Messages in this thread Patch in this message | | | From | Sasha Levin <> | Subject | [PATCH AUTOSEL 5.15 40/41] gpio: grgpio: Fix device removing | Date | Mon, 27 Jun 2022 22:20:59 -0400 |
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From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
[ Upstream commit c1c2a15c2b5379ea8e44dcdcc298e3de42076ba0 ]
If a platform device's remove callback returns non-zero, the device core emits a warning and still removes the device and calls the devm cleanup callbacks.
So it's not save to not unregister the gpiochip because on the next request to a GPIO the driver accesses kfree()'d memory. Also if an IRQ triggers, the freed memory is accessed.
Instead rely on the GPIO framework to ensure that after gpiochip_remove() all GPIOs are freed and so the corresponding IRQs are unmapped.
This is a preparation for making platform remove callbacks return void.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/gpio/gpio-grgpio.c | 14 +------------- 1 file changed, 1 insertion(+), 13 deletions(-)
diff --git a/drivers/gpio/gpio-grgpio.c b/drivers/gpio/gpio-grgpio.c index f954359c9544..46f6158d1c71 100644 --- a/drivers/gpio/gpio-grgpio.c +++ b/drivers/gpio/gpio-grgpio.c @@ -435,25 +435,13 @@ static int grgpio_probe(struct platform_device *ofdev) static int grgpio_remove(struct platform_device *ofdev) { struct grgpio_priv *priv = platform_get_drvdata(ofdev); - int i; - int ret = 0; - - if (priv->domain) { - for (i = 0; i < GRGPIO_MAX_NGPIO; i++) { - if (priv->uirqs[i].refcnt != 0) { - ret = -EBUSY; - goto out; - } - } - } gpiochip_remove(&priv->gc); if (priv->domain) irq_domain_remove(priv->domain); -out: - return ret; + return 0; } static const struct of_device_id grgpio_match[] = { -- 2.35.1
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