From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751409AbdH0RV6 (ORCPT ); Sun, 27 Aug 2017 13:21:58 -0400 Received: from bh-25.webhostbox.net ([208.91.199.152]:40030 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751182AbdH0RV5 (ORCPT ); Sun, 27 Aug 2017 13:21:57 -0400 Date: Sun, 27 Aug 2017 10:21:56 -0700 From: Guenter Roeck To: Badhri Jagan Sridharan Cc: Greg Kroah-Hartman , devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 4/6] staging: usb: tcpm: usb: type-c: tcpm: Check for Rp for tPDDebounce Message-ID: <20170827172156.GN22819@roeck-us.net> References: <20170827052449.12334-1-Badhri@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170827052449.12334-1-Badhri@google.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Authenticated_sender: guenter@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: guenter@roeck-us.net X-Authenticated-Sender: bh-25.webhostbox.net: guenter@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Aug 26, 2017 at 10:24:49PM -0700, Badhri Jagan Sridharan wrote: > According the spec, the following is the conditions for exiting Try.SNK > state: > "The port shall wait for tDRPTry and only then begin monitoring the CC1 and > CC2 pins for the SNK.Rp state. The port shall then transition to > Attached.SNK when the SNK.Rp state is detected on exactly one of the CC1 > or CC2 pins for at least tPDDebounce and V BUS is detected. Alternatively, > the port shall transition to TryWait.SRC if SNK.Rp state is not detected > for tPDDebounce." > > Signed-off-by: Badhri Jagan Sridharan Reviewed-by: Guenter Roeck > --- > drivers/staging/typec/tcpm.c | 68 ++++++++++++++++---------------------------- > 1 file changed, 24 insertions(+), 44 deletions(-) > > diff --git a/drivers/staging/typec/tcpm.c b/drivers/staging/typec/tcpm.c > index d45ffa8f2cfd..7eed04698ebe 100644 > --- a/drivers/staging/typec/tcpm.c > +++ b/drivers/staging/typec/tcpm.c > @@ -105,6 +105,8 @@ > \ > S(SNK_TRY), \ > S(SNK_TRY_WAIT), \ > + S(SNK_TRY_WAIT_DEBOUNCE), \ > + S(SNK_TRY_WAIT_DEBOUNCE_CHECK_VBUS), \ > S(SRC_TRYWAIT), \ > S(SRC_TRYWAIT_DEBOUNCE), \ > S(SRC_TRYWAIT_UNATTACHED), \ > @@ -2202,18 +2204,24 @@ static void run_state_machine(struct tcpm_port *port) > tcpm_set_state(port, SNK_TRY_WAIT, PD_T_DRP_TRY); > break; > case SNK_TRY_WAIT: > + if (tcpm_port_is_sink(port)) { > + tcpm_set_state(port, SNK_TRY_WAIT_DEBOUNCE, 0); > + } else { > + tcpm_set_state(port, SRC_TRYWAIT, 0); > + port->max_wait = 0; > + } > + break; > + case SNK_TRY_WAIT_DEBOUNCE: > + tcpm_set_state(port, SNK_TRY_WAIT_DEBOUNCE_CHECK_VBUS, > + PD_T_PD_DEBOUNCE); > + break; > + case SNK_TRY_WAIT_DEBOUNCE_CHECK_VBUS: > if (port->vbus_present && tcpm_port_is_sink(port)) { > tcpm_set_state(port, SNK_ATTACHED, 0); > - break; > - } > - if (!tcpm_port_is_sink(port)) { > - tcpm_set_state(port, SRC_TRYWAIT, > - PD_T_PD_DEBOUNCE); > + } else { > + tcpm_set_state(port, SRC_TRYWAIT, 0); > port->max_wait = 0; > - break; > } > - /* No vbus, cc state is sink or open */ > - tcpm_set_state(port, SRC_TRYWAIT_UNATTACHED, PD_T_DRP_TRYWAIT); > break; > case SRC_TRYWAIT: > tcpm_set_cc(port, tcpm_rp_cc(port)); > @@ -2921,20 +2929,12 @@ static void _tcpm_cc_change(struct tcpm_port *port, enum typec_cc_status cc1, > if (port->vbus_present || !tcpm_port_is_source(port)) > tcpm_set_state(port, SRC_TRYWAIT, 0); > break; > - case SNK_TRY_WAIT: > - if (port->vbus_present && tcpm_port_is_sink(port)) { > - tcpm_set_state(port, SNK_ATTACHED, 0); > - break; > + case SNK_TRY_WAIT_DEBOUNCE: > + if (!tcpm_port_is_sink(port)) { > + port->max_wait = 0; > + tcpm_set_state(port, SRC_TRYWAIT, 0); > } > - if (!tcpm_port_is_sink(port)) > - new_state = SRC_TRYWAIT; > - else > - new_state = SRC_TRYWAIT_UNATTACHED; > - > - if (new_state != port->delayed_state) > - tcpm_set_state(port, SNK_TRY_WAIT, 0); > break; > - > case SRC_TRY: > if (tcpm_port_is_source(port)) > tcpm_set_state(port, SRC_TRY_DEBOUNCE, 0); > @@ -2974,8 +2974,6 @@ static void _tcpm_cc_change(struct tcpm_port *port, enum typec_cc_status cc1, > > static void _tcpm_pd_vbus_on(struct tcpm_port *port) > { > - enum tcpm_state new_state; > - > tcpm_log_force(port, "VBUS on"); > port->vbus_present = true; > switch (port->state) { > @@ -3011,18 +3009,8 @@ static void _tcpm_pd_vbus_on(struct tcpm_port *port) > case SRC_TRYWAIT_DEBOUNCE: > tcpm_set_state(port, SRC_TRYWAIT, 0); > break; > - case SNK_TRY_WAIT: > - if (tcpm_port_is_sink(port)) { > - tcpm_set_state(port, SNK_ATTACHED, 0); > - break; > - } > - if (!tcpm_port_is_sink(port)) > - new_state = SRC_TRYWAIT; > - else > - new_state = SRC_TRYWAIT_UNATTACHED; > - > - if (new_state != port->delayed_state) > - tcpm_set_state(port, SNK_TRY_WAIT, 0); > + case SNK_TRY_WAIT_DEBOUNCE: > + /* Do nothing, waiting for PD_DEBOUNCE to do be done */ > break; > case SNK_TRYWAIT: > tcpm_set_state(port, SNK_TRYWAIT_VBUS, 0); > @@ -3035,8 +3023,6 @@ static void _tcpm_pd_vbus_on(struct tcpm_port *port) > > static void _tcpm_pd_vbus_off(struct tcpm_port *port) > { > - enum tcpm_state new_state; > - > tcpm_log_force(port, "VBUS off"); > port->vbus_present = false; > port->vbus_never_low = false; > @@ -3058,14 +3044,8 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port) > if (tcpm_port_is_source(port)) > tcpm_set_state(port, SRC_TRYWAIT_DEBOUNCE, 0); > break; > - case SNK_TRY_WAIT: > - if (!tcpm_port_is_sink(port)) > - new_state = SRC_TRYWAIT; > - else > - new_state = SRC_TRYWAIT_UNATTACHED; > - > - if (new_state != port->delayed_state) > - tcpm_set_state(port, SNK_TRY_WAIT, 0); > + case SNK_TRY_WAIT_DEBOUNCE: > + /* Do nothing, waiting for PD_DEBOUNCE to do be done */ > break; > case SNK_TRYWAIT_VBUS: > tcpm_set_state(port, SNK_TRYWAIT, 0); > -- > 2.14.1.342.g6490525c54-goog >