From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751993AbeEGGzN (ORCPT ); Mon, 7 May 2018 02:55:13 -0400 Received: from lelnx194.ext.ti.com ([198.47.27.80]:32426 "EHLO lelnx194.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751082AbeEGGzK (ORCPT ); Mon, 7 May 2018 02:55:10 -0400 From: "Reizer, Eyal" To: Tony Lindgren CC: Eyal Reizer , "bcousson@baylibre.com" , "robh+dt@kernel.org" , "mark.rutland@arm.com" , "linux-omap@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "Loewy, Chen" Subject: RE: [EXTERNAL] Re: [PATCH] arm: dts: am437x-sk-evm: add wilink8 support Thread-Topic: [EXTERNAL] Re: [PATCH] arm: dts: am437x-sk-evm: add wilink8 support Thread-Index: AQHT4umNrIAS1VNvUkK07yas+IZ4paQiVQFAgADvToCAAJCfoA== Date: Mon, 7 May 2018 06:55:03 +0000 Message-ID: References: <1525159453-32489-1-git-send-email-eyalr@ti.com> <20180502145100.GK98604@atomide.com> <5cc906da15da45ab96e06957f878b65b@ti.com> <20180503141759.GP98604@atomide.com> <20180506165621.GL98604@atomide.com> In-Reply-To: <20180506165621.GL98604@atomide.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [137.167.25.139] x-exclaimer-md-config: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id w476tIcL001466 Hi Tony, > > Yeah my guess is that the reason for the separate GPIO interrupt was > that on omap3 we did not have SDIO interrupt working for years. This was > because of the issues related to padconf interrupts for off mode. > > We now have Linux generic wakeirq support working with SDIO and it has > been confirmed to work also for off mode with mwifiex at least. So > there should be no reason to not also use the SDIO interrupt. > There is more to this than just the padconf. Using in-band interrupt instead of the out of band one requires Supporting a feature called "Asynchronous interrupts in 4Bit mode" Which is part of SDIO 3.0 spec: https://www.sdcard.org/downloads/pls/pdf/index.php?p=PartE1_SDIO_Simplified_Specification_Ver3.00.jpg&f=PartE1_SDIO_Simplified_Specification_Ver3.00.pdf&e=EN_SSE1 Take a look at page 41 at the bottom part of the table. Wilink8 supports this feature but AFAIK this support is still not part of the mmc/sdio core in the Linux kernel. If we want wilink8 to trigger a host wakeup using the in-band interrupt instead Of the wlan_irq pin we would need to enable/use this feature. I did use it internally in the past and was able to patch the Ubuntu kernel (3.5.0 at that time) to use wilink8 in a standard SD Card slot of an Ubuntu Laptop while removing the use of wlan_irq pin completely. However this was an experimental patch set written by a third party that was not up-steamtable at that time. I do have this patch set somewhere... It is similar to the following patch which is not upstream as well for some reason: https://gitlab.com/k2wl/g2_kernel/commit/5c4970fdaa50422d7ea7220efa20fb35148a4bca It is not the only patch needed, there are a couple of additional patches needed for fully using it from driver. I did check latest Linux-next and don't see this support there. Not sure why. Best Regards, Eyal