From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [PATCH] wlcore: Fix bringing up wlan0 again if powered down briefly Date: Tue, 18 Dec 2018 07:54:39 -0800 Message-ID: <20181218155439.GB6707@atomide.com> References: <20181217164207.20081-1-tony@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-wireless-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Ulf Hansson Cc: Kalle Valo , Eyal Reizer , Kishon Vijay Abraham I , Guy Mishol , linux-wireless-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-omap , Anders Roxell , John Stultz , Ricardo Salveti List-Id: linux-omap@vger.kernel.org Hi, * Ulf Hansson [181218 12:34]: > Instead, it looks like what you need, is a way to keep track of > whether the SDIO card, became power cycled or if it stayed powered on, > when "ifconfig wlan0 up" is done. In case of a power cycle, you need > to re-program the firmware, right? Yeah mostly. But we also need to ensure things do get powered down properly after ifconfig wlan0 down :) IMO after ifconfig wlan0 down returns, there should be no waiting needed. > Would it be possible to re-program the firmware, even if the SDIO card > stayed powered-on? That might help for some cases, but the problem of how to ensure the card is powered down after ifconfig wlan0 down returns still exists. > In regards to delays needed due to a capacitance. If that really is > the case, that shall be the managed by the mmc core, as it's there the > power cycle sequence is being done. As a matter of fact, you should be > able to use drivers/mmc/core/pwrseq_simple.c and extend > "power-off-delay-us" in the DTB for Hikey if that is needed. Hmm I do have a mostly done wlcore pwrseq driver here somewhere that I have not had a chance to finish again. But that's not going to work for a fix and needs updating of the related dts files too. Regards, Tony