Re: [PATCH RFC 1/4] phy: Add new Exynos5 USB 3.0 PHY driver

From: Jingoo Han
Date: Tue Nov 05 2013 - 06:13:02 EST


On Tuesday, November 05, 2013 6:37 PM, Kamil Debski wrote:
> On Tuesday, November 05, 2013 8:20 AM, Vivek Gautam wrote:
> > On Mon, Nov 4, 2013 at 6:42 PM, Kishon Vijay Abraham I <kishon@xxxxxx> wrote:
> > > On Monday 04 November 2013 03:45 PM, Kamil Debski wrote:
> > >> On Monday, November 04, 2013 7:55 AM, Kishon Vijay Abraham I wrote:
> > >>> On Thursday 31 October 2013 01:15 PM, Vivek Gautam wrote:
> > >>>>
> > >>>> Add a new driver for the USB 3.0 PHY on Exynos5 series of SoCs.
> > >>>> The new driver uses the generic PHY framework and will interact
> > >>>> with
> > >>>> DWC3 controller present on Exynos5 series of SoCs.
> > >>>
> > >>>
> > >>> In Exynos, you have a single IP that supports both USB3 and USB2
> > PHY
> > >>> right? I think that needs to be mentioned here.
> > >>
> > >>
> > >> As far as I know the IP is different.
> > >
> > >
> > > Ok. Sometime back Vivek was mentioning about a single IP for both
> > USB3
> > > and USB2. Thought it should be this driver. Anyway thanks for the
> > clarification.
> >
> > Right Kishon, I had mentioned that Exynos5's dwc3 controller have a
> > single IP for USB2 and USB3 phy.
> > From what i see, on exynos5 systems the dwc3 controller uses a combo of
> > usb 2 (utmi+) and usb 3 (pipe 3) phy (with base address starting
> > 0x12100000).
> >
> > Kamil, Tomasz,
> >
> > Please correct me if i am wrong.
>
> I have the Exynos 5250 documentation and I found two phy register ranges:
> 1) USB 2.0 PHY having the base address of 0x1213 0000
> Chapter 33. USB 2.0 Host Controller
> Subchapter 33.5.2 Phy Control Register p. 1696
> First register's description is
> "USB2.0 phy control register"
> 2) USB 3.0 PHY (I guess) with the base address 0x1210 0000
> Chapter 35. USB 3.0 DRD Controller
> Subchapter 35.4.6 PHY Control Register p. 1872
>
> Jingoo, could you comment on the above? You may know more than we do :)

Hi Kamil,

Thank you for trusting me. :-)
I just asked my validation engineer about 5250 USB PHY.
As I know, she has the best knowledge about Samsung SoC USB hardware.
She said that there are 2 PHY controllers such as USB 2.0 PHY, USB 3.0 PHY.

1) USB2.0 PHY: USB2.0 HOST, USB2.0 Device
2) USB3.0 PHY: USB3.0 DRD (3.0 HOST & 3.0 Device)

> In addition, I have a question to you Vivek - does your USB 3.0
> PHY support both host and device?

According to her, USB3.0 PHY can support both 3.0 Host and 3.0 Device.
Thank you.

Best regards,
Jingoo Han

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