Re: [PATCH v3 15/16] usb: musb: da8xx: Use devm in probe

[Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>]

Hello.

On 4/1/2016 1:21 AM, Bin Liu wrote:

>> Simplify things a bit by using devm functions where possible.
>>
>> Signed-off-by: David Lechner <david@lechnology.com>
>> ---
>>
>> v3 changes:
>>
>> * Kept clk variable to minimize noise.
>>
>>
>>   drivers/usb/musb/da8xx.c | 19 +++++--------------
>>   1 file changed, 5 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/usb/musb/da8xx.c b/drivers/usb/musb/da8xx.c
>> index b03d3b8..0c1997c 100644
>> --- a/drivers/usb/musb/da8xx.c
>> +++ b/drivers/usb/musb/da8xx.c
>> @@ -490,20 +490,18 @@ static int da8xx_probe(struct platform_device *pdev)
>>   	struct da8xx_glue		*glue;
>>   	struct platform_device_info	pinfo;
>>   	struct clk			*clk;
>> +	int				ret;
>>
>> -	int				ret = -ENOMEM;
>> -
>> -	glue = kzalloc(sizeof(*glue), GFP_KERNEL);
>> +	glue = devm_kzalloc(&pdev->dev, sizeof(*glue), GFP_KERNEL);
>>   	if (!glue) {
>>   		dev_err(&pdev->dev, "failed to allocate glue context\n");
>> -		goto err0;
>> +		return -ENOMEM;
>>   	}
>>
>> -	clk = clk_get(&pdev->dev, "usb20");
>> +	clk = devm_clk_get(&pdev->dev, "usb20");
>>   	if (IS_ERR(clk)) {
>>   		dev_err(&pdev->dev, "failed to get clock\n");
>> -		ret = PTR_ERR(clk);
>> -		goto err3;
>> +		return PTR_ERR(clk);
>
> memory leak due to not kfree(glue).

    No, since devm_kzalloc() was used, the memory will be automatically freed 
on returning error by da8xx_probe().

>>   	}
>>
>>   	ret = clk_enable(clk);
>> @@ -560,12 +558,7 @@ err5:
>>   	clk_disable(clk);
>>
>>   err4:
>> -	clk_put(clk);
>> -
>> -err3:
>> -	kfree(glue);
>>
>> -err0:
>>   	return ret;
>>   }
>>
>> @@ -576,8 +569,6 @@ static int da8xx_remove(struct platform_device *pdev)
>>   	platform_device_unregister(glue->musb);
>>   	usb_phy_generic_unregister(glue->phy);
>>   	clk_disable(glue->clk);
>> -	clk_put(glue->clk);
>> -	kfree(glue);
>
> Doesn't match with $subject, I'd put them into a seperate patch.

    Again, these are now done automatically.

> Regards,
> -Bin.

MBR, Sergei