From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751436AbdH0R0z (ORCPT ); Sun, 27 Aug 2017 13:26:55 -0400 Received: from bh-25.webhostbox.net ([208.91.199.152]:33217 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751182AbdH0R0x (ORCPT ); Sun, 27 Aug 2017 13:26:53 -0400 Date: Sun, 27 Aug 2017 10:26:52 -0700 From: Guenter Roeck To: Badhri Jagan Sridharan Cc: Greg Kroah-Hartman , devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 09/11] staging: typec: tcpm: typec: tcpm: Wait for CC debounce before PD excg Message-ID: <20170827172652.GS22819@roeck-us.net> References: <20170827065127.3226-1-Badhri@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170827065127.3226-1-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 11:51:27PM -0700, Badhri Jagan Sridharan wrote: > Once, Rp or Rd is switched, wait for PD_T_CC_DEBOUNCE. If not the > PS_RDY message transmitted might result in failure. > Also, Only wait for PD_T_SRCSWAPSTDBY while in > PR_SWAP_SRC_SNK_TRANSITION_OFF. PD_T_PS_SOURCE_OFF is the overall > time after which the initial sink would issue hard reset. > > Signed-off-by: Badhri Jagan Sridharan Reviewed-by: Guenter Roeck > --- > drivers/staging/typec/pd.h | 2 ++ > drivers/staging/typec/tcpm.c | 25 ++++++++++++++++++++++--- > 2 files changed, 24 insertions(+), 3 deletions(-) > > diff --git a/drivers/staging/typec/pd.h b/drivers/staging/typec/pd.h > index 510ef7279900..30b32ad72acd 100644 > --- a/drivers/staging/typec/pd.h > +++ b/drivers/staging/typec/pd.h > @@ -278,6 +278,8 @@ static inline unsigned int rdo_max_power(u32 rdo) > #define PD_T_VCONN_SOURCE_ON 100 > #define PD_T_SINK_REQUEST 100 /* 100 ms minimum */ > #define PD_T_ERROR_RECOVERY 100 /* minimum 25 is insufficient */ > +#define PD_T_SRCSWAPSTDBY 625 /* Maximum of 650ms */ > +#define PD_T_NEWSRC 250 /* Maximum of 275ms */ > > #define PD_T_DRP_TRY 100 /* 75 - 150 ms */ > #define PD_T_DRP_TRYWAIT 600 /* 400 - 800 ms */ > diff --git a/drivers/staging/typec/tcpm.c b/drivers/staging/typec/tcpm.c > index 1f6827f32b29..a7da609006f5 100644 > --- a/drivers/staging/typec/tcpm.c > +++ b/drivers/staging/typec/tcpm.c > @@ -90,9 +90,11 @@ > S(PR_SWAP_START), \ > S(PR_SWAP_SRC_SNK_TRANSITION_OFF), \ > S(PR_SWAP_SRC_SNK_SOURCE_OFF), \ > + S(PR_SWAP_SRC_SNK_SOURCE_OFF_CC_DEBOUNCED), \ > S(PR_SWAP_SRC_SNK_SINK_ON), \ > S(PR_SWAP_SNK_SRC_SINK_OFF), \ > S(PR_SWAP_SNK_SRC_SOURCE_ON), \ > + S(PR_SWAP_SNK_SRC_SOURCE_ON_VBUS_RAMPED_UP), \ > \ > S(VCONN_SWAP_ACCEPT), \ > S(VCONN_SWAP_SEND), \ > @@ -1395,7 +1397,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > SNK_TRANSITION_SINK_VBUS, 0); > } > break; > - case PR_SWAP_SRC_SNK_SOURCE_OFF: > + case PR_SWAP_SRC_SNK_SOURCE_OFF_CC_DEBOUNCED: > tcpm_set_state(port, PR_SWAP_SRC_SNK_SINK_ON, 0); > break; > case PR_SWAP_SNK_SRC_SINK_OFF: > @@ -2679,11 +2681,17 @@ static void run_state_machine(struct tcpm_port *port) > case PR_SWAP_SRC_SNK_TRANSITION_OFF: > tcpm_set_vbus(port, false); > port->explicit_contract = false; > + /* allow time for Vbus discharge, must be < tSrcSwapStdby */ > tcpm_set_state(port, PR_SWAP_SRC_SNK_SOURCE_OFF, > - PD_T_PS_SOURCE_OFF); > + PD_T_SRCSWAPSTDBY); > break; > case PR_SWAP_SRC_SNK_SOURCE_OFF: > tcpm_set_cc(port, TYPEC_CC_RD); > + /* allow CC debounce */ > + tcpm_set_state(port, PR_SWAP_SRC_SNK_SOURCE_OFF_CC_DEBOUNCED, > + PD_T_CC_DEBOUNCE); > + break; > + case PR_SWAP_SRC_SNK_SOURCE_OFF_CC_DEBOUNCED: > /* > * USB-PD standard, 6.2.1.4, Port Power Role: > * "During the Power Role Swap Sequence, for the initial Source > @@ -2709,6 +2717,15 @@ static void run_state_machine(struct tcpm_port *port) > case PR_SWAP_SNK_SRC_SOURCE_ON: > tcpm_set_cc(port, tcpm_rp_cc(port)); > tcpm_set_vbus(port, true); > + /* > + * allow time VBUS ramp-up, must be < tNewSrc > + * Also, this window overlaps with CC debounce as well. > + * So, Wait for the max of two which is PD_T_NEWSRC > + */ > + tcpm_set_state(port, PR_SWAP_SNK_SRC_SOURCE_ON_VBUS_RAMPED_UP, > + PD_T_NEWSRC); > + break; > + case PR_SWAP_SNK_SRC_SOURCE_ON_VBUS_RAMPED_UP: > /* > * USB PD standard, 6.2.1.4: > * "Subsequent Messages initiated by the Policy Engine, > @@ -2979,8 +2996,10 @@ static void _tcpm_cc_change(struct tcpm_port *port, enum typec_cc_status cc1, > case PR_SWAP_SNK_SRC_SINK_OFF: > case PR_SWAP_SRC_SNK_TRANSITION_OFF: > case PR_SWAP_SRC_SNK_SOURCE_OFF: > + case PR_SWAP_SRC_SNK_SOURCE_OFF_CC_DEBOUNCED: > + case PR_SWAP_SNK_SRC_SOURCE_ON: > /* > - * CC state change is expected here; we just turned off power. > + * CC state change is expected in PR_SWAP > * Ignore it. > */ > break; > -- > 2.14.1.342.g6490525c54-goog >