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    SubjectRe: [PATCH v10 5/6] usb:cdns3 Add Cadence USB3 DRD Driver
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    On 12/08/2019 15:46, Felipe Balbi wrote:
    >
    > Hi,
    >
    > Roger Quadros <rogerq@ti.com> writes:
    >>> The sysfs file we expose from the class for the role switches is
    >>> primarily meant for supporting proprietary protocols that require us
    >>> to basically override the connector USB data role. The default role
    >>> should always be selected in the drivers.
    >>
    >> OK. Let's take this example
    >> - Port is dual-role port micro AB.
    >> - microAB to type-A adapter is connected which pulls ID low. port transitions
    >> to "host" role by the controller driver.
    >> - proprietary protocol want to switch role to device role so writes "device" to
    >> mode switch sysfs. port transitions to "device" role.
    >>
    >> Now, how does controller driver know to fall back to HW based role switching?
    >
    > Use a 'disconnect' or 'suspend' event to go reset it? But that should,
    > probably, be done at kernel space, no?
    >

    Yes that could be one option.
    So after a disconnect, sysfs role should reflect actual hardware role. correct?

    cheers,
    -roger
    --
    Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
    Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

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