- * This is an SMBus write. We will bypass the entire field mechanism
- * and handoff the buffer directly to the handler.
+ * This is an SMBus or IPMI write. We will bypass the entire field
+ * mechanism and handoff the buffer directly to the handler. For
+ * these address spaces, the buffer is bi-directional; on a write,
+ * return data is returned in the same buffer.
+ *
+ * Source must be a buffer of sufficient size:
+ * ACPI_SMBUS_BUFFER_SIZE or ACPI_IPMI_BUFFER_SIZE.