Re: [patch v2 1/3] drivers: phy: Make NULL a valid phy reference

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

On 02/03/2014 09:13 PM, Andrew Lunn wrote:

>>> The common clock framework considers NULL a valid clock
>>> reference. This makes handling optional clocks simple, in that if the
>>> optional clock is not available, a NULL reference can be used in the
>>> place of a real clock, simplifying the clock consumer.

>>> Extend this concept to the phy consumer API. A NULL can be passed to
>>> the release calls, the phy_init() and phy_exit() calls, and
>>> phy_power_on() and phy_power_off() and a NOP is performed.

>>> Signed-off-by: Andrew Lunn <andrew@lunn.ch>
>> [...]

>>>   When the controller no longer needs the PHY, it has to release the reference
>>> diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
>>> index 645c867c1257..56535253e50c 100644
>>> --- a/drivers/phy/phy-core.c
>>> +++ b/drivers/phy/phy-core.c
>> [...]
>>> @@ -308,6 +320,9 @@ err0:
>>>    */
>>>   void phy_put(struct phy *phy)
>>>   {
>>> +	if (!phy)
>>> +		return;
>>> +
>>>   	if (IS_ERR(phy))
>>>   		return;

>>     Why not merge these two?

> Hi Sergei

> Have you heard Russell King talk about IS_ERR_NULL()?

    Probably not but I didn't think of it actually, just:

	if (!phy || IS_ERR(phy))
		return;

PS: BTW, I'm not sure why phy_put() has to handle error pointers...

>       Andrew

WBR, Sergei