Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751447AbdH0RWc (ORCPT ); Sun, 27 Aug 2017 13:22:32 -0400 Received: from bh-25.webhostbox.net ([208.91.199.152]:47440 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751182AbdH0RWb (ORCPT ); Sun, 27 Aug 2017 13:22:31 -0400 Date: Sun, 27 Aug 2017 10:22:29 -0700 From: Guenter Roeck To: Badhri Jagan Sridharan Cc: Greg Kroah-Hartman , devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 5/6] staging: usb: tcpm: usb: typec: tcpm: Follow Try.SRC exit requirements Message-ID: <20170827172229.GO22819@roeck-us.net> References: <20170827052507.12440-1-Badhri@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170827052507.12440-1-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 Content-Length: 3245 Lines: 103 On Sat, Aug 26, 2017 at 10:25:07PM -0700, Badhri Jagan Sridharan wrote: > According to spec: > " 4.5.2.2.9.2 Exiting from Try.SRC State: > The port shall transition to Attached.SRC when the SRC.Rd > state is detected on exactly one of the CC1 or CC2 pins for > at least tPDDebounce. The port shall transition to > TryWait.SNK after tDRPTry and the SRC.Rd state has not been > detected." > > Signed-off-by: Badhri Jagan Sridharan Reviewed-by: Guenter Roeck > --- > drivers/staging/typec/tcpm.c | 33 ++++++++++++++++++++++++++++----- > 1 file changed, 28 insertions(+), 5 deletions(-) > > diff --git a/drivers/staging/typec/tcpm.c b/drivers/staging/typec/tcpm.c > index 7eed04698ebe..fc179bdea7e4 100644 > --- a/drivers/staging/typec/tcpm.c > +++ b/drivers/staging/typec/tcpm.c > @@ -112,6 +112,7 @@ > S(SRC_TRYWAIT_UNATTACHED), \ > \ > S(SRC_TRY), \ > + S(SRC_TRY_WAIT), \ > S(SRC_TRY_DEBOUNCE), \ > S(SNK_TRYWAIT), \ > S(SNK_TRYWAIT_DEBOUNCE), \ > @@ -2158,6 +2159,7 @@ static void run_state_machine(struct tcpm_port *port) > { > int ret; > enum typec_pwr_opmode opmode; > + unsigned int msecs; > > port->enter_state = port->state; > switch (port->state) { > @@ -2379,7 +2381,22 @@ static void run_state_machine(struct tcpm_port *port) > case SRC_TRY: > port->try_src_count++; > tcpm_set_cc(port, tcpm_rp_cc(port)); > - tcpm_set_state(port, SNK_TRYWAIT, PD_T_DRP_TRY); > + port->max_wait = 0; > + tcpm_set_state(port, SRC_TRY_WAIT, 0); > + break; > + case SRC_TRY_WAIT: > + if (port->max_wait == 0) { > + port->max_wait = jiffies + > + msecs_to_jiffies(PD_T_DRP_TRY); > + msecs = PD_T_DRP_TRY; > + } else { > + if (time_is_after_jiffies(port->max_wait)) > + msecs = jiffies_to_msecs(port->max_wait - > + jiffies); > + else > + msecs = 0; > + } > + tcpm_set_state(port, SNK_TRYWAIT, msecs); > break; > case SRC_TRY_DEBOUNCE: > tcpm_set_state(port, SRC_ATTACHED, PD_T_PD_DEBOUNCE); > @@ -2935,12 +2952,12 @@ static void _tcpm_cc_change(struct tcpm_port *port, enum typec_cc_status cc1, > tcpm_set_state(port, SRC_TRYWAIT, 0); > } > break; > - case SRC_TRY: > + case SRC_TRY_WAIT: > if (tcpm_port_is_source(port)) > tcpm_set_state(port, SRC_TRY_DEBOUNCE, 0); > break; > case SRC_TRY_DEBOUNCE: > - tcpm_set_state(port, SRC_TRY, 0); > + tcpm_set_state(port, SRC_TRY_WAIT, 0); > break; > case SNK_TRYWAIT_DEBOUNCE: > if (port->vbus_present) { > @@ -3015,7 +3032,10 @@ static void _tcpm_pd_vbus_on(struct tcpm_port *port) > case SNK_TRYWAIT: > tcpm_set_state(port, SNK_TRYWAIT_VBUS, 0); > break; > - > + case SRC_TRY_WAIT: > + case SRC_TRY_DEBOUNCE: > + /* Do nothing, waiting for sink detection */ > + break; > default: > break; > } > @@ -3069,7 +3089,10 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port) > case PORT_RESET_WAIT_OFF: > tcpm_set_state(port, tcpm_default_state(port), 0); > break; > - > + case SRC_TRY_WAIT: > + case SRC_TRY_DEBOUNCE: > + /* Do nothing, waiting for sink detection */ > + break; > default: > if (port->pwr_role == TYPEC_SINK && > port->attached) > -- > 2.14.1.342.g6490525c54-goog >