Messages in this thread | | | From | Philip Rakity <> | Date | Wed, 17 Oct 2012 21:56:32 +0200 | Subject | Re: [PATCH 1/2] mmc: core: Support all MMC capabilities when booting from Device Tree |
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On 17 Oct 2012, at 14:38, Arnd Bergmann <arnd@arndb.de> wrote:
> On Monday 15 October 2012, Lee Jones wrote: >>> and so on. What are you actually missing in the properties that >>> are already there? >> >> MMC_CAP_ERASE > > This one seems to be set unconditionally on some controllers but > not on others. Why would it need to be configurable? > >> MMC_CAP_UHS_SDR12 >> MMC_CAP_UHS_SDR25 >> MMC_CAP_UHS_DDR50 > > Could this be derived from max-frequency?
The problem is the controller may signal it supports DDR but the host cannot. For example no voltage at correct level. Same issue with 8 bit support. Controller could say supports it but board has only 4 "wires" > >> MMC_CAP_1_8V_DDR > > Right, I suppose we need this. Should we have a minimum and maximum > voltage added to the common properties for this? > >> MMC_CAP2_DETECT_ON_ERR >> MMC_CAP2_NO_SLEEP_CMD > > I don't see these ones being set anywhere, but they were both > added by Ulf. Maybe he can comment on if or why they are needed > in devicetree, rather than being set by the driver unconditionally > or for specific versions of the host controller. > > Arnd > -- > 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
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