Power Sequencing for Enumerable Busses - What's Still Missing From the Device Tree and Kernel

Explore power sequencing challenges for enumerable buses in Device Tree platforms through this 19-minute conference talk from the Linux Plumbers Conference. Examine the differences between x86/ACPI platforms where devices are directly visible to the OS and Device Tree platforms that require additional power sequencing steps like regulator supply toggling and GPIO line management. Learn about existing solutions that currently work, identify gaps in Device Tree specifications, and discover kernel implementation issues where Device Tree definitions exist but lack proper kernel support. Analyze accumulated workarounds and technical debt that need cleanup in the Linux kernel's power management subsystem for enumerable bus devices.