[PATCH v6 1/9] drivers: phy: add generic PHY framework
Kishon Vijay Abraham I
kishon at ti.com
Wed Jun 5 01:25:58 EDT 2013
On Tuesday 04 June 2013 07:13 PM, Sylwester Nawrocki wrote:
> On 06/04/2013 02:26 PM, Kishon Vijay Abraham I wrote:
>>>> +static inline int phy_init(struct phy *phy)
>>>> + pm_runtime_get_sync(&phy->dev);
>>> Hmm, no need to check return value here ? Also it looks a bit unexpected to
>> I purposely dint check the return values in order to support platforms
>> that don’t enable pm_runtime.
> Then I guess this should be called conditionally and any errors returned
> if runtime PM is enabled ? Not sure if pm_runtime_enabled() would be
> helpful such situation.
Indeed. I think it can be used.
>>> possibly have runtime_resume callback of a PHY device called before ops->init()
>>> call ? It seems a bit unclear what the purpose of init() callback is.
>> Not really. Anything that is used to initialize the PHY (internal
>> configuration) can go in phy_init. Usually in runtime_resume callback,
>> optional functional clocks are enabled and also in some cases context
>> restore is done. So it really makes sense to enable clocks/module
>> (pm_runtime_get_sync) before doing a PHY configuration (phy_init).
> OK, that makes sense. All PHY device resources must be prepared anyway
> before a PHY object is registered with the PHY core.
>>>> + if (phy->ops->init)
>>>> + return phy->ops->init(phy);
>>>> + return -EINVAL;
>>>> +static inline int phy_exit(struct phy *phy)
>>>> + int ret = -EINVAL;
>>>> + if (phy->ops->exit)
>>>> + ret = phy->ops->exit(phy);
>>>> + pm_runtime_put_sync(&phy->dev);
>>>> + return ret;
>>> Do phy_init/phy_exit need to be mandatory ? What if there is really
>> No. phy_init/phy_exit is not mandatory at all.
>>> nothing to do in those callbacks ? Perhaps -ENOIOCTLCMD should be
>>> returned if a callback is not implemented, so PHY users can recognize
>>> such situation and proceed ?
>> So currently these APIs return -EINVAL if these callbacks are not
>> populated which is good enough IMHO.
> But -EINVAL could be well returned from the callback function. Perhaps
> ENOTSUPP could be used instead ?
hmm.. could be..
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