From patchwork Mon Jan 20 16:45:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andreas Klinger X-Patchwork-Id: 11342587 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3615313A4 for ; Mon, 20 Jan 2020 16:46:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1E47E2073D for ; Mon, 20 Jan 2020 16:46:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726942AbgATQqB (ORCPT ); Mon, 20 Jan 2020 11:46:01 -0500 Received: from mout.kundenserver.de ([217.72.192.74]:50119 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726642AbgATQqB (ORCPT ); Mon, 20 Jan 2020 11:46:01 -0500 Received: from localhost ([217.91.205.33]) by mrelayeu.kundenserver.de (mreue109 [212.227.15.183]) with ESMTPSA (Nemesis) id 1MZTyi-1j6BdY0P4Q-00WUV8; Mon, 20 Jan 2020 17:45:42 +0100 Date: Mon, 20 Jan 2020 17:45:41 +0100 From: Andreas Klinger To: jic23@kernel.org, robh+dt@kernel.org, mark.rutland@arm.com Cc: 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: [PATCH v3 2/2] iio: srf04: add power management feature Message-ID: <20200120164540.GA8725@arbad> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.10.1 (2018-07-13) X-Provags-ID: V03:K1:3hCyP3wz1c4WNIC8NGVeJsBSI1zAjBZAjz1ma3u4tSTLyexJTXg RLrVcj9jQSOjdNE9+ZeoZ8tOIKi2N3OoOVog1GXNx0AuH0CWIL3KQFIJMpf1AL/eSPXEuuS oUPOHFziMrpVaXjshUgdSfOILvbibmPRE5wVNdkIZJJzksXF6OOCFqOc2TPrD+0X918k816 6G2IUtfOKxDmTYKaWvkpA== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1;V03:K0:9G8UZvti0Co=:Z5lnGF5Gj3/IXYsIy9Zo7N wg4VefxQVSXyNAVIlSCwmzsY87jtd+7qm/aCSV/m4qL26dQVhALVQTFhRpoEekNFUpHK8lCJz hAPkWE9wHoyESRdqwxIiDV4SZCIIiUAJCNYgYVjYYOUvQcYXSeVbgbsohelcyr/J74HGVdC/5 VvGdGGJBdTFmhRDtnTOmdbjqF+u+ssDJseWlbA490Kj05JedEN8qIDjLtlAKGzpANIsaDYLTh X3yt/kQ7a4IjM07HqI64fXz/zu3CaAnGHLKpjqurWAWA1k5ggtn1Y9pIxfgpHF/9f8z4jQOy2 7ENy5Usn0IoJZNfBSYVcYCdFOBm/K5K2UVCYYuyjPc14P92U4hkLC6kcywFBzT5CGUDaFedml fLIs0Zl7cE4Iip+3I8G21mtWzHSHxHT+zRB0PjDhEhJW+ECeqcSEjEjo7xPqFieS53v0bhxIe DxlnZva8t4C8NhklCTpweU5IxKHW9vnLAXoBF0nYd8E1WbPA8NbVNC88BRgTdZ3TuHT62zxRA K6H6bDSQfaEOGFVXIfUnJCk9bgrMLZvFNngoWP6ICHT8Q+juz/che7gCw+PHVG6HQn5OY0egw q8/Eprkn5sllo/0TF1/Ic0WDq9a84b81hwoLQywMthX6wPUoKfCOzmDmKohewXKik3LA2ImS/ 1bheaTtRQMb1TDlIdZ3oTcN6OMhEmED7KTcyuTVivnRj6YldrIoP9uQspA4YAkxodWKvJc4OL iR/gd47Y7Iiu0Fk5hw1fJ5me2qxQXJS/k7BRI0EShUZu23JCt4gYfZoHzMa5XoIaAPml2mlkz 1hLYTtYab5hXMBCzJht6zF8lqozMrpttuk2md17WQaWh/Ubwx1tq3lO6cwRzOg9r4ecDpLfsS 86T/RWLB/JPbZukqkbqQ== Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org 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 --- 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, }, };