From nobody Sat Oct 4 22:34:52 2025 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [185.203.201.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C233E2FABE3 for ; Tue, 12 Aug 2025 17:37:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.201.7 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755020247; cv=none; b=K+J+13Ct/k3Frh5q1V/wzl1VctJpBMAxHUMx6eYah3NXXggn7DojfOxC2bGGv3+pNL2p8nGHwhKHKMem1SXFq6/72/s5aTnonb940/k4SuIYkf2NHappyzF1mBBfDthlYIrSJxx3kNKfeOC5MvHMpP4ISjDO7Oc0gnV3eYLSknI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755020247; c=relaxed/simple; bh=4QosE3H82o+BIBanXec+XaasUKH495dBom5k4ZPKLLY=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=oDPibzHn6ohQSSIZd6A3ZxnocmMdd2kRyrPYGB76dmpt27v6IOCWCFyPDwc+yuBZP4qYf08YJRU9kdLo0PbG7u3Pl9fTbyTNUBVLQwfKeVRde+tCbQHJxx95eExkjvqOqE/FPGNH5TvXKE3E+ARYix3mbqMrNoVMmJSDSW2T9Kw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.201.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ulsw8-0008PA-3C for linux-kernel@vger.kernel.org; Tue, 12 Aug 2025 19:37:24 +0200 Received: from moin.white.stw.pengutronix.de ([2a0a:edc0:0:b01:1d::7b] helo=bjornoya.blackshift.org) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1ulsw7-00DEcq-1S for linux-kernel@vger.kernel.org; Tue, 12 Aug 2025 19:37:23 +0200 Received: from dspam.blackshift.org (localhost [127.0.0.1]) by bjornoya.blackshift.org (Postfix) with SMTP id 215AC456261 for ; Tue, 12 Aug 2025 17:37:23 +0000 (UTC) Received: from hardanger.blackshift.org (unknown [172.20.34.65]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by bjornoya.blackshift.org (Postfix) with ESMTPS id 97DDE456202; Tue, 12 Aug 2025 17:37:17 +0000 (UTC) Received: from hardanger.blackshift.org (localhost [::1]) by hardanger.blackshift.org (OpenSMTPD) with ESMTP id 3a13c453; Tue, 12 Aug 2025 17:37:15 +0000 (UTC) From: Marc Kleine-Budde Date: Tue, 12 Aug 2025 19:36:56 +0200 Subject: [PATCH 6/7] can: m_can: m_can_get_berr_counter(): don't wake up controller if interface is down Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250812-m_can-fix-state-handling-v1-6-b739e06c0a3b@pengutronix.de> References: <20250812-m_can-fix-state-handling-v1-0-b739e06c0a3b@pengutronix.de> In-Reply-To: <20250812-m_can-fix-state-handling-v1-0-b739e06c0a3b@pengutronix.de> To: Chandrasekar Ramakrishnan , Vincent Mailhol , Patrik Flykt , Dong Aisheng , Fengguang Wu , Varka Bhadram , Wu Bo , Markus Schneider-Pargmann , Philipp Zabel Cc: linux-can@vger.kernel.org, linux-kernel@vger.kernel.org, kernel@pengutronix.de, Marc Kleine-Budde X-Mailer: b4 0.15-dev-e44bb X-Developer-Signature: v=1; a=openpgp-sha256; l=892; i=mkl@pengutronix.de; h=from:subject:message-id; bh=4QosE3H82o+BIBanXec+XaasUKH495dBom5k4ZPKLLY=; b=owEBbQGS/pANAwAKAQx0Zd/5kJGcAcsmYgBom3vIsM6EBlLJrHCJog96c4xbEju9IpTsI+k/T KbT31BdFXGJATMEAAEKAB0WIQSf+wzYr2eoX/wVbPMMdGXf+ZCRnAUCaJt7yAAKCRAMdGXf+ZCR nL4yCACSPOZ4Z1UT4XZ7ga6EYHPkwY54dQKAIz7O3DDYrDpzj+4LWAoVBiHjcWlERrPo3Tf4sMN GFqwemcryJT1jKaBDCrSgMdRY6bBhJYWdcCHaBNWo5z5D1cN541nJATqae0QEs1hG1tmDR8s2Ww 5eI5Fd6pnivS5T7Gt9cj2dzygnIQkhXPtVajIRYKFOgi0CnLZ5dj9BQtMgRXLyeDl7hx9a4PTJR wXdhYZ3jfGa5dwaHfTANOMlox/gCx9xPV26M0njs0AjUR0v6LzYW6Y+ZvzS7SDVLKxvBsjKZe16 1rem7Q7vwMCJXrRMG7IJkQDrCZHaKg6rljGcb5UesCxbFVfz X-Developer-Key: i=mkl@pengutronix.de; a=openpgp; fpr=C1400BA0B3989E6FBC7D5B5C2B5EE211C58AEA54 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org If the interface is down, the CAN controller might be powered down, the clock disabled, and/or it's external reset asserted. Don't wake up the controller to read the CAN bus error counters, if the interface is down. Signed-off-by: Marc Kleine-Budde --- drivers/net/can/m_can/m_can.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index 149f3a8b5f7e..c24ea0e5599f 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -790,6 +790,10 @@ static int m_can_get_berr_counter(const struct net_dev= ice *dev, struct m_can_classdev *cdev =3D netdev_priv(dev); int err; =20 + /* Avoid waking up the controller if the interface is down */ + if (!(dev->flags & IFF_UP)) + return 0; + err =3D m_can_clk_start(cdev); if (err) return err; --=20 2.50.1