From patchwork Wed Dec 18 12:10:27 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Kleine-Budde X-Patchwork-Id: 13913575 X-Patchwork-Delegate: kuba@kernel.org 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 0615019EEBD for ; Wed, 18 Dec 2024 12:17:28 +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=1734524252; cv=none; b=Dn+OVm/TchV5iL6DzFfpEve/dkbPZF60Jpar+yxMtboUSmmhix/7q0QhCrKFRhh0wRYy5ksvqFwFLMBOQhIOruejq28he91izosLcFlJ0OGgrMNPEigu0HhqKObQ8amqXgQ46IXIRJQAJvmnLktZNgq61Xu40E2Tlgh50wAW6Rg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734524252; c=relaxed/simple; bh=IpqxAPIsZx3w25GQdM2uw9JCEezPzauequ1qRCOnV4A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qtR3cJFvrB8LEAjJFk/x3hGHIL+/ONu5iGLaNlkmj1+dkaRbzfTy+zF2EdyMMeiRDhrvbLeOzQapbKkTenM8N0sJlsAacpcEm7cPCEnj9lpVBT+0INASYfR6+KkqegikBhiv0bC9CgpxHNu4mu6Fpoz1niyg1+hugauQj2uv97w= 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 1tNszX-0003VG-1p for netdev@vger.kernel.org; Wed, 18 Dec 2024 13:17:27 +0100 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 1tNszW-0041w6-02 for netdev@vger.kernel.org; Wed, 18 Dec 2024 13:17:26 +0100 Received: from dspam.blackshift.org (localhost [127.0.0.1]) by bjornoya.blackshift.org (Postfix) with SMTP id 762CA39168C for ; Wed, 18 Dec 2024 12:17:26 +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 64CC5391677; Wed, 18 Dec 2024 12:17:24 +0000 (UTC) Received: from blackshift.org (localhost [::1]) by hardanger.blackshift.org (OpenSMTPD) with ESMTP id ac31a6d3; Wed, 18 Dec 2024 12:17:23 +0000 (UTC) From: Marc Kleine-Budde To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, linux-can@vger.kernel.org, kernel@pengutronix.de, Matthias Schiffer , Markus Schneider-Pargmann , Marc Kleine-Budde Subject: [PATCH net 1/2] can: m_can: set init flag earlier in probe Date: Wed, 18 Dec 2024 13:10:27 +0100 Message-ID: <20241218121722.2311963-2-mkl@pengutronix.de> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20241218121722.2311963-1-mkl@pengutronix.de> References: <20241218121722.2311963-1-mkl@pengutronix.de> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 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: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Matthias Schiffer While an m_can controller usually already has the init flag from a hardware reset, no such reset happens on the integrated m_can_pci of the Intel Elkhart Lake. If the CAN controller is found in an active state, m_can_dev_setup() would fail because m_can_niso_supported() calls m_can_cccr_update_bits(), which refuses to modify any other configuration bits when CCCR_INIT is not set. To avoid this issue, set CCCR_INIT before attempting to modify any other configuration flags. Fixes: cd5a46ce6fa6 ("can: m_can: don't enable transceiver when probing") Signed-off-by: Matthias Schiffer Reviewed-by: Markus Schneider-Pargmann Link: https://patch.msgid.link/e247f331cb72829fcbdfda74f31a59cbad1a6006.1728288535.git.matthias.schiffer@ew.tq-group.com Signed-off-by: Marc Kleine-Budde --- drivers/net/can/m_can/m_can.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) base-commit: 954a2b40719a21e763a1bba2f0da92347e058fce diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index 533bcb77c9f9..67c404fbe166 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -1695,6 +1695,14 @@ static int m_can_dev_setup(struct m_can_classdev *cdev) return -EINVAL; } + /* Write the INIT bit, in case no hardware reset has happened before + * the probe (for example, it was observed that the Intel Elkhart Lake + * SoCs do not properly reset the CAN controllers on reboot) + */ + err = m_can_cccr_update_bits(cdev, CCCR_INIT, CCCR_INIT); + if (err) + return err; + if (!cdev->is_peripheral) netif_napi_add(dev, &cdev->napi, m_can_poll); @@ -1746,11 +1754,7 @@ static int m_can_dev_setup(struct m_can_classdev *cdev) return -EINVAL; } - /* Forcing standby mode should be redundant, as the chip should be in - * standby after a reset. Write the INIT bit anyways, should the chip - * be configured by previous stage. - */ - return m_can_cccr_update_bits(cdev, CCCR_INIT, CCCR_INIT); + return 0; } static void m_can_stop(struct net_device *dev)