Module ext_csd 

EXT_CSD byte offsets the driver currently consumes. Full register is 512 bytes; only document the ones we read.

Modules

device_type

Constants

BUS_WIDTH

Selected bus width (0 = 1-bit, 1 = 4-bit, 2 = 8-bit; 5 = 4-bit DDR, 6 = 8-bit DDR).

DEVICE_TYPE

Card type (HS / HS200 / HS400 support bitmap).

HS_TIMING

Selected timing mode after CMD6 (0 = backwards compat, 1 = HS, 2 = HS200, 3 = HS400). Same byte is also written to switch modes.

SEC_COUNT

Sector count (LE u32) — authoritative capacity for ≥2 GB cards.