RE: [RFC PATCH v3 1/2] usb: typec: USB Type-C Port Manager (tcpm)

From: Jun Li
Date: Mon Sep 12 2016 - 01:48:24 EST


Hi Guenter

> -----Original Message-----
> From: Guenter Roeck [mailto:groeck@xxxxxxxxxx]
> Sent: Saturday, September 10, 2016 10:23 AM
> To: Jun Li <jun.li@xxxxxxx>
> Cc: Guenter Roeck <groeck@xxxxxxxxxxxx>; Felipe Balbi
> <felipe.balbi@xxxxxxxxxxxxxxx>; Chandra Sekhar Anagani
> <chandra.sekhar.anagani@xxxxxxxxx>; Bruce Ashfield
> <bruce.ashfield@xxxxxxxxxxxxx>; Bin Gao <bin.gao@xxxxxxxxx>; Pranav Tipnis
> <pranav.tipnis@xxxxxxxxx>; Heikki Krogerus
> <heikki.krogerus@xxxxxxxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; linux-
> usb@xxxxxxxxxxxxxxx
> Subject: Re: [RFC PATCH v3 1/2] usb: typec: USB Type-C Port Manager (tcpm)
>
> On Fri, Sep 9, 2016 at 5:26 PM, Jun Li <jun.li@xxxxxxx> wrote:
> > Hi Guenter,
> >
> >> -----Original Message-----
> >> From: linux-usb-owner@xxxxxxxxxxxxxxx [mailto:linux-usb-
> >> owner@xxxxxxxxxxxxxxx] On Behalf Of Guenter Roeck
> >> Sent: Wednesday, August 24, 2016 5:11 AM
> >> To: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
> >> Cc: Chandra Sekhar Anagani <chandra.sekhar.anagani@xxxxxxxxx>; Bruce
> >> Ashfield <bruce.ashfield@xxxxxxxxxxxxx>; Bin Gao <bin.gao@xxxxxxxxx>;
> >> Pranav Tipnis <pranav.tipnis@xxxxxxxxx>; Heikki Krogerus
> >> <heikki.krogerus@xxxxxxxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx;
> >> linux- usb@xxxxxxxxxxxxxxx; Guenter Roeck <groeck@xxxxxxxxxxxx>
> >> Subject: [RFC PATCH v3 1/2] usb: typec: USB Type-C Port Manager
> >> (tcpm)
> >>
> >> This driver implements the USB Type-C Power Delivery state machine
> >> for both source and sink ports. Alternate mode support is not fully
> >> implemented.
> >>
> >> The driver attaches to the USB Type-C class code implemented in the
> >> following patches.
> >>
> >> usb: typec: add driver for Intel Whiskey Cove PMIC USB Type-C PHY
> >> usb: USB Type-C connector class
> >>
> >> This driver only implements the state machine. Lower level drivers
> >> are responsible for
> >> - Reporting VBUS status and activating VBUS
> >> - Setting CC lines and providing CC line status
> >> - Setting line polarity
> >> - Activating and deactivating VCONN
> >> - Setting the current limit
> >> - Activating and deactivating PD message transfers
> >> - Sending and receiving PD messages
> >>
> >> The driver provides both a functional API as well as callbacks for
> >> lower level drivers.
> >>
> >> Signed-off-by: Guenter Roeck <groeck@xxxxxxxxxxxx>
> >> ---
> >
> > A specific question, if power sink wants to request a new power level
> > after SNK_READY, how to handle it with this tcpm?
> >
>
> So far I have considered the required power level to be static, based on
> our curent implementations. That should be easy to change, though, with an
> additional API function, to be called from a low level driver.
> Do you have that requirement, and would such a function meet your needs ?
>

So you are going to make port->tcpc->config to be dynamic to meet my need?

Li Jun

> Thanks,
> Guenter