ACMD41 argument is different between SD mode and SPI mode.
In SPI mode, the only non-zero bit may be the HCS bit. Unlike the SD
mode, the bits reflecting the host's OCR should be zero.
Previously, we used to set these bits the same way as for the SD mode.
This has caused certain cards to fail initializing, apparently their
controllers have checked the ACMD41 argument more strictly and refused
to finish initialization, resulting in an error such as
sdmmc_common: sdmmc_init_ocr: send_op_cond (1) returned 0x107
(Note that this error may have other causes than the one fixed in
this commit. For example, if the card doesn't have a sufficient and
stable power supply, it may also fail to complete the internal
initialization process, and will never clear the busy flag in R1
response.)
Closes https://github.com/espressif/esp-idf/issues/6686
Closes https://github.com/espressif/esp-idf/issues/10542
Works for 3.3V eMMC in 4 line mode.
Not implemented:
- DDR mode for SD cards (UHS-I) also need voltage to be switched to 1.8V.
- 8-line DDR mode for eMMC to be implemented later.