[PATCH] usb: bdc: Remove duplicate error message in bdc_probe()

[PATCH] usb: bdc: Remove duplicate error message in bdc_probe()

[Tang Bin]

In this function, we don't need dev_err() message because
when something goes wrong, devm_platform_ioremap_resource()
can print an error message itself, so remove the redundant
one.

Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
---
 drivers/usb/gadget/udc/bdc/bdc_core.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/usb/gadget/udc/bdc/bdc_core.c b/drivers/usb/gadget/udc/bdc/bdc_core.c
index 02a3a7746..9454f179e 100644
--- a/drivers/usb/gadget/udc/bdc/bdc_core.c
+++ b/drivers/usb/gadget/udc/bdc/bdc_core.c
@@ -508,10 +508,8 @@ static int bdc_probe(struct platform_device *pdev)
 	bdc->clk = clk;
 
 	bdc->regs = devm_platform_ioremap_resource(pdev, 0);
-	if (IS_ERR(bdc->regs)) {
-		dev_err(dev, "ioremap error\n");
+	if (IS_ERR(bdc->regs))
 		return -ENOMEM;
-	}
 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0)
 		return irq;
-- 
2.20.1.windows.1

Re: [PATCH] usb: bdc: Remove duplicate error message in bdc_probe()

[Greg KH]

On Sun, Sep 27, 2020 at 09:42:18PM +0800, Tang Bin wrote:
> In this function, we don't need dev_err() message because
> when something goes wrong, devm_platform_ioremap_resource()
> can print an error message itself, so remove the redundant
> one.
> 
> Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
> Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
> ---
>  drivers/usb/gadget/udc/bdc/bdc_core.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/gadget/udc/bdc/bdc_core.c b/drivers/usb/gadget/udc/bdc/bdc_core.c
> index 02a3a7746..9454f179e 100644
> --- a/drivers/usb/gadget/udc/bdc/bdc_core.c
> +++ b/drivers/usb/gadget/udc/bdc/bdc_core.c
> @@ -508,10 +508,8 @@ static int bdc_probe(struct platform_device *pdev)
>  	bdc->clk = clk;
>  
>  	bdc->regs = devm_platform_ioremap_resource(pdev, 0);
> -	if (IS_ERR(bdc->regs)) {
> -		dev_err(dev, "ioremap error\n");
> +	if (IS_ERR(bdc->regs))
>  		return -ENOMEM;

Why not return the error given to us?

thanks,

greg k-h

Re: [PATCH] usb: bdc: Remove duplicate error message in bdc_probe()

[Chunfeng Yun]

On Sun, 2020-09-27 at 21:42 +0800, Tang Bin wrote:
> In this function, we don't need dev_err() message because
> when something goes wrong, devm_platform_ioremap_resource()
> can print an error message itself, so remove the redundant
> one.
> 
> Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
> Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
> ---
>  drivers/usb/gadget/udc/bdc/bdc_core.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/gadget/udc/bdc/bdc_core.c b/drivers/usb/gadget/udc/bdc/bdc_core.c
> index 02a3a7746..9454f179e 100644
> --- a/drivers/usb/gadget/udc/bdc/bdc_core.c
> +++ b/drivers/usb/gadget/udc/bdc/bdc_core.c
> @@ -508,10 +508,8 @@ static int bdc_probe(struct platform_device *pdev)
>  	bdc->clk = clk;
>  
>  	bdc->regs = devm_platform_ioremap_resource(pdev, 0);
> -	if (IS_ERR(bdc->regs)) {
> -		dev_err(dev, "ioremap error\n");
> +	if (IS_ERR(bdc->regs))
>  		return -ENOMEM;
> -	}
>  	irq = platform_get_irq(pdev, 0);
>  	if (irq < 0)
>  		return irq;

Cc bdc's maintainer:  Florian Fainelli <f.fainelli@gmail.com>

Re: [PATCH] usb: bdc: Remove duplicate error message in bdc_probe()

[Tang Bin]

在 2020/9/28 14:49, Chunfeng Yun 写道:
> On Sun, 2020-09-27 at 21:42 +0800, Tang Bin wrote:
>> In this function, we don't need dev_err() message because
>> when something goes wrong, devm_platform_ioremap_resource()
>> can print an error message itself, so remove the redundant
>> one.
>>
>> Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
>> Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
>> ---
>>   drivers/usb/gadget/udc/bdc/bdc_core.c | 4 +---
>>   1 file changed, 1 insertion(+), 3 deletions(-)
>>
>> diff --git a/drivers/usb/gadget/udc/bdc/bdc_core.c b/drivers/usb/gadget/udc/bdc/bdc_core.c
>> index 02a3a7746..9454f179e 100644
>> --- a/drivers/usb/gadget/udc/bdc/bdc_core.c
>> +++ b/drivers/usb/gadget/udc/bdc/bdc_core.c
>> @@ -508,10 +508,8 @@ static int bdc_probe(struct platform_device *pdev)
>>   	bdc->clk = clk;
>>   
>>   	bdc->regs = devm_platform_ioremap_resource(pdev, 0);
>> -	if (IS_ERR(bdc->regs)) {
>> -		dev_err(dev, "ioremap error\n");
>> +	if (IS_ERR(bdc->regs))
>>   		return -ENOMEM;
>> -	}
>>   	irq = platform_get_irq(pdev, 0);
>>   	if (irq < 0)
>>   		return irq;
> Cc bdc's maintainer:  Florian Fainelli <f.fainelli@gmail.com>

Got it, thanks.

Tang Bin

>
>

Re: [PATCH] usb: bdc: Remove duplicate error message in bdc_probe()

[Tang Bin]

Hi Greg KH:

在 2020/9/27 21:45, Greg KH 写道:
> On Sun, Sep 27, 2020 at 09:42:18PM +0800, Tang Bin wrote:
>> In this function, we don't need dev_err() message because
>> when something goes wrong, devm_platform_ioremap_resource()
>> can print an error message itself, so remove the redundant
>> one.
>>
>> Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
>> Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
>> ---
>>   drivers/usb/gadget/udc/bdc/bdc_core.c | 4 +---
>>   1 file changed, 1 insertion(+), 3 deletions(-)
>>
>> diff --git a/drivers/usb/gadget/udc/bdc/bdc_core.c b/drivers/usb/gadget/udc/bdc/bdc_core.c
>> index 02a3a7746..9454f179e 100644
>> --- a/drivers/usb/gadget/udc/bdc/bdc_core.c
>> +++ b/drivers/usb/gadget/udc/bdc/bdc_core.c
>> @@ -508,10 +508,8 @@ static int bdc_probe(struct platform_device *pdev)
>>   	bdc->clk = clk;
>>   
>>   	bdc->regs = devm_platform_ioremap_resource(pdev, 0);
>> -	if (IS_ERR(bdc->regs)) {
>> -		dev_err(dev, "ioremap error\n");
>> +	if (IS_ERR(bdc->regs))
>>   		return -ENOMEM;
> Why not return the error given to us?

Because when get ioremap failed, devm_platform_ioremap_resource() can 
print error message

"dev_err(dev, "ioremap failed for resource %pR\n", res)" in it's called 
function. So I think this's place's

dev_err(dev, "ioremap error\n") is redundant.


Thanks

Tang Bin


>

Re: [PATCH] usb: bdc: Remove duplicate error message in bdc_probe()

[Felipe Balbi]

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Hi,

Tang Bin <tangbin@cmss.chinamobile.com> writes:
> Hi Greg KH:
>
> 在 2020/9/27 21:45, Greg KH 写道:
>> On Sun, Sep 27, 2020 at 09:42:18PM +0800, Tang Bin wrote:
>>> In this function, we don't need dev_err() message because
>>> when something goes wrong, devm_platform_ioremap_resource()
>>> can print an error message itself, so remove the redundant
>>> one.
>>>
>>> Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
>>> Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
>>> ---
>>>   drivers/usb/gadget/udc/bdc/bdc_core.c | 4 +---
>>>   1 file changed, 1 insertion(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/usb/gadget/udc/bdc/bdc_core.c b/drivers/usb/gadget/udc/bdc/bdc_core.c
>>> index 02a3a7746..9454f179e 100644
>>> --- a/drivers/usb/gadget/udc/bdc/bdc_core.c
>>> +++ b/drivers/usb/gadget/udc/bdc/bdc_core.c
>>> @@ -508,10 +508,8 @@ static int bdc_probe(struct platform_device *pdev)
>>>   	bdc->clk = clk;
>>>   
>>>   	bdc->regs = devm_platform_ioremap_resource(pdev, 0);
>>> -	if (IS_ERR(bdc->regs)) {
>>> -		dev_err(dev, "ioremap error\n");
>>> +	if (IS_ERR(bdc->regs))
>>>   		return -ENOMEM;
>> Why not return the error given to us?
>
> Because when get ioremap failed, devm_platform_ioremap_resource() can 
> print error message
>
> "dev_err(dev, "ioremap failed for resource %pR\n", res)" in it's called 
> function. So I think this's place's
>
> dev_err(dev, "ioremap error\n") is redundant.

that's not what Greg point you at, though. Greg's concern is valid in
that instead of passing along the error within bdc->regs, you always
return -ENOMEM. OTW, your code should read like so:

	if (IS_ERR(bdc->regs))
        	return PTR_ERR(bdc->regs);

-- 
balbi

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Re: [PATCH] usb: bdc: Remove duplicate error message in bdc_probe()

[Tang Bin]

Hi Balbi：

在 2020/9/28 17:40, Felipe Balbi 写道:
> Hi,
>
> Tang Bin <tangbin@cmss.chinamobile.com> writes:
>> Hi Greg KH:
>>
>> 在 2020/9/27 21:45, Greg KH 写道:
>>> On Sun, Sep 27, 2020 at 09:42:18PM +0800, Tang Bin wrote:
>>>> In this function, we don't need dev_err() message because
>>>> when something goes wrong, devm_platform_ioremap_resource()
>>>> can print an error message itself, so remove the redundant
>>>> one.
>>>>
>>>> Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
>>>> Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
>>>> ---
>>>>    drivers/usb/gadget/udc/bdc/bdc_core.c | 4 +---
>>>>    1 file changed, 1 insertion(+), 3 deletions(-)
>>>>
>>>> diff --git a/drivers/usb/gadget/udc/bdc/bdc_core.c b/drivers/usb/gadget/udc/bdc/bdc_core.c
>>>> index 02a3a7746..9454f179e 100644
>>>> --- a/drivers/usb/gadget/udc/bdc/bdc_core.c
>>>> +++ b/drivers/usb/gadget/udc/bdc/bdc_core.c
>>>> @@ -508,10 +508,8 @@ static int bdc_probe(struct platform_device *pdev)
>>>>    	bdc->clk = clk;
>>>>    
>>>>    	bdc->regs = devm_platform_ioremap_resource(pdev, 0);
>>>> -	if (IS_ERR(bdc->regs)) {
>>>> -		dev_err(dev, "ioremap error\n");
>>>> +	if (IS_ERR(bdc->regs))
>>>>    		return -ENOMEM;
>>> Why not return the error given to us?
>> Because when get ioremap failed, devm_platform_ioremap_resource() can
>> print error message
>>
>> "dev_err(dev, "ioremap failed for resource %pR\n", res)" in it's called
>> function. So I think this's place's
>>
>> dev_err(dev, "ioremap error\n") is redundant.
> that's not what Greg point you at, though. Greg's concern is valid in
> that instead of passing along the error within bdc->regs, you always
> return -ENOMEM. OTW, your code should read like so:
>
> 	if (IS_ERR(bdc->regs))
>          	return PTR_ERR(bdc->regs);

Thanks for your explain，when I send the patch yesterday, my point is at 
dev_err(), and not aimed at IS_ERR() & PTR_ERR(),

if it's Greg's point, I will change this patch after his reply.


Thank you very much.

Tang Bin

Re: [PATCH] usb: bdc: Remove duplicate error message in bdc_probe()

[Greg KH]

On Mon, Sep 28, 2020 at 06:55:26PM +0800, Tang Bin wrote:
> Hi Balbi：
> 
> 在 2020/9/28 17:40, Felipe Balbi 写道:
> > Hi,
> > 
> > Tang Bin <tangbin@cmss.chinamobile.com> writes:
> > > Hi Greg KH:
> > > 
> > > 在 2020/9/27 21:45, Greg KH 写道:
> > > > On Sun, Sep 27, 2020 at 09:42:18PM +0800, Tang Bin wrote:
> > > > > In this function, we don't need dev_err() message because
> > > > > when something goes wrong, devm_platform_ioremap_resource()
> > > > > can print an error message itself, so remove the redundant
> > > > > one.
> > > > > 
> > > > > Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
> > > > > Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
> > > > > ---
> > > > >    drivers/usb/gadget/udc/bdc/bdc_core.c | 4 +---
> > > > >    1 file changed, 1 insertion(+), 3 deletions(-)
> > > > > 
> > > > > diff --git a/drivers/usb/gadget/udc/bdc/bdc_core.c b/drivers/usb/gadget/udc/bdc/bdc_core.c
> > > > > index 02a3a7746..9454f179e 100644
> > > > > --- a/drivers/usb/gadget/udc/bdc/bdc_core.c
> > > > > +++ b/drivers/usb/gadget/udc/bdc/bdc_core.c
> > > > > @@ -508,10 +508,8 @@ static int bdc_probe(struct platform_device *pdev)
> > > > >    	bdc->clk = clk;
> > > > >    	bdc->regs = devm_platform_ioremap_resource(pdev, 0);
> > > > > -	if (IS_ERR(bdc->regs)) {
> > > > > -		dev_err(dev, "ioremap error\n");
> > > > > +	if (IS_ERR(bdc->regs))
> > > > >    		return -ENOMEM;
> > > > Why not return the error given to us?
> > > Because when get ioremap failed, devm_platform_ioremap_resource() can
> > > print error message
> > > 
> > > "dev_err(dev, "ioremap failed for resource %pR\n", res)" in it's called
> > > function. So I think this's place's
> > > 
> > > dev_err(dev, "ioremap error\n") is redundant.
> > that's not what Greg point you at, though. Greg's concern is valid in
> > that instead of passing along the error within bdc->regs, you always
> > return -ENOMEM. OTW, your code should read like so:
> > 
> > 	if (IS_ERR(bdc->regs))
> >          	return PTR_ERR(bdc->regs);
> 
> Thanks for your explain，when I send the patch yesterday, my point is at
> dev_err(), and not aimed at IS_ERR() & PTR_ERR(),
> 
> if it's Greg's point, I will change this patch after his reply.

Felipe is correct, and also, you should listen to him over me as he is
the maintainer of this part of the kernel :)

greg k-h

Re: [PATCH] usb: bdc: Remove duplicate error message in bdc_probe()

[Tang Bin]

Hi

在 2020/9/28 19:23, Greg KH 写道:
> On Mon, Sep 28, 2020 at 06:55:26PM +0800, Tang Bin wrote:
>> Hi Balbi：
>>
>> 在 2020/9/28 17:40, Felipe Balbi 写道:
>>> Hi,
>>>
>>> Tang Bin <tangbin@cmss.chinamobile.com> writes:
>>>> Hi Greg KH:
>>>>
>>>> 在 2020/9/27 21:45, Greg KH 写道:
>>>>> On Sun, Sep 27, 2020 at 09:42:18PM +0800, Tang Bin wrote:
>>>>>> In this function, we don't need dev_err() message because
>>>>>> when something goes wrong, devm_platform_ioremap_resource()
>>>>>> can print an error message itself, so remove the redundant
>>>>>> one.
>>>>>>
>>>>>> Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
>>>>>> Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
>>>>>> ---
>>>>>>     drivers/usb/gadget/udc/bdc/bdc_core.c | 4 +---
>>>>>>     1 file changed, 1 insertion(+), 3 deletions(-)
>>>>>>
>>>>>> diff --git a/drivers/usb/gadget/udc/bdc/bdc_core.c b/drivers/usb/gadget/udc/bdc/bdc_core.c
>>>>>> index 02a3a7746..9454f179e 100644
>>>>>> --- a/drivers/usb/gadget/udc/bdc/bdc_core.c
>>>>>> +++ b/drivers/usb/gadget/udc/bdc/bdc_core.c
>>>>>> @@ -508,10 +508,8 @@ static int bdc_probe(struct platform_device *pdev)
>>>>>>     	bdc->clk = clk;
>>>>>>     	bdc->regs = devm_platform_ioremap_resource(pdev, 0);
>>>>>> -	if (IS_ERR(bdc->regs)) {
>>>>>> -		dev_err(dev, "ioremap error\n");
>>>>>> +	if (IS_ERR(bdc->regs))
>>>>>>     		return -ENOMEM;
>>>>> Why not return the error given to us?
>>>> Because when get ioremap failed, devm_platform_ioremap_resource() can
>>>> print error message
>>>>
>>>> "dev_err(dev, "ioremap failed for resource %pR\n", res)" in it's called
>>>> function. So I think this's place's
>>>>
>>>> dev_err(dev, "ioremap error\n") is redundant.
>>> that's not what Greg point you at, though. Greg's concern is valid in
>>> that instead of passing along the error within bdc->regs, you always
>>> return -ENOMEM. OTW, your code should read like so:
>>>
>>> 	if (IS_ERR(bdc->regs))
>>>           	return PTR_ERR(bdc->regs);
>> Thanks for your explain，when I send the patch yesterday, my point is at
>> dev_err(), and not aimed at IS_ERR() & PTR_ERR(),
>>
>> if it's Greg's point, I will change this patch after his reply.
> Felipe is correct, and also, you should listen to him over me as he is
> the maintainer of this part of the kernel :)
>
Thanks for your reply, I will send v2 for all of you.


For me, all of you are the teachers, I am glad to learn from you. I 
respect every teacher,

I think Felipe should be able to feel.  Because the premise of the patch,

Felipe is also teaching me the question. So I feel I am lucky.


Thanks for all of you. Thanks

Tang Bin