gpiolib: emit a debug message when adding events to a full kfifo

Currently if the line-event kfifo is full, we just silently drop any new
events. Add a ratelimited debug message so that we at least have some
trace in the kernel log of event overflow.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 43d9830..36afe0b 100644 (file)
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -978,6 +978,8 @@ static irqreturn_t lineevent_irq_thread(int irq, void *p)
                                            1, &le->wait.lock);
        if (ret)
                wake_up_poll(&le->wait, EPOLLIN);
+       else
+               pr_debug_ratelimited("event FIFO is full - event dropped\n");
 
        return IRQ_HANDLED;
 }