From patchwork Tue May 3 13:15:01 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 12835778 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 274A3C433EF for ; Tue, 3 May 2022 13:18:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235906AbiECNWM (ORCPT ); Tue, 3 May 2022 09:22:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43104 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235861AbiECNWG (ORCPT ); Tue, 3 May 2022 09:22:06 -0400 Received: from mailout3.hostsharing.net (mailout3.hostsharing.net [IPv6:2a01:4f8:150:2161:1:b009:f236:0]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F36032EFB; Tue, 3 May 2022 06:18:27 -0700 (PDT) Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (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-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "*.hostsharing.net", Issuer "RapidSSL TLS DV RSA Mixed SHA256 2020 CA-1" (verified OK)) by mailout3.hostsharing.net (Postfix) with ESMTPS id DBA87101E689E; Tue, 3 May 2022 15:18:25 +0200 (CEST) Received: from localhost (unknown [89.246.108.87]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id A11DB630FA12; Tue, 3 May 2022 15:18:25 +0200 (CEST) X-Mailbox-Line: From d921168f4838d5d033679452749d5e00b2672bac Mon Sep 17 00:00:00 2001 Message-Id: In-Reply-To: References: From: Lukas Wunner Date: Tue, 3 May 2022 15:15:01 +0200 Subject: [PATCH net-next v2 1/7] usbnet: Run unregister_netdev() before unbind() again To: "David S. Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-usb@vger.kernel.org, Steve Glendinning , UNGLinuxDriver@microchip.com, Oliver Neukum , Andre Edich , Oleksij Rempel , Martyn Welch , Gabriel Hojda , Christoph Fritz , Lino Sanfilippo , Philipp Rosenberger , Heiner Kallweit , Andrew Lunn , Russell King , Ferry Toth Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Commit 2c9d6c2b871d ("usbnet: run unbind() before unregister_netdev()") sought to fix a use-after-free on disconnect of USB Ethernet adapters. It turns out that a different fix is necessary to address the issue: https://lore.kernel.org/netdev/18b3541e5372bc9b9fc733d422f4e698c089077c.1650177997.git.lukas@wunner.de/ So the commit was not necessary. The commit made binding and unbinding of USB Ethernet asymmetrical: Before, usbnet_probe() first invoked the ->bind() callback and then register_netdev(). usbnet_disconnect() mirrored that by first invoking unregister_netdev() and then ->unbind(). Since the commit, the order in usbnet_disconnect() is reversed and no longer mirrors usbnet_probe(). One consequence is that a PHY disconnected (and stopped) in ->unbind() is afterwards stopped once more by unregister_netdev() as it closes the netdev before unregistering. That necessitates a contortion in ->stop() because the PHY may only be stopped if it hasn't already been disconnected. Reverting the commit allows making the call to phy_stop() unconditional in ->stop(). Tested-by: Oleksij Rempel # LAN9514/9512/9500 Tested-by: Ferry Toth # LAN9514 Signed-off-by: Lukas Wunner Acked-by: Oliver Neukum Cc: Martyn Welch Cc: Andrew Lunn --- drivers/net/usb/asix_devices.c | 6 +----- drivers/net/usb/smsc95xx.c | 3 +-- drivers/net/usb/usbnet.c | 6 +++--- 3 files changed, 5 insertions(+), 10 deletions(-) diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c index 38e47a93fb83..5b5eb630c4b7 100644 --- a/drivers/net/usb/asix_devices.c +++ b/drivers/net/usb/asix_devices.c @@ -795,11 +795,7 @@ static int ax88772_stop(struct usbnet *dev) { struct asix_common_private *priv = dev->driver_priv; - /* On unplugged USB, we will get MDIO communication errors and the - * PHY will be set in to PHY_HALTED state. - */ - if (priv->phydev->state != PHY_HALTED) - phy_stop(priv->phydev); + phy_stop(priv->phydev); return 0; } diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c index 4ef61f6b85df..edf0492ad489 100644 --- a/drivers/net/usb/smsc95xx.c +++ b/drivers/net/usb/smsc95xx.c @@ -1243,8 +1243,7 @@ static int smsc95xx_start_phy(struct usbnet *dev) static int smsc95xx_stop(struct usbnet *dev) { - if (dev->net->phydev) - phy_stop(dev->net->phydev); + phy_stop(dev->net->phydev); return 0; } diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index 9a6450f796dc..36b24ec11650 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -1616,9 +1616,6 @@ void usbnet_disconnect (struct usb_interface *intf) xdev->bus->bus_name, xdev->devpath, dev->driver_info->description); - if (dev->driver_info->unbind) - dev->driver_info->unbind(dev, intf); - net = dev->net; unregister_netdev (net); @@ -1626,6 +1623,9 @@ void usbnet_disconnect (struct usb_interface *intf) usb_scuttle_anchored_urbs(&dev->deferred); + if (dev->driver_info->unbind) + dev->driver_info->unbind(dev, intf); + usb_kill_urb(dev->interrupt); usb_free_urb(dev->interrupt); kfree(dev->padding_pkt); From patchwork Tue May 3 13:15:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 12835779 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA41CC433F5 for ; Tue, 3 May 2022 13:21:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236026AbiECNYh (ORCPT ); Tue, 3 May 2022 09:24:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45354 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236012AbiECNYg (ORCPT ); Tue, 3 May 2022 09:24:36 -0400 Received: from mailout1.hostsharing.net (mailout1.hostsharing.net [IPv6:2a01:37:1000::53df:5fcc:0]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B836F36B47; Tue, 3 May 2022 06:21:03 -0700 (PDT) Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (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-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "*.hostsharing.net", Issuer "RapidSSL TLS DV RSA Mixed SHA256 2020 CA-1" (verified OK)) by mailout1.hostsharing.net (Postfix) with ESMTPS id D586C101920F1; Tue, 3 May 2022 15:21:01 +0200 (CEST) Received: from localhost (unknown [89.246.108.87]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id B3CA6630FA12; Tue, 3 May 2022 15:21:01 +0200 (CEST) X-Mailbox-Line: From 78fd68df1b27f187910a3bca538ae293baa14ab2 Mon Sep 17 00:00:00 2001 Message-Id: <78fd68df1b27f187910a3bca538ae293baa14ab2.1651574194.git.lukas@wunner.de> In-Reply-To: References: From: Lukas Wunner Date: Tue, 3 May 2022 15:15:02 +0200 Subject: [PATCH net-next v2 2/7] usbnet: smsc95xx: Don't clear read-only PHY interrupt To: "David S. Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-usb@vger.kernel.org, Steve Glendinning , UNGLinuxDriver@microchip.com, Oliver Neukum , Andre Edich , Oleksij Rempel , Martyn Welch , Gabriel Hojda , Christoph Fritz , Lino Sanfilippo , Philipp Rosenberger , Heiner Kallweit , Andrew Lunn , Russell King , Ferry Toth Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Upon receiving data from the Interrupt Endpoint, the SMSC LAN95xx driver attempts to clear the signaled interrupts by writing "all ones" to the Interrupt Status Register. However the driver only ever enables a single type of interrupt, namely the PHY Interrupt. And according to page 119 of the LAN950x datasheet, its bit in the Interrupt Status Register is read-only. There's no other way to clear it than in a separate PHY register: https://www.microchip.com/content/dam/mchp/documents/UNG/ProductDocuments/DataSheets/LAN950x-Data-Sheet-DS00001875D.pdf Consequently, writing "all ones" to the Interrupt Status Register is pointless and can be dropped. Tested-by: Oleksij Rempel # LAN9514/9512/9500 Tested-by: Ferry Toth # LAN9514 Signed-off-by: Lukas Wunner Reviewed-by: Andrew Lunn --- drivers/net/usb/smsc95xx.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c index edf0492ad489..2cb44d65bbc3 100644 --- a/drivers/net/usb/smsc95xx.c +++ b/drivers/net/usb/smsc95xx.c @@ -572,10 +572,6 @@ static int smsc95xx_link_reset(struct usbnet *dev) unsigned long flags; int ret; - ret = smsc95xx_write_reg(dev, INT_STS, INT_STS_CLEAR_ALL_); - if (ret < 0) - return ret; - spin_lock_irqsave(&pdata->mac_cr_lock, flags); if (pdata->phydev->duplex != DUPLEX_FULL) { pdata->mac_cr &= ~MAC_CR_FDPX_; From patchwork Tue May 3 13:15:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 12835784 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 688F3C433F5 for ; Tue, 3 May 2022 13:22:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236092AbiECN0E (ORCPT ); Tue, 3 May 2022 09:26:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46406 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236091AbiECN0D (ORCPT ); Tue, 3 May 2022 09:26:03 -0400 Received: from mailout1.hostsharing.net (mailout1.hostsharing.net [83.223.95.204]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7A91D36B7C; Tue, 3 May 2022 06:22:30 -0700 (PDT) Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (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-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "*.hostsharing.net", Issuer "RapidSSL TLS DV RSA Mixed SHA256 2020 CA-1" (verified OK)) by mailout1.hostsharing.net (Postfix) with ESMTPS id 0352C101917A2; Tue, 3 May 2022 15:22:29 +0200 (CEST) Received: from localhost (unknown [89.246.108.87]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id D52C9630FA12; Tue, 3 May 2022 15:22:28 +0200 (CEST) X-Mailbox-Line: From f78b5f725fe75265f884ef0b35389fd45cd81471 Mon Sep 17 00:00:00 2001 Message-Id: In-Reply-To: References: From: Lukas Wunner Date: Tue, 3 May 2022 15:15:03 +0200 Subject: [PATCH net-next v2 3/7] usbnet: smsc95xx: Don't reset PHY behind PHY driver's back To: "David S. Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-usb@vger.kernel.org, Steve Glendinning , UNGLinuxDriver@microchip.com, Oliver Neukum , Andre Edich , Oleksij Rempel , Martyn Welch , Gabriel Hojda , Christoph Fritz , Lino Sanfilippo , Philipp Rosenberger , Heiner Kallweit , Andrew Lunn , Russell King , Ferry Toth Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org smsc95xx_reset() resets the PHY behind the PHY driver's back, which seems like a bad idea generally. Remove that portion of the function. We're about to use PHY interrupts instead of polling to detect link changes on SMSC LAN95xx chips. Because smsc95xx_reset() is called from usbnet_open(), PHY interrupt settings are lost whenever the net_device is brought up. There are two other callers of smsc95xx_reset(), namely smsc95xx_bind() and smsc95xx_reset_resume(), and both may indeed benefit from a PHY reset. However they already perform one through their calls to phy_connect_direct() and phy_init_hw(). Tested-by: Oleksij Rempel # LAN9514/9512/9500 Tested-by: Ferry Toth # LAN9514 Signed-off-by: Lukas Wunner Cc: Martyn Welch Cc: Gabriel Hojda Reviewed-by: Andrew Lunn --- drivers/net/usb/smsc95xx.c | 18 ------------------ 1 file changed, 18 deletions(-) diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c index 2cb44d65bbc3..6c37c7adde1b 100644 --- a/drivers/net/usb/smsc95xx.c +++ b/drivers/net/usb/smsc95xx.c @@ -887,24 +887,6 @@ static int smsc95xx_reset(struct usbnet *dev) return ret; } - ret = smsc95xx_write_reg(dev, PM_CTRL, PM_CTL_PHY_RST_); - if (ret < 0) - return ret; - - timeout = 0; - do { - msleep(10); - ret = smsc95xx_read_reg(dev, PM_CTRL, &read_buf); - if (ret < 0) - return ret; - timeout++; - } while ((read_buf & PM_CTL_PHY_RST_) && (timeout < 100)); - - if (timeout >= 100) { - netdev_warn(dev->net, "timeout waiting for PHY Reset\n"); - return ret; - } - ret = smsc95xx_set_mac_address(dev); if (ret < 0) return ret; From patchwork Tue May 3 13:15:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 12835785 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EA4A5C433F5 for ; Tue, 3 May 2022 13:23:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236035AbiECN1B (ORCPT ); Tue, 3 May 2022 09:27:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47360 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236016AbiECN07 (ORCPT ); Tue, 3 May 2022 09:26:59 -0400 Received: from mailout2.hostsharing.net (mailout2.hostsharing.net [IPv6:2a01:37:3000::53df:4ee9:0]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3640336E02 for ; Tue, 3 May 2022 06:23:26 -0700 (PDT) Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (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-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "*.hostsharing.net", Issuer "RapidSSL TLS DV RSA Mixed SHA256 2020 CA-1" (verified OK)) by mailout2.hostsharing.net (Postfix) with ESMTPS id 8207010171323; Tue, 3 May 2022 15:23:21 +0200 (CEST) Received: from localhost (unknown [89.246.108.87]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id 61726630FA12; Tue, 3 May 2022 15:23:21 +0200 (CEST) X-Mailbox-Line: From e6117cf857bea9af718d8c92d9d553c8f3a35e0a Mon Sep 17 00:00:00 2001 Message-Id: In-Reply-To: References: From: Lukas Wunner Date: Tue, 3 May 2022 15:15:04 +0200 Subject: [PATCH net-next v2 4/7] usbnet: smsc95xx: Avoid link settings race on interrupt reception To: "David S. Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-usb@vger.kernel.org, Steve Glendinning , UNGLinuxDriver@microchip.com, Oliver Neukum , Andre Edich , Oleksij Rempel , Martyn Welch , Gabriel Hojda , Christoph Fritz , Lino Sanfilippo , Philipp Rosenberger , Heiner Kallweit , Andrew Lunn , Russell King , Ferry Toth Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org When a PHY interrupt is signaled, the SMSC LAN95xx driver updates the MAC full duplex mode and PHY flow control registers based on cached data in struct phy_device: smsc95xx_status() # raises EVENT_LINK_RESET usbnet_deferred_kevent() smsc95xx_link_reset() # uses cached data in phydev Simultaneously, phylib polls link status once per second and updates that cached data: phy_state_machine() phy_check_link_status() phy_read_status() lan87xx_read_status() genphy_read_status() # updates cached data in phydev If smsc95xx_link_reset() wins the race against genphy_read_status(), the registers may be updated based on stale data. E.g. if the link was previously down, phydev->duplex is set to DUPLEX_UNKNOWN and that's what smsc95xx_link_reset() will use, even though genphy_read_status() may update it to DUPLEX_FULL afterwards. PHY interrupts are currently only enabled on suspend to trigger wakeup, so the impact of the race is limited, but we're about to enable them perpetually. Avoid the race by delaying execution of smsc95xx_link_reset() until phy_state_machine() has done its job and calls back via smsc95xx_handle_link_change(). Signaling EVENT_LINK_RESET on wakeup is not necessary because phylib picks up link status changes through polling. So drop the declaration of a ->link_reset() callback. Note that the semicolon on a line by itself added in smsc95xx_status() is a placeholder for a function call which will be added in a subsequent commit. That function call will actually handle the INT_ENP_PHY_INT_ interrupt. Tested-by: Oleksij Rempel # LAN9514/9512/9500 Tested-by: Ferry Toth # LAN9514 Signed-off-by: Lukas Wunner Reviewed-by: Andrew Lunn --- Changes since v1: * Silence "Error updating MAC full duplex mode" warning if it's caused by hot-removal. (Oleksij Rempel) * Explain in commit message why a semicolon on a line by itself is temporarily added in smsc95xx_status(). (Andrew Lunn) drivers/net/usb/smsc95xx.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c index 6c37c7adde1b..6309ff8e75de 100644 --- a/drivers/net/usb/smsc95xx.c +++ b/drivers/net/usb/smsc95xx.c @@ -566,7 +566,7 @@ static int smsc95xx_phy_update_flowcontrol(struct usbnet *dev) return smsc95xx_write_reg(dev, AFC_CFG, afc_cfg); } -static int smsc95xx_link_reset(struct usbnet *dev) +static void smsc95xx_mac_update_fullduplex(struct usbnet *dev) { struct smsc95xx_priv *pdata = dev->driver_priv; unsigned long flags; @@ -583,14 +583,16 @@ static int smsc95xx_link_reset(struct usbnet *dev) spin_unlock_irqrestore(&pdata->mac_cr_lock, flags); ret = smsc95xx_write_reg(dev, MAC_CR, pdata->mac_cr); - if (ret < 0) - return ret; + if (ret < 0) { + if (ret != -ENODEV) + netdev_warn(dev->net, + "Error updating MAC full duplex mode\n"); + return; + } ret = smsc95xx_phy_update_flowcontrol(dev); if (ret < 0) netdev_warn(dev->net, "Error updating PHY flow control\n"); - - return ret; } static void smsc95xx_status(struct usbnet *dev, struct urb *urb) @@ -607,7 +609,7 @@ static void smsc95xx_status(struct usbnet *dev, struct urb *urb) netif_dbg(dev, link, dev->net, "intdata: 0x%08X\n", intdata); if (intdata & INT_ENP_PHY_INT_) - usbnet_defer_kevent(dev, EVENT_LINK_RESET); + ; else netdev_warn(dev->net, "unexpected interrupt, intdata=0x%08X\n", intdata); @@ -1070,6 +1072,7 @@ static void smsc95xx_handle_link_change(struct net_device *net) struct usbnet *dev = netdev_priv(net); phy_print_status(net->phydev); + smsc95xx_mac_update_fullduplex(dev); usbnet_defer_kevent(dev, EVENT_LINK_CHANGE); } @@ -1975,7 +1978,6 @@ static const struct driver_info smsc95xx_info = { .description = "smsc95xx USB 2.0 Ethernet", .bind = smsc95xx_bind, .unbind = smsc95xx_unbind, - .link_reset = smsc95xx_link_reset, .reset = smsc95xx_reset, .check_connect = smsc95xx_start_phy, .stop = smsc95xx_stop, From patchwork Tue May 3 13:15:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 12835786 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A7D17C433EF for ; Tue, 3 May 2022 13:25:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236124AbiECN2p (ORCPT ); Tue, 3 May 2022 09:28:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47946 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236058AbiECN2G (ORCPT ); Tue, 3 May 2022 09:28:06 -0400 Received: from mailout3.hostsharing.net (mailout3.hostsharing.net [176.9.242.54]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A4CC037A0E; Tue, 3 May 2022 06:24:33 -0700 (PDT) Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (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-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "*.hostsharing.net", Issuer "RapidSSL TLS DV RSA Mixed SHA256 2020 CA-1" (verified OK)) by mailout3.hostsharing.net (Postfix) with ESMTPS id AC55D1002A096; Tue, 3 May 2022 15:24:31 +0200 (CEST) Received: from localhost (unknown [89.246.108.87]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id 75F8F630FA12; Tue, 3 May 2022 15:24:31 +0200 (CEST) X-Mailbox-Line: From c6b7f4e4a17913d2f2bc4fe722df0804c2d6fea7 Mon Sep 17 00:00:00 2001 Message-Id: In-Reply-To: References: From: Lukas Wunner Date: Tue, 3 May 2022 15:15:05 +0200 Subject: [PATCH net-next v2 5/7] usbnet: smsc95xx: Forward PHY interrupts to PHY driver to avoid polling To: "David S. Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-usb@vger.kernel.org, Steve Glendinning , UNGLinuxDriver@microchip.com, Oliver Neukum , Andre Edich , Oleksij Rempel , Martyn Welch , Gabriel Hojda , Christoph Fritz , Lino Sanfilippo , Philipp Rosenberger , Heiner Kallweit , Andrew Lunn , Russell King , Ferry Toth Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Link status of SMSC LAN95xx chips is polled once per second, even though they're capable of signaling PHY interrupts through the MAC layer. Forward those interrupts to the PHY driver to avoid polling. Benefits are reduced bus traffic, reduced CPU overhead and quicker interface bringup. Polling was introduced in 2016 by commit d69d16949346 ("usbnet: smsc95xx: fix link detection for disabled autonegotiation"). Back then, the LAN95xx driver neglected to enable the ENERGYON interrupt, hence couldn't detect link-up events when auto-negotiation was disabled. The proper solution would have been to enable the ENERGYON interrupt instead of polling. Since then, PHY handling was moved from the LAN95xx driver to the SMSC PHY driver with commit 05b35e7eb9a1 ("smsc95xx: add phylib support"). That PHY driver is capable of link detection with auto-negotiation disabled because it enables the ENERGYON interrupt. Note that signaling interrupts through the MAC layer not only works with the integrated PHY, but also with an external PHY, provided its interrupt pin is attached to LAN95xx's nPHY_INT pin. In the unlikely event that the interrupt pin of an external PHY is attached to a GPIO of the SoC (or not connected at all), the driver can be amended to retrieve the irq from the PHY's of_node. To forward PHY interrupts to phylib, it is not sufficient to call phy_mac_interrupt(). Instead, the PHY's interrupt handler needs to run so that PHY interrupts are cleared. That's because according to page 119 of the LAN950x datasheet, "The source of this interrupt is a level. The interrupt persists until it is cleared in the PHY." https://www.microchip.com/content/dam/mchp/documents/UNG/ProductDocuments/DataSheets/LAN950x-Data-Sheet-DS00001875D.pdf Therefore, create an IRQ domain with a single IRQ for the PHY. In the future, the IRQ domain may be extended to support the 11 GPIOs on the LAN95xx. Normally the PHY interrupt should be masked until the PHY driver has cleared it. However masking requires a (sleeping) USB transaction and interrupts are received in (non-sleepable) softirq context. I decided not to mask the interrupt at all (by using the dummy_irq_chip's noop ->irq_mask() callback): The USB interrupt endpoint is polled in 1 msec intervals and normally that's sufficient to wake the PHY driver's IRQ thread and have it clear the interrupt. If it does take longer, worst thing that can happen is the IRQ thread is woken again. No big deal. Because PHY interrupts are now perpetually enabled, there's no need to selectively enable them on suspend. So remove all invocations of smsc95xx_enable_phy_wakeup_interrupts(). In smsc95xx_resume(), move the call of phy_init_hw() before usbnet_resume() (which restarts the status URB) to ensure that the PHY is fully initialized when an interrupt is handled. Tested-by: Oleksij Rempel # LAN9514/9512/9500 Tested-by: Ferry Toth # LAN9514 Signed-off-by: Lukas Wunner Reviewed-by: Andrew Lunn # from a PHY perspective Cc: Andre Edich --- Changes since v1: * Eliminate a checkpatch "no space before tabs" warning. * Explain in commit message why the call to phy_init_hw() is moved in smsc95xx_resume(). drivers/net/usb/smsc95xx.c | 118 +++++++++++++++++++++---------------- 1 file changed, 66 insertions(+), 52 deletions(-) diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c index 6309ff8e75de..9278d4e24d79 100644 --- a/drivers/net/usb/smsc95xx.c +++ b/drivers/net/usb/smsc95xx.c @@ -18,6 +18,8 @@ #include #include #include +#include +#include #include #include #include @@ -53,6 +55,9 @@ #define SUSPEND_ALLMODES (SUSPEND_SUSPEND0 | SUSPEND_SUSPEND1 | \ SUSPEND_SUSPEND2 | SUSPEND_SUSPEND3) +#define SMSC95XX_NR_IRQS (1) /* raise to 12 for GPIOs */ +#define PHY_HWIRQ (SMSC95XX_NR_IRQS - 1) + struct smsc95xx_priv { u32 mac_cr; u32 hash_hi; @@ -61,6 +66,9 @@ struct smsc95xx_priv { spinlock_t mac_cr_lock; u8 features; u8 suspend_flags; + struct irq_chip irqchip; + struct irq_domain *irqdomain; + struct fwnode_handle *irqfwnode; struct mii_bus *mdiobus; struct phy_device *phydev; }; @@ -597,6 +605,8 @@ static void smsc95xx_mac_update_fullduplex(struct usbnet *dev) static void smsc95xx_status(struct usbnet *dev, struct urb *urb) { + struct smsc95xx_priv *pdata = dev->driver_priv; + unsigned long flags; u32 intdata; if (urb->actual_length != 4) { @@ -608,11 +618,20 @@ static void smsc95xx_status(struct usbnet *dev, struct urb *urb) intdata = get_unaligned_le32(urb->transfer_buffer); netif_dbg(dev, link, dev->net, "intdata: 0x%08X\n", intdata); + /* USB interrupts are received in softirq (tasklet) context. + * Switch to hardirq context to make genirq code happy. + */ + local_irq_save(flags); + __irq_enter_raw(); + if (intdata & INT_ENP_PHY_INT_) - ; + generic_handle_domain_irq(pdata->irqdomain, PHY_HWIRQ); else netdev_warn(dev->net, "unexpected interrupt, intdata=0x%08X\n", intdata); + + __irq_exit_raw(); + local_irq_restore(flags); } /* Enable or disable Tx & Rx checksum offload engines */ @@ -1080,8 +1099,9 @@ static int smsc95xx_bind(struct usbnet *dev, struct usb_interface *intf) { struct smsc95xx_priv *pdata; bool is_internal_phy; + char usb_path[64]; + int ret, phy_irq; u32 val; - int ret; printk(KERN_INFO SMSC_CHIPNAME " v" SMSC_DRIVER_VERSION "\n"); @@ -1121,10 +1141,38 @@ static int smsc95xx_bind(struct usbnet *dev, struct usb_interface *intf) if (ret) goto free_pdata; + /* create irq domain for use by PHY driver and GPIO consumers */ + usb_make_path(dev->udev, usb_path, sizeof(usb_path)); + pdata->irqfwnode = irq_domain_alloc_named_fwnode(usb_path); + if (!pdata->irqfwnode) { + ret = -ENOMEM; + goto free_pdata; + } + + pdata->irqdomain = irq_domain_create_linear(pdata->irqfwnode, + SMSC95XX_NR_IRQS, + &irq_domain_simple_ops, + pdata); + if (!pdata->irqdomain) { + ret = -ENOMEM; + goto free_irqfwnode; + } + + phy_irq = irq_create_mapping(pdata->irqdomain, PHY_HWIRQ); + if (!phy_irq) { + ret = -ENOENT; + goto remove_irqdomain; + } + + pdata->irqchip = dummy_irq_chip; + pdata->irqchip.name = SMSC_CHIPNAME; + irq_set_chip_and_handler_name(phy_irq, &pdata->irqchip, + handle_simple_irq, "phy"); + pdata->mdiobus = mdiobus_alloc(); if (!pdata->mdiobus) { ret = -ENOMEM; - goto free_pdata; + goto dispose_irq; } ret = smsc95xx_read_reg(dev, HW_CFG, &val); @@ -1157,6 +1205,7 @@ static int smsc95xx_bind(struct usbnet *dev, struct usb_interface *intf) goto unregister_mdio; } + pdata->phydev->irq = phy_irq; pdata->phydev->is_internal = is_internal_phy; /* detect device revision as different features may be available */ @@ -1199,6 +1248,15 @@ static int smsc95xx_bind(struct usbnet *dev, struct usb_interface *intf) free_mdio: mdiobus_free(pdata->mdiobus); +dispose_irq: + irq_dispose_mapping(phy_irq); + +remove_irqdomain: + irq_domain_remove(pdata->irqdomain); + +free_irqfwnode: + irq_domain_free_fwnode(pdata->irqfwnode); + free_pdata: kfree(pdata); return ret; @@ -1211,6 +1269,9 @@ static void smsc95xx_unbind(struct usbnet *dev, struct usb_interface *intf) phy_disconnect(dev->net->phydev); mdiobus_unregister(pdata->mdiobus); mdiobus_free(pdata->mdiobus); + irq_dispose_mapping(irq_find_mapping(pdata->irqdomain, PHY_HWIRQ)); + irq_domain_remove(pdata->irqdomain); + irq_domain_free_fwnode(pdata->irqfwnode); netif_dbg(dev, ifdown, dev->net, "free pdata\n"); kfree(pdata); } @@ -1235,29 +1296,6 @@ static u32 smsc_crc(const u8 *buffer, size_t len, int filter) return crc << ((filter % 2) * 16); } -static int smsc95xx_enable_phy_wakeup_interrupts(struct usbnet *dev, u16 mask) -{ - int ret; - - netdev_dbg(dev->net, "enabling PHY wakeup interrupts\n"); - - /* read to clear */ - ret = smsc95xx_mdio_read_nopm(dev, PHY_INT_SRC); - if (ret < 0) - return ret; - - /* enable interrupt source */ - ret = smsc95xx_mdio_read_nopm(dev, PHY_INT_MASK); - if (ret < 0) - return ret; - - ret |= mask; - - smsc95xx_mdio_write_nopm(dev, PHY_INT_MASK, ret); - - return 0; -} - static int smsc95xx_link_ok_nopm(struct usbnet *dev) { int ret; @@ -1424,7 +1462,6 @@ static int smsc95xx_enter_suspend3(struct usbnet *dev) static int smsc95xx_autosuspend(struct usbnet *dev, u32 link_up) { struct smsc95xx_priv *pdata = dev->driver_priv; - int ret; if (!netif_running(dev->net)) { /* interface is ifconfig down so fully power down hw */ @@ -1443,27 +1480,10 @@ static int smsc95xx_autosuspend(struct usbnet *dev, u32 link_up) } netdev_dbg(dev->net, "autosuspend entering SUSPEND1\n"); - - /* enable PHY wakeup events for if cable is attached */ - ret = smsc95xx_enable_phy_wakeup_interrupts(dev, - PHY_INT_MASK_ANEG_COMP_); - if (ret < 0) { - netdev_warn(dev->net, "error enabling PHY wakeup ints\n"); - return ret; - } - netdev_info(dev->net, "entering SUSPEND1 mode\n"); return smsc95xx_enter_suspend1(dev); } - /* enable PHY wakeup events so we remote wakeup if cable is pulled */ - ret = smsc95xx_enable_phy_wakeup_interrupts(dev, - PHY_INT_MASK_LINK_DOWN_); - if (ret < 0) { - netdev_warn(dev->net, "error enabling PHY wakeup ints\n"); - return ret; - } - netdev_dbg(dev->net, "autosuspend entering SUSPEND3\n"); return smsc95xx_enter_suspend3(dev); } @@ -1529,13 +1549,6 @@ static int smsc95xx_suspend(struct usb_interface *intf, pm_message_t message) } if (pdata->wolopts & WAKE_PHY) { - ret = smsc95xx_enable_phy_wakeup_interrupts(dev, - (PHY_INT_MASK_ANEG_COMP_ | PHY_INT_MASK_LINK_DOWN_)); - if (ret < 0) { - netdev_warn(dev->net, "error enabling PHY wakeup ints\n"); - goto done; - } - /* if link is down then configure EDPD and enter SUSPEND1, * otherwise enter SUSPEND0 below */ @@ -1769,11 +1782,12 @@ static int smsc95xx_resume(struct usb_interface *intf) return ret; } + phy_init_hw(pdata->phydev); + ret = usbnet_resume(intf); if (ret < 0) netdev_warn(dev->net, "usbnet_resume error\n"); - phy_init_hw(pdata->phydev); return ret; } From patchwork Tue May 3 13:15:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 12835805 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9829BC433EF for ; Tue, 3 May 2022 13:26:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236102AbiECNaP (ORCPT ); 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Tue, 3 May 2022 15:26:10 +0200 (CEST) X-Mailbox-Line: From e4a5d784e47bf919873e520e0c6c5156a1ecdde7 Mon Sep 17 00:00:00 2001 Message-Id: In-Reply-To: References: From: Lukas Wunner Date: Tue, 3 May 2022 15:15:06 +0200 Subject: [PATCH net-next v2 6/7] net: phy: smsc: Cache interrupt mask To: "David S. Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-usb@vger.kernel.org, Steve Glendinning , UNGLinuxDriver@microchip.com, Oliver Neukum , Andre Edich , Oleksij Rempel , Martyn Welch , Gabriel Hojda , Christoph Fritz , Lino Sanfilippo , Philipp Rosenberger , Heiner Kallweit , Andrew Lunn , Russell King , Ferry Toth Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Cache the interrupt mask to avoid re-reading it from the PHY upon every interrupt. This will simplify a subsequent commit which detects hot-removal in the interrupt handler and bails out. Analyzing and debugging PHY transactions also becomes simpler if such redundant reads are avoided. Last not least, interrupt overhead and latency is slightly improved. Tested-by: Oleksij Rempel # LAN9514/9512/9500 Tested-by: Ferry Toth # LAN9514 Signed-off-by: Lukas Wunner Reviewed-by: Andrew Lunn --- Changes since v1: * Expand commit message to explain in greater detail why caching the interrupt mask is beneficial. (Andrew Lunn) drivers/net/phy/smsc.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/drivers/net/phy/smsc.c b/drivers/net/phy/smsc.c index d8cac02a79b9..a521d48b22a7 100644 --- a/drivers/net/phy/smsc.c +++ b/drivers/net/phy/smsc.c @@ -44,6 +44,7 @@ static struct smsc_hw_stat smsc_hw_stats[] = { }; struct smsc_phy_priv { + u16 intmask; bool energy_enable; struct clk *refclk; }; @@ -58,7 +59,6 @@ static int smsc_phy_ack_interrupt(struct phy_device *phydev) static int smsc_phy_config_intr(struct phy_device *phydev) { struct smsc_phy_priv *priv = phydev->priv; - u16 intmask = 0; int rc; if (phydev->interrupts == PHY_INTERRUPT_ENABLED) { @@ -66,12 +66,15 @@ static int smsc_phy_config_intr(struct phy_device *phydev) if (rc) return rc; - intmask = MII_LAN83C185_ISF_INT4 | MII_LAN83C185_ISF_INT6; + priv->intmask = MII_LAN83C185_ISF_INT4 | MII_LAN83C185_ISF_INT6; if (priv->energy_enable) - intmask |= MII_LAN83C185_ISF_INT7; - rc = phy_write(phydev, MII_LAN83C185_IM, intmask); + priv->intmask |= MII_LAN83C185_ISF_INT7; + + rc = phy_write(phydev, MII_LAN83C185_IM, priv->intmask); } else { - rc = phy_write(phydev, MII_LAN83C185_IM, intmask); + priv->intmask = 0; + + rc = phy_write(phydev, MII_LAN83C185_IM, 0); if (rc) return rc; @@ -83,13 +86,8 @@ static int smsc_phy_config_intr(struct phy_device *phydev) static irqreturn_t smsc_phy_handle_interrupt(struct phy_device *phydev) { - int irq_status, irq_enabled; - - irq_enabled = phy_read(phydev, MII_LAN83C185_IM); - if (irq_enabled < 0) { - phy_error(phydev); - return IRQ_NONE; - } + struct smsc_phy_priv *priv = phydev->priv; + int irq_status; irq_status = phy_read(phydev, MII_LAN83C185_ISF); if (irq_status < 0) { @@ -97,7 +95,7 @@ static irqreturn_t smsc_phy_handle_interrupt(struct phy_device *phydev) return IRQ_NONE; } - if (!(irq_status & irq_enabled)) + if (!(irq_status & priv->intmask)) return IRQ_NONE; phy_trigger_machine(phydev); From patchwork Tue May 3 13:15:07 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 12835806 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2328C433EF for ; Tue, 3 May 2022 13:28:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236166AbiECNcI (ORCPT ); Tue, 3 May 2022 09:32:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51088 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236182AbiECNcD (ORCPT ); Tue, 3 May 2022 09:32:03 -0400 Received: from mailout2.hostsharing.net (mailout2.hostsharing.net [IPv6:2a01:37:3000::53df:4ee9:0]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98FD41D0D9; Tue, 3 May 2022 06:28:29 -0700 (PDT) Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (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-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "*.hostsharing.net", Issuer "RapidSSL TLS DV RSA Mixed SHA256 2020 CA-1" (verified OK)) by mailout2.hostsharing.net (Postfix) with ESMTPS id E34BD10189E0A; Tue, 3 May 2022 15:28:27 +0200 (CEST) Received: from localhost (unknown [89.246.108.87]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id C374A630FA12; Tue, 3 May 2022 15:28:27 +0200 (CEST) X-Mailbox-Line: From 95ff93fffa161a7a96604b4dfe2be933fe740785 Mon Sep 17 00:00:00 2001 Message-Id: <95ff93fffa161a7a96604b4dfe2be933fe740785.1651574194.git.lukas@wunner.de> In-Reply-To: References: From: Lukas Wunner Date: Tue, 3 May 2022 15:15:07 +0200 Subject: [PATCH net-next v2 7/7] net: phy: smsc: Cope with hot-removal in interrupt handler To: "David S. Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-usb@vger.kernel.org, Steve Glendinning , UNGLinuxDriver@microchip.com, Oliver Neukum , Andre Edich , Oleksij Rempel , Martyn Welch , Gabriel Hojda , Christoph Fritz , Lino Sanfilippo , Philipp Rosenberger , Heiner Kallweit , Andrew Lunn , Russell King , Ferry Toth Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org If reading the Interrupt Source Flag register fails with -ENODEV, then the PHY has been hot-removed and the correct response is to bail out instead of throwing a WARN splat and attempting to suspend the PHY. The PHY should be stopped in due course anyway as the kernel asynchronously tears down the device. Tested-by: Oleksij Rempel # LAN9514/9512/9500 Tested-by: Ferry Toth # LAN9514 Signed-off-by: Lukas Wunner Reviewed-by: Andrew Lunn --- drivers/net/phy/smsc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/phy/smsc.c b/drivers/net/phy/smsc.c index a521d48b22a7..35bff7fd234c 100644 --- a/drivers/net/phy/smsc.c +++ b/drivers/net/phy/smsc.c @@ -91,7 +91,9 @@ static irqreturn_t smsc_phy_handle_interrupt(struct phy_device *phydev) irq_status = phy_read(phydev, MII_LAN83C185_ISF); if (irq_status < 0) { - phy_error(phydev); + if (irq_status != -ENODEV) + phy_error(phydev); + return IRQ_NONE; }