Add the missing check for platform_get_irq() and return error
if it fails.
The returned error code will be dealed with in
module_platform_driver(ath79_gpio_driver) and the driver will not
be registered.

Fixes: 2b8f89e19b6d ("gpio: ath79: Add support for the interrupt controller")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
Changelog:

v2 -> v3:

1. Check before assigning values.

v1 -> v2:

1. Return "girq->parents[0]" instead of "-ENODEV".
---
 drivers/gpio/gpio-ath79.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-ath79.c b/drivers/gpio/gpio-ath79.c
index aa0a954b8392..d2d838ad33bb 100644
--- a/drivers/gpio/gpio-ath79.c
+++ b/drivers/gpio/gpio-ath79.c
@@ -285,7 +285,10 @@ static int ath79_gpio_probe(struct platform_device *pdev)
 					     GFP_KERNEL);
 		if (!girq->parents)
 			return -ENOMEM;
-		girq->parents[0] = platform_get_irq(pdev, 0);
+		err = platform_get_irq(pdev, 0);
+		if (err < 0)
+			return err;
+		girq->parents[0] = err;
 		girq->default_type = IRQ_TYPE_NONE;
 		girq->handler = handle_simple_irq;
 	}
-- 
2.25.1

Tue, Jun 06, 2023 at 11:18:41AM +0800, Jiasheng Jiang kirjoitti:

Is this v4?

> Add the missing check for platform_get_irq() and return error
> if it fails.
> The returned error code will be dealed with in
> module_platform_driver(ath79_gpio_driver) and the driver will not
> be registered.

No, this functional change and has not to be for the fixes unless _this_ is the
regression you are fixing. Did the driver work before at some point as after
this change?

Otherwise you have to _justify_ that this functional change won't break
existing setups (with broked IRQ in Device Tree, for example).

-- 
With Best Regards,
Andy Shevchenko

Tue, Jun 06, 2023 at 12:28:17PM +0300, andy.shevchenko@gmail.com kirjoitti:
> Tue, Jun 06, 2023 at 11:18:41AM +0800, Jiasheng Jiang kirjoitti:
> 
> Is this v4?
> 
> > Add the missing check for platform_get_irq() and return error
> > if it fails.
> > The returned error code will be dealed with in
> > module_platform_driver(ath79_gpio_driver) and the driver will not
> > be registered.
> 
> No, this functional change and has not to be for the fixes unless _this_ is the
> regression you are fixing. Did the driver work before at some point as after
> this change?

To be more clear, answer to the following questions:
1) does driver work with wrong DT configuration?
2a) if yes, does it make sense, i.e. the hardware functioning usefully?
2b) if yes, can we guarantee there are no broken configurations in the wild?

Depending on the answers correct your code and/or commit message.

> Otherwise you have to _justify_ that this functional change won't break
> existing setups (with broked IRQ in Device Tree, for example).

-- 
With Best Regards,
Andy Shevchenko