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gpio: grgpio: Fix device removing

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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>
This commit is contained in:
Uwe Kleine-König 2022-06-21 08:40:36 +02:00 committed by Bartosz Golaszewski
parent 9ca766eaea
commit c1c2a15c2b
1 changed files with 1 additions and 13 deletions
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14
drivers/gpio/gpio-grgpio.c
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@ -434,25 +434,13 @@ static int grgpio_probe(struct platform_device *ofdev)
static int grgpio_remove(struct platform_device *ofdev) static int grgpio_remove(struct platform_device *ofdev)
{ {
struct grgpio_priv *priv = platform_get_drvdata(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); gpiochip_remove(&priv->gc);
if (priv->domain) if (priv->domain)
irq_domain_remove(priv->domain); irq_domain_remove(priv->domain);
out: return 0;
return ret;
} }
static const struct of_device_id grgpio_match[] = { static const struct of_device_id grgpio_match[] = {