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=-7.7 required=3.0 tests=DKIM_ADSP_ALL,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 06023C43381 for ; Fri, 22 Mar 2019 03:00:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B7D0721904 for ; Fri, 22 Mar 2019 03:00:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=aussec.com header.i=@aussec.com header.b="fs4gtqx+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727581AbfCVDAM (ORCPT ); Thu, 21 Mar 2019 23:00:12 -0400 Received: from csm1.csm-office.com.au ([165.228.118.109]:60196 "EHLO sleepy.aussec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727556AbfCVDAL (ORCPT ); Thu, 21 Mar 2019 23:00:11 -0400 X-Greylist: delayed 978 seconds by postgrey-1.27 at vger.kernel.org; Thu, 21 Mar 2019 23:00:05 EDT X-Virus-Scanned: amavisd-new at aussec.com Received: from hpdv6.aussec.com.com (c110-21-61-29.farfl4.nsw.optusnet.com.au [110.21.61.29]) (authenticated bits=0) by sleepy.aussec.com (8.15.2/8.15.2) with ESMTPSA id x2M2hAKY008721 (version=TLSv1.2 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Fri, 22 Mar 2019 13:43:36 +1100 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=aussec.com; s=2016; t=1553222616; bh=AL3Brqp9RXWGiJIzpj0mtMNPk7I6jNZwrunE+/uegVo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=fs4gtqx++GT1CxWZLdA+z1yTVWdqGRaSCPHG1tyvznWjw9SHJon1E22mAyoftE6Ko NzOOn1qkLL1xr32Of+49/hv4CIEXQunknR8sPpgbPs7agXrioozJ3xMiYbTePR8Evr OYjoy1VreuiRRZdAQ9wBpDiMsATTiG0G64lARvYWjsa0kcxHTnaPt/gzfQQ9oXdrow 8/9WfbM502IQ/R7N0oPEeru4Z1hL8MbfvWW4VZoAn7wNHxjBjQXfAIOb3mNcz312o8 5Nyepaq9zO34n1vaTyo9STXtbg1YXRpd5ZRLyA4UkAjOz3sZrUbEYvRdPFk031rkoN 9T+TwL6dWdntQ== From: Tom Burkart To: Linux kernel mailing list , Andrew Morton Cc: Tom Burkart , Rodolfo Giometti , Lukas Senger Subject: [PATCH v17 3/3] pps: pps-gpio pps-echo implementation Date: Fri, 22 Mar 2019 13:42:33 +1100 Message-Id: <20190322024233.17568-4-tom@aussec.com> X-Mailer: git-send-email 2.12.3 In-Reply-To: <20190322024233.17568-3-tom@aussec.com> References: <20190322024233.17568-1-tom@aussec.com> <20190322024233.17568-2-tom@aussec.com> <20190322024233.17568-3-tom@aussec.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch implements the PPS ECHO functionality for pps-gpio, that sysfs claims is available already. Configuration is done via device tree bindings. No changes are made to userspace interfaces. This patch was originally written by Lukas Senger as part of a masters thesis project and modified for inclusion into the linux kernel by Tom Burkart. Acked-by: Rodolfo Giometti Signed-off-by: Lukas Senger Signed-off-by: Tom Burkart --- drivers/pps/clients/pps-gpio.c | 88 ++++++++++++++++++++++++++++++++++++++++-- include/linux/pps-gpio.h | 2 + 2 files changed, 87 insertions(+), 3 deletions(-) diff --git a/drivers/pps/clients/pps-gpio.c b/drivers/pps/clients/pps-gpio.c index 4e5e9229814b..4b6418039387 100644 --- a/drivers/pps/clients/pps-gpio.c +++ b/drivers/pps/clients/pps-gpio.c @@ -35,6 +35,8 @@ #include #include #include +#include +#include /* Info for each registered platform device */ struct pps_gpio_device_data { @@ -42,8 +44,12 @@ struct pps_gpio_device_data { struct pps_device *pps; /* PPS source device */ struct pps_source_info info; /* PPS source information */ struct gpio_desc *gpio_pin; /* GPIO port descriptors */ + struct gpio_desc *echo_pin; + struct timer_list echo_timer; /* timer to reset echo active state */ bool assert_falling_edge; bool capture_clear; + unsigned int echo_active_ms; /* PPS echo active duration */ + unsigned long echo_timeout; /* timer timeout value in jiffies */ }; /* @@ -64,19 +70,56 @@ static irqreturn_t pps_gpio_irq_handler(int irq, void *data) rising_edge = gpiod_get_value(info->gpio_pin); if ((rising_edge && !info->assert_falling_edge) || (!rising_edge && info->assert_falling_edge)) - pps_event(info->pps, &ts, PPS_CAPTUREASSERT, NULL); + pps_event(info->pps, &ts, PPS_CAPTUREASSERT, data); else if (info->capture_clear && ((rising_edge && info->assert_falling_edge) || (!rising_edge && !info->assert_falling_edge))) - pps_event(info->pps, &ts, PPS_CAPTURECLEAR, NULL); + pps_event(info->pps, &ts, PPS_CAPTURECLEAR, data); return IRQ_HANDLED; } +/* This function will only be called when an ECHO GPIO is defined */ +static void pps_gpio_echo(struct pps_device *pps, int event, void *data) +{ + /* add_timer() needs to write into info->echo_timer */ + struct pps_gpio_device_data *info = data; + + switch (event) { + case PPS_CAPTUREASSERT: + if (pps->params.mode & PPS_ECHOASSERT) + gpiod_set_value(info->echo_pin, 1); + break; + + case PPS_CAPTURECLEAR: + if (pps->params.mode & PPS_ECHOCLEAR) + gpiod_set_value(info->echo_pin, 1); + break; + } + + /* fire the timer */ + if (info->pps->params.mode & (PPS_ECHOASSERT | PPS_ECHOCLEAR)) { + info->echo_timer.expires = jiffies + info->echo_timeout; + add_timer(&info->echo_timer); + } +} + +/* Timer callback to reset the echo pin to the inactive state */ +static void pps_gpio_echo_timer_callback(struct timer_list *t) +{ + const struct pps_gpio_device_data *info; + + info = from_timer(info, t, echo_timer); + + gpiod_set_value(info->echo_pin, 0); +} + static int pps_gpio_setup(struct platform_device *pdev) { struct pps_gpio_device_data *data = platform_get_drvdata(pdev); struct device_node *np = pdev->dev.of_node; + int ret; + u32 value; data->gpio_pin = devm_gpiod_get(&pdev->dev, NULL, /* request "gpios" */ @@ -87,6 +130,33 @@ static int pps_gpio_setup(struct platform_device *pdev) return PTR_ERR(data->gpio_pin); } + data->echo_pin = devm_gpiod_get_optional(&pdev->dev, + "echo", + GPIOD_OUT_LOW); + if (data->echo_pin) { + if (IS_ERR(data->echo_pin)) { + dev_err(&pdev->dev, "failed to request ECHO GPIO\n"); + return PTR_ERR(data->echo_pin); + } + + ret = of_property_read_u32(np, + "echo-active-ms", + &value); + if (ret) { + dev_err(&pdev->dev, + "failed to get echo-active-ms from OF\n"); + return ret; + } + data->echo_active_ms = value; + /* sanity check on echo_active_ms */ + if (!data->echo_active_ms || data->echo_active_ms > 999) { + dev_err(&pdev->dev, + "echo-active-ms: %u - bad value from OF\n", + data->echo_active_ms); + return -EINVAL; + } + } + if (of_property_read_bool(np, "assert-falling-edge")) data->assert_falling_edge = true; return 0; @@ -122,9 +192,11 @@ static int pps_gpio_probe(struct platform_device *pdev) /* GPIO setup */ if (pdata) { data->gpio_pin = pdata->gpio_pin; + data->echo_pin = pdata->echo_pin; data->assert_falling_edge = pdata->assert_falling_edge; data->capture_clear = pdata->capture_clear; + data->echo_active_ms = pdata->echo_active_ms; } else { ret = pps_gpio_setup(pdev); if (ret) @@ -148,6 +220,11 @@ static int pps_gpio_probe(struct platform_device *pdev) data->info.owner = THIS_MODULE; snprintf(data->info.name, PPS_MAX_NAME_LEN - 1, "%s.%d", pdev->name, pdev->id); + if (data->echo_pin) { + data->info.echo = pps_gpio_echo; + data->echo_timeout = msecs_to_jiffies(data->echo_active_ms); + timer_setup(&data->echo_timer, pps_gpio_echo_timer_callback, 0); + } /* register PPS source */ pps_default_params = PPS_CAPTUREASSERT | PPS_OFFSETASSERT; @@ -180,6 +257,11 @@ static int pps_gpio_remove(struct platform_device *pdev) struct pps_gpio_device_data *data = platform_get_drvdata(pdev); pps_unregister_source(data->pps); + if (data->echo_pin) { + del_timer_sync(&data->echo_timer); + /* reset echo pin in any case */ + gpiod_set_value(data->echo_pin, 0); + } dev_info(&pdev->dev, "removed IRQ %d as PPS source\n", data->irq); return 0; } @@ -204,4 +286,4 @@ MODULE_AUTHOR("Ricardo Martins "); MODULE_AUTHOR("James Nuss "); MODULE_DESCRIPTION("Use GPIO pin as PPS source"); MODULE_LICENSE("GPL"); -MODULE_VERSION("1.1.0"); +MODULE_VERSION("1.2.0"); diff --git a/include/linux/pps-gpio.h b/include/linux/pps-gpio.h index f028d2cda6f5..44171e6b7197 100644 --- a/include/linux/pps-gpio.h +++ b/include/linux/pps-gpio.h @@ -24,8 +24,10 @@ struct pps_gpio_platform_data { struct gpio_desc *gpio_pin; + struct gpio_desc *echo_pin; bool assert_falling_edge; bool capture_clear; + unsigned int echo_active_ms; }; #endif /* _PPS_GPIO_H */ -- 2.12.3