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Sometimes supports_usb_power_delivery reports incorrect value.

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Hi Heikki,

While testing with different type-c phones available in the market,
With some phones, I noticed that supports_usb_power_delivery
reports "no" eventhough an explicit pd contract has been
established. After spending sometime debugging, I noticed that
the root cause of this is that the partner device(acting as source)
takes too long to send the SRC_CAP message. This makes the
underlying TCPM code to report usb_pd set to 0 while initially
calling typec_register_partner. However,since  there is no
provision in the type-c sysfs interface to update
supports_usb_power_delivery once the contract is established,
supports_usb_power_delivery is left to report "no" even if the partner
source device is at present performing Type-C PD.
Is it OK to add a api to enable updating supports_usb_power_delivery
node in the typec sysfs code after typec_register_partner has been
called ? Or do you have other suggestions ? Please advice.

Thanks & Regards,
Badhri.

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Sometimes supports_usb_power_delivery reports incorrect value. Badhri Jagan Sridharan <badhri@google.com> - 2017-08-14 21:00 +0200
  Re: Sometimes supports_usb_power_delivery reports incorrect value. Heikki Krogerus <heikki.krogerus@linux.intel.com> - 2017-08-15 15:50 +0200
    Re: Sometimes supports_usb_power_delivery reports incorrect value. Badhri Jagan Sridharan <badhri@google.com> - 2017-08-15 16:20 +0200
      Re: Sometimes supports_usb_power_delivery reports incorrect value. Badhri Jagan Sridharan <badhri@google.com> - 2017-08-16 01:30 +0200
        Re: Sometimes supports_usb_power_delivery reports incorrect value. Heikki Krogerus <heikki.krogerus@linux.intel.com> - 2017-08-16 14:40 +0200

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