From patchwork Fri May 5 13:50:33 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Quentin Schulz X-Patchwork-Id: 98636 Delivered-To: patch@linaro.org Received: by 10.140.96.100 with SMTP id j91csp133381qge; Fri, 5 May 2017 06:51:03 -0700 (PDT) X-Received: by 10.99.42.199 with SMTP id q190mr3385464pgq.13.1493992263361; Fri, 05 May 2017 06:51:03 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id b12si5826158plm.77.2017.05.05.06.51.03; Fri, 05 May 2017 06:51:03 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755090AbdEENut (ORCPT + 25 others); Fri, 5 May 2017 09:50:49 -0400 Received: from mail.free-electrons.com ([62.4.15.54]:59989 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753297AbdEENuo (ORCPT ); Fri, 5 May 2017 09:50:44 -0400 Received: by mail.free-electrons.com (Postfix, from userid 110) id ABC5720F67; Fri, 5 May 2017 15:50:42 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on mail.free-electrons.com X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,SHORTCIRCUIT shortcircuit=ham autolearn=disabled version=3.4.0 Received: from localhost.localdomain (LStLambert-657-1-97-87.w90-63.abo.wanadoo.fr [90.63.216.87]) by mail.free-electrons.com (Postfix) with ESMTPSA id 6B74520829; Fri, 5 May 2017 15:50:42 +0200 (CEST) From: Quentin Schulz To: wg@grandegger.com, mkl@pengutronix.de, mario.huettel@gmx.net, socketcan@hartkopp.net Cc: Quentin Schulz , linux-can@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, alexandre.belloni@free-electrons.com, thomas.petazzoni@free-electrons.com Subject: [PATCH v4 4/4] can: m_can: add deep Suspend/Resume support Date: Fri, 5 May 2017 15:50:33 +0200 Message-Id: <20170505135033.8349-4-quentin.schulz@free-electrons.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170505135033.8349-1-quentin.schulz@free-electrons.com> References: <20170505135033.8349-1-quentin.schulz@free-electrons.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This adds Power Management deep Suspend/Resume support for Bosch M_CAN chip. When entering deep sleep, the clocks are gated, the interrupts are disabled. When resuming from deep sleep, the chip needs to be reinitialized, the clocks ungated and the interrupts enabled. Signed-off-by: Quentin Schulz --- v4: - added a TODO comment for efficient runtime PM support, - used m_can_clk_start/stop functions added in v4 to have symmetric suspend and resume functions. v3: - do not close/reopen the can interface (which was previously done when calling m_can_close), basically do the same routine as in probe but it does not close/open the can device, - update commit log, v2: - fix erroneous commit log, drivers/net/can/m_can/m_can.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) -- 2.11.0 diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index 653b304d7091..f4947a74b65f 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -1668,6 +1668,8 @@ static int m_can_plat_probe(struct platform_device *pdev) return ret; } +/* TODO: runtime PM with power down or sleep mode */ + static __maybe_unused int m_can_suspend(struct device *dev) { struct net_device *ndev = dev_get_drvdata(dev); @@ -1676,10 +1678,10 @@ static __maybe_unused int m_can_suspend(struct device *dev) if (netif_running(ndev)) { netif_stop_queue(ndev); netif_device_detach(ndev); + m_can_stop(ndev); + m_can_clk_stop(priv); } - /* TODO: enter low power */ - priv->can.state = CAN_STATE_SLEEPING; return 0; @@ -1690,11 +1692,18 @@ static __maybe_unused int m_can_resume(struct device *dev) struct net_device *ndev = dev_get_drvdata(dev); struct m_can_priv *priv = netdev_priv(ndev); - /* TODO: exit low power */ + m_can_init_ram(priv); priv->can.state = CAN_STATE_ERROR_ACTIVE; if (netif_running(ndev)) { + int ret; + + ret = m_can_clk_start(priv); + if (ret) + return ret; + + m_can_start(ndev); netif_device_attach(ndev); netif_start_queue(ndev); }