On 8 January 2013 20:36, Nicolas Pitre <nicolas.pitre@xxxxxxxxxx> wrote: > On Tue, 8 Jan 2013, Johan Rudholm wrote: > >> This patch series attempts to make the 1.8V signal voltage switch >> required for UHS mode work according to the SD specification. >> >> These patches have been tested with a couple of UHS SD cards, one of >> which sometimes requires up to five power cycles before it accepts the >> signal voltage switch. > > Any idea why this is the case? > No, not really. But to comply with the sd spec this updated voltage sequence is needed. I think we need to understand the internal electrical voltage switch behaviour of that particular sd card to answer this. I doubt we can get hold of that information in the spec of the card, unfortunately. > > Nicolas Kind regards Ulf Hansson -- 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
