linux-kernel - Re: [PATCH v4 2/3] usb: typec: tcpm: Allow slow charging loops to comply to pSnkStby

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <YHcFxReUDYpbe+4s@kroah.com>
Date:   Wed, 14 Apr 2021 17:09:57 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     Badhri Jagan Sridharan <badhri@...gle.com>
Cc:     Guenter Roeck <linux@...ck-us.net>,
        Heikki Krogerus <heikki.krogerus@...ux.intel.com>,
        Rob Herring <robh+dt@...nel.org>,
        Adam Thomson <Adam.Thomson.Opensource@...semi.com>,
        linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org,
        devicetree@...r.kernel.org, Kyle Tso <kyletso@...gle.com>
Subject: Re: [PATCH v4 2/3] usb: typec: tcpm: Allow slow charging loops to
 comply to pSnkStby

On Wed, Apr 14, 2021 at 07:26:55AM -0700, Badhri Jagan Sridharan wrote:
> When a PD charger advertising Rp-3.0 is connected to a sink port, the
> sink port current limit would 3A, during SNK_DISCOVERY, till power
> negotiation starts. Once the negotiation starts the power limit needs
> to drop down to pSnkStby(500mA @ 5V) and to negotiated current limit
> once the explicit contract is in place. Not all charging loops can ramp
> up to 3A and drop down to 500mA within tSnkStdby which is 15ms. The port
> partner might hard reset if tSnkStdby is not met.
> 
> To solve this problem, this patch introduces slow-charger-loop which
> when set makes the port request PD_P_SNK_STDBY_MW upon entering
> SNK_DISCOVERY(instead of 3A or the 1.5A during SNK_DISCOVERY) and the
> actual currrent limit after RX of PD_CTRL_PSRDY for PD link or during
> SNK_READY for non-pd link.
> 
> Signed-off-by: Badhri Jagan Sridharan <badhri@...gle.com>
> Reviewed-by: Heikki Krogerus <heikki.krogerus@...ux.intel.com>
> ---
> Changes since V3:
> * Added reviewed-by tag from Heikki

No need to add reviewed-by tags, my tools pick that up already.

Patches 1 and 2 now queued up.

thanks,

greg k-h