Hi, Preempt isn't disabled between ec_burst_enable()/ec_burst_disable(), so it's very likely there is a preemption between them and make the timing for burst mode not comply with ACPI spec (400ms for first access and 50ms for subsequent access). We have a system with broken EC and the BIOS engineer identified it's the timing issue. What's the judgment why Linux doesn't comply with ACPI spec? Thanks, Shaohua -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html