From patchwork Sun Aug 9 14:19:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 11706719 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2FF8C13B1 for ; Sun, 9 Aug 2020 14:19:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 186F8206B6 for ; Sun, 9 Aug 2020 14:19:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="C4Sf99CA" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726380AbgHIOTT (ORCPT ); Sun, 9 Aug 2020 10:19:19 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:29719 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726307AbgHIOTR (ORCPT ); Sun, 9 Aug 2020 10:19:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1596982754; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ZDOjCziwIkF/d475Xu2YYuhS91BTpqJ+RjuMawHUmUM=; b=C4Sf99CANwU7Xv9zTjYLCywCQSj9Ksa8ndGiuNucn5zb1f/EF0rgtZx/YBXNTnC/CVHNB1 KgcLW2h2AozyghM7jxgZ/iq39xXwUVN4Mve5xX0SodiF3TgwA9Xu2s+c0CUl77IARGP9IE 4auvvp4Ny8MdE67gKZb72z2/TKbguY8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-146-6KsZi2IGO6S3Z1etxWzRWA-1; Sun, 09 Aug 2020 10:19:12 -0400 X-MC-Unique: 6KsZi2IGO6S3Z1etxWzRWA-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A8986107ACCA; Sun, 9 Aug 2020 14:19:11 +0000 (UTC) Received: from x1.localdomain.com (ovpn-112-24.ams2.redhat.com [10.36.112.24]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6F23B8953D; Sun, 9 Aug 2020 14:19:10 +0000 (UTC) From: Hans de Goede To: Greg Kroah-Hartman , Guenter Roeck , Heikki Krogerus Cc: Hans de Goede , linux-usb@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH 3/4] usb: typec: ucsi: Rework ppm_lock handling Date: Sun, 9 Aug 2020 16:19:03 +0200 Message-Id: <20200809141904.4317-4-hdegoede@redhat.com> In-Reply-To: <20200809141904.4317-1-hdegoede@redhat.com> References: <20200809141904.4317-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org The ppm_lock really only needs to be hold during 2 functions: ucsi_reset_ppm() and ucsi_run_command(). Push the taking of the lock down into these 2 functions, renaming ucsi_run_command() to ucsi_send_command() which was an existing wrapper already taking the lock for its callers. This simplifies things for the callers and removes the difference between ucsi_send_command() and ucsi_run_command() which has led to various locking bugs in the past. Cc: stable@vger.kernel.org Signed-off-by: Hans de Goede --- drivers/usb/typec/ucsi/ucsi.c | 56 ++++++++++++++--------------------- 1 file changed, 22 insertions(+), 34 deletions(-) diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index 2f586d6c54f4..182e34aa65ed 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -146,42 +146,33 @@ static int ucsi_exec_command(struct ucsi *ucsi, u64 cmd) return UCSI_CCI_LENGTH(cci); } -static int ucsi_run_command(struct ucsi *ucsi, u64 command, - void *data, size_t size) +int ucsi_send_command(struct ucsi *ucsi, u64 command, + void *data, size_t size) { u8 length; int ret; - WARN_ON(!mutex_is_locked(&ucsi->ppm_lock)); + mutex_lock(&ucsi->ppm_lock); ret = ucsi_exec_command(ucsi, command); if (ret < 0) - return ret; + goto out; length = ret; if (data) { ret = ucsi->ops->read(ucsi, UCSI_MESSAGE_IN, data, size); if (ret) - return ret; + goto out; } ret = ucsi_acknowledge_command(ucsi); if (ret) - return ret; - - return length; -} + goto out; -int ucsi_send_command(struct ucsi *ucsi, u64 command, - void *retval, size_t size) -{ - int ret; - - mutex_lock(&ucsi->ppm_lock); - ret = ucsi_run_command(ucsi, command, retval, size); + ret = length; +out: mutex_unlock(&ucsi->ppm_lock); - return ret; } EXPORT_SYMBOL_GPL(ucsi_send_command); @@ -738,20 +729,24 @@ static int ucsi_reset_ppm(struct ucsi *ucsi) u32 cci; int ret; + mutex_lock(&ucsi->ppm_lock); + ret = ucsi->ops->async_write(ucsi, UCSI_CONTROL, &command, sizeof(command)); if (ret < 0) - return ret; + goto out; tmo = jiffies + msecs_to_jiffies(UCSI_TIMEOUT_MS); do { - if (time_is_before_jiffies(tmo)) - return -ETIMEDOUT; + if (time_is_before_jiffies(tmo)) { + ret = -ETIMEDOUT; + goto out; + } ret = ucsi->ops->read(ucsi, UCSI_CCI, &cci, sizeof(cci)); if (ret) - return ret; + goto out; /* If the PPM is still doing something else, reset it again. */ if (cci & ~UCSI_CCI_RESET_COMPLETE) { @@ -759,13 +754,15 @@ static int ucsi_reset_ppm(struct ucsi *ucsi) &command, sizeof(command)); if (ret < 0) - return ret; + goto out; } msleep(20); } while (!(cci & UCSI_CCI_RESET_COMPLETE)); - return 0; +out: + mutex_unlock(&ucsi->ppm_lock); + return ret; } static int ucsi_role_cmd(struct ucsi_connector *con, u64 command) @@ -777,9 +774,7 @@ static int ucsi_role_cmd(struct ucsi_connector *con, u64 command) u64 c; /* PPM most likely stopped responding. Resetting everything. */ - mutex_lock(&con->ucsi->ppm_lock); ucsi_reset_ppm(con->ucsi); - mutex_unlock(&con->ucsi->ppm_lock); c = UCSI_SET_NOTIFICATION_ENABLE | con->ucsi->ntfy; ucsi_send_command(con->ucsi, c, NULL, 0); @@ -1010,8 +1005,6 @@ int ucsi_init(struct ucsi *ucsi) int ret; int i; - mutex_lock(&ucsi->ppm_lock); - /* Reset the PPM */ ret = ucsi_reset_ppm(ucsi); if (ret) { @@ -1022,13 +1015,13 @@ int ucsi_init(struct ucsi *ucsi) /* Enable basic notifications */ ucsi->ntfy = UCSI_ENABLE_NTFY_CMD_COMPLETE | UCSI_ENABLE_NTFY_ERROR; command = UCSI_SET_NOTIFICATION_ENABLE | ucsi->ntfy; - ret = ucsi_run_command(ucsi, command, NULL, 0); + ret = ucsi_send_command(ucsi, command, NULL, 0); if (ret < 0) goto err_reset; /* Get PPM capabilities */ command = UCSI_GET_CAPABILITY; - ret = ucsi_run_command(ucsi, command, &ucsi->cap, sizeof(ucsi->cap)); + ret = ucsi_send_command(ucsi, command, &ucsi->cap, sizeof(ucsi->cap)); if (ret < 0) goto err_reset; @@ -1045,8 +1038,6 @@ int ucsi_init(struct ucsi *ucsi) goto err_reset; } - mutex_unlock(&ucsi->ppm_lock); - /* Register all connectors */ for (i = 0; i < ucsi->cap.num_connectors; i++) { ret = ucsi_register_port(ucsi, i); @@ -1072,12 +1063,9 @@ int ucsi_init(struct ucsi *ucsi) con->port = NULL; } - mutex_lock(&ucsi->ppm_lock); err_reset: ucsi_reset_ppm(ucsi); err: - mutex_unlock(&ucsi->ppm_lock); - return ret; } EXPORT_SYMBOL_GPL(ucsi_init);