From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1033389AbeE1KVp (ORCPT ); Mon, 28 May 2018 06:21:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:41028 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1033328AbeE1KVc (ORCPT ); Mon, 28 May 2018 06:21:32 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Esben Haabendal , Andrew Lunn , "David S. Miller" , Sasha Levin Subject: [PATCH 4.4 166/268] dp83640: Ensure against premature access to PHY registers after reset Date: Mon, 28 May 2018 12:02:20 +0200 Message-Id: <20180528100221.183310565@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180528100202.045206534@linuxfoundation.org> References: <20180528100202.045206534@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Esben Haabendal [ Upstream commit 76327a35caabd1a932e83d6a42b967aa08584e5d ] The datasheet specifies a 3uS pause after performing a software reset. The default implementation of genphy_soft_reset() does not provide this, so implement soft_reset with the needed pause. Signed-off-by: Esben Haabendal Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/phy/dp83640.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) --- a/drivers/net/phy/dp83640.c +++ b/drivers/net/phy/dp83640.c @@ -1203,6 +1203,23 @@ static void dp83640_remove(struct phy_de kfree(dp83640); } +static int dp83640_soft_reset(struct phy_device *phydev) +{ + int ret; + + ret = genphy_soft_reset(phydev); + if (ret < 0) + return ret; + + /* From DP83640 datasheet: "Software driver code must wait 3 us + * following a software reset before allowing further serial MII + * operations with the DP83640." + */ + udelay(10); /* Taking udelay inaccuracy into account */ + + return 0; +} + static int dp83640_config_init(struct phy_device *phydev) { struct dp83640_private *dp83640 = phydev->priv; @@ -1496,6 +1513,7 @@ static struct phy_driver dp83640_driver .flags = PHY_HAS_INTERRUPT, .probe = dp83640_probe, .remove = dp83640_remove, + .soft_reset = dp83640_soft_reset, .config_init = dp83640_config_init, .config_aneg = genphy_config_aneg, .read_status = genphy_read_status,