From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: SDIO "SD2" vs. SD-card "SD3" interface on BayTrail Date: Tue, 04 Jul 2017 18:56:31 +0300 Message-ID: <1499183791.22624.257.camel@linux.intel.com> References: <1499176431.22624.255.camel@linux.intel.com> <05ba15dc-b7b0-0760-ee0b-67fec71e9736@denx.de> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Return-path: Received: from mga06.intel.com ([134.134.136.31]:47307 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752484AbdGDP6F (ORCPT ); Tue, 4 Jul 2017 11:58:05 -0400 In-Reply-To: <05ba15dc-b7b0-0760-ee0b-67fec71e9736@denx.de> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Stefan Roese , linux-mmc@vger.kernel.org Cc: Adrian Hunter On Tue, 2017-07-04 at 16:12 +0200, Stefan Roese wrote: > > On 04.07.2017 15:53, Andy Shevchenko wrote: > > On Tue, 2017-07-04 at 14:53 +0200, Stefan Roese wrote: > > > Hi, > > > > > > we are currently investigating, if its possible to connect a SDIO > > > device (WLAN module) to the SD-card interface "SD3" of the > > > BayTrail > > > SoC instead of the SDIO interface "SD2". The BayTrail manual > > > states, > > > that the SDIO interface is capable of connecting SDIO devices. Is > > > this also possible for the SD-card interface "SD3", even if its > > > not > > > explicitly mentioned in the manual? If not, why is this not > > > possible? > > > > > > Any insight on this would be really helpful. > > > > Hmm... I have no documentation for SD/SDIO/eMMC for BayTrail except > > the > > public one. Internally I found some charts that shows similarities > > between two. So, taking that into consideration I would suggest to > > try > > it out on real hardware (MinnowBoard MAX, for example), only > > impediment > > I can see is the absence of support in the drivers in Linux OS. If > > you > > need it only in U-Boot, you perhaps may fix it easily. > > Its not only for U-Boot unfortunately. Do you think, a quick test in  > Linux should be possible by simply swapping the PCI device IDs in > sdhci-pci.core.c (PCI_DEVICE_ID_INTEL_BYT_SDIO vs. > PCI_DEVICE_ID_INTEL_BYT_SD)? If it utilizes ACPI (card detection) I'm not sure you can magically get it working, though it worth to try. -- Andy Shevchenko Intel Finland Oy