From nobody Fri Oct 24 20:29:27 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CDD37C28B2C for ; Mon, 15 Aug 2022 21:22:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245321AbiHOVUl (ORCPT ); Mon, 15 Aug 2022 17:20:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55062 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238649AbiHOVM2 (ORCPT ); Mon, 15 Aug 2022 17:12:28 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EE786D9EA7; Mon, 15 Aug 2022 12:19:32 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id BC89260FF6; Mon, 15 Aug 2022 19:19:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9AE23C433D6; Mon, 15 Aug 2022 19:19:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1660591171; bh=jGYDKm0Tw+bfYKYZH5hqWm2mnwiYORDMGSxt/7Z6A0k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qUhPRHp6tfi0WGpfO5cQLjy0UPPpO8MmiTsTBpDucBrVIiqqXnihyvzoRqh+hlZK3 uOX/fQUu9HCHltMciUtkhgGvYqvIL9izPQRg7UIL26dfbHZMvctoXz0lEedhPXcdbH MHHXDbmlw0A8/r7gvT8/2IaKr3dapn3pUx1tKVw0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vincent Mailhol , Marc Kleine-Budde , Sasha Levin Subject: [PATCH 5.18 0493/1095] can: error: specify the values of data[5..7] of CAN error frames Date: Mon, 15 Aug 2022 19:58:12 +0200 Message-Id: <20220815180449.929847988@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220815180429.240518113@linuxfoundation.org> References: <20220815180429.240518113@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Vincent Mailhol [ Upstream commit e70a3263a7eed768d5f947b8f2aff8d2a79c9d97 ] Currently, data[5..7] of struct can_frame, when used as a CAN error frame, are defined as being "controller specific". Device specific behaviours are problematic because it prevents someone from writing code which is portable between devices. As a matter of fact, data[5] is never used, data[6] is always used to report TX error counter and data[7] is always used to report RX error counter. can-utils also relies on this. This patch updates the comment in the uapi header to specify that data[5] is reserved (and thus should not be used) and that data[6..7] are used for error counters. Fixes: 0d66548a10cb ("[CAN]: Add PF_CAN core module") Link: https://lore.kernel.org/all/20220719143550.3681-11-mailhol.vincent@wa= nadoo.fr Signed-off-by: Vincent Mailhol Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin --- include/uapi/linux/can/error.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/can/error.h b/include/uapi/linux/can/error.h index 34633283de64..a1000cb63063 100644 --- a/include/uapi/linux/can/error.h +++ b/include/uapi/linux/can/error.h @@ -120,6 +120,9 @@ #define CAN_ERR_TRX_CANL_SHORT_TO_GND 0x70 /* 0111 0000 */ #define CAN_ERR_TRX_CANL_SHORT_TO_CANH 0x80 /* 1000 0000 */ =20 -/* controller specific additional information / data[5..7] */ +/* data[5] is reserved (do not use) */ + +/* TX error counter / data[6] */ +/* RX error counter / data[7] */ =20 #endif /* _UAPI_CAN_ERROR_H */ --=20 2.35.1