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 C7079C43441 for ; Sat, 17 Nov 2018 13:07:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8623E2077C for ; Sat, 17 Nov 2018 13:07:10 +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="ghv4t0KT" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8623E2077C 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 S1726686AbeKQXXq (ORCPT ); Sat, 17 Nov 2018 18:23:46 -0500 Received: from csm1.csm-office.com.au ([165.228.118.109]:36506 "EHLO sleepy.aussec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726003AbeKQXXq (ORCPT ); Sat, 17 Nov 2018 18:23:46 -0500 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 wAHD5ubq015913 (version=TLSv1.2 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Sun, 18 Nov 2018 00:06:57 +1100 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=aussec.com; s=2016; t=1542460017; bh=JKhFj9PAdPBxAM8bEh48xJwnQX55OquUqso4evVzfRk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ghv4t0KTsjEHMZJLZvYYZwj4gxJBKOb5oy12adMBRj+2WjS8nv7owdY646+J/HD2F op9KXA9uqK7mAroWR1Ia2XrTOSAHAbglfWA4/3Fsm+l26O/CkJ7klTtjHsQNKxsTHx KEvBBj5AbvjIesC8tUZqmwxPq0mHCsvDcFHM/thbK05SxkPTfo+nBNWONriFYnMTEv qbrBa5VciKDEOzx0R8gO7uD2NEI5VH1v5L89fQpdzLEzgKRJeUCwL7p74GxQBk7Kav zU+vaCtklQbppOnwQRh15YKyvARYop74C87Y34jHtkurefpc5/V4BqOke7IAPGYPu/ xDk2ZqZXjiXeQ== From: Tom Burkart To: Linux kernel mailing list Cc: Tom Burkart , Lukas Senger Subject: [PATCH v8 4/4] pps: pps-gpio pps-echo implementation Date: Sun, 18 Nov 2018 00:03:37 +1100 Message-Id: <20181117130337.5856-5-tom@aussec.com> X-Mailer: git-send-email 2.12.3 In-Reply-To: <20181117130337.5856-4-tom@aussec.com> References: <20181117130337.5856-1-tom@aussec.com> <20181117130337.5856-2-tom@aussec.com> <20181117130337.5856-3-tom@aussec.com> <20181117130337.5856-4-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 | 102 +++++++++++++++++++++++++++++++++++++++-- include/linux/pps-gpio.h | 3 ++ 2 files changed, 102 insertions(+), 3 deletions(-) diff --git a/drivers/pps/clients/pps-gpio.c b/drivers/pps/clients/pps-gpio.c index d2fbc91dc8fc..fc12dd7a2cb3 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 +44,14 @@ 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; + bool invert_pps_echo; + unsigned int echo_active_ms; /* PPS echo active duration */ + unsigned long echo_timeout; /* timer timeout value in jiffies */ }; /* @@ -64,27 +72,72 @@ 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, + info->invert_pps_echo ? 0 : 1); + break; + + case PPS_CAPTURECLEAR: + if (pps->params.mode & PPS_ECHOCLEAR) + gpiod_set_value(info->echo_pin, + info->invert_pps_echo ? 0 : 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, + info->invert_pps_echo ? 1 : 0); +} + static int pps_gpio_setup(struct platform_device *pdev) { struct pps_gpio_device_data *data = platform_get_drvdata(pdev); const struct pps_gpio_platform_data *pdata = pdev->dev.platform_data; struct device_node *np = pdev->dev.of_node; int ret; + u32 value; 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->invert_pps_echo = pdata->invert_pps_echo; + data->echo_active_ms = pdata->echo_active_ms; } else { data->gpio_pin = devm_gpiod_get(&pdev->dev, NULL, /* request "gpios" */ @@ -95,11 +148,44 @@ static int pps_gpio_setup(struct platform_device *pdev) return PTR_ERR(data->gpio_pin); } + if (of_get_property(np, "echo-gpios", NULL)) { + 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; + } + if (of_get_property(np, "assert-falling-edge", NULL)) data->assert_falling_edge = true; if (of_get_property(np, "capture-clear", NULL)) data->capture_clear = true; + + if (of_get_property(np, "invert-pps-echo", NULL)) + data->invert_pps_echo = true; + } + /* sanity check on echo_active_ms */ + if (data->enable_pps_echo + && (!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; } return 0; } @@ -153,6 +239,11 @@ 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; @@ -185,6 +276,11 @@ 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, data->invert_pps_echo ? 1 : 0); + } dev_info(&pdev->dev, "removed IRQ %d as PPS source\n", data->irq); return 0; } @@ -209,4 +305,4 @@ 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..5390f18c73a5 100644 --- a/include/linux/pps-gpio.h +++ b/include/linux/pps-gpio.h @@ -24,8 +24,11 @@ struct pps_gpio_platform_data { struct gpio_desc *gpio_pin; + struct gpio_desc *echo_pin; bool assert_falling_edge; bool capture_clear; + bool invert_pps_echo; + unsigned int echo_active_ms; }; #endif /* _PPS_GPIO_H */ -- 2.12.3