[V8 PATCH 01/16] usb: phy: mv_usb2: add PHY driver for marvell usb2 controller

Chao Xie xiechao.mail at gmail.com
Wed Mar 6 03:24:58 EST 2013


On Wed, Mar 6, 2013 at 4:10 PM, Felipe Balbi <balbi at ti.com> wrote:
> Hi,
>
> On Wed, Mar 06, 2013 at 10:11:41AM +0800, Chao Xie wrote:
>> 3. For the revison register. It exists in some SOCes(pxa168), but for
>> some SOCes, the register dispears(pxa910, armada610). These SOCes are
>> developed by different desgin teams, and it need to be enhanced, but
>> for current products i have to use the device_id to detect the PHY
>> controller.
>
> fair enough, make sure to add a comment to the driver about this so
> grumpy maintainers stop complaining ;-)
>
>> 4. For the mutex and refcount. The "USB controller" includes two
>> blocks - the udc and ehci. In fact they will not be used at same time,
>> but for some SOCes it duplicates the ehci block. It means that the
>> SOCes have two or more ehci blocks. The added ehci blocks depend on
>> the PHY to be initialized, and they can be used at same time as the
>> "USB controller". That is the reason i add mutex and refcount for phy
>> driver.
>
> alright, let's add refcounting to the generic PHY layer then.
>
>> 5. For the clock name. Can you describe it in details? For clkdev, if
>> it want to find the clock, it still depends on the dev_name and
>> con_id.
>
> right, the idea of clkdev is that you associate a clock provider with
> its consumer by means of dev_name. Then you can fetch the clock from
> driver with any name you want. Which means if you do you clkdev properly
> you could:
>
> clk_get(dev, "clk1");
> clk_get(dev, "clk2");
> ...
>
> and so on.
>

It is same as what i think.
The clock numbers and names are depent of SOCes, i do not want to fix
it in ther driver. So i use pdata to pass the clknum and clk names
"clk1", "clk2" and so on.
in the driver, i use
devm_clk_get(&pdev->dev, pdata->clkname[i]);
Do you think it is acceptable?

When device tree for clock framework are supported, the things get
easier, and it is my next step.

> good luck
>
> --
> balbi



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