From: Zhao Yakui <yakui.zhao@xxxxxxxxx> Hi, ACPI 4.0 spec adds the ACPI IPMI opregion, which means that the ACPI AML code can also communicate with the BMC controller. This patch set is to install the ACPI IPMI opregion space handler and enable the ACPI to access the BMC controller through the IPMI message. [Patch 01/02]: Export symbol of pnp_bus_type [Patch 02/02]: Install the IPMI space handler to enable ACPI to access the BMC controller V6->V7: Based on Corey Minyard's comments, the IPMI opregion handler is put into the separate file again as it only uses the API interface provided by IPMI system. Now it is put into the ACPI subsystem. V5->V6: Adjust the patch order and refresh the patch set. V4->V5: According to Bjorn's comment, remove the unnecessary comment. The debug info will be printed by using dev_err/dev_warn instead of by using printk directly. V3->V4: According to Bjorn's comment, delete the meaningless variable initialization and check. We also do some cleanup. V2->V3: According to Bjorn's comment, this IPMI opregion code is put into the IPMI subsystem(ipmi_si_intf.c). In such case the part of IPMI opregion code will be installed automatically when IPMI detection module is loaded. When the IPMI system interface is detected by loading PNP device driver, we will record every IPMI system interface defined in ACPI namespace and then install the corresponding IPMI opregion space handler, which is used to enable ACPI AML code to access the BMC controller. V1->V2: According to Bjorn's comment, we won't install the IPMI space handler by loading an ACPI device driver. Instead we will enumerate the ACPI IPMI device directly in ACPI device tree and then install the IPMI space handler. Then ACPI AML code and access the BMC controller through the IPMI space handler. Best regards. Yakui -- 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