Re: [RFC][PATCH 2/2] usb: dwc2: Add a quirk to allow speed negotiation for Hisilicon Hi6220

From: John Stultz
Date: Thu Oct 13 2016 - 19:52:00 EST


On Thu, Oct 13, 2016 at 4:29 PM, John Stultz <john.stultz@xxxxxxxxxx> wrote:
> From: Chen Yu <chenyu56@xxxxxxxxxx>
>
> The Hi6220's usb controller is limited in that it does not
> automatically autonegotiate the usb speed. Thus it requires a
> quirk so that we can manually negotiate the best usb speed for
> the attached device.
>
> Cc: Wei Xu <xuwei5@xxxxxxxxxxxxx>
> Cc: Guodong Xu <guodong.xu@xxxxxxxxxx>
> Cc: Amit Pundir <amit.pundir@xxxxxxxxxx>
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> Cc: Mark Rutland <mark.rutland@xxxxxxx>
> Cc: John Youn <johnyoun@xxxxxxxxxxxx>
> Cc: Douglas Anderson <dianders@xxxxxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: linux-usb@xxxxxxxxxxxxxxx
> Signed-off-by: Chen Yu <chenyu56@xxxxxxxxxx>
> Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
> ---
> arch/arm64/boot/dts/hisilicon/hi6220.dtsi | 1 +
> drivers/usb/dwc2/core.h | 7 +++
> drivers/usb/dwc2/hcd.c | 75 +++++++++++++++++++++++++++++++
> drivers/usb/dwc2/platform.c | 3 ++
> 4 files changed, 86 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/hisilicon/hi6220.dtsi b/arch/arm64/boot/dts/hisilicon/hi6220.dtsi
> index 17839db..2c8f435 100644
> --- a/arch/arm64/boot/dts/hisilicon/hi6220.dtsi
> +++ b/arch/arm64/boot/dts/hisilicon/hi6220.dtsi
> @@ -752,6 +752,7 @@
> g-np-tx-fifo-size = <128>;
> g-tx-fifo-size = <128 128 128 128 128 128>;
> interrupts = <0 77 0x4>;
> + hi6220,change_speed_quirk;


I also realize I'm missing the DT binding documentation for this, but
I wanted to get a rough idea if this approach was ok first.
On the next submission (if there aren't major objections to the
approach) I can split the binding documentation and dts change into
different patches.

thanks
-john