The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 03a58ea5905fdbd93ff9e52e670d802600ba38cd Mon Sep 17 00:00:00 2001

From: Kent Gibson warthog618@gmail.com Date: Thu, 21 Jan 2021 22:10:38 +0800 Subject: [PATCH] gpiolib: cdev: clear debounce period if line set to output

When set_config changes a line from input to output debounce is implicitly disabled, as debounce makes no sense for outputs, but the debounce period is not being cleared and is still reported in the line info.

So clear the debounce period when the debouncer is stopped in edge_detector_stop().

Fixes: 65cff7046406 ("gpiolib: cdev: support setting debounce") Cc: stable@vger.kernel.org Signed-off-by: Kent Gibson warthog618@gmail.com Reviewed-by: Linus Walleij linus.walleij@linaro.org Signed-off-by: Bartosz Golaszewski bgolaszewski@baylibre.com

diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index 1a7b51163528..1631727bf0da 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -776,6 +776,8 @@ static void edge_detector_stop(struct line *line) cancel_delayed_work_sync(&line->work); WRITE_ONCE(line->sw_debounced, 0); WRITE_ONCE(line->eflags, 0); + if (line->desc) + WRITE_ONCE(line->desc->debounce_period_us, 0); /* do not change line->level - see comment in debounced_value() */ }