From mboxrd@z Thu Jan 1 00:00:00 1970 From: k.kozlowski@samsung.com (Krzysztof Kozlowski) Date: Wed, 14 Oct 2015 10:15:50 +0900 Subject: [PATCH 3/3] ARM: dts: exynos5422-odroidxu3: Added UHS-I bus speed support In-Reply-To: References: <1444578364-1384-1-git-send-email-linux.amoon@gmail.com> <1444578364-1384-3-git-send-email-linux.amoon@gmail.com> <561B48B7.1040201@samsung.com> <561C4CEE.3050905@samsung.com> <561C7DF1.6000609@samsung.com> <561D9ACE.6050103@samsung.com> Message-ID: <561DACC6.9040209@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 14.10.2015 10:06, Alim Akhtar wrote: > +Doug > Hello, > AFAIR, dw_mmc host controller does support UHS-I [1], specially SDR50 > and SDR104 modes. > > [1]: http://www.spinics.net/lists/linux-mmc/msg28186.html > > What I remember is, one need to set "broken-cd" property also in order > to make it work because of the vqmmc and vmmc connection on board. I > didn't find the link right now, but you can search on the web, there > was a long discussion about handling this. > Have not checked it recently, so not sure if this got broken somehow. > Please, don't top post. I am not a SD/MMC specialist (I do not feel enough confident in its internals) but the datasheet for 5422 does not mention UHS. However it mentions "High Speed DDR Mode with 200 MHz clock rate (HS400)". This does not look like UHS... https://www.sdcard.org/developers/overview/bus_speed/ This of course is not a definite proof that 5422 does not support UHS. I am just saying that I couldn't find any information that *it does*. Best regards, Krzysztof