On 28/03/2024 13:13, Patryk wrote: > Hi, > I've got a question regarding sd cards, their specifications, and the > ability to support them by a host controller. > In my eSDHC (NXP LS1028a soc) features summary I can find the following: > - Conforms to the SD Host controller standard specification version > 3.0, including test event register support > - Compatible with the SD memory card specification version 3.01, and > supports the high-capacity SD memory card > - Compatible with the SDIO card specification version 3.0 > > I have found that SD cards compatible with SD card specification 4.10 > and higher support something like an extension register and in > particular power management. I've searched through kernel code and > found that these registers are parsed by the let's say generic part of > sd/mmc subsystem not by the host controller driver. > Does it mean that I can connect the SD card compatible with spec 4.10 > and expect that the sd/mmc subsystem will use power management > features if the card supports them? Yes. mmc core will handle it if the card supports it. "power management features" is a bit misleading, it's SD_EXT_POWER_OFF_NOTIFY. > Best regards > Patryk >
