External 32.768 kHz output
You can configure pad MCA_IO6 to output a 32.768 kHz signal for clocking external peripherals.
Kernel configuration
The 32.768 kHz output functionality is part of the MCA core driver and does not require any special kernel option.
Platform driver mapping
The MCA core driver is located at:
| File | Description |
|---|---|
| drivers/mfd/mca-cc6ul-core.c | ConnectCore 6UL MCA core driver |
Device tree bindings and customization
The 32.768 kHz functionality does not require any device tree property.
Using the 32.768 kHz output
The functionality is controlled by a sysfs entry. To enable the 32.768 kHz signal on MCA_IO6 pad:
~# echo enabled > /sys/bus/i2c/drivers/mca_cc6ul/0-007e/ext32_khz
To disable it:
~# echo disabled > /sys/bus/i2c/drivers/mca_cc6ul/0-007e/ext32_khz
To read the current status of the pad:
~# cat /sys/bus/i2c/drivers/mca_cc6ul/0-007e/ext32_khz disabled
