The fwnode_irq_get_byname() was returning 0 at device-tree mapping
error. If this occurred, the KX022A driver did abort the probe but
errorneously directly returned the return value from
fwnode_irq_get_byname() from probe. In case of a device-tree mapping
error this indicated success.

The fwnode_irq_get_byname() has since been fixed to not return zero on
error so the check for fwnode_irq_get_byname() can be relaxed to only
treat negative values as errors. This will also do decent fix even when
backported to branches where fwnode_irq_get_byname() can still return
zero on error because KX022A probe should later fail at IRQ requesting
and a prober error handling should follow.

Relax the return value check for fwnode_irq_get_byname() to only treat
negative values as errors.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/r/202305110245.MFxC9bUj-lkp@intel.com/
Link: https://lore.kernel.org/r/202305110245.MFxC9bUj-lkp@intel.com/
Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Fixes: 7c1d1677b322 ("iio: accel: Support Kionix/ROHM KX022A accelerometer")
---
 drivers/iio/accel/kionix-kx022a.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/accel/kionix-kx022a.c b/drivers/iio/accel/kionix-kx022a.c
index f98393d74666..b8636fa8eaeb 100644
--- a/drivers/iio/accel/kionix-kx022a.c
+++ b/drivers/iio/accel/kionix-kx022a.c
@@ -1048,7 +1048,7 @@ int kx022a_probe_internal(struct device *dev)
 		data->ien_reg = KX022A_REG_INC4;
 	} else {
 		irq = fwnode_irq_get_byname(fwnode, "INT2");
-		if (irq <= 0)
+		if (irq < 0)
 			return dev_err_probe(dev, irq, "No suitable IRQ\n");
 
 		data->inc_reg = KX022A_REG_INC5;
-- 
2.40.1


-- 
Matti Vaittinen, Linux device drivers
ROHM Semiconductors, Finland SWDC
Kiviharjunlenkki 1E
90220 OULU
FINLAND

~~~ "I don't think so," said Rene Descartes. Just then he vanished ~~~
Simon says - in Latin please.
~~~ "non cogito me" dixit Rene Descarte, deinde evanescavit ~~~
Thanks to Simon Glass for the translation =] 

On Fri, 12 May 2023 10:53:41 +0300
Matti Vaittinen <mazziesaccount@gmail.com> wrote:

> The fwnode_irq_get_byname() was returning 0 at device-tree mapping
> error. If this occurred, the KX022A driver did abort the probe but
> errorneously directly returned the return value from
> fwnode_irq_get_byname() from probe. In case of a device-tree mapping
> error this indicated success.
> 
> The fwnode_irq_get_byname() has since been fixed to not return zero on
> error so the check for fwnode_irq_get_byname() can be relaxed to only
> treat negative values as errors. This will also do decent fix even when
> backported to branches where fwnode_irq_get_byname() can still return
> zero on error because KX022A probe should later fail at IRQ requesting
> and a prober error handling should follow.
On that basis I've picked this one up directly for the fixes-togreg branch of
iio.git and marked it for stable.

Thanks,

Jonathan

> 
> Relax the return value check for fwnode_irq_get_byname() to only treat
> negative values as errors.
> 
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Dan Carpenter <error27@gmail.com>
> Closes: https://lore.kernel.org/r/202305110245.MFxC9bUj-lkp@intel.com/
> Link: https://lore.kernel.org/r/202305110245.MFxC9bUj-lkp@intel.com/
> Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
> Fixes: 7c1d1677b322 ("iio: accel: Support Kionix/ROHM KX022A accelerometer")
> ---
>  drivers/iio/accel/kionix-kx022a.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/accel/kionix-kx022a.c b/drivers/iio/accel/kionix-kx022a.c
> index f98393d74666..b8636fa8eaeb 100644
> --- a/drivers/iio/accel/kionix-kx022a.c
> +++ b/drivers/iio/accel/kionix-kx022a.c
> @@ -1048,7 +1048,7 @@ int kx022a_probe_internal(struct device *dev)
>  		data->ien_reg = KX022A_REG_INC4;
>  	} else {
>  		irq = fwnode_irq_get_byname(fwnode, "INT2");
> -		if (irq <= 0)
> +		if (irq < 0)
>  			return dev_err_probe(dev, irq, "No suitable IRQ\n");
>  
>  		data->inc_reg = KX022A_REG_INC5;

On 5/13/23 21:44, Jonathan Cameron wrote:
> On Fri, 12 May 2023 10:53:41 +0300
> Matti Vaittinen <mazziesaccount@gmail.com> wrote:
> 
>> The fwnode_irq_get_byname() was returning 0 at device-tree mapping
>> error. If this occurred, the KX022A driver did abort the probe but
>> errorneously directly returned the return value from
>> fwnode_irq_get_byname() from probe. In case of a device-tree mapping
>> error this indicated success.
>>
>> The fwnode_irq_get_byname() has since been fixed to not return zero on
>> error so the check for fwnode_irq_get_byname() can be relaxed to only
>> treat negative values as errors. This will also do decent fix even when
>> backported to branches where fwnode_irq_get_byname() can still return
>> zero on error because KX022A probe should later fail at IRQ requesting
>> and a prober error handling should follow.
> On that basis I've picked this one up directly for the fixes-togreg branch of
> iio.git and marked it for stable.

Thanks for picking this up Jonathan. Although, the commit message is 
slightly misleading w/o the previous patches in this series because the 
fwnode_irq_get_byname() is fixed in the first patch.

Yours,
	-- Matti

-- 
Matti Vaittinen
Linux kernel developer at ROHM Semiconductors
Oulu Finland

~~ When things go utterly wrong vim users can always type :help! ~~