(Adding linux CCs) On 02/01/2010, at 7:19 PM, Hein_Tibosch wrote: > Almost good: on my Kingston Elite Pro (50x) SD-card, initialization will > only succeed if F <= 282258 Hz. ... > > I checked some datasheets of several makes: > > Delkin microSD min 0 max 400 > Swissbit min 0 max 400 > Sandisk 100 - 400 > Toshiba 100 - 400 > ST electronics 0 400 > SD-specification: Issue continues clock in frequency range of 100KHz-400KHz > If the Average frequency of the SDCLK is less than 100KHz then the card > may not be able to respond within the 1-second limit > > So what about 100 or 150 Khz? Ah geez, yeah this something else I was hoping to avoid with the V1 patch - an endless stream of "oh shit, this card's even /moore/ broken! Patch it, patch it good" Pierre, thoughts? All my cards were borderline spec but Hein's got a mainstream, common card which seems to completely ignore the spec. Can we just take the few-hundred-uS hit and allow initialization down at the bottom end, say 100kHz? <overkill> Or a KConfig option? </overkill> --Ben. -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
