Re: [PATCH] usb: typec: tcpm: Fix SINK_DISCOVERY current limit for Rp-default

From: Greg Kroah-Hartman
Date: Thu May 13 2021 - 09:01:19 EST


On Mon, May 10, 2021 at 02:17:56PM -0700, Badhri Jagan Sridharan wrote:
> This is a regression introduced by
> <1373fefc6243cc96b3565f0ffffadfac4ccfb977>
> "Allow slow charging loops to comply to pSnkStby".
>
> When Source advertises Rp-default, tcpm would request 500mA when in
> SINK_DISCOVERY, Type-C spec advises the sink to follow BC1.2 current
> limits when Rp-default is advertised.
> [12750.503381] Requesting mux state 1, usb-role 2, orientation 1
> [12750.503837] state change SNK_ATTACHED -> SNK_STARTUP [rev3 NONE_AMS]
> [12751.003891] state change SNK_STARTUP -> SNK_DISCOVERY
> [12751.003900] Setting voltage/current limit 5000 mV 500 mA
>
> This patch restores the behavior where the tcpm would request 0mA when
> Rp-default is advertised by the source.
> [   73.174252] Requesting mux state 1, usb-role 2, orientation 1
> [   73.174749] state change SNK_ATTACHED -> SNK_STARTUP [rev3 NONE_AMS]
> [   73.674800] state change SNK_STARTUP -> SNK_DISCOVERY
> [   73.674808] Setting voltage/current limit 5000 mV 0 mA
>
> During SNK_DISCOVERY, Cap the current limit to PD_P_SNK_STDBY_MW / 5 only
> for slow_charger_loop case.
>
> Fixes: 1373fefc6243 ("Allow slow charging loops to comply to pSnkStby")

Your string here was incorrect, I'll fix it up this time, but please be
more careful in the future as it will get caught by our scripts.

thanks,

greg k-h