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 5B511C3524C for ; Sun, 2 Feb 2020 17:25:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2F3FA2080D for ; Sun, 2 Feb 2020 17:25:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580664312; bh=QFx6XAEnnx3HFShS5F8gddxgaI14tq5oojl9WOovMTQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=sNpl5mnYst7vSCLy87ToxcqRLPn4qGFC9bxjcA+1Rjd/mgpioLprFYnc3LwjJ9iS4 /am2EILCnX2NrMmgrD511yfUqAamNC9ekMjkz91B6JizdKEXFfEA4iv/Vyz3nzkQIA 4IBgYLIKrKhPQcUxVnGGSTXbxHjOXY05ozhGY0L0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726943AbgBBRZL (ORCPT ); Sun, 2 Feb 2020 12:25:11 -0500 Received: from mail.kernel.org ([198.145.29.99]:56030 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726525AbgBBRZL (ORCPT ); Sun, 2 Feb 2020 12:25:11 -0500 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 3CB5020658; Sun, 2 Feb 2020 17:25:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580664309; bh=QFx6XAEnnx3HFShS5F8gddxgaI14tq5oojl9WOovMTQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=ssxlXcIguXyhwJ0EB9pYHRVRNABhxs+ndgIUISyrLOEsWRn7tjtsLJ0qvwMUqrgFh tm1EQzoe6e0tZDLJJ1Ob6ZHmcA8iLqjmX1/eXVuY5K/+W2Xt8qpGODgPnw68tWu+ld RzxvTkxUxM8TpFGNvyxGzY+0Hcfeqd0yexpOXt5o= Date: Sun, 2 Feb 2020 17:25:05 +0000 From: Jonathan Cameron To: Andreas Klinger Cc: robh+dt@kernel.org, mark.rutland@arm.com, knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, rpi-receiver@htl-steyr.ac.at, linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 2/2] iio: srf04: add power management feature Message-ID: <20200202172505.4af0f6ef@archlinux> In-Reply-To: <20200120164540.GA8725@arbad> References: <20200120164540.GA8725@arbad> X-Mailer: Claws Mail 3.17.4 (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: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Mon, 20 Jan 2020 17:45:41 +0100 Andreas Klinger wrote: > Add suspend and resume operations for being used by optional power > management. > > The suspend function is switching off an GPIO which can be used by the > hardware to switch power off. The resume function is switching the GPIO > on and sleeps an adjustable time to give the device a chance to be up > and running. > > If activated the driver gets into autosuspend after some time of > inactivity. > > Suggested-by: Franz Parzer > Signed-off-by: Andreas Klinger Applied to the togreg branch of iio.git and pushed out as testing for the autobuilders to poke at it. Thanks, Jonathan > --- > drivers/iio/proximity/srf04.c | 96 ++++++++++++++++++++++++++++++++++- > 1 file changed, 95 insertions(+), 1 deletion(-) > > diff --git a/drivers/iio/proximity/srf04.c b/drivers/iio/proximity/srf04.c > index 01eb8cc63076..568b76e06385 100644 > --- a/drivers/iio/proximity/srf04.c > +++ b/drivers/iio/proximity/srf04.c > @@ -45,6 +45,7 @@ > #include > #include > #include > +#include > #include > #include > > @@ -56,6 +57,7 @@ struct srf04_data { > struct device *dev; > struct gpio_desc *gpiod_trig; > struct gpio_desc *gpiod_echo; > + struct gpio_desc *gpiod_power; > struct mutex lock; > int irqnr; > ktime_t ts_rising; > @@ -63,6 +65,7 @@ struct srf04_data { > struct completion rising; > struct completion falling; > const struct srf04_cfg *cfg; > + int startup_time_ms; > }; > > static const struct srf04_cfg srf04_cfg = { > @@ -97,6 +100,9 @@ static int srf04_read(struct srf04_data *data) > u64 dt_ns; > u32 time_ns, distance_mm; > > + if (data->gpiod_power) > + pm_runtime_get_sync(data->dev); > + > /* > * just one read-echo-cycle can take place at a time > * ==> lock against concurrent reading calls > @@ -110,6 +116,11 @@ static int srf04_read(struct srf04_data *data) > udelay(data->cfg->trigger_pulse_us); > gpiod_set_value(data->gpiod_trig, 0); > > + if (data->gpiod_power) { > + pm_runtime_mark_last_busy(data->dev); > + pm_runtime_put_autosuspend(data->dev); > + } > + > /* it should not take more than 20 ms until echo is rising */ > ret = wait_for_completion_killable_timeout(&data->rising, HZ/50); > if (ret < 0) { > @@ -268,6 +279,22 @@ static int srf04_probe(struct platform_device *pdev) > return PTR_ERR(data->gpiod_echo); > } > > + data->gpiod_power = devm_gpiod_get_optional(dev, "power", > + GPIOD_OUT_LOW); > + if (IS_ERR(data->gpiod_power)) { > + dev_err(dev, "failed to get power-gpios: err=%ld\n", > + PTR_ERR(data->gpiod_power)); > + return PTR_ERR(data->gpiod_power); > + } > + if (data->gpiod_power) { > + > + if (of_property_read_u32(dev->of_node, "startup-time-ms", > + &data->startup_time_ms)) > + data->startup_time_ms = 100; > + dev_dbg(dev, "using power gpio: startup-time-ms=%d\n", > + data->startup_time_ms); > + } > + > if (gpiod_cansleep(data->gpiod_echo)) { > dev_err(data->dev, "cansleep-GPIOs not supported\n"); > return -ENODEV; > @@ -296,14 +323,81 @@ static int srf04_probe(struct platform_device *pdev) > indio_dev->channels = srf04_chan_spec; > indio_dev->num_channels = ARRAY_SIZE(srf04_chan_spec); > > - return devm_iio_device_register(dev, indio_dev); > + ret = iio_device_register(indio_dev); > + if (ret < 0) { > + dev_err(data->dev, "iio_device_register: %d\n", ret); > + return ret; > + } > + > + if (data->gpiod_power) { > + pm_runtime_set_autosuspend_delay(data->dev, 1000); > + pm_runtime_use_autosuspend(data->dev); > + > + ret = pm_runtime_set_active(data->dev); > + if (ret) { > + dev_err(data->dev, "pm_runtime_set_active: %d\n", ret); > + iio_device_unregister(indio_dev); > + } > + > + pm_runtime_enable(data->dev); > + pm_runtime_idle(data->dev); > + } > + > + return ret; > } > > +static int srf04_remove(struct platform_device *pdev) > +{ > + struct iio_dev *indio_dev = platform_get_drvdata(pdev); > + struct srf04_data *data = iio_priv(indio_dev); > + > + iio_device_unregister(indio_dev); > + > + if (data->gpiod_power) { > + pm_runtime_disable(data->dev); > + pm_runtime_set_suspended(data->dev); > + } > + > + return 0; > +} > + > +static int __maybe_unused srf04_pm_runtime_suspend(struct device *dev) > +{ > + struct platform_device *pdev = container_of(dev, > + struct platform_device, dev); > + struct iio_dev *indio_dev = platform_get_drvdata(pdev); > + struct srf04_data *data = iio_priv(indio_dev); > + > + gpiod_set_value(data->gpiod_power, 0); > + > + return 0; > +} > + > +static int __maybe_unused srf04_pm_runtime_resume(struct device *dev) > +{ > + struct platform_device *pdev = container_of(dev, > + struct platform_device, dev); > + struct iio_dev *indio_dev = platform_get_drvdata(pdev); > + struct srf04_data *data = iio_priv(indio_dev); > + > + gpiod_set_value(data->gpiod_power, 1); > + msleep(data->startup_time_ms); > + > + return 0; > +} > + > +static const struct dev_pm_ops srf04_pm_ops = { > + SET_RUNTIME_PM_OPS(srf04_pm_runtime_suspend, > + srf04_pm_runtime_resume, NULL) > +}; > + > static struct platform_driver srf04_driver = { > .probe = srf04_probe, > + .remove = srf04_remove, > .driver = { > .name = "srf04-gpio", > .of_match_table = of_srf04_match, > + .pm = &srf04_pm_ops, > }, > }; >