From mboxrd@z Thu Jan 1 00:00:00 1970 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 B690A30F959 for ; Tue, 23 Sep 2025 09:18:02 +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=1758619084; cv=none; b=gof0+4ysc6cYzeW0THY1dB5KyIQavCcRGsxBA0xec213pznEIm6v3U8UGLPSMLtUT2zgbep1KPIPYDWCAOppq2JjxLdUQxUaOJCNYd9+0Znn0sSIfsqaZtYTGYhZ6Cq5bt3DhcR87Qnmebaqa3cC2r+EUa2PvIkFOfUwbkIEYIQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758619084; c=relaxed/simple; bh=/HNzMsstKctC8PB7quDVBrjlyGwlmAE7o10zajY1uBc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=DpwT76CpGvJfig5KX6JgpKx4ru7ckhluSH8vwBl+MF/e5Zw2lkZWNJL30GJ4wQQ108MpNkHRVOu+gHcMeJGaCPUQoBMAxLPoZwyZoF0yVgT7okTVc7snq+xJkFAH2hXqvm8+mUsK8kcBrFEv4ookUop2qlKq3rbw4MmrR2b35sE= 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 1v0z9e-0006Xb-2d; Tue, 23 Sep 2025 11:17:46 +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 1v0z9c-0004AP-2e; Tue, 23 Sep 2025 11:17:44 +0200 Received: from hardanger.blackshift.org (p54b152ce.dip0.t-ipconnect.de [84.177.82.206]) (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) (Authenticated sender: mkl-all@blackshift.org) by smtp.blackshift.org (Postfix) with ESMTPSA id 7DC3E477C07; Tue, 23 Sep 2025 09:17:44 +0000 (UTC) From: Marc Kleine-Budde Date: Tue, 23 Sep 2025 11:17:18 +0200 Subject: [PATCH v3 5/6] can: m_can: m_can_get_berr_counter(): don't wake up controller if interface is down Precedence: bulk X-Mailing-List: linux-can@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20250923-m_can-fix-state-handling-v3-5-06d8baccadbf@pengutronix.de> References: <20250923-m_can-fix-state-handling-v3-0-06d8baccadbf@pengutronix.de> In-Reply-To: <20250923-m_can-fix-state-handling-v3-0-06d8baccadbf@pengutronix.de> To: Chandrasekar Ramakrishnan , Vincent Mailhol , Patrik Flykt , Dong Aisheng , Varka Bhadram , Wu Bo , Markus Schneider-Pargmann , Philipp Zabel Cc: linux-can@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=/HNzMsstKctC8PB7quDVBrjlyGwlmAE7o10zajY1uBc=; b=owEBbQGS/pANAwAKAQx0Zd/5kJGcAcsmYgBo0mW0Gx+8yDyXRsre2uTwIuFV1HyaNU3hCibGu YzD7uRHhYiJATMEAAEKAB0WIQSf+wzYr2eoX/wVbPMMdGXf+ZCRnAUCaNJltAAKCRAMdGXf+ZCR nDpOCACNx8p0eOZ/ZSGx6y09aqc6fPLNu3NASN1rngk+vgqGILeE8vCTmASoB/p0/4Ql8tsar/j a4iALcQtSJiE0Y2EjMpu0FhF6dkOD/XjxvwAaarBwTrGX1x9RsIO0SbjJlBO3Wy05E9PjxC1HNm sj9/OsaFZIrT1sZLT3HOJQfIRHvbExhSxKQTkMDUNkn5xkG2moeH18Cb/dsLaCj8N3uQX1rSXJt 86aAJzbFPPanoypvshetgMXHB0cNAtN2paQay1WH0QZ1z9jgj1+S8pwy6KOLgM/aSnHllvNsWpd Sm5b8XFkJmwRIQMSTTZQnNIkd0RsO0CsqOw7it8wP+NQsV8Q 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-can@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 c82ea6043d40..afbab6ca5833 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_device *dev, struct m_can_classdev *cdev = netdev_priv(dev); int err; + /* Avoid waking up the controller if the interface is down */ + if (!(dev->flags & IFF_UP)) + return 0; + err = m_can_clk_start(cdev); if (err) return err; -- 2.51.0