Patch "gpiolib: skip unwanted events, don't convert them to opposite edge" has been added to the 4.9-stable tree

Patch "gpiolib: skip unwanted events, don't convert them to opposite edge" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    gpiolib: skip unwanted events, don't convert them to opposite edge

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     gpiolib-skip-unwanted-events-don-t-convert-them-to-opposite-edge.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From df1e76f28ffe87d1b065eecab2d0fbb89e6bdee5 Mon Sep 17 00:00:00 2001
From: Bartosz Golaszewski <brgl@bgdev.pl>
Date: Mon, 3 Jul 2017 11:12:03 +0200
Subject: gpiolib: skip unwanted events, don't convert them to opposite edge

From: Bartosz Golaszewski <brgl@bgdev.pl>

commit df1e76f28ffe87d1b065eecab2d0fbb89e6bdee5 upstream.

The previous fix for filtering out of unwatched events was not entirely
correct. Instead of skipping the events we don't want, they are now
interpreted as events with opposing edge.

In order to fix it: always read the GPIO line value on interrupt and
only emit the event if it corresponds with the event type we requested.

Fixes: ad537b822577 ("gpiolib: fix filtering out unwanted events")
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpio/gpiolib.c |    9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -703,24 +703,23 @@ static irqreturn_t lineevent_irq_thread(
 {
 	struct lineevent_state *le = p;
 	struct gpioevent_data ge;
-	int ret;
+	int ret, level;
 
 	ge.timestamp = ktime_get_real_ns();
+	level = gpiod_get_value_cansleep(le->desc);
 
 	if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE
 	    && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
-		int level = gpiod_get_value_cansleep(le->desc);
-
 		if (level)
 			/* Emit low-to-high event */
 			ge.id = GPIOEVENT_EVENT_RISING_EDGE;
 		else
 			/* Emit high-to-low event */
 			ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
-	} else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) {
+	} else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE && level) {
 		/* Emit low-to-high event */
 		ge.id = GPIOEVENT_EVENT_RISING_EDGE;
-	} else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
+	} else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE && !level) {
 		/* Emit high-to-low event */
 		ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
 	} else {


Patches currently in stable-queue which might be from brgl@bgdev.pl are

queue-4.9/gpiolib-skip-unwanted-events-don-t-convert-them-to-opposite-edge.patch