[PATCH 2/4] usb: host: xhci-plat: Add support to get PHYs

Vivek Gautam gautam.vivek at samsung.com
Tue Jun 24 22:49:55 PDT 2014


HI Sergei,


On Wed, Jun 25, 2014 at 4:04 AM, Sergei Shtylyov
<sergei.shtylyov at cogentembedded.com> wrote:
> Hello.
>
>
> On 06/10/2014 12:22 AM, Julius Werner wrote:
>
>>> diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
>>> index 9ffecd5..453d89e 100644
>>> --- a/drivers/usb/host/xhci.h
>>> +++ b/drivers/usb/host/xhci.h
>>> @@ -1582,6 +1582,9 @@ struct xhci_hcd {
>>>          u32                     port_status_u0;
>>>   /* Compliance Mode Timer Triggered every 2 seconds */
>>>   #define COMP_MODE_RCVRY_MSECS 2000
>>> +       /* phys for the controller */
>>> +       struct phy              *phy2_gen;
>>> +       struct phy              *phy3_gen;
>>>   };
>
>
>> I don't think adding new variables here and restricting most of this
>> logic to xhci-plat.c (in the next patch) is the best way to do it.
>
>
>    Indeed.
>
>
>> There's no conceptual reason why other host controllers (e.g. xhci-pci
>> or even EHCI) could not have a similar need to tune their PHY after
>> reset. PHYs are universal to all host controllers.
>
>
>> There is already a 'phy' member in struct usb_hcd which I think is
>> mostly unused right now. I think it would be much less
>> confusing/redundant to reuse that member for this purpose (you could
>> still set it up from xhci_plat_probe(), and then call it from
>> hcd_bus_resume() or something like that).
>
>
>    That member has type 'struct usb_phy *' while here we have 'struct phy *'
> -- feel the difference.
>    I have already tried adding 'struct phy *gen_phy' to 'struct usb_hcd',
> however Greg wasn't eager to pick that up so far. Here's the last posting of
> my patch:
>
> http://marc.info/?l=linux-usb&m=140145917506582

Thanks for pointing to the patch, i have also been tracking this patch.
I will try to rework using this patch and post the relevant patches.



-- 
Best Regards
Vivek Gautam
Samsung R&D Institute, Bangalore
India



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