From patchwork Mon Jan 18 15:08:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 365935 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 44D54C433E6 for ; Mon, 18 Jan 2021 15:10:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 172FC22BF3 for ; Mon, 18 Jan 2021 15:10:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405432AbhARPKI (ORCPT ); Mon, 18 Jan 2021 10:10:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34340 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405408AbhARPJm (ORCPT ); Mon, 18 Jan 2021 10:09:42 -0500 Received: from laurent.telenet-ops.be (laurent.telenet-ops.be [IPv6:2a02:1800:110:4::f00:19]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5CF6CC061575 for ; Mon, 18 Jan 2021 07:09:01 -0800 (PST) Received: from ramsan.of.borg ([84.195.186.194]) by laurent.telenet-ops.be with bizsmtp id JF8z2400T4C55Sk01F8zQZ; Mon, 18 Jan 2021 16:08:59 +0100 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1l1W9L-004cql-1j; Mon, 18 Jan 2021 16:08:59 +0100 Received: from geert by rox.of.borg with local (Exim 4.93) (envelope-from ) id 1l1W9K-003LKg-LI; Mon, 18 Jan 2021 16:08:58 +0100 From: Geert Uytterhoeven To: Steve Glendinning , "David S . Miller" , Jakub Kicinski Cc: netdev@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH] net: smsc911x: Make Runtime PM handling more fine-grained Date: Mon, 18 Jan 2021 16:08:57 +0100 Message-Id: <20210118150857.796943-1-geert+renesas@glider.be> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Currently the smsc911x driver has mininal power management: during driver probe, the device is powered up, and during driver remove, it is powered down. Improve power management by making it more fine-grained: 1. Power the device down when driver probe is finished, 2. Power the device (down) when it is opened (closed), 3. Make sure the device is powered during PHY access. Signed-off-by: Geert Uytterhoeven --- Tested on r8a73a4/ape6evm, where the LAN9220 is connected to a power-managed bus, and any attempt to access a device register while the device is suspended will trigger an asynchronous external abort. --- drivers/net/ethernet/smsc/smsc911x.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/smsc/smsc911x.c b/drivers/net/ethernet/smsc/smsc911x.c index 823d9a7184fe6aa1..606c79de93a68146 100644 --- a/drivers/net/ethernet/smsc/smsc911x.c +++ b/drivers/net/ethernet/smsc/smsc911x.c @@ -557,6 +557,7 @@ static int smsc911x_mii_read(struct mii_bus *bus, int phyaddr, int regidx) unsigned int addr; int i, reg; + pm_runtime_get_sync(bus->parent); spin_lock_irqsave(&pdata->mac_lock, flags); /* Confirm MII not busy */ @@ -582,6 +583,7 @@ static int smsc911x_mii_read(struct mii_bus *bus, int phyaddr, int regidx) out: spin_unlock_irqrestore(&pdata->mac_lock, flags); + pm_runtime_put(bus->parent); return reg; } @@ -594,6 +596,7 @@ static int smsc911x_mii_write(struct mii_bus *bus, int phyaddr, int regidx, unsigned int addr; int i, reg; + pm_runtime_get_sync(bus->parent); spin_lock_irqsave(&pdata->mac_lock, flags); /* Confirm MII not busy */ @@ -623,6 +626,7 @@ static int smsc911x_mii_write(struct mii_bus *bus, int phyaddr, int regidx, out: spin_unlock_irqrestore(&pdata->mac_lock, flags); + pm_runtime_put(bus->parent); return reg; } @@ -1589,6 +1593,8 @@ static int smsc911x_open(struct net_device *dev) int retval; int irq_flags; + pm_runtime_get_sync(dev->dev.parent); + /* find and start the given phy */ if (!dev->phydev) { retval = smsc911x_mii_probe(dev); @@ -1735,6 +1741,7 @@ static int smsc911x_open(struct net_device *dev) phy_disconnect(dev->phydev); dev->phydev = NULL; out: + pm_runtime_put(dev->dev.parent); return retval; } @@ -1766,6 +1773,7 @@ static int smsc911x_stop(struct net_device *dev) dev->phydev = NULL; } netif_carrier_off(dev); + pm_runtime_put(dev->dev.parent); SMSC_TRACE(pdata, ifdown, "Interface stopped"); return 0; @@ -2334,7 +2342,6 @@ static int smsc911x_drv_remove(struct platform_device *pdev) free_netdev(dev); - pm_runtime_put(&pdev->dev); pm_runtime_disable(&pdev->dev); return 0; @@ -2540,6 +2547,7 @@ static int smsc911x_drv_probe(struct platform_device *pdev) } spin_unlock_irq(&pdata->mac_lock); + pm_runtime_put(&pdev->dev); netdev_info(dev, "MAC Address: %pM\n", dev->dev_addr);