bus: mhi: Move host MHI code to "host" directory

In preparation of the endpoint MHI support, let's move the host MHI code
to its own "host" directory and adjust the toplevel MHI Kconfig & Makefile.

While at it, let's also move the "pci_generic" driver to "host" directory
as it is a host MHI controller driver.

Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-5-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/bus/Makefile

@@ -39,4 +39,4 @@ obj-$(CONFIG_VEXPRESS_CONFIG)	+= vexpress-config.o
 obj-$(CONFIG_DA8XX_MSTPRI)	+= da8xx-mstpri.o
 
 # MHI
-obj-$(CONFIG_MHI_BUS)		+= mhi/
+obj-y				+= mhi/

drivers/bus/mhi/Kconfig

@@ -2,30 +2,7 @@
 #
 # MHI bus
 #
-# Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
+# Copyright (c) 2021, Linaro Ltd.
 #
 
-config MHI_BUS
-	tristate "Modem Host Interface (MHI) bus"
-	help
-	  Bus driver for MHI protocol. Modem Host Interface (MHI) is a
-	  communication protocol used by the host processors to control
-	  and communicate with modem devices over a high speed peripheral
-	  bus or shared memory.
-
-config MHI_BUS_DEBUG
-	bool "Debugfs support for the MHI bus"
-	depends on MHI_BUS && DEBUG_FS
-	help
-	  Enable debugfs support for use with the MHI transport. Allows
-	  reading and/or modifying some values within the MHI controller
-	  for debug and test purposes.
-
-config MHI_BUS_PCI_GENERIC
-	tristate "MHI PCI controller driver"
-	depends on MHI_BUS
-	depends on PCI
-	help
-	  This driver provides MHI PCI controller driver for devices such as
-	  Qualcomm SDX55 based PCIe modems.
-
+source "drivers/bus/mhi/host/Kconfig"

drivers/bus/mhi/Makefile

@@ -1,6 +1,2 @@
-# core layer
-obj-y += core/
-
-obj-$(CONFIG_MHI_BUS_PCI_GENERIC) += mhi_pci_generic.o
-mhi_pci_generic-y += pci_generic.o
-
+# Host MHI stack
+obj-y += host/

drivers/bus/mhi/host/Kconfig

@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# MHI bus
+#
+# Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
+#
+
+config MHI_BUS
+	tristate "Modem Host Interface (MHI) bus"
+	help
+	  Bus driver for MHI protocol. Modem Host Interface (MHI) is a
+	  communication protocol used by the host processors to control
+	  and communicate with modem devices over a high speed peripheral
+	  bus or shared memory.
+
+config MHI_BUS_DEBUG
+	bool "Debugfs support for the MHI bus"
+	depends on MHI_BUS && DEBUG_FS
+	help
+	  Enable debugfs support for use with the MHI transport. Allows
+	  reading and/or modifying some values within the MHI controller
+	  for debug and test purposes.
+
+config MHI_BUS_PCI_GENERIC
+	tristate "MHI PCI controller driver"
+	depends on MHI_BUS
+	depends on PCI
+	help
+	  This driver provides MHI PCI controller driver for devices such as
+	  Qualcomm SDX55 based PCIe modems.
+

drivers/bus/mhi/host/Makefile

@@ -1,4 +1,6 @@
 obj-$(CONFIG_MHI_BUS) += mhi.o
-
 mhi-y := init.o main.o pm.o boot.o
 mhi-$(CONFIG_MHI_BUS_DEBUG) += debugfs.o
+
+obj-$(CONFIG_MHI_BUS_PCI_GENERIC) += mhi_pci_generic.o
+mhi_pci_generic-y += pci_generic.o