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 80DEFC43441 for ; Tue, 13 Nov 2018 04:05:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3BAA422507 for ; Tue, 13 Nov 2018 04:05:40 +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="pOyIADKL" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3BAA422507 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 S1730772AbeKMOBu (ORCPT ); Tue, 13 Nov 2018 09:01:50 -0500 Received: from csm1.csm-office.com.au ([165.228.118.109]:40420 "EHLO sleepy.aussec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726103AbeKMOBt (ORCPT ); Tue, 13 Nov 2018 09:01:49 -0500 X-Greylist: delayed 1347 seconds by postgrey-1.27 at vger.kernel.org; Tue, 13 Nov 2018 09:01:47 EST X-Virus-Scanned: amavisd-new at aussec.com Received: from localhost.localdomain (dhcp-3-227.csm-office.com.au [172.16.3.227]) (authenticated bits=0) by sleepy.aussec.com (8.15.2/8.15.2) with ESMTPSA id wAD3gTrk014074 (version=TLSv1.2 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Tue, 13 Nov 2018 14:43:28 +1100 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=aussec.com; s=2016; t=1542080608; bh=VZ7PKCvCJplXiWW0zYPvltiJJ7HfFPUf0hJPdpUtBmY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=pOyIADKLWaMy+0rErp+Enltiz5ypxkGCiikm72rGmEKVRGMDXj2uKoUnpxsQac0oC sHL0VE+f3m06TOPEOnO5sD5MRQDFB3Opnnt2idnn1qyAgi+7Auf6ZoLHz0DSb1DRPO iNgMB8ozPqPEJxBxcX/Tzkcg+zkOSFzmVtn4dH5eGG4w+vuFR2WJJXjx7CE6coo3h+ /G2lPwdFMQAD1jJK/ijSYcoK3j/L0DGdU/UZXR8WaRymhbQFp0K6ikGpXMIrHixurs UOUTIy85DSeoQD7T+SYCZxKu0FRVp8A/iBBZFKE+wC3PFRCH20pnsil9teMqFNerr5 JVXuFubeBv8Fg== From: Tom Burkart To: Linux kernel mailing list Cc: Tom Burkart , Lukas Senger Subject: [PATCH v6 4/4] pps: pps-gpio pps-echo implementation Date: Tue, 13 Nov 2018 14:40:07 +1100 Message-Id: <20181113034007.3878-5-tom@aussec.com> X-Mailer: git-send-email 2.12.3 In-Reply-To: <20181113034007.3878-4-tom@aussec.com> References: <20181113034007.3878-1-tom@aussec.com> <20181113034007.3878-2-tom@aussec.com> <20181113034007.3878-3-tom@aussec.com> <20181113034007.3878-4-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 | 104 +++++++++++++++++++++++++++++++++++++++-- include/linux/pps-gpio.h | 3 ++ 2 files changed, 103 insertions(+), 4 deletions(-) diff --git a/drivers/pps/clients/pps-gpio.c b/drivers/pps/clients/pps-gpio.c index d25710883794..f5ffa2dc67b5 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 */ }; /* @@ -64,15 +72,54 @@ 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); + (!rising_edge && !info->assert_falling_edge))) + 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 unsigned long get_irqf_trigger_flags(const struct pps_gpio_device_data *data) { @@ -95,6 +142,7 @@ static int pps_gpio_probe(struct platform_device *pdev) int pps_default_params; const struct pps_gpio_platform_data *pdata = pdev->dev.platform_data; struct device_node *np = pdev->dev.of_node; + u32 value; /* allocate space for device info */ data = devm_kzalloc(&pdev->dev, sizeof(struct pps_gpio_device_data), @@ -104,10 +152,15 @@ static int pps_gpio_probe(struct platform_device *pdev) if (pdata) { data->gpio_pin = pdata->gpio_pin; + data->echo_pin = pdata->echo_pin; + if (pdata->echo_pin != NULL) + data->enable_pps_echo = true; gpio_label = pdata->gpio_label; 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 { /* GPIO setup */ data->gpio_pin = devm_gpiod_get(&pdev->dev, "pps", GPIOD_IN); @@ -117,11 +170,44 @@ static int pps_gpio_probe(struct platform_device *pdev) } gpio_label = PPS_GPIO_NAME; + 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; } /* IRQ setup */ @@ -141,6 +227,11 @@ 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; @@ -174,6 +265,11 @@ 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; } @@ -198,4 +294,4 @@ MODULE_AUTHOR("Ricardo Martins "); MODULE_AUTHOR("James Nuss "); MODULE_DESCRIPTION("Use GPIO pin as PPS source"); MODULE_LICENSE("GPL"); -MODULE_VERSION("1.0.0"); +MODULE_VERSION("1.1.0"); diff --git a/include/linux/pps-gpio.h b/include/linux/pps-gpio.h index 671a029fc80b..81c13d32ad0d 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; const char *gpio_label; }; -- 2.12.3