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=-7.6 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,T_MIXED_ES,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 0F7DFC65BAE for ; Fri, 14 Dec 2018 02:32:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BFC4E2086D for ; Fri, 14 Dec 2018 02:32:06 +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="vkAwf3Wo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BFC4E2086D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=aussec.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729330AbeLNCcF (ORCPT ); Thu, 13 Dec 2018 21:32:05 -0500 Received: from csm1.csm-office.com.au ([165.228.118.109]:38708 "EHLO sleepy.aussec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729250AbeLNCcA (ORCPT ); Thu, 13 Dec 2018 21:32:00 -0500 X-Virus-Scanned: amavisd-new at aussec.com Received: from localhost.localdomain ([1.128.229.148]) (authenticated bits=0) by sleepy.aussec.com (8.15.2/8.15.2) with ESMTPSA id wBE2UxcE004738 (version=TLSv1.2 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Fri, 14 Dec 2018 13:31:33 +1100 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=aussec.com; s=2016; t=1544754694; bh=vlqXIxxwLTH77D93HQG3sPOxtpN2R8BaYvqnwtHn6/M=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=vkAwf3WovFd0bN5ZGHHTvutGUAhV6P2VUGQcQygTczCtYRu//rr28JcJqQ8Vit29U eu5dP1rM5QpnRaCJvE8FKsZyDpGNbLAHhJOfnPZKSuCQb1Fn5JeJjMCcxxAhOXOz4r fb8FJaZ98wCJ6EPI7w8VKMO3XwXh57bEImXljP1XqAf50b9p9OeE8+ADpugv/ICL5m Y+fILTmKurcT6RPLhHYFMNaJFss4OZ9ZByER68bdZGClBu6EoxGfdcKul43jCgi9FZ MNSKIWfWXWF72+w7VRPi53QgL5rI2ZVwihrqHg1QV+/FLDNEsS/uoTyKTAk5z/FblZ ppIyiYxwyL7Dg== From: Tom Burkart To: Linux kernel mailing list Cc: Tom Burkart , Rodolfo Giometti , Ricardo Martins , James Nuss , Lukas Senger Subject: [PATCH v13 3/3] pps: pps-gpio pps-echo implementation Date: Fri, 14 Dec 2018 13:30:19 +1100 Message-Id: <20181214023019.18805-4-tom@aussec.com> X-Mailer: git-send-email 2.12.3 In-Reply-To: <20181214023019.18805-3-tom@aussec.com> References: <20181214023019.18805-1-tom@aussec.com> <20181214023019.18805-2-tom@aussec.com> <20181214023019.18805-3-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. 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. Signed-off-by: Lukas Senger Signed-off-by: Tom Burkart --- drivers/pps/clients/pps-gpio.c | 94 ++++++++++++++++++++++++++++++++++++++++-- include/linux/pps-gpio.h | 2 + 2 files changed, 93 insertions(+), 3 deletions(-) diff --git a/drivers/pps/clients/pps-gpio.c b/drivers/pps/clients/pps-gpio.c index 5d764dceabc5..b239c4b9ff51 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 +44,13 @@ 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; + bool enable_pps_echo; + unsigned int echo_active_ms; /* PPS echo active duration */ + unsigned long echo_timeout; /* timer timeout value in jiffies */ }; /* @@ -64,19 +71,57 @@ 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; } +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; + + 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 +132,35 @@ static int pps_gpio_setup(struct platform_device *pdev) return PTR_ERR(data->gpio_pin); } + if (of_property_read_bool(np, "echo-gpios")) { + data->enable_pps_echo = true; + + data->echo_pin = devm_gpiod_get(&pdev->dev, + "echo", + GPIOD_OUT_LOW); + 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 +196,13 @@ 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; + if (pdata->echo_pin != NULL) + data->enable_pps_echo = true; 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 +226,11 @@ 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->enable_pps_echo) { + 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 +263,11 @@ 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->enable_pps_echo) { + 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 +292,4 @@ 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