From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B066DC43461 for ; Tue, 15 Sep 2020 12:15:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7B32F2078E for ; Tue, 15 Sep 2020 12:15:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726280AbgIOMPJ (ORCPT ); Tue, 15 Sep 2020 08:15:09 -0400 Received: from mga07.intel.com ([134.134.136.100]:7457 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726537AbgIOMMt (ORCPT ); Tue, 15 Sep 2020 08:12:49 -0400 IronPort-SDR: mp8ew39PG/JY9hTpAjxheHcaR031G1kj/MEoyvlBavRueG4/0jNZ+zUCNfhyJ3oPHhrZUumw0B H3dw3v8yXELQ== X-IronPort-AV: E=McAfee;i="6000,8403,9744"; a="223427217" X-IronPort-AV: E=Sophos;i="5.76,429,1592895600"; d="scan'208";a="223427217" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Sep 2020 05:11:38 -0700 IronPort-SDR: EWk3CrOWwytj+n/jfixJoDsSNngy7reLxXjm6xvpMXl4qGO7DoaxCnOZmmEwlvbMnMUMo7elLw MZCacKUAOaTw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.76,429,1592895600"; d="scan'208";a="409182703" Received: from kuha.fi.intel.com ([10.237.72.162]) by fmsmga001.fm.intel.com with SMTP; 15 Sep 2020 05:11:35 -0700 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Tue, 15 Sep 2020 15:11:34 +0300 Date: Tue, 15 Sep 2020 15:11:34 +0300 From: Heikki Krogerus To: Badhri Jagan Sridharan Cc: Guenter Roeck , Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v6 02/14] usb: typec: tcpci: Add support when hidden tx registers are inaccessible Message-ID: <20200915121134.GC1139641@kuha.fi.intel.com> References: <20200901025927.3596190-1-badhri@google.com> <20200901025927.3596190-3-badhri@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200901025927.3596190-3-badhri@google.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 31, 2020 at 07:59:15PM -0700, Badhri Jagan Sridharan wrote: > TCPCI spec forbids direct access of TX_BUF_BYTE_x register. > The existing version of tcpci driver assumes that those registers > are directly addressible. Add support for tcpci chips which do > not support direct access to TX_BUF_BYTE_x registers. TX_BUF_BYTE_x > can only be accessed by I2C_WRITE_BYTE_COUNT. > > Signed-off-by: Badhri Jagan Sridharan Reviewed-by: Heikki Krogerus > --- > Changes since v1: > - Refactored the code to check for TX_BUF_BYTE_x_hidden as suggested by > Heikki. > - Not formatting the tcpci_pd_transmit to follow the 100 character/line > limit as suggested by Heikki. (Should be a separate change). > - Changing patch version to v6 to fix version number confusion. > --- > drivers/usb/typec/tcpm/tcpci.c | 46 ++++++++++++++++++++++++++-------- > drivers/usb/typec/tcpm/tcpci.h | 8 ++++++ > 2 files changed, 43 insertions(+), 11 deletions(-) > > diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c > index bd80e03b2b6f..7d36d5e2d3f7 100644 > --- a/drivers/usb/typec/tcpm/tcpci.c > +++ b/drivers/usb/typec/tcpm/tcpci.c > @@ -330,23 +330,47 @@ static int tcpci_pd_transmit(struct tcpc_dev *tcpc, > int ret; > > cnt = msg ? pd_header_cnt(header) * 4 : 0; > - ret = regmap_write(tcpci->regmap, TCPC_TX_BYTE_CNT, cnt + 2); > - if (ret < 0) > - return ret; > + /** > + * TCPCI spec forbids direct access of TCPC_TX_DATA. > + * But, since some of the chipsets offer this capability, > + * it's fair to support both. > + */ > + if (tcpci->data->TX_BUF_BYTE_x_hidden) { > + u8 buf[TCPC_TRANSMIT_BUFFER_MAX_LEN] = {0,}; > + u8 pos = 0; > > - ret = tcpci_write16(tcpci, TCPC_TX_HDR, header); > - if (ret < 0) > - return ret; > + /* Payload + header + TCPC_TX_BYTE_CNT */ > + buf[pos++] = cnt + 2; > + > + if (msg) > + memcpy(&buf[pos], &msg->header, sizeof(msg->header)); > + > + pos += sizeof(header); > > - if (cnt > 0) { > - ret = regmap_raw_write(tcpci->regmap, TCPC_TX_DATA, > - &msg->payload, cnt); > + if (cnt > 0) > + memcpy(&buf[pos], msg->payload, cnt); > + > + pos += cnt; > + ret = regmap_raw_write(tcpci->regmap, TCPC_TX_BYTE_CNT, buf, pos); > + if (ret < 0) > + return ret; > + } else { > + ret = regmap_write(tcpci->regmap, TCPC_TX_BYTE_CNT, cnt + 2); > if (ret < 0) > return ret; > + > + ret = tcpci_write16(tcpci, TCPC_TX_HDR, header); > + if (ret < 0) > + return ret; > + > + if (cnt > 0) { > + ret = regmap_raw_write(tcpci->regmap, TCPC_TX_DATA, &msg->payload, cnt); > + if (ret < 0) > + return ret; > + } > } > > - reg = (PD_RETRY_COUNT << TCPC_TRANSMIT_RETRY_SHIFT) | > - (type << TCPC_TRANSMIT_TYPE_SHIFT); > + reg = (PD_RETRY_COUNT << TCPC_TRANSMIT_RETRY_SHIFT) | (type << TCPC_TRANSMIT_TYPE_SHIFT); > ret = regmap_write(tcpci->regmap, TCPC_TRANSMIT, reg); > if (ret < 0) > return ret; > diff --git a/drivers/usb/typec/tcpm/tcpci.h b/drivers/usb/typec/tcpm/tcpci.h > index fd26ca35814c..cf9d8b63adcb 100644 > --- a/drivers/usb/typec/tcpm/tcpci.h > +++ b/drivers/usb/typec/tcpm/tcpci.h > @@ -128,9 +128,17 @@ > #define TCPC_VBUS_VOLTAGE_ALARM_HI_CFG 0x76 > #define TCPC_VBUS_VOLTAGE_ALARM_LO_CFG 0x78 > > +/* I2C_WRITE_BYTE_COUNT + 1 when TX_BUF_BYTE_x is only accessible I2C_WRITE_BYTE_COUNT */ > +#define TCPC_TRANSMIT_BUFFER_MAX_LEN 31 > + > +/* > + * @TX_BUF_BYTE_x_hidden > + * optional; Set when TX_BUF_BYTE_x can only be accessed through I2C_WRITE_BYTE_COUNT. > + */ > struct tcpci; > struct tcpci_data { > struct regmap *regmap; > + unsigned char TX_BUF_BYTE_x_hidden:1; > int (*init)(struct tcpci *tcpci, struct tcpci_data *data); > int (*set_vconn)(struct tcpci *tcpci, struct tcpci_data *data, > bool enable); > -- > 2.28.0.402.g5ffc5be6b7-goog -- heikki