linux-kernel - [PATCH v4 5/5] gpio: sysfs: emit chardev line-state events on edge store

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20241031-gpio-notify-sysfs-v4-5-142021c2195c@linaro.org>
Date: Thu, 31 Oct 2024 21:01:55 +0100
From: Bartosz Golaszewski <brgl@...ev.pl>
To: Linus Walleij <linus.walleij@...aro.org>, 
 Bartosz Golaszewski <brgl@...ev.pl>, Kent Gibson <warthog618@...il.com>
Cc: linux-gpio@...r.kernel.org, linux-kernel@...r.kernel.org, 
 Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Subject: [PATCH v4 5/5] gpio: sysfs: emit chardev line-state events on edge
 store

From: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>

In order to emit line-state events on edge changes in sysfs, update the
EDGE flags in the descriptor in gpio_sysfs_request_irq() and emit the
event on a successful store.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
---
 drivers/gpio/gpiolib-sysfs.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index 49a5aa89cafc..5d7e8e64783c 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -179,12 +179,16 @@ static int gpio_sysfs_request_irq(struct device *dev, unsigned char flags)
 		return -ENODEV;
 
 	irq_flags = IRQF_SHARED;
-	if (flags & GPIO_IRQF_TRIGGER_FALLING)
+	if (flags & GPIO_IRQF_TRIGGER_FALLING) {
 		irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
 			IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
-	if (flags & GPIO_IRQF_TRIGGER_RISING)
+		set_bit(FLAG_EDGE_FALLING, &desc->flags);
+	}
+	if (flags & GPIO_IRQF_TRIGGER_RISING) {
 		irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
 			IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
+		set_bit(FLAG_EDGE_RISING, &desc->flags);
+	}
 
 	/*
 	 * FIXME: This should be done in the irq_request_resources callback
@@ -210,6 +214,8 @@ static int gpio_sysfs_request_irq(struct device *dev, unsigned char flags)
 err_unlock:
 	gpiochip_unlock_as_irq(guard.gc, gpio_chip_hwgpio(desc));
 err_put_kn:
+	clear_bit(FLAG_EDGE_RISING, &desc->flags);
+	clear_bit(FLAG_EDGE_FALLING, &desc->flags);
 	sysfs_put(data->value_kn);
 
 	return ret;
@@ -231,6 +237,8 @@ static void gpio_sysfs_free_irq(struct device *dev)
 	data->irq_flags = 0;
 	free_irq(data->irq, data);
 	gpiochip_unlock_as_irq(guard.gc, gpio_chip_hwgpio(desc));
+	clear_bit(FLAG_EDGE_RISING, &desc->flags);
+	clear_bit(FLAG_EDGE_FALLING, &desc->flags);
 	sysfs_put(data->value_kn);
 }
 
@@ -282,6 +290,8 @@ static ssize_t edge_store(struct device *dev,
 	if (status)
 		return status;
 
+	gpiod_line_state_notify(data->desc, GPIO_V2_LINE_CHANGED_CONFIG);
+
 	return size;
 }
 static DEVICE_ATTR_RW(edge);

-- 
2.45.2