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

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.

Cc: stable@vger.kernel.org
Fixes: ad537b8225 ("gpiolib: fix filtering out unwanted events")
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Bartosz Golaszewski 2017-07-03 11:12:03 +02:00 committed by Linus Walleij
parent a589e211bd
commit df1e76f28f

View File

@ -704,24 +704,23 @@ static irqreturn_t lineevent_irq_thread(int irq, void *p)
{ {
struct lineevent_state *le = p; struct lineevent_state *le = p;
struct gpioevent_data ge; struct gpioevent_data ge;
int ret; int ret, level;
ge.timestamp = ktime_get_real_ns(); ge.timestamp = ktime_get_real_ns();
level = gpiod_get_value_cansleep(le->desc);
if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE
&& le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) { && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
int level = gpiod_get_value_cansleep(le->desc);
if (level) if (level)
/* Emit low-to-high event */ /* Emit low-to-high event */
ge.id = GPIOEVENT_EVENT_RISING_EDGE; ge.id = GPIOEVENT_EVENT_RISING_EDGE;
else else
/* Emit high-to-low event */ /* Emit high-to-low event */
ge.id = GPIOEVENT_EVENT_FALLING_EDGE; 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 */ /* Emit low-to-high event */
ge.id = GPIOEVENT_EVENT_RISING_EDGE; 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 */ /* Emit high-to-low event */
ge.id = GPIOEVENT_EVENT_FALLING_EDGE; ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
} else { } else {