From patchwork Thu Dec 7 09:07:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: RD Babiera X-Patchwork-Id: 751595 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="pkaNSg+u" Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D423AD57 for ; Thu, 7 Dec 2023 01:08:03 -0800 (PST) Received: by mail-yb1-xb49.google.com with SMTP id 3f1490d57ef6-db542ec49d9so1051796276.0 for ; Thu, 07 Dec 2023 01:08:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1701940083; x=1702544883; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:from:to:cc:subject:date:message-id :reply-to; bh=o14MGum+47AYWK8DkKGYzjB+QMQESr1NeJbUnOfv+2g=; b=pkaNSg+ub7nGua+JAwYC/Lk7cmaoGKuzEaXp6ZCAHInLwqdq2thPFzZRAAGcZgJbBE o62StJ8wvDYw1nusJs6gQF038iVSkoiHib1fE1II1BZJkA9Lm0fIdabmrJI80GnR8kNZ MELEcdX2ZYDsdxPFY+9d3/H2Q1Ejweg0IN5+NCvajQ7AbwePe2LsuiwfoV88H/0URjcx KP6wzl0u5XGTmOhPEk61VmpxJQ/UQMp59RpW4i9J9NE4D0/iOHi+GsGIgI96tlVemcIG +Org3u2jfZAwt2giVhFDXkp5jJ/lCYhTSl3y+aF1CHRdlIwmU9StctIK6PNtV/9fQ5i+ zQYQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701940083; x=1702544883; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=o14MGum+47AYWK8DkKGYzjB+QMQESr1NeJbUnOfv+2g=; b=fd7DYZlGCWR+8hiuYO/ML1cQcdfAXQoxYWlKW/TCBjrBS0DNPNSgV07yWYlQ6vzWn9 yyBSrBz0Z8m9BWRwHJ5qlM0cn+gFDG4X1c9gC0t48nAiVAhZDy1T/D8dHi7MPwhzMido bPGh1AGKYjJghpt46tAHDc86puTJXhBX/STwpU/XutqzfGOoGNE7zQgTqoYBh6KBgahe PYuInqgjXQ9JREEm60NCcrUQrQLkfkMJtlxUW0a1lown22U1rpA4z2lxGYZkCZ4VOflA GM1yRff7tNAZhamjOtWAvDmfpu9h/TeTECrrRtftYWYqCx8CsTkVUSiluO+MFZm6+I2g LGhA== X-Gm-Message-State: AOJu0YyAEASPbrsch0Dezv+RgDsVUrm91PGHi3IV/bdkpS4isDniOu3U MJjaMKH9txu6RrYRvpAB5W3tcWxMxnXC7gE= X-Google-Smtp-Source: AGHT+IESqp84idXc+q5u9MDFeaSljtOtaoFQha272YyPKZC83BfNU4qv0DtqVTF2X+Ygtv8drGCkXxJ3QEblTWk= X-Received: from rdbabiera.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:18a8]) (user=rdbabiera job=sendgmr) by 2002:a25:7489:0:b0:d9a:ec95:9687 with SMTP id p131-20020a257489000000b00d9aec959687mr24783ybc.11.1701940082998; Thu, 07 Dec 2023 01:08:02 -0800 (PST) Date: Thu, 7 Dec 2023 09:07:34 +0000 In-Reply-To: <20231207090738.15721-12-rdbabiera@google.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20231207090738.15721-12-rdbabiera@google.com> X-Developer-Key: i=rdbabiera@google.com; a=openpgp; fpr=639A331F1A21D691815CE090416E17CA2BBBD5C8 X-Developer-Signature: v=1; a=openpgp-sha256; l=9939; i=rdbabiera@google.com; h=from:subject; bh=I/HoHGVc7Oaex23bh6N4rq+2IpkSlsE3QSHESQ/ktpQ=; b=owGbwMvMwCFW0bfok0KS4TbG02pJDKmF3dGPVk3cq3a6ccleW9kk15ORnYuORJfcDBReUNc78 VnotoLDHaUsDGIcDLJiiiy6/nkGN66kbpnDWWMMM4eVCWQIAxenAExk009GhtMlMfuiVouZBT9e viWzJKX/4pucB/fndm3UdN86g/O/dD8jw+rGdZN7lNUezMpZW6dzwawzSmfGms6JtZ/2pLtvnn9 Kgx0A X-Mailer: git-send-email 2.43.0.rc2.451.g8631bc7472-goog Message-ID: <20231207090738.15721-15-rdbabiera@google.com> Subject: [PATCH v1 03/10] usb: typec: tcpm: process receive and transmission of sop' messages From: RD Babiera To: heikki.krogerus@linux.intel.com, linux@roeck-us.net, gregkh@linuxfoundation.org, pmalani@chromium.org, bleung@chromium.org, chrome-platform@lists.linux.dev, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Cc: badhri@google.com, tzungbi@kernel.org, utkarsh.h.patel@intel.com, andriy.shevchenko@linux.intel.com, RD Babiera Add negotiated revision and tx/rx message ids to tcpm_port specific to SOP'. tx_sop_type is added to the tcpm_port to determine whether the current constructed message will be sent over SOP or SOP' if not sent immediately. tcpm_pd_transmit now accounts for the transmit SOP* type, and updates the message ids accordingly. SOP* messages are currently not sent by the tcpm. tcpm_pd_rx_handler updates the received message ids. SOP* messages are not processed afterwards. The handler also calls tcpm_can_communicate_sop_prime to determine if a SOP' message is directed towards the port, and drops SOP' messages it should not respond to. tcpm_can_communicate_sop_prime is added as a helper to determine whether the port is capable of communicating over SOP' at a given moment. Being the Vconn source is a requirement in Power Delivery 3.0 but only a recommendation in Power Delviery 2.0. Because the port should ensure that the cable is powered before communication, always enforce the port is the Vconn source regardless of revision. Signed-off-by: RD Babiera --- drivers/usb/typec/tcpm/tcpm.c | 152 ++++++++++++++++++++++++++++++++-- 1 file changed, 143 insertions(+), 9 deletions(-) diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index 5f9a4691f626..313928f93d0c 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -493,6 +493,35 @@ struct tcpm_port { * transitions. */ bool potential_contaminant; + + /* SOP* Related Fields */ + /* + * tx_sop_type determines which SOP* a message is being sent on. + * For messages that are queued and not sent immediately such as in + * tcpm_queue_message or messages that send after state changes, + * the tx_sop_type should be set accordingly. + */ + enum tcpm_transmit_type tx_sop_type; + /* + * Prior to discovering the port partner's Specification Revision, the + * Vconn source and cable plug will use the lower of their two revisions. + * + * When the port partner's Specification Revision is discovered, the following + * rules are put in place. + * 1. If the cable revision (1) is lower than the revision negotiated + * between the port and partner (2), the port and partner will communicate + * on revision (2), but the port and cable will communicate on revision (1). + * 2. If the cable revision (1) is higher than the revision negotiated + * between the port and partner (2), the port and partner will communicate + * on revision (2), and the port and cable will communicate on revision (2) + * as well. + */ + unsigned int negotiated_rev_prime; + /* + * Each SOP* type must maintain their own tx and rx message IDs + */ + unsigned int message_id_prime; + unsigned int rx_msgid_prime; #ifdef CONFIG_DEBUG_FS struct dentry *dentry; struct mutex logbuffer_lock; /* log buffer access lock */ @@ -882,19 +911,32 @@ static void tcpm_ams_finish(struct tcpm_port *port) } static int tcpm_pd_transmit(struct tcpm_port *port, - enum tcpm_transmit_type type, + enum tcpm_transmit_type tx_sop_type, const struct pd_message *msg) { unsigned long timeout; int ret; + unsigned int negotiated_rev; + + switch (tx_sop_type) { + case TCPC_TX_SOP_PRIME: + negotiated_rev = port->negotiated_rev_prime; + break; + case TCPC_TX_SOP: + negotiated_rev = port->negotiated_rev; + break; + default: + negotiated_rev = port->negotiated_rev; + break; + } if (msg) tcpm_log(port, "PD TX, header: %#x", le16_to_cpu(msg->header)); else - tcpm_log(port, "PD TX, type: %#x", type); + tcpm_log(port, "PD TX, type: %#x", tx_sop_type); reinit_completion(&port->tx_complete); - ret = port->tcpc->pd_transmit(port->tcpc, type, msg, port->negotiated_rev); + ret = port->tcpc->pd_transmit(port->tcpc, tx_sop_type, msg, negotiated_rev); if (ret < 0) return ret; @@ -907,7 +949,20 @@ static int tcpm_pd_transmit(struct tcpm_port *port, switch (port->tx_status) { case TCPC_TX_SUCCESS: - port->message_id = (port->message_id + 1) & PD_HEADER_ID_MASK; + switch (tx_sop_type) { + case TCPC_TX_SOP_PRIME: + port->message_id_prime = (port->message_id_prime + 1) & + PD_HEADER_ID_MASK; + break; + case TCPC_TX_SOP: + port->message_id = (port->message_id + 1) & + PD_HEADER_ID_MASK; + break; + default: + port->message_id = (port->message_id + 1) & + PD_HEADER_ID_MASK; + break; + } /* * USB PD rev 2.0, 8.3.2.2.1: * USB PD rev 3.0, 8.3.2.1.3: @@ -1592,6 +1647,57 @@ static void tcpm_register_partner_altmodes(struct tcpm_port *port) #define supports_modal(port) PD_IDH_MODAL_SUPP((port)->partner_ident.id_header) +/* + * Helper to determine whether the port is capable of SOP' communication at the + * current point in time. + */ +static bool tcpm_can_communicate_sop_prime(struct tcpm_port *port) +{ + /* Check to see if tcpc supports SOP' communication */ + if (!port->tcpc->cable_comm_capable || !port->tcpc->cable_comm_capable(port->tcpc)) + return false; + /* + * Power Delivery 2.0 Section 6.3.11 + * Before communicating with a Cable Plug a Port Should ensure that it + * is the Vconn Source and that the Cable Plugs are powered by + * performing a Vconn swap if necessary. Since it cannot be guaranteed + * that the present Vconn Source is supplying Vconn, the only means to + * ensure that the Cable Plugs are powered is for a Port wishing to + * communicate with a Cable Plug is to become the Vconn Source. + * + * Power Delivery 3.0 Section 6.3.11 + * Before communicating with a Cable Plug a Port Shall ensure that it + * is the Vconn source. + */ + if (port->vconn_role != TYPEC_SOURCE) + return false; + /* + * Power Delivery 2.0 Section 2.4.4 + * When no Contract or an Implicit Contract is in place the Source can + * communicate with a Cable Plug using SOP' packets in order to discover + * its characteristics. + * + * Power Delivery 3.0 Section 2.4.4 + * When no Contract or an Implicit Contract is in place only the Source + * port that is supplying Vconn is allowed to send packets to a Cable + * Plug and is allowed to respond to packets from the Cable Plug. + */ + if (!port->explicit_contract) + return port->pwr_role == TYPEC_SOURCE; + if (port->negotiated_rev == PD_REV30) + return true; + /* + * Power Delivery 2.0 Section 2.4.4 + * + * When an Explicit Contract is in place the DFP (either the Source or + * the Sink) can communicate with the Cable Plug(s) using SOP’/SOP” + * Packets (see Figure 2-3). + */ + if (port->negotiated_rev == PD_REV20) + return port->data_role == TYPEC_HOST; + return false; +} + static int tcpm_pd_svdm(struct tcpm_port *port, struct typec_altmode *adev, const u32 *p, int cnt, u32 *response, enum adev_actions *adev_action) @@ -2984,8 +3090,12 @@ static void tcpm_pd_rx_handler(struct kthread_work *work) enum pd_ctrl_msg_type type = pd_header_type_le(msg->header); unsigned int msgid = pd_header_msgid_le(msg->header); - /* Ignore SOP' for now */ - if (rx_sop_type == TCPC_TX_SOP_PRIME) + /* + * Drop SOP' messages if cannot receive via + * tcpm_can_communicate_sop_prime + */ + if (rx_sop_type == TCPC_TX_SOP_PRIME && + !tcpm_can_communicate_sop_prime(port)) goto done; /* @@ -2997,16 +3107,33 @@ static void tcpm_pd_rx_handler(struct kthread_work *work) * Message). Note: this shall not apply to the Soft_Reset * Message which always has a MessageID value of zero." */ - if (msgid == port->rx_msgid && type != PD_CTRL_SOFT_RESET) + switch (rx_sop_type) { + case TCPC_TX_SOP_PRIME: + if (msgid == port->rx_msgid_prime) + goto done; + port->rx_msgid_prime = msgid; + /* For now, don't do anything with SOP' Messages */ goto done; - port->rx_msgid = msgid; + case TCPC_TX_SOP: + if (msgid == port->rx_msgid && + type != PD_CTRL_SOFT_RESET) + goto done; + port->rx_msgid = msgid; + break; + default: + if (msgid == port->rx_msgid && + type != PD_CTRL_SOFT_RESET) + goto done; + port->rx_msgid = msgid; + break; + } /* * If both ends believe to be DFP/host, we have a data role * mismatch. */ if (!!(le16_to_cpu(msg->header) & PD_HEADER_DATA_ROLE) == - (port->data_role == TYPEC_HOST)) { + (port->data_role == TYPEC_HOST) && rx_sop_type == TCPC_TX_SOP) { tcpm_log(port, "Data role mismatch, initiating error recovery"); tcpm_set_state(port, ERROR_RECOVERY, 0); @@ -3711,6 +3838,7 @@ static void tcpm_reset_port(struct tcpm_port *port) * we can check tcpm_pd_rx_handler() if we had seen it before. */ port->rx_msgid = -1; + port->rx_msgid_prime = -1; port->tcpc->set_pd_rx(port->tcpc, false); tcpm_init_vbus(port); /* also disables charging */ @@ -4025,8 +4153,11 @@ static void run_state_machine(struct tcpm_port *port) port->pwr_opmode = TYPEC_PWR_MODE_USB; port->caps_count = 0; port->negotiated_rev = PD_MAX_REV; + port->negotiated_rev_prime = PD_MAX_REV; port->message_id = 0; + port->message_id_prime = 0; port->rx_msgid = -1; + port->rx_msgid_prime = -1; port->explicit_contract = false; /* SNK -> SRC POWER/FAST_ROLE_SWAP finished */ if (port->ams == POWER_ROLE_SWAP || @@ -4266,8 +4397,11 @@ static void run_state_machine(struct tcpm_port *port) typec_set_pwr_opmode(port->typec_port, opmode); port->pwr_opmode = TYPEC_PWR_MODE_USB; port->negotiated_rev = PD_MAX_REV; + port->negotiated_rev_prime = PD_MAX_REV; port->message_id = 0; + port->message_id_prime = 0; port->rx_msgid = -1; + port->rx_msgid_prime = -1; port->explicit_contract = false; if (port->ams == POWER_ROLE_SWAP ||