From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] net: ethernet : stmicro: fixed power suspend and resume failure in stmmac driver Date: Tue, 30 Sep 2014 15:10:56 -0400 (EDT) Message-ID: <20140930.151056.950254777090461575.davem@davemloft.net> References: <1412056534-7995-1-git-send-email-hliang1025@gmail.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: peppe.cavallaro@st.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, adi-linux-docs@lists.sourceforge.net To: hliang1025@gmail.com Return-path: In-Reply-To: <1412056534-7995-1-git-send-email-hliang1025@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Date: Tue, 30 Sep 2014 13:55:34 +0800 > From: Hao Liang > > This is the fix for a power management issue caused by suspend and resume function in stmmac_main.c. > After enable CONFIG_DEBUG_ATOMIC_SLEEP which enable sleep-inside atomic section checking, power > managemet can not work normally. Board couldn't wakeup successfully after suspend. Command > "echo mem > /sys/power/state" suspend the board. > > In suspend and resume function of stmmac driver, there are some sleep-inside function in atomic section > created by spin lock. These functions will causes system warnings and wakeup issue when enable > CONFIG_DEBUG_ATOMIC_SLEEP. > > This bug was fixed by: > * replace some sleep function with non-sleep function > clk_disable_unprepare -> clk_disable ... > * decrease the atomic area created by spin lock function. The original atomic area in resume function is > too large. > > Signed-off-by: Hao Liang I really think the ->mac->xxx calls need to be under the lock, and therefore this spinlock region shortening is not valid.