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 AC52D279355 for ; Mon, 29 Sep 2025 08:41:04 +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=1759135266; cv=none; b=QPGEJj/l+IqlaoGZIIzfePWb9MoOsqoYG4HqAM2klJxi6S3ycaiECkJaJs2Gy4oeUkT6Yf7mkD1Gw3M6wbfJLv0ps3SiUx9fvIxWppR/o7yaUXCOOET30vomwhB1pJVHewJaJEqFPxiY5q7nBYbuNGXes1kgoZ8p6Ekmaex/8Xk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759135266; c=relaxed/simple; bh=5tnChyATOAZ6OPBt2M66f923GtK0q6/Pk9o3HKF/uDQ=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Xj1f4yd2GQx0UipsSm6Cij3kqFnLzbiz3dVvOO2/cNKUYDzm+fOcZPb2ZbpX4HJHutJSu/4z/h6urZVErVBzUfJI8Y08zoiPzS/cwBer5+dRLJ7BngZTT3Fm32ZGxhQ2GLz1pknkmTUjPuEtW8inSb4KOo+iXDcuBeEy+2rvYtI= 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 1v39R0-0001cw-7U; Mon, 29 Sep 2025 10:40:38 +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 1v39Qy-0012zL-2L; Mon, 29 Sep 2025 10:40:36 +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 59B9747C3A8; Mon, 29 Sep 2025 08:40:36 +0000 (UTC) From: Marc Kleine-Budde Date: Mon, 29 Sep 2025 10:40:14 +0200 Subject: [PATCH v4 2/4] can: m_can: m_can_handle_state_errors(): fix CAN state transition to Error Active 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: <20250929-m_can-fix-state-handling-v4-2-682b49b49d9a@pengutronix.de> References: <20250929-m_can-fix-state-handling-v4-0-682b49b49d9a@pengutronix.de> In-Reply-To: <20250929-m_can-fix-state-handling-v4-0-682b49b49d9a@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=3833; i=mkl@pengutronix.de; h=from:subject:message-id; bh=5tnChyATOAZ6OPBt2M66f923GtK0q6/Pk9o3HKF/uDQ=; b=owEBbQGS/pANAwAKAQx0Zd/5kJGcAcsmYgBo2kX+k2VVrFS9bULjv9F8kMve/W4UP5TS0oGOe TY93GYesqyJATMEAAEKAB0WIQSf+wzYr2eoX/wVbPMMdGXf+ZCRnAUCaNpF/gAKCRAMdGXf+ZCR nE6qB/9XI/UYIYDSkuRnHODDMi7ZN2a0VTCHLE76nQbNV+Kx9p5FrdXcAjOMEhJ9tO7oy9jHJ78 CINSDV7F+VuwK4VkBS1JD3l5hvW305nyTrqeS4lZ08eKCEXMh2CiIOlGd07xMpDJ/lZMm3q+saK hVBg3CcsadLHempFYPFvfwQvxGvZuwO6+sCkm/zuQR+n6km4WgS9y5ixWwHuMsYkTV30iHSpf4l 4xHg8I+eRAzUR+q+FlzX6hVeiAWBO5/bl/P/NBtqeAglw7uhRmaOO6clJwAPDgl+ACwEgdWFTny RYHRAQ/TWuq3o74nISPOwuXO1JAh03x/cLf50XnDgTJCQPnP 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 The CAN Error State is determined by the receive and transmit error counters. The CAN error counters decrease when reception/transmission is successful, so that a status transition back to the Error Active status is possible. This transition is not handled by m_can_handle_state_errors(). Add the missing detection of the Error Active state to m_can_handle_state_errors() and extend the handling of this state in m_can_handle_state_change(). Fixes: e0d1f4816f2a ("can: m_can: add Bosch M_CAN controller support") Fixes: cd0d83eab2e0 ("can: m_can: m_can_handle_state_change(): fix state change") Reviewed-by: Markus Schneider-Pargmann Signed-off-by: Marc Kleine-Budde --- drivers/net/can/m_can/m_can.c | 55 ++++++++++++++++++++++++++----------------- 1 file changed, 33 insertions(+), 22 deletions(-) diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index fe74dbd2c966..4826b8dcad0f 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -812,6 +812,9 @@ static int m_can_handle_state_change(struct net_device *dev, u32 timestamp = 0; switch (new_state) { + case CAN_STATE_ERROR_ACTIVE: + cdev->can.state = CAN_STATE_ERROR_ACTIVE; + break; case CAN_STATE_ERROR_WARNING: /* error warning state */ cdev->can.can_stats.error_warning++; @@ -841,6 +844,12 @@ static int m_can_handle_state_change(struct net_device *dev, __m_can_get_berr_counter(dev, &bec); switch (new_state) { + case CAN_STATE_ERROR_ACTIVE: + cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT; + cf->data[1] = CAN_ERR_CRTL_ACTIVE; + cf->data[6] = bec.txerr; + cf->data[7] = bec.rxerr; + break; case CAN_STATE_ERROR_WARNING: /* error warning state */ cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT; @@ -877,30 +886,33 @@ static int m_can_handle_state_change(struct net_device *dev, return 1; } -static int m_can_handle_state_errors(struct net_device *dev, u32 psr) +static enum can_state +m_can_state_get_by_psr(struct m_can_classdev *cdev) +{ + u32 reg_psr; + + reg_psr = m_can_read(cdev, M_CAN_PSR); + + if (reg_psr & PSR_BO) + return CAN_STATE_BUS_OFF; + if (reg_psr & PSR_EP) + return CAN_STATE_ERROR_PASSIVE; + if (reg_psr & PSR_EW) + return CAN_STATE_ERROR_WARNING; + + return CAN_STATE_ERROR_ACTIVE; +} + +static int m_can_handle_state_errors(struct net_device *dev) { struct m_can_classdev *cdev = netdev_priv(dev); - int work_done = 0; + enum can_state new_state; - if (psr & PSR_EW && cdev->can.state != CAN_STATE_ERROR_WARNING) { - netdev_dbg(dev, "entered error warning state\n"); - work_done += m_can_handle_state_change(dev, - CAN_STATE_ERROR_WARNING); - } + new_state = m_can_state_get_by_psr(cdev); + if (new_state == cdev->can.state) + return 0; - if (psr & PSR_EP && cdev->can.state != CAN_STATE_ERROR_PASSIVE) { - netdev_dbg(dev, "entered error passive state\n"); - work_done += m_can_handle_state_change(dev, - CAN_STATE_ERROR_PASSIVE); - } - - if (psr & PSR_BO && cdev->can.state != CAN_STATE_BUS_OFF) { - netdev_dbg(dev, "entered error bus off state\n"); - work_done += m_can_handle_state_change(dev, - CAN_STATE_BUS_OFF); - } - - return work_done; + return m_can_handle_state_change(dev, new_state); } static void m_can_handle_other_err(struct net_device *dev, u32 irqstatus) @@ -1031,8 +1043,7 @@ static int m_can_rx_handler(struct net_device *dev, int quota, u32 irqstatus) } if (irqstatus & IR_ERR_STATE) - work_done += m_can_handle_state_errors(dev, - m_can_read(cdev, M_CAN_PSR)); + work_done += m_can_handle_state_errors(dev); if (irqstatus & IR_ERR_BUS_30X) work_done += m_can_handle_bus_errors(dev, irqstatus, -- 2.51.0