From 248ae1752e91438cb7cfc8432b88bc34410e8e4e Mon Sep 17 00:00:00 2001
From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Date: Fri, 29 Nov 2019 11:22:18 +0100
Subject: [PATCH] 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>
---
 drivers/gpio/gpiolib.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 43d98309e7256..36afe0b2b1500 100644
--- 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;
 }
-- 
2.30.2