From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ludovic Desroches Subject: Re: [RFC PATCH] mmc: sdhci-of-at91: don't put device in suspend after probe Date: Wed, 10 Feb 2016 15:16:24 +0100 Message-ID: <20160210141624.GC14937@odux.rfo.atmel.com> References: <1455098283-14500-1-git-send-email-ludovic.desroches@atmel.com> <56BB2414.1040606@intel.com> <20160210125139.GB14937@odux.rfo.atmel.com> <56BB3459.6090506@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Return-path: Received: from eusmtp01.atmel.com ([212.144.249.243]:59764 "EHLO eusmtp01.atmel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751168AbcBJOQ2 (ORCPT ); Wed, 10 Feb 2016 09:16:28 -0500 Content-Disposition: inline In-Reply-To: <56BB3459.6090506@intel.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Adrian Hunter Cc: nicolas.ferre@atmel.com, Ludovic Desroches , ulf.hansson@linaro.org, linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org On Wed, Feb 10, 2016 at 03:00:09PM +0200, Adrian Hunter wrote: > On 10/02/16 14:51, Ludovic Desroches wrote: > > Hi Adrian, > > > > On Wed, Feb 10, 2016 at 01:50:44PM +0200, Adrian Hunter wrote: > >> On 10/02/16 11:58, Ludovic Desroches wrote: > >>> By putting the device in suspend at the end of the probe, it is > >>> impossible to wake up on non software event such as card > >>> insertion/removal. > >>> > >>> Signed-off-by: Ludovic Desroches > >>> --- > >>> > >>> Hi, > >>> > >>> Since I had no feedback on this topic: > >>> http://permalink.gmane.org/gmane.linux.kernel.mmc/35160 > >>> > >>> I would like to no more put the device in suspend at the end of the probe. If > >>> my device is suspended at the end of the probe, I have no issue to resume on > >>> a software event such as mounting my sdcard but hardware event such as card > >>> insertion and removal do not trigger a resume. > >> > >> You can't use runtime PM unless you have a way to wake-up. > >> > > > > Thanks for your feedback. I am a bit disappointed since Ulf advised me to use > > runtime PM instead of system PM. > > > >> Currently, sdhci disables card detect interrupts when runtime suspended, > >> and drivers use a card-detect GPIO to wake-up. > >> > > > > It is what I have seen going through the sdhci layer. So next question is: > > is it normal to not take care of card detect interrupts? We keep enabled > > some IRQs probably for SDIO modules IRQ but not for card detection. I > > don't understand the reason. > > Does sdhci-of-at91.c generate card detect interrupts while runtime suspended? It could if I keep one or two clocks enabled (need extra tests to be sure about the clock needed to get this interrupt). I have tried to modify quickly sdhci_runtime_suspend_host() to enable card insertion/removal, there is an irq generated but the kernel complains this irq is not handled. I didn't dig further, it was only to do a simple test. > > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html