| Message ID | 1499073123-13393-1-git-send-email-brgl@bgdev.pl |
|---|---|
| State | New |
| Headers | show |
On Mon, Jul 3, 2017 at 12:12 PM, Bartosz Golaszewski <brgl@bgdev.pl> wrote: > 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. > struct lineevent_state *le = p; > struct gpioevent_data ge; > - int ret; > + int ret, level; I prefer int level; int ret; Though it's matter of taste (I don't remember which one Linus' preferable).
2017-07-03 13:07 GMT+02:00 Andy Shevchenko <andy.shevchenko@gmail.com>: > On Mon, Jul 3, 2017 at 12:12 PM, Bartosz Golaszewski <brgl@bgdev.pl> wrote: >> 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. > >> struct lineevent_state *le = p; >> struct gpioevent_data ge; >> - int ret; >> + int ret, level; > > I prefer > int level; > int ret; > > Though it's matter of taste (I don't remember which one Linus' preferable). > > -- > With Best Regards, > Andy Shevchenko Hard to tell, the file uses both styles. Thanks, Bartosz -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Jul 3, 2017 at 11:12 AM, Bartosz Golaszewski <brgl@bgdev.pl> wrote: > 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> > --- > Hi Linus, > > I tested my previous fix on a real board, where I got a storm of > interrupts from simply playing with a GPIO manually. It looked ok so I > posted the patch, but I didn't notice that when waiting for rising-edge > events, all falling-edge events got interpreted as such. This patch > should actually fix this bug. Tested carefully with gpio-mockup this > time. Patrch applied for fixes and tagged for stable. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index a42a1ee..2e96b3d 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -704,24 +704,23 @@ static irqreturn_t lineevent_irq_thread(int irq, void *p) { 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 {
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> --- Hi Linus, I tested my previous fix on a real board, where I got a storm of interrupts from simply playing with a GPIO manually. It looked ok so I posted the patch, but I didn't notice that when waiting for rising-edge events, all falling-edge events got interpreted as such. This patch should actually fix this bug. Tested carefully with gpio-mockup this time. drivers/gpio/gpiolib.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)