Re: [PATCH v4 2/3] usb: phy: Add Qualcomm SS-USB and HS-USB drivers for DWC3 core

From: Kumar Gala
Date: Tue Aug 20 2013 - 11:01:12 EST



On Aug 20, 2013, at 9:54 AM, Ivan T. Ivanov wrote:

>
> Hi,
>
> On Tue, 2013-08-20 at 09:33 -0500, Felipe Balbi wrote:
>> On Tue, Aug 20, 2013 at 05:09:11PM +0300, Ivan T. Ivanov wrote:
>>> Hi,
>>>
>>> On Tue, 2013-08-20 at 08:37 -0500, Felipe Balbi wrote:
>>>> Hi,
>>>>
>>>> On Tue, Aug 20, 2013 at 04:32:23PM +0300, Ivan T. Ivanov wrote:
>>>>>> On Tue, Aug 20, 2013 at 12:56:04PM +0300, Ivan T. Ivanov wrote:
>>>>>>> From: "Ivan T. Ivanov" <iivanov@xxxxxxxxxx>
>>>>>>>
>>>>>>> These drivers handles control and configuration of the HS
>>>>>>> and SS USB PHY transceivers. They are part of the driver
>>>>>>> which manage Synopsys DesignWare USB3 controller stack
>>>>>>> inside Qualcomm SoC's.
>>>>>>>
>>>>>>> Signed-off-by: Ivan T. Ivanov <iivanov@xxxxxxxxxx>
>>>>>>> ---
>>>>>>> drivers/usb/phy/Kconfig | 11 ++
>>>>>>> drivers/usb/phy/Makefile | 2 +
>>>>>>> drivers/usb/phy/phy-msm-dwc3-hs.c | 327 ++++++++++++++++++++++++++++++++
>>>>>>> drivers/usb/phy/phy-msm-dwc3-ss.c | 374 +++++++++++++++++++++++++++++++++++++
>>>>>>
>>>>>> please rename these PHY drivers, they have nothing to do with DWC3. PHYs
>>>>>> don't care about the USB controller.
>>>>>
>>>>> I think they are SNPS DesignWare PHY's, additionally
>>>>> wrapped with Qualcomm logic. I could substitute "dwc3"
>>>>> with just "dw", which will be more correct.
>>>>
>>>> alright, thank you. Let's add Paul to the loop since he might have very
>>>> good insight in the synopsys PHYs.
>>>>
>>>> mental note: if any other platform shows up with Synopsys PHY, ask them
>>>> to use this driver instead :-)
>>>
>>> I really doubt that this will bi possible. Control of the PHY's is
>>> not directly trough ULPI, UTMI or PIPE3 interfaces, but trough
>>> QSCRATCH registers, which of course is highly Qualcomm specific.
>>
>> isn't it a memory mapped IP ? doesn't synopsys provide their own set of
>> registers ?
>
> From what I see it is not directly mapped. How QSCRATCH write and
> reads transactions are translated to DW IP is unclear to me.


I think the question is how does SW access them?

- k

--
Employee of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation

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