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=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 D774FC433E1 for ; Sun, 31 May 2020 11:02:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B68CF20671 for ; Sun, 31 May 2020 11:02:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590922966; bh=jXwWsb23m6ezxDQa9hsQPiTnyIvl1U6CQHawMcXP1u0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=nk5grS2/V/wfKmY/Zejm43mrFWeRmjF1imN1btsG4ZCwPQ8624nWbIspiG8+m/ppK To7XMV1bphLProtNuo/iiafC9vocup50Su7d5dQDP1FotWRZZ5bL7276tiVXTB6muI 8BqoqWPwQ+yMOZ4n0hmShRgj9LE3LRMqgJyZU+aU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729694AbgEaLCq (ORCPT ); Sun, 31 May 2020 07:02:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:56746 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728292AbgEaLCe (ORCPT ); Sun, 31 May 2020 07:02:34 -0400 Received: from archlinux (cpc149474-cmbg20-2-0-cust94.5-4.cable.virginm.net [82.4.196.95]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BD98320671; Sun, 31 May 2020 11:02:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590922954; bh=jXwWsb23m6ezxDQa9hsQPiTnyIvl1U6CQHawMcXP1u0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=BLsg5Nn6/nFv3kdwiVrT8dz3ZWJK5tctyCPBlfT9Vqp3zJENdoPAfw0EHrt3aPfJl /Y9MzCS4eabrw8S5t55fg6buKc33tbEsPDT1bGRd9W6Bl2SwE3Gtk9NC6YSAMnv6xO XnmfhU/DCvUjsUmXyb3sw0BYwbbQupaQ28uRlyM4= Date: Sun, 31 May 2020 12:02:30 +0100 From: Jonathan Cameron To: Jonathan Albrieux Cc: linux-kernel@vger.kernel.org, ~postmarketos/upstreaming@lists.sr.ht, Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Andy Shevchenko , Linus Walleij , linux-iio@vger.kernel.org (open list:IIO SUBSYSTEM AND DRIVERS) Subject: Re: [PATCH v7 5/5] iio: magnetometer: ak8975: Add gpio reset support Message-ID: <20200531120230.27093a41@archlinux> In-Reply-To: <20200528150106.12022-1-jonathan.albrieux@gmail.com> References: <20200528150106.12022-1-jonathan.albrieux@gmail.com> X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 28 May 2020 17:01:05 +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 datasheet says that, if not used, reset pin should be connected > to VID. This patch emulates this situation. > > Signed-off-by: Jonathan Albrieux > Reviewed-by: Andy Shevchenko > Reviewed-by: Stephan Gerhold Applied. Thanks, Jonathan > --- > 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);