support DigitialInOutProtocol for CS of sdcardio.SDCard

[bablokb]

This fixes #11047. The implementation is basically a copy&paste&edit of what fourwire.FourWire does.

Tested on an upcoming Waveshare board that uses SD_CS behind an ioexpander, and on a Pico with a normal SD breakout attached.

[bablokb]

With my last fix, all builds are now successful.

@dhalbert , @mikeysklar : I don't have the hardware to test the automount feature (I never bothered to route the sd-card-detect pin on my pcbs). It would be great if one of you could do a test on one of the boards with integrated sd-card that use this feature (e.g. adalogger, fruit-jam).

[mikeysklar]

checking now on a Metro RP2350

[mikeysklar]

I tried this PR on a Metro RP2350 and connected it two different hosts macOS and Linux.

CircuitPython 10.3.0-alpha.2-31-g6285efc59e-dirty

I'm not seeing the microSD drive pass through correctly. Tried both exFAT (64GB) and FAT32 (16GB) cards.

On macOS I get this error.

"The disk you attached was not readable by this computer."

The disk device is visible, but the filesystem fails to mount.

It looks like this is passing an address instead of an object.

common_hal_digitalio_digitalinout_never_reset(MP_OBJ_TO_PTR(&sdcard.cs));

should be:

common_hal_digitalio_digitalinout_never_reset(MP_OBJ_TO_PTR(sdcard.cs));

Will confirm.

[mikeysklar]

Yep, that fixed it:

Ubuntu 24.04.4 LTS:

/dev/sdb1          15328     1724     13604  12% /media/sklarm/CIRCUITPY
/dev/sdc1       61794304    14336  61779968   1% /media/sklarm/64GB_SD

macOS Tahoe 26.5.1:

/dev/disk4s1        30660      3452     27208    12%       0          0     -   /Volumes/CIRCUITPY
/dev/disk5s1    123588864     28928 123559936     1%       1          0  100%   /Volumes/64GB_SD