From patchwork Tue Apr 21 15:42:31 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 463366 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 36A2614011D for ; Wed, 22 Apr 2015 01:46:33 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=fail reason="verification failed; unprotected key" header.d=gmail.com header.i=@gmail.com header.b=qqliixQk; dkim-adsp=none (unprotected policy); dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932807AbbDUPoF (ORCPT ); Tue, 21 Apr 2015 11:44:05 -0400 Received: from mail-lb0-f171.google.com ([209.85.217.171]:32822 "EHLO mail-lb0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755493AbbDUPoC (ORCPT ); Tue, 21 Apr 2015 11:44:02 -0400 Received: by lbbzk7 with SMTP id zk7so159001626lbb.0; Tue, 21 Apr 2015 08:44:00 -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=NgFUhZvz0SeH4j/JDJpRhITp049cCFY4WhVsarccqTc=; b=qqliixQkxk7Vz98JrNhJEifdT56Ot33xVqerUl4UoTcWlShwfycE9M5I3jplmxIfHw NHBR+l8tJq/0DmE8lo+v8MYRw4huXQ6vvPLNxYfShfDWc/9PYhOWxmq3xdB3CwBF5vyw FX70rWLY5zLs4USa7LfuHgJjSiABvB7d90A7I2T0nK5P2dSDgr5AVJfdwYBJFr5qRj6P YWZGm+/yJkBarHEG8C8MAxjvommHaYBqG1v4X1DwUV05F9sVKudpYQYMxZzVvhO711wH HbX+6LlCUQm/t4tFky0G3mtY5mGq10ix87VXDzCPfkiYBBxTKLwa0t6jztJHwWKfbbx9 APtg== X-Received: by 10.112.199.1 with SMTP id jg1mr20661890lbc.59.1429631040359; Tue, 21 Apr 2015 08:44:00 -0700 (PDT) Received: from xi.terra (c193-14-96-226.cust.tele2.se. [193.14.96.226]) by mx.google.com with ESMTPSA id f2sm479012lah.39.2015.04.21.08.43.59 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 21 Apr 2015 08:43:59 -0700 (PDT) Received: from johan by xi.terra with local (Exim 4.84) (envelope-from ) id 1YkaKN-00075c-Jg; Tue, 21 Apr 2015 17:43:11 +0200 From: Johan Hovold To: Linus Walleij Cc: Alexandre Courbot , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold Subject: [PATCH 23/23] gpio: sysfs: move irq trigger flags to class-device data Date: Tue, 21 Apr 2015 17:42:31 +0200 Message-Id: <1429630951-27082-24-git-send-email-johan@kernel.org> X-Mailer: git-send-email 2.0.5 In-Reply-To: <1429630951-27082-1-git-send-email-johan@kernel.org> References: <1429630951-27082-1-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 | 48 ++++++++++++++++++++++---------------------- drivers/gpio/gpiolib.h | 4 ---- 2 files changed, 24 insertions(+), 28 deletions(-) diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c index 27a8c84fc241..8786b8b79ce6 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; @@ -171,7 +177,7 @@ static int gpio_sysfs_request_irq(struct device *dev, unsigned long gpio_flags) if (ret < 0) goto err_put_kn; - desc->flags |= gpio_flags; + data->irq_flags = flags; return 0; @@ -188,37 +194,33 @@ err_put_kn: 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); sysfs_put(data->value_kn); } 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; } @@ -233,8 +235,7 @@ 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; @@ -250,12 +251,12 @@ 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) { @@ -277,6 +278,7 @@ 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; @@ -287,12 +289,10 @@ 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; @@ -685,7 +685,7 @@ 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 591257a4359a..e048be7d1f5e 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; };