HID: intel-ish-hid: ISH firmware loader client driver

This driver adds support for loading Intel Integrated Sensor Hub (ISH) firmware
from host file system to ISH SRAM and start execution.

At power-on, the ISH subsystem shall boot to an interim Shim loader-firmware,
which shall expose an ISHTP loader device.

The driver implements an ISHTP client that communicates with the Shim ISHTP
loader device over the intel-ish-hid stack, to download the main ISH firmware.

Signed-off-by: Rushikesh S Kadam <rushikesh.s.kadam@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Nick Crews <ncrews@chromium.org>
Tested-by: Jett Rink <jettrink@chromium.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/Makefile

@@ -134,3 +134,4 @@ obj-$(CONFIG_USB_KBD)		+= usbhid/
 obj-$(CONFIG_I2C_HID)		+= i2c-hid/
 
 obj-$(CONFIG_INTEL_ISH_HID)	+= intel-ish-hid/
+obj-$(INTEL_ISH_FIRMWARE_DOWNLOADER)	+= intel-ish-hid/

drivers/hid/intel-ish-hid/Kconfig

@@ -14,4 +14,19 @@ config INTEL_ISH_HID
 	  Broxton and Kaby Lake.
 
 	  Say Y here if you want to support Intel ISH. If unsure, say N.
+
+config INTEL_ISH_FIRMWARE_DOWNLOADER
+	tristate "Host Firmware Load feature for Intel ISH"
+	depends on INTEL_ISH_HID
+	depends on X86
+	help
+	  The Integrated Sensor Hub (ISH) enables the kernel to offload
+	  sensor polling and algorithm processing to a dedicated low power
+	  processor in the chipset.
+
+	  The Host Firmware Load feature adds support to load the ISH
+	  firmware from host file system at boot.
+
+	  Say M here if you want to support Host Firmware Loading feature
+	  for Intel ISH. If unsure, say N.
 endmenu

drivers/hid/intel-ish-hid/Makefile

@@ -20,4 +20,7 @@ obj-$(CONFIG_INTEL_ISH_HID) += intel-ishtp-hid.o
 intel-ishtp-hid-objs := ishtp-hid.o
 intel-ishtp-hid-objs += ishtp-hid-client.o
 
+obj-$(CONFIG_INTEL_ISH_FIRMWARE_DOWNLOADER) += intel-ishtp-loader.o
+intel-ishtp-loader-objs += ishtp-fw-loader.o
+
 ccflags-y += -Idrivers/hid/intel-ish-hid/ishtp