Hello Everyone,
Recently I looked into the onboard LED labels and triggers for 96Boards in Linux kernel. It looked very obvious that there is no standard or recommended way of implementation and every board implements its own way.
This will become cumbersome to maintain userspace support in MRAA library, which we recommend for peripherals access. So I thought of standardizing it across all mainline supported 96Boards.
Below is the format I came up with:
device-name:green:user1 default-trigger: heartbeat device-name:green:user2 default-trigger: onboard-storage (mmc0 or disk-activity) device-name:green:user3 default-trigger: SD-card (mmc1) device-name:green:user4 default-trigger: none, panic-indicator device-name:yellow:wlan default-trigger: phy0tx device-name:blue:bt default-trigger: hci0-power
Issues:
1. We have MMC and SATA triggers but no UFS trigger AFAIK. So, boards implementing UFS storage will not use LED 2.
2. Currently, we can't specify the order of storage devices. It is preferred to assign "storage0" for onboard memory but it will not be true all the time.
3. Not sure whether "phy0tx" will work with boards with Ethernet interfaces.
4. Modifying the LED labels may break current userspace scripts implemented by the users. But it will favor MRAA library for providing a generic interface to LEDs.
I hope to get feeback on the above proposal here so that we can move forward with it. If we can agree on a common format, we can also discuss to add it as a recommendation in the Specs.
Thanks, Mani