MSM MHI DEV

MSM MHI DEV enables communication with the host over a PCIe link using the
Modem Host Interface protocol. The driver interfaces with the IPA for
enabling the HW acceleration channel path and provides interface for
software channels to communicate between Host and device.

Required properties:
  - compatible: should be "qcom,msm-mhi-dev" for MHI device driver.
  - reg: MHI MMIO physical register space.
  - reg-names: resource names used for the MHI MMIO physical address region,
	       IPA uC command and event ring doorbell mail box address.
	       Should be "mhi_mmio_base" for MHI MMIO physical address,
	       "ipa_uc_mbox_crdb" for IPA uC Command Ring doorbell,
	       "ipa_uc_mbox_erdb" for IPA uC Event Ring doorbell passed to
	       the IPA driver.
  - interrupts: The MHI interrupt used when Host issues request to
		process pending data to be read by the device.
  - interrupt-names: Should be mhi-device-inta for MHI interrupt.
  - qcom,mhi-ifc-id: ID of HW interface via which MHI on device side
		communicates with host side.
  - qcom,mhi-local-pa-base: MHI device local physical start address.
  - qcom,mhi-ep-msi: End point MSI number.
  - qcom,mhi-version: MHI specification version supported by the device.

Example:

	mhi: qcom,msm-mhi-dev {
		compatible = "qcom,msm-mhi-dev";
		reg = <0xfc527000 0x1000>,
		     <0xfd4fa000 0x1>,
		     <0xfd4fa080 0x1>;
		reg-names = "mhi_mmio_base", "ipa_uc_mbox_crdb",
			    "ipa_uc_mbox_erdb";
		interrupts = <0 42 0>;
		interrupt-names = "mhi-device-inta";
		qcom,mhi-ifc-id = <0x030017cb>;
		qcom,mhi-local-pa-base = <80000000>;
		qcom,mhi-ep-msi = <1>;
		qcom,mhi-version = <0x1000000>;
	};
