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    SubjectRE: [PATCH v12 7/8] usb: Adding SuperSpeed support to dummy_hcd
    > > > > +
    > > > > +static struct dummy_hcd_module_parameters mod_data = {
    > > > > + .is_super_speed = false
    > > > > +};
    > > > > +module_param_named(is_super_speed, mod_data.is_super_speed,
    > bool,
    > > > > +S_IRUGO); MODULE_PARM_DESC(is_super_speed, "true to simulate
    > > > > +SuperSpeed connection");
    > > >
    > > > you shouldn't need this. You should always enable SuperSpeed for
    > > > this driver.
    > >
    > > You mean I don't need the module parameter? IMO it's the best way to
    > > enable HS connection. If driver->speed=USB_SPEED_SUPER than dummy_hcd
    > > will try to enumerate the device on the SS root hub and if the gadget
    > > didn't provide SS descriptors - it will fail. Just as it happened
    > > before. Finding out from
    > then it should hand the device over to the hs_hcd ;-) Meaning it would
    > disconnect the device, switch to hs_hcd and reconnect :-)

    Yes this will be the best solution :) But as I said, the enumeration occurs
    not in dummy_hcd thus I'm not sure how dummy_hcd can find out that it failed
    in order to reconnect the device to hs_hcd. And I'm not sure that dummy_hcd
    should care whether the enumeration succeeds or fails. It seems to me that
    this should be handled by upper levels. Shouldn't it?
    But we're discussing a more general issue; do you remember what the usb30
    spec sais about this? I mean when connecting a HS device to a SS port (over
    SS cable), should it still enumerate as a HS device? It seems to me that the
    answer is no but I'm not sure...

    > > dummy_hcd that the enumeration failed is very complicated (if even
    > > possible) and I'm not sure that is the right thing to do... If you
    > > connect a real device over SS port to xHCI and the device doesn't
    > > provide SS descriptors - the enumeration fails and it's ok. But if
    > you
    > > connect the same device to a HS port - it should work properly. This
    > > is what I tried to simulate with this parameter.
    > it doesn't just fails, it gives the device over to the shared_hcd :-)

    Hmmm.... I have v2.6.38 installed on my Linux-host at the moment and I just
    verified that when connecting a Gadget driver without SS descriptors over SS
    connection - the enumeration fails. Was this fixed in v2.6.39? It will take
    me some time to upgrade to v2.6.39 and verify but I have to do it any way
    so I'll give it a shot...

    Best regards,
    Tanya Brokhman
    Consultant for Qualcomm Innovation Center, Inc.
    Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum

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      Last update: 2011-05-23 10:19    [W:0.021 / U:9.016 seconds]
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