Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <cd5455e9-b9ea-9376-1440-3dbf790d4c24@kernel.org>
Date:   Wed, 28 Sep 2022 09:49:11 +0300
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101
 Thunderbird/91.9.1
Subject: Re: [PATCH] usb: cdns3: remove dead code
Content-Language: en-US
To:     Pawel Laszczak <pawell@cadence.com>,
        Dongliang Mu <dzm91@hust.edu.cn>,
        Peter Chen <peter.chen@kernel.org>,
        Aswath Govindraju <a-govindraju@ti.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Dongliang Mu <mudongliangabcd@gmail.com>,
        "linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
References: <20220926135922.24541-1-dzm91@hust.edu.cn>
 <BYAPR07MB5381FCC10ABD4F92E47CF6D9DD549@BYAPR07MB5381.namprd07.prod.outlook.com>
From:   Roger Quadros <rogerq@kernel.org>
In-Reply-To: <BYAPR07MB5381FCC10ABD4F92E47CF6D9DD549@BYAPR07MB5381.namprd07.prod.outlook.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: bulk

Hello Pawel,

On 28/09/2022 09:40, Pawel Laszczak wrote:
>>
>> From: Dongliang Mu <mudongliangabcd@gmail.com>
>>
>> Smatch reports the following error:
>>
>> drivers/usb/cdns3/cdns3-plat.c:113 cdns3_plat_probe() warn:
>> platform_get_irq() does not return zero
>>
>>From the document, platform_get_irq_byname_optional only returns
>> non-zero value, and negative value on failure.
>>
>> Fix this by removing the zero value checking.
>>
>> Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
>> ---
>> drivers/usb/cdns3/cdns3-plat.c | 2 --
>> 1 file changed, 2 deletions(-)
>>
>> diff --git a/drivers/usb/cdns3/cdns3-plat.c b/drivers/usb/cdns3/cdns3-plat.c
>> index dc068e940ed5..2bc5d094548b 100644
>> --- a/drivers/usb/cdns3/cdns3-plat.c
>> +++ b/drivers/usb/cdns3/cdns3-plat.c
>> @@ -110,8 +110,6 @@ static int cdns3_plat_probe(struct platform_device *pdev)
>> 	cdns->wakeup_irq = platform_get_irq_byname_optional(pdev, "wakeup");
>> 	if (cdns->wakeup_irq == -EPROBE_DEFER)
>> 		return cdns->wakeup_irq;
>> -	else if (cdns->wakeup_irq == 0)
>> -		return -EINVAL;
>>
> I think that here we should have:
> 	else if (cdns->wakeup_irq == -ENXIO)
> 		return -EINVAL;
>  because of function: 
> platform_get_irq_byname_optional -> __platform_get_irq_byname returns
> irq number (>0),  -EPROBE_DEFFER or -ENXIO

But this is changing functionality and should come as a new patch.

The original patch is correct as it doesn't change existing code
functionality.

> 
> 
> thanks
> Pawel
> 
>> 	if (cdns->wakeup_irq < 0) {
>> 		dev_dbg(dev, "couldn't get wakeup irq\n");
>> --
>> 2.35.1
> 

cheers,
-roger