From patchwork Mon May 4 15:10:48 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 467652 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 76E6A1402AB for ; Tue, 5 May 2015 01:14:55 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b=jGiJeT2S; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752165AbbEDPOs (ORCPT ); Mon, 4 May 2015 11:14:48 -0400 Received: from mail-lb0-f174.google.com ([209.85.217.174]:34133 "EHLO mail-lb0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751555AbbEDPOn (ORCPT ); Mon, 4 May 2015 11:14:43 -0400 Received: by lbcga7 with SMTP id ga7so107225785lbc.1; Mon, 04 May 2015 08:14:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=cnCAJpX6AQPQp3YRyAg5gKXCSqzajtv7NAH6+Fpcwqw=; b=jGiJeT2SOAJ8VSsy1LyjRUnUEUj/c4tMKXGyGyFBWtKrSCEMq/RkZsu5Y6IGwH81IP ehTFZJe+MCdOtnQZkMM3ffhRruosOkB3NXS5qnDf++Y05N5DkxpotCx9qsEiJxXPDKxP ORbCBzs7b72Zi76gJVolAbgAV7hY+JxGaFshpC0HKfBUQ/qdyMcuFlv0aPEgkChcqkTt dsZAKUDLmAqvXTDvR5C9i7wI21tAEg4BP0N9p8sykwU/ryojR5FvrfjTBU7ypstvGwUA 9llEmO98oZEQH8Sielhtbk1aYBr/W7qi1XG2AkGEVSvfg/Og5dtV8hbALHCxIsON6vqA LwEw== X-Received: by 10.153.6.6 with SMTP id cq6mr20131594lad.13.1430752480453; Mon, 04 May 2015 08:14:40 -0700 (PDT) Received: from xi.terra (c193-14-96-226.cust.tele2.se. [193.14.96.226]) by mx.google.com with ESMTPSA id oy3sm3417488lbb.1.2015.05.04.08.14.39 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 04 May 2015 08:14:39 -0700 (PDT) Received: from johan by xi.terra with local (Exim 4.84) (envelope-from ) id 1YpI40-00043W-09; Mon, 04 May 2015 17:13:44 +0200 From: Johan Hovold To: Linus Walleij Cc: Alexandre Courbot , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold Subject: [PATCH v2 23/23] gpio: sysfs: move irq trigger flags to class-device data Date: Mon, 4 May 2015 17:10:48 +0200 Message-Id: <1430752248-15401-24-git-send-email-johan@kernel.org> X-Mailer: git-send-email 2.0.5 In-Reply-To: <1430752248-15401-1-git-send-email-johan@kernel.org> References: <1430752248-15401-1-git-send-email-johan@kernel.org> Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Move irq trigger flags, which as sysfs-interface specific, to the class device data. This avoids accessing the gpio-descriptor flags field using non-atomic operations without any locking, and allows for a more clear separation of the sysfs interface from gpiolib core. Signed-off-by: Johan Hovold --- drivers/gpio/gpiolib-sysfs.c | 47 ++++++++++++++++++++++---------------------- drivers/gpio/gpiolib.h | 4 ---- 2 files changed, 24 insertions(+), 27 deletions(-) diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c index 9047b2d556a0..b57ed8e55ab5 100644 --- a/drivers/gpio/gpiolib-sysfs.c +++ b/drivers/gpio/gpiolib-sysfs.c @@ -10,12 +10,18 @@ #include "gpiolib.h" +#define GPIO_IRQF_TRIGGER_FALLING BIT(0) +#define GPIO_IRQF_TRIGGER_RISING BIT(1) +#define GPIO_IRQF_TRIGGER_BOTH (GPIO_IRQF_TRIGGER_FALLING | \ + GPIO_IRQF_TRIGGER_RISING) + struct gpiod_data { struct gpio_desc *desc; struct mutex mutex; struct kernfs_node *value_kn; int irq; + unsigned char irq_flags; bool direction_can_change; }; @@ -143,7 +149,7 @@ static irqreturn_t gpio_sysfs_irq(int irq, void *priv) } /* Caller holds gpiod-data mutex. */ -static int gpio_sysfs_request_irq(struct device *dev, unsigned long gpio_flags) +static int gpio_sysfs_request_irq(struct device *dev, unsigned char flags) { struct gpiod_data *data = dev_get_drvdata(dev); struct gpio_desc *desc = data->desc; @@ -159,10 +165,10 @@ static int gpio_sysfs_request_irq(struct device *dev, unsigned long gpio_flags) return -ENODEV; irq_flags = IRQF_SHARED; - if (test_bit(FLAG_TRIG_FALL, &gpio_flags)) + if (flags & GPIO_IRQF_TRIGGER_FALLING) irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING; - if (test_bit(FLAG_TRIG_RISE, &gpio_flags)) + if (flags & GPIO_IRQF_TRIGGER_RISING) irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING; @@ -183,7 +189,7 @@ static int gpio_sysfs_request_irq(struct device *dev, unsigned long gpio_flags) if (ret < 0) goto err_unlock; - desc->flags |= gpio_flags; + data->irq_flags = flags; return 0; @@ -204,7 +210,7 @@ static void gpio_sysfs_free_irq(struct device *dev) struct gpiod_data *data = dev_get_drvdata(dev); struct gpio_desc *desc = data->desc; - desc->flags &= ~GPIO_TRIGGER_MASK; + data->irq_flags = 0; free_irq(data->irq, data); gpiochip_unlock_as_irq(desc->chip, gpio_chip_hwgpio(desc)); sysfs_put(data->value_kn); @@ -212,28 +218,25 @@ static void gpio_sysfs_free_irq(struct device *dev) static const struct { const char *name; - unsigned long flags; + unsigned char flags; } trigger_types[] = { { "none", 0 }, - { "falling", BIT(FLAG_TRIG_FALL) }, - { "rising", BIT(FLAG_TRIG_RISE) }, - { "both", BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE) }, + { "falling", GPIO_IRQF_TRIGGER_FALLING }, + { "rising", GPIO_IRQF_TRIGGER_RISING }, + { "both", GPIO_IRQF_TRIGGER_BOTH }, }; static ssize_t edge_show(struct device *dev, struct device_attribute *attr, char *buf) { struct gpiod_data *data = dev_get_drvdata(dev); - struct gpio_desc *desc = data->desc; - unsigned long mask; ssize_t status = 0; int i; mutex_lock(&data->mutex); for (i = 0; i < ARRAY_SIZE(trigger_types); i++) { - mask = desc->flags & GPIO_TRIGGER_MASK; - if (mask == trigger_types[i].flags) { + if (data->irq_flags == trigger_types[i].flags) { status = sprintf(buf, "%s\n", trigger_types[i].name); break; } @@ -248,8 +251,7 @@ static ssize_t edge_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { struct gpiod_data *data = dev_get_drvdata(dev); - struct gpio_desc *desc = data->desc; - unsigned long flags; + unsigned char flags; ssize_t status = size; int i; @@ -265,12 +267,12 @@ static ssize_t edge_store(struct device *dev, mutex_lock(&data->mutex); - if ((desc->flags & GPIO_TRIGGER_MASK) == flags) { + if (flags == data->irq_flags) { status = size; goto out_unlock; } - if (desc->flags & GPIO_TRIGGER_MASK) + if (data->irq_flags) gpio_sysfs_free_irq(dev); if (flags) { @@ -292,6 +294,7 @@ static int gpio_sysfs_set_active_low(struct device *dev, int value) struct gpiod_data *data = dev_get_drvdata(dev); struct gpio_desc *desc = data->desc; int status = 0; + unsigned int flags = data->irq_flags; if (!!test_bit(FLAG_ACTIVE_LOW, &desc->flags) == !!value) return 0; @@ -302,12 +305,10 @@ static int gpio_sysfs_set_active_low(struct device *dev, int value) clear_bit(FLAG_ACTIVE_LOW, &desc->flags); /* reconfigure poll(2) support if enabled on one edge only */ - if (!!test_bit(FLAG_TRIG_RISE, &desc->flags) ^ - !!test_bit(FLAG_TRIG_FALL, &desc->flags)) { - unsigned long trigger_flags = desc->flags & GPIO_TRIGGER_MASK; - + if (flags == GPIO_IRQF_TRIGGER_FALLING || + flags == GPIO_IRQF_TRIGGER_RISING) { gpio_sysfs_free_irq(dev); - status = gpio_sysfs_request_irq(dev, trigger_flags); + status = gpio_sysfs_request_irq(dev, flags); } return status; @@ -700,7 +701,7 @@ void gpiod_unexport(struct gpio_desc *desc) /* * Release irq after deregistration to prevent race with edge_store. */ - if (desc->flags & GPIO_TRIGGER_MASK) + if (data->irq_flags) gpio_sysfs_free_irq(dev); mutex_unlock(&sysfs_lock); diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h index 34eea33e482c..42c2ede96545 100644 --- a/drivers/gpio/gpiolib.h +++ b/drivers/gpio/gpiolib.h @@ -81,16 +81,12 @@ struct gpio_desc { #define FLAG_IS_OUT 1 #define FLAG_EXPORT 2 /* protected by sysfs_lock */ #define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */ -#define FLAG_TRIG_FALL 4 /* trigger on falling edge */ -#define FLAG_TRIG_RISE 5 /* trigger on rising edge */ #define FLAG_ACTIVE_LOW 6 /* value has active low */ #define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */ #define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */ #define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */ #define FLAG_IS_HOGGED 11 /* GPIO is hogged */ -#define GPIO_TRIGGER_MASK (BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE)) - const char *label; };