[PATCH -next] I2C: Use helper function IS_ERR_OR_NULL()

[PATCH -next] I2C: Use helper function IS_ERR_OR_NULL()

[Ruan Jinjie]

Use IS_ERR_OR_NULL() instead of open-coding it
to simplify the code.

Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
---
 drivers/i2c/busses/i2c-at91-master.c | 2 +-
 drivers/i2c/busses/i2c-imx.c         | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c
index 94cff1cd527e..0e454c04a145 100644
--- a/drivers/i2c/busses/i2c-at91-master.c
+++ b/drivers/i2c/busses/i2c-at91-master.c
@@ -831,7 +831,7 @@ static int at91_init_twi_recovery_gpio(struct platform_device *pdev,
 	struct i2c_bus_recovery_info *rinfo = &dev->rinfo;
 
 	rinfo->pinctrl = devm_pinctrl_get(&pdev->dev);
-	if (!rinfo->pinctrl || IS_ERR(rinfo->pinctrl)) {
+	if (IS_ERR_OR_NULL(rinfo->pinctrl)) {
 		dev_info(dev->dev, "can't get pinctrl, bus recovery not supported\n");
 		return PTR_ERR(rinfo->pinctrl);
 	}
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 10e89586ca72..8807c90df749 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -1388,7 +1388,7 @@ static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
 	struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
 
 	i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
-	if (!i2c_imx->pinctrl || IS_ERR(i2c_imx->pinctrl)) {
+	if (!IS_ERR_OR_NULL(i2c_imx->pinctrl)) {
 		dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n");
 		return PTR_ERR(i2c_imx->pinctrl);
 	}
-- 
2.34.1

Re: [PATCH -next] I2C: Use helper function IS_ERR_OR_NULL()

[Ruan Jinjie]

On 2023/8/16 17:46, Ruan Jinjie wrote:
> Use IS_ERR_OR_NULL() instead of open-coding it
> to simplify the code.
> 
> Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
> ---
>  drivers/i2c/busses/i2c-at91-master.c | 2 +-
>  drivers/i2c/busses/i2c-imx.c         | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c
> index 94cff1cd527e..0e454c04a145 100644
> --- a/drivers/i2c/busses/i2c-at91-master.c
> +++ b/drivers/i2c/busses/i2c-at91-master.c
> @@ -831,7 +831,7 @@ static int at91_init_twi_recovery_gpio(struct platform_device *pdev,
>  	struct i2c_bus_recovery_info *rinfo = &dev->rinfo;
>  
>  	rinfo->pinctrl = devm_pinctrl_get(&pdev->dev);
> -	if (!rinfo->pinctrl || IS_ERR(rinfo->pinctrl)) {
> +	if (IS_ERR_OR_NULL(rinfo->pinctrl)) {
>  		dev_info(dev->dev, "can't get pinctrl, bus recovery not supported\n");
>  		return PTR_ERR(rinfo->pinctrl);
>  	}
> diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> index 10e89586ca72..8807c90df749 100644
> --- a/drivers/i2c/busses/i2c-imx.c
> +++ b/drivers/i2c/busses/i2c-imx.c
> @@ -1388,7 +1388,7 @@ static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
>  	struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
>  
>  	i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
> -	if (!i2c_imx->pinctrl || IS_ERR(i2c_imx->pinctrl)) {
> +	if (!IS_ERR_OR_NULL(i2c_imx->pinctrl)) {

Sorry, there is a problem, please ignore it.

>  		dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n");
>  		return PTR_ERR(i2c_imx->pinctrl);
>  	}

Re: [PATCH -next] I2C: Use helper function IS_ERR_OR_NULL()

[Yann Sionneau]

Le 16/08/2023 à 11:46, Ruan Jinjie a écrit :

> Use IS_ERR_OR_NULL() instead of open-coding it
> to simplify the code.
>   
>   	rinfo->pinctrl = devm_pinctrl_get(&pdev->dev);
> -	if (!rinfo->pinctrl || IS_ERR(rinfo->pinctrl)) {
> +	if (IS_ERR_OR_NULL(rinfo->pinctrl)) {

Can the return of devm_pinctrl_get really be NULL?

Regards,

-- 

Yann

Re: [PATCH -next] I2C: Use helper function IS_ERR_OR_NULL()

[Russell King (Oracle)]

On Wed, Aug 16, 2023 at 05:48:34PM +0800, Ruan Jinjie wrote:
> 
> 
> On 2023/8/16 17:46, Ruan Jinjie wrote:
> > Use IS_ERR_OR_NULL() instead of open-coding it
> > to simplify the code.
> > 
> > Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
> > ---
> >  drivers/i2c/busses/i2c-at91-master.c | 2 +-
> >  drivers/i2c/busses/i2c-imx.c         | 2 +-
> >  2 files changed, 2 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c
> > index 94cff1cd527e..0e454c04a145 100644
> > --- a/drivers/i2c/busses/i2c-at91-master.c
> > +++ b/drivers/i2c/busses/i2c-at91-master.c
> > @@ -831,7 +831,7 @@ static int at91_init_twi_recovery_gpio(struct platform_device *pdev,
> >  	struct i2c_bus_recovery_info *rinfo = &dev->rinfo;
> >  
> >  	rinfo->pinctrl = devm_pinctrl_get(&pdev->dev);
> > -	if (!rinfo->pinctrl || IS_ERR(rinfo->pinctrl)) {
> > +	if (IS_ERR_OR_NULL(rinfo->pinctrl)) {
> >  		dev_info(dev->dev, "can't get pinctrl, bus recovery not supported\n");
> >  		return PTR_ERR(rinfo->pinctrl);
> >  	}
> > diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> > index 10e89586ca72..8807c90df749 100644
> > --- a/drivers/i2c/busses/i2c-imx.c
> > +++ b/drivers/i2c/busses/i2c-imx.c
> > @@ -1388,7 +1388,7 @@ static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
> >  	struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
> >  
> >  	i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
> > -	if (!i2c_imx->pinctrl || IS_ERR(i2c_imx->pinctrl)) {
> > +	if (!IS_ERR_OR_NULL(i2c_imx->pinctrl)) {
> 
> Sorry, there is a problem, please ignore it.

I don't think these conversions are appropriate for devm_pinctrl_get().
If one reads the code for devm_pinctrl_get() and pinctrl_get(), then
one finds that it will never return NULL.

So the tests for NULL do not serve any practical purpose than giving
coders a warm fuzzy feeling that they've tested for a NULL pointer.
Practically, they are of no use, so should be removed... thus making
the conversion to IS_ERR_OR_NULL() irrelevant.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH -next] I2C: Use helper function IS_ERR_OR_NULL()

[Russell King (Oracle)]

On Wed, Aug 16, 2023 at 05:46:18PM +0800, Ruan Jinjie wrote:
> Use IS_ERR_OR_NULL() instead of open-coding it
> to simplify the code.
> 
> Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
> ---
>  drivers/i2c/busses/i2c-at91-master.c | 2 +-
>  drivers/i2c/busses/i2c-imx.c         | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c
> index 94cff1cd527e..0e454c04a145 100644
> --- a/drivers/i2c/busses/i2c-at91-master.c
> +++ b/drivers/i2c/busses/i2c-at91-master.c
> @@ -831,7 +831,7 @@ static int at91_init_twi_recovery_gpio(struct platform_device *pdev,
>  	struct i2c_bus_recovery_info *rinfo = &dev->rinfo;
>  
>  	rinfo->pinctrl = devm_pinctrl_get(&pdev->dev);
> -	if (!rinfo->pinctrl || IS_ERR(rinfo->pinctrl)) {
> +	if (IS_ERR_OR_NULL(rinfo->pinctrl)) {
>  		dev_info(dev->dev, "can't get pinctrl, bus recovery not supported\n");
>  		return PTR_ERR(rinfo->pinctrl);
>  	}
> diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> index 10e89586ca72..8807c90df749 100644
> --- a/drivers/i2c/busses/i2c-imx.c
> +++ b/drivers/i2c/busses/i2c-imx.c
> @@ -1388,7 +1388,7 @@ static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
>  	struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
>  
>  	i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
> -	if (!i2c_imx->pinctrl || IS_ERR(i2c_imx->pinctrl)) {
> +	if (!IS_ERR_OR_NULL(i2c_imx->pinctrl)) {
>  		dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n");
>  		return PTR_ERR(i2c_imx->pinctrl);
>  	}

As stated in my previous reply to a similar patch, devm_pinctrl_get()
can not return NULL, so it makes more sense to remove the test for NULL
rather than "cleaning up" the buggy code, but leaving the bugs behind.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH -next] I2C: Use helper function IS_ERR_OR_NULL()

[Russell King (Oracle)]

On Wed, Aug 16, 2023 at 11:51:54AM +0200, Yann Sionneau wrote:
> Le 16/08/2023 à 11:46, Ruan Jinjie a écrit :
> 
> > Use IS_ERR_OR_NULL() instead of open-coding it
> > to simplify the code.
> >   	rinfo->pinctrl = devm_pinctrl_get(&pdev->dev);
> > -	if (!rinfo->pinctrl || IS_ERR(rinfo->pinctrl)) {
> > +	if (IS_ERR_OR_NULL(rinfo->pinctrl)) {
> 
> Can the return of devm_pinctrl_get really be NULL?

No.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH -next] I2C: Use helper function IS_ERR_OR_NULL()

[Ruan Jinjie]

On 2023/8/16 18:08, Russell King (Oracle) wrote:
> On Wed, Aug 16, 2023 at 05:48:34PM +0800, Ruan Jinjie wrote:
>>
>>
>> On 2023/8/16 17:46, Ruan Jinjie wrote:
>>> Use IS_ERR_OR_NULL() instead of open-coding it
>>> to simplify the code.
>>>
>>> Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
>>> ---
>>>  drivers/i2c/busses/i2c-at91-master.c | 2 +-
>>>  drivers/i2c/busses/i2c-imx.c         | 2 +-
>>>  2 files changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c
>>> index 94cff1cd527e..0e454c04a145 100644
>>> --- a/drivers/i2c/busses/i2c-at91-master.c
>>> +++ b/drivers/i2c/busses/i2c-at91-master.c
>>> @@ -831,7 +831,7 @@ static int at91_init_twi_recovery_gpio(struct platform_device *pdev,
>>>  	struct i2c_bus_recovery_info *rinfo = &dev->rinfo;
>>>  
>>>  	rinfo->pinctrl = devm_pinctrl_get(&pdev->dev);
>>> -	if (!rinfo->pinctrl || IS_ERR(rinfo->pinctrl)) {
>>> +	if (IS_ERR_OR_NULL(rinfo->pinctrl)) {
>>>  		dev_info(dev->dev, "can't get pinctrl, bus recovery not supported\n");
>>>  		return PTR_ERR(rinfo->pinctrl);
>>>  	}
>>> diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
>>> index 10e89586ca72..8807c90df749 100644
>>> --- a/drivers/i2c/busses/i2c-imx.c
>>> +++ b/drivers/i2c/busses/i2c-imx.c
>>> @@ -1388,7 +1388,7 @@ static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
>>>  	struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
>>>  
>>>  	i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
>>> -	if (!i2c_imx->pinctrl || IS_ERR(i2c_imx->pinctrl)) {
>>> +	if (!IS_ERR_OR_NULL(i2c_imx->pinctrl)) {
>>
>> Sorry, there is a problem, please ignore it.
> 
> I don't think these conversions are appropriate for devm_pinctrl_get().
> If one reads the code for devm_pinctrl_get() and pinctrl_get(), then
> one finds that it will never return NULL.

Right! devm_pinctrl_get() never return NULL.

> 
> So the tests for NULL do not serve any practical purpose than giving
> coders a warm fuzzy feeling that they've tested for a NULL pointer.
> Practically, they are of no use, so should be removed... thus making
> the conversion to IS_ERR_OR_NULL() irrelevant.
> 

Re: [PATCH -next] I2C: Use helper function IS_ERR_OR_NULL()

[Ruan Jinjie]

On 2023/8/16 18:22, Russell King (Oracle) wrote:
> On Wed, Aug 16, 2023 at 05:46:18PM +0800, Ruan Jinjie wrote:
>> Use IS_ERR_OR_NULL() instead of open-coding it
>> to simplify the code.
>>
>> Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
>> ---
>>  drivers/i2c/busses/i2c-at91-master.c | 2 +-
>>  drivers/i2c/busses/i2c-imx.c         | 2 +-
>>  2 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c
>> index 94cff1cd527e..0e454c04a145 100644
>> --- a/drivers/i2c/busses/i2c-at91-master.c
>> +++ b/drivers/i2c/busses/i2c-at91-master.c
>> @@ -831,7 +831,7 @@ static int at91_init_twi_recovery_gpio(struct platform_device *pdev,
>>  	struct i2c_bus_recovery_info *rinfo = &dev->rinfo;
>>  
>>  	rinfo->pinctrl = devm_pinctrl_get(&pdev->dev);
>> -	if (!rinfo->pinctrl || IS_ERR(rinfo->pinctrl)) {
>> +	if (IS_ERR_OR_NULL(rinfo->pinctrl)) {
>>  		dev_info(dev->dev, "can't get pinctrl, bus recovery not supported\n");
>>  		return PTR_ERR(rinfo->pinctrl);
>>  	}
>> diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
>> index 10e89586ca72..8807c90df749 100644
>> --- a/drivers/i2c/busses/i2c-imx.c
>> +++ b/drivers/i2c/busses/i2c-imx.c
>> @@ -1388,7 +1388,7 @@ static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
>>  	struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
>>  
>>  	i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
>> -	if (!i2c_imx->pinctrl || IS_ERR(i2c_imx->pinctrl)) {
>> +	if (!IS_ERR_OR_NULL(i2c_imx->pinctrl)) {
>>  		dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n");
>>  		return PTR_ERR(i2c_imx->pinctrl);
>>  	}
> 
> As stated in my previous reply to a similar patch, devm_pinctrl_get()
> can not return NULL, so it makes more sense to remove the test for NULL
> rather than "cleaning up" the buggy code, but leaving the bugs behind.

Right! I'll fix it sooner. Thank you very much.

>