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    SubjectRe: [RFC 11/19] dwc3: add OTG handling code
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    Hi Robert,


    On Wed, Mar 18, 2015 at 7:34 PM, Robert Baldyga <r.baldyga@samsung.com> wrote:
    >
    > This patch introduces OTG support in DWC3 driver. OTG feature is responsible
    > for dynamic USB role switching (between host and peripheral modes) based
    > on detected cable type.
    >
    > Each role switch causes complete core reinitialization. In peripheral

    Do you really want to do complete core reinitialization?
    While switching to HOST mode you might need to issue a LHRESET and
    while switching
    to Device mode make sure you re-initiallize the event buffer addresses.

    If LHRESET is not used then you should do what you have done.

    But I don't think adding and removing the platform_device for XHCI is
    the way to go.
    This might impact SoC's which really implement the OTG for DWC3.

    I made an attempt on the same and could'nt work on it more.
    This still has some issues, but could be fixed.
    https://lkml.org/lkml/2014/11/25/600

    > mode UDC device is activated using VBUS session control mechanism. In
    > host mode the new XHCI device is registered to make bus visible in system.
    >
    > This code is inspired by DWC3 driver from Hardkernel Linux sources [1].
    >
    > [1] https://github.com/hardkernel/linux.
    >
    > Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>

    Regards
    -George


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