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 1ACD82C0F91 for ; Wed, 8 Oct 2025 19:08:08 +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=1759950491; cv=none; b=WG617r/B6MgOBs4GFhrloZpLAOzg78r4UaErbrvjj72/866o+NO44cvUXUVN877NBnemhygIYne9MMR2txrtil0U/HcOJUNdsNJbQnY5kiTNKmTI2U6wQHzaZn0jDeHAEC2sNBuHuF3QCAZyf/T6hkhxbR+u1+PxMmvsb/nJrhc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759950491; c=relaxed/simple; bh=pSIg4w43P6DHspql22I5oY6RYYzVHVSRk26zpHsOzzs=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=CV1/d7PHt2DaK4vqYMAw0tEdVWScRYVUhQMLTe40LUZRylTdGn38sC8xQwwcR20WoUr76GoC2Xlwy2mcfdhxxUPnqJic/kVYNcdKCLVqXG/+wRnDTha11iz4Ah5gATou2SL9fpSrHITGpWL2ld2DFOUuhnY3bq9k4z+Mr08B3bM= 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 1v6ZW4-0003RS-3P; Wed, 08 Oct 2025 21:08:00 +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 1v6ZW3-002cDO-1S; Wed, 08 Oct 2025 21:07:59 +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 1C3EE4821FB; Wed, 08 Oct 2025 19:07:59 +0000 (UTC) From: Marc Kleine-Budde Date: Wed, 08 Oct 2025 21:07:42 +0200 Subject: [PATCH 7/7] 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: <20251008-m_can-cleanups-v1-7-1784a18eaa84@pengutronix.de> References: <20251008-m_can-cleanups-v1-0-1784a18eaa84@pengutronix.de> In-Reply-To: <20251008-m_can-cleanups-v1-0-1784a18eaa84@pengutronix.de> To: Chandrasekar Ramakrishnan , Vincent Mailhol , Markus Schneider-Pargmann Cc: linux-can@vger.kernel.org, linux-kernel@vger.kernel.org, kernel@pengutronix.de, Marc Kleine-Budde X-Mailer: b4 0.15-dev-92513 X-Developer-Signature: v=1; a=openpgp-sha256; l=951; i=mkl@pengutronix.de; h=from:subject:message-id; bh=pSIg4w43P6DHspql22I5oY6RYYzVHVSRk26zpHsOzzs=; b=owEBbQGS/pANAwAKAQx0Zd/5kJGcAcsmYgBo5raMPX96GJKRD76fHRQ79PrAoU4fLmz4zBZXS NTytYnnMrKJATMEAAEKAB0WIQSf+wzYr2eoX/wVbPMMdGXf+ZCRnAUCaOa2jAAKCRAMdGXf+ZCR nHNiCACZv/pgKj5utZB5oUUW+J4a3g+ye8cwvOLN+eIomr7xKH8ur+N0oQHXJgxRnpySZM0FsYO YJz+1VA3ekASBxO5HEUo/PnZmryLchOjY7IMSOZOR0+q1YAwE7ym4CTzLAuzRofptfSqXtPHOaR JL3+16DWurdTpJhLJxsvV1HD+KkAOHn7IB1AhNyANY1dKF9Er6HQxazia6i3ZlQ9w4Ul0qhdoyp d4lIPVk7BWuU/c05IU8VXDTJ5RVKfFPOMRUgIArXnaUpErK1o0h6qySiI2wlItovn/IWe1tbXwK /fN5JUpyZYHcdVbR4a/Je5OFKxyWNOTZg8ECpceun9pE8DRr 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. Reviewed-by: Markus Schneider-Pargmann 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 4451ea750b74..0b622248e229 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