On Sun, Jun 14, 2026 at 02:04:37AM +0200, Mart?? Alonso wrote: >At idle state, prior initialization, MMC cards (not SD) will respond >with illegal command to anything other than CMD1 (MMC_SEND_OP_COND) and >CMD58 (MMC_READ_OCR). The MMC driver initially sends CMD8 >(SD_SEND_IF_COND) to check for an SD card, but this needs to return an >error, if not an SD card, so it can later check for an MMC card with >CMD1 (MMC_SEND_OP_COND).
CMD8 is supported in SD 2.0+, so this might break SD 1.0. > >Additionally, CMD55 + ACMD41 (SD_APP_SEND_OP_COND) can be skipped if >CMD8 (SD_SEND_IF_COND) already failed. > Regards Peng
