[V4 PATCH 18/26] usb: phy: mv_usb2_phy: add externel chip support

[Chao Xie]

On Mon, Jan 21, 2013 at 11:51 PM, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Mon, Jan 21, 2013 at 05:07:36AM -0500, Chao Xie wrote:
>> +     mv_phy->extern_chip.head = devm_kzalloc(&pdev->dev,
>> +                                     sizeof(*mv_phy->extern_chip.head),
>> +                                     GFP_KERNEL);
>> +     if (mv_phy->extern_chip.head == NULL)
>> +             return -ENOMEM;
>> +     ATOMIC_INIT_NOTIFIER_HEAD(mv_phy->extern_chip.head);
>
> Why do you need to allocate an atomic notifier list head as an entirely
> separate data structure?
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Th reason is that the original code seperate the extern_chip and phy
support. So it depends
on the ->head to detect whether extern_chip is initialized or not.
Now it is combined with phy, the ->phy pointer can do the job.