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=-13.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 CBBD6C433ED for ; Mon, 3 May 2021 07:03:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ACBBF61244 for ; Mon, 3 May 2021 07:03:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232911AbhECHER (ORCPT ); Mon, 3 May 2021 03:04:17 -0400 Received: from mga04.intel.com ([192.55.52.120]:58578 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230364AbhECHEQ (ORCPT ); Mon, 3 May 2021 03:04:16 -0400 IronPort-SDR: XDOQ18ICv6CFLJwzuv6W71BXb4D6PNm8JlIJzbGsTGfZmOcCMHNBivxCFShFcVMVYHCQbs0D3n EQbwBzwvpaxg== X-IronPort-AV: E=McAfee;i="6200,9189,9972"; a="195623104" X-IronPort-AV: E=Sophos;i="5.82,268,1613462400"; d="scan'208";a="195623104" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 May 2021 00:03:24 -0700 IronPort-SDR: 8oUrSgV9yXCo5Cm43B7qOj8sJVx+aSfGmPPcGnjngUowaibMAHeNx+3rfGhN+1u8N39eOMJivi 5pI8WiUeO9zw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,268,1613462400"; d="scan'208";a="530264371" Received: from kuha.fi.intel.com ([10.237.72.162]) by fmsmga001.fm.intel.com with SMTP; 03 May 2021 00:03:21 -0700 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Mon, 03 May 2021 10:03:20 +0300 Date: Mon, 3 May 2021 10:03:20 +0300 From: Heikki Krogerus To: Jack Pham Cc: Greg KH , Subbaraman Narayanamurthy , linux-usb@vger.kernel.org, stable@vger.kernel.org, Abhilash K V Subject: Re: [PATCH] usb: typec: ucsi: Retrieve all the PDOs instead of just the first 4 Message-ID: References: <20210426191825.30721-1-jackp@codeaurora.org> <20210426192605.GB20698@jackp-linux.qualcomm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210426192605.GB20698@jackp-linux.qualcomm.com> Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Hi, On Mon, Apr 26, 2021 at 12:26:05PM -0700, Jack Pham wrote: > Forgot to Cc: Abhilash who introduced the PDO code > > On Mon, Apr 26, 2021 at 12:18:25PM -0700, Jack Pham wrote: > > commit 4dbc6a4ef06d ("usb: typec: ucsi: save power data objects > > in PD mode") introduced retrieval of the PDOs when connected to a > > PD-capable source. But only the first 4 PDOs are received since > > that is the maximum number that can be fetched at a time given the > > MESSAGE_IN length limitation (16 bytes). However, as per the PD spec > > a connected source may advertise up to a maximum of 7 PDOs. > > > > If such a source is connected it's possible the UCSI FW could have > > negotiated a power contract with one of the PDOs at index greater > > than 4, and would be reflected in the request data object's (RDO) > > object position field. This would result in an out-of-bounds access > > when the rdo_index() is used to index into the src_pdos array in > > ucsi_psy_get_voltage_now(). > > > > We can resolve this by instead retrieving and storing up to the > > maximum of 7 PDOs in the con->src_pdos array. This would involve > > two calls to the GET_PDOS command. This makes sense to me. A few nitpicks below. Besides those: Reviewed-by: Heikki Krogerus > > Fixes: 992a60ed0d5e ("usb: typec: ucsi: register with power_supply class") > > Fixes: 4dbc6a4ef06d ("usb: typec: ucsi: save power data objects in PD mode") > > Cc: stable@vger.kernel.org > > Signed-off-by: Jack Pham > > --- > > drivers/usb/typec/ucsi/ucsi.c | 41 +++++++++++++++++++++++++++-------- > > drivers/usb/typec/ucsi/ucsi.h | 6 +++-- > > 2 files changed, 36 insertions(+), 11 deletions(-) > > > > diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c > > index 244270755ae6..ac214b855986 100644 > > --- a/drivers/usb/typec/ucsi/ucsi.c > > +++ b/drivers/usb/typec/ucsi/ucsi.c > > @@ -495,7 +495,8 @@ static void ucsi_unregister_altmodes(struct ucsi_connector *con, u8 recipient) > > } > > } > > > > -static void ucsi_get_pdos(struct ucsi_connector *con, int is_partner) > > +static int ucsi_get_pdos(struct ucsi_connector *con, int is_partner, > > + u32 *pdos, int offset, int num_pdos) That should be aligned properly. > > { > > struct ucsi *ucsi = con->ucsi; > > u64 command; > > @@ -503,17 +504,39 @@ static void ucsi_get_pdos(struct ucsi_connector *con, int is_partner) > > > > command = UCSI_COMMAND(UCSI_GET_PDOS) | UCSI_CONNECTOR_NUMBER(con->num); > > command |= UCSI_GET_PDOS_PARTNER_PDO(is_partner); > > - command |= UCSI_GET_PDOS_NUM_PDOS(UCSI_MAX_PDOS - 1); > > + command |= UCSI_GET_PDOS_PDO_OFFSET(offset); > > + command |= UCSI_GET_PDOS_NUM_PDOS(num_pdos - 1); > > command |= UCSI_GET_PDOS_SRC_PDOS; > > - ret = ucsi_send_command(ucsi, command, con->src_pdos, > > - sizeof(con->src_pdos)); > > - if (ret < 0) { > > + ret = ucsi_send_command(ucsi, command, pdos + offset, > > + num_pdos * sizeof(u32)); That too. I think if you run scripts/checkpatch.pl it will complain about those. > > + if (ret < 0) > > dev_err(ucsi->dev, "UCSI_GET_PDOS failed (%d)\n", ret); > > + if (ret == 0 && offset == 0) > > + dev_warn(ucsi->dev, "UCSI_GET_PDOS returned 0 bytes\n"); > > + > > + return ret; > > +} > > + > > +static void ucsi_get_src_pdos(struct ucsi_connector *con, int is_partner) > > +{ > > + int ret; > > + > > + /* UCSI max payload means only getting at most 4 PDOs at a time */ > > + ret = ucsi_get_pdos(con, 1, con->src_pdos, 0, UCSI_MAX_PDOS); > > + if (ret < 0) > > return; > > - } > > + > > con->num_pdos = ret / sizeof(u32); /* number of bytes to 32-bit PDOs */ > > - if (ret == 0) > > - dev_warn(ucsi->dev, "UCSI_GET_PDOS returned 0 bytes\n"); > > + if (con->num_pdos < UCSI_MAX_PDOS) > > + return; > > + > > + /* get the remaining PDOs, if any */ > > + ret = ucsi_get_pdos(con, 1, con->src_pdos, UCSI_MAX_PDOS, > > + PDO_MAX_OBJECTS - UCSI_MAX_PDOS); > > + if (ret < 0) > > + return; > > + > > + con->num_pdos += ret / sizeof(u32); > > } > > > > static void ucsi_pwr_opmode_change(struct ucsi_connector *con) > > @@ -522,7 +545,7 @@ static void ucsi_pwr_opmode_change(struct ucsi_connector *con) > > case UCSI_CONSTAT_PWR_OPMODE_PD: > > con->rdo = con->status.request_data_obj; > > typec_set_pwr_opmode(con->port, TYPEC_PWR_MODE_PD); > > - ucsi_get_pdos(con, 1); > > + ucsi_get_src_pdos(con, 1); > > break; > > case UCSI_CONSTAT_PWR_OPMODE_TYPEC1_5: > > con->rdo = 0; > > diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h > > index 3920e20a9e9e..cee666790907 100644 > > --- a/drivers/usb/typec/ucsi/ucsi.h > > +++ b/drivers/usb/typec/ucsi/ucsi.h > > @@ -8,6 +8,7 @@ > > #include > > #include > > #include > > +#include > > #include > > > > /* -------------------------------------------------------------------------- */ > > @@ -134,7 +135,9 @@ void ucsi_connector_change(struct ucsi *ucsi, u8 num); > > > > /* GET_PDOS command bits */ > > #define UCSI_GET_PDOS_PARTNER_PDO(_r_) ((u64)(_r_) << 23) > > +#define UCSI_GET_PDOS_PDO_OFFSET(_r_) ((u64)(_r_) << 24) > > #define UCSI_GET_PDOS_NUM_PDOS(_r_) ((u64)(_r_) << 32) > > +#define UCSI_MAX_PDOS (4) > > #define UCSI_GET_PDOS_SRC_PDOS ((u64)1 << 34) > > > > /* -------------------------------------------------------------------------- */ > > @@ -302,7 +305,6 @@ struct ucsi { > > > > #define UCSI_MAX_SVID 5 > > #define UCSI_MAX_ALTMODES (UCSI_MAX_SVID * 6) > > -#define UCSI_MAX_PDOS (4) > > > > #define UCSI_TYPEC_VSAFE5V 5000 > > #define UCSI_TYPEC_1_5_CURRENT 1500 > > @@ -330,7 +332,7 @@ struct ucsi_connector { > > struct power_supply *psy; > > struct power_supply_desc psy_desc; > > u32 rdo; > > - u32 src_pdos[UCSI_MAX_PDOS]; > > + u32 src_pdos[PDO_MAX_OBJECTS]; > > int num_pdos; > > > > struct usb_role_switch *usb_role_sw; thanks, -- heikki