From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kalle Valo Subject: Re: [PATCH V2] wlcore: sdio: Fixup power on/off sequence Date: Wed, 16 Jan 2019 18:18:00 +0200 Message-ID: <87muo04lvr.fsf@codeaurora.org> References: <20190116113723.15668-1-ulf.hansson@linaro.org> <20190116154311.GP5544@atomide.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: (Ulf Hansson's message of "Wed, 16 Jan 2019 16:48:40 +0100") Sender: linux-kernel-owner@vger.kernel.org To: Ulf Hansson Cc: Tony Lindgren , Eyal Reizer , linux-wireless@vger.kernel.org, Ricardo Salveti , Kishon Vijay Abraham I , Anders Roxell , John Stultz , Jan Kiszka , Linux Kernel Mailing List , linux-omap List-Id: linux-omap@vger.kernel.org Ulf Hansson writes: > On Wed, 16 Jan 2019 at 16:43, Tony Lindgren wrote: >> >> * Ulf Hansson [190116 11:37]: >> > During "wlan-up", we are programming the FW into the WiFi-chip. However, >> > re-programming the FW doesn't work, unless a power cycle of the WiFi-chip >> > is made in-between the programmings. >> > >> > To conform to this requirement and to fix the regression in a simple way, >> > let's start by allowing that the SDIO card (WiFi-chip) may stay powered on >> > (runtime resumed) when wl12xx_sdio_power_off() returns. The intent with the >> > current code is to treat this scenario as an error, but unfortunate this >> > doesn't work as expected, so let's fix this. >> > >> > The other part is to guarantee that a power cycle of the SDIO card has been >> > completed when wl12xx_sdio_power_on() returns, as to allow the FW >> > programming to succeed. However, relying solely on runtime PM to deal with >> > this isn't sufficient. For example, userspace may prevent runtime suspend >> > via sysfs for the device that represents the SDIO card, leading to that the >> > mmc core also keeps it powered on. For this reason, let's instead do a >> > brute force power cycle in wl12xx_sdio_power_on(). >> > >> > Fixes: 728a9dc61f13 ("wlcore: sdio: Fix flakey SDIO runtime PM handling") >> > Signed-off-by: Ulf Hansson >> > --- >> > >> > Changes in v2: >> > - Keep the SDIO host claimed when calling mmc_hw_reset(). >> > - Add a fixes tag. >> >> This v2 version works for me as tested with: >> >> # while [ 1 ]; do ifconfig wlan0 down; ifconfig wlan0 up; done >> [ 181.364990] wlcore: down >> [ 182.116424] wlcore: firmware booted (Rev 6.3.10.0.141) >> [ 182.151641] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready >> [ 182.166778] wlcore: down >> [ 182.773132] wlcore: firmware booted (Rev 6.3.10.0.141) >> [ 182.811096] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready >> ... >> >> Thanks for fixing this issue properly, and feel free to add: >> >> Tested-by: Tony Lindgren > > Thanks for testing, great news! > > Before queuing this as fix, let's also see what the Hikey folkz thinks > of this. I have pinged Anders and he is currently running a test > suite. > > Kalle, can you please tag this for stable as well? Ok, I'll queue this for 5.0 (but wait for testing feedback at least a day) and add: Cc: -- Kalle Valo