Subject: Re: [PATCH v3] stmmac: fix check for phydev being open

From: Sergei Shtylyov <[email-masked]>
Date: Tue, 8 Sep 2015 22:53:51 +0300

Hello.

On 09/08/2015 03:46 PM, Alexey Brodkin wrote:

>>> Current check of phydev with IS_ERR(phydev) may make not much sense
>>> because of_phy_connect() returns NULL on failure instead of error value.
>>>
>>> Still for checking result of phy_connect() IS_ERR() makes perfect sense.
>>>
>>> So let's use combined check IS_ERR_OR_NULL() that covers both cases.
>>>
>>> Cc: Sergei Shtylyov <[email-masked]>
>>> Cc: Giuseppe Cavallaro <[email-masked]>
>>> Cc: [email-masked]
>>> Cc: [email-masked]
>>> Cc: David Miller <[email-masked]>
>>> Signed-off-by: Alexey Brodkin <[email-masked]>
>>> ---
>>>
>>> Changes compared to v2:
>>>    * Updated commit message with mention of of_phy_connect() instead of
>>>      of_phy_attach().
>>>    * Return ENODEV in case of of_phy_connect() failure
>>>
>>> Changes compared to v1:
>>>    * Use IS_ERR_OR_NULL() instead of discrete checks for null and err
>>>
>>>    drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 7 +++++--
>>>    1 file changed, 5 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>>> index 864b476..e2c9c86 100644
>>> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>>> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>>> @@ -837,9 +837,12 @@ static int stmmac_init_phy(struct net_device *dev)
>>>    				     interface);
>>>    	}
>>>
>>> -	if (IS_ERR(phydev)) {
>>> +	if (IS_ERR_OR_NULL(phydev)) {
>>>    		pr_err("%s: Could not attach to PHY\n", dev->name);
>>> -		return PTR_ERR(phydev);
>>> +		if (!phydev)
>>> +			return -ENODEV;
>>> +		else
>>> +			return PTR_ERR(phydev);
>>
>>      Don't need *else* after *return* and scripts/checkpatch.pl should have
>> complained about that.
>
> ./scripts/checkpatch.pl 0001-stmmac-fix-check-for-phydev-being-open.patch
> total: 0 errors, 0 warnings, 0 checks, 14 lines checked

    Hm... I bet I saw such warning from checkpatch.pl recently (it was a false 
positive though, so maybe the check was removed recently, not sure). Your 
patch is clean indeed, however my comment is still valid.

> -Alexey

MBR, Sergei