static void ak8975_power_off(const struct ak8975_data *data) > { > + gpiod_set_value_cansleep(data->reset_gpiod, 1); > + > regulator_disable(data->vid); > regulator_disable(data->vdd); > } > @@ -839,6 +845,7 @@ static int ak8975_probe(struct i2c_client *client, > struct ak8975_data *data; > struct iio_dev *indio_dev; > struct gpio_desc *eoc_gpiod; > + struct gpio_desc *reset_gpiod; > const void *match; > unsigned int i; > int err; > @@ -856,6 +863,16 @@ static int ak8975_probe(struct i2c_client *client, > if (eoc_gpiod) > gpiod_set_consumer_name(eoc_gpiod, "ak_8975"); > > + /* > + * According to AK09911 datasheet, if reset GPIO is provided then > + * deassert reset on ak8975_power_on() and assert reset on > + * ak8975_power_off(). > + */ > + reset_gpiod = devm_gpiod_get_optional(&client->dev, > + "reset", GPIOD_OUT_HIGH); > + if (IS_ERR(reset_gpiod)) > + return PTR_ERR(reset_gpiod); > + > /* Register with IIO */ > indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); > if (indio_dev == NULL) > @@ -866,6 +883,7 @@ static int ak8975_probe(struct i2c_client *client, > > data->client = client; > data->eoc_gpiod = eoc_gpiod; > + data->reset_gpiod = reset_gpiod; > data->eoc_irq = 0; > > err = iio_read_mount_matrix(&client->dev, "mount-matrix", &data->orientation); > -- > 2.17.1