staging: greybus: move the greybus core to drivers/greybus

The Greybus core code has been stable for a long time, and has been
shipping for many years in millions of phones. With the advent of a
recent Google Summer of Code project, and a number of new devices in the
works from various companies, it is time to get the core greybus code
out of staging as it really is going to be with us for a while.

Cc: Johan Hovold <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Acked-by: Viresh Kumar <[e-mail]>
Acked-by: Alex Elder <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

MAINTAINERS

···
 M:	Greg Kroah-Hartman <[e-mail]>
 S:	Maintained
 F:	drivers/staging/greybus/
+F:	drivers/greybus/
+F:	include/linux/greybus.h
+F:	include/linux/greybus/
 L:	[e-mail] (moderated for non-subscribers)
 
 GREYBUS UART PROTOCOLS DRIVERS

drivers/Kconfig

···
 
 source "drivers/xen/Kconfig"
 
+source "drivers/greybus/Kconfig"
+
 source "drivers/staging/Kconfig"
 
 source "drivers/platform/Kconfig"

drivers/Makefile

···
 obj-$(CONFIG_VHOST_RING)	+= vhost/
 obj-$(CONFIG_VHOST)		+= vhost/
 obj-$(CONFIG_VLYNQ)		+= vlynq/
+obj-$(CONFIG_GREYBUS)		+= greybus/
 obj-$(CONFIG_STAGING)		+= staging/
 obj-y				+= platform/
 

drivers/greybus/Kconfig

···
+# SPDX-License-Identifier: GPL-2.0
+menuconfig GREYBUS
+	tristate "Greybus support"
+	depends on SYSFS
+	---help---
+	  This option enables the Greybus driver core.  Greybus is an
+	  hardware protocol that was designed to provide Unipro with a
+	  sane application layer.  It was originally designed for the
+	  ARA project, a module phone system, but has shown up in other
+	  phones, and can be tunneled over other busses in order to
+	  control hardware devices.
+
+	  Say Y here to enable support for these types of drivers.
+
+	  To compile this code as a module, chose M here: the module
+	  will be called greybus.ko

drivers/greybus/Makefile

···
+# SPDX-License-Identifier: GPL-2.0
+# Greybus core
+greybus-y :=	core.o		\
+		debugfs.o	\
+		hd.o		\
+		manifest.o	\
+		module.o	\
+		interface.o	\
+		bundle.o	\
+		connection.o	\
+		control.o	\
+		svc.o		\
+		svc_watchdog.o	\
+		operation.o
+
+obj-$(CONFIG_GREYBUS)		+= greybus.o
+
+# needed for trace events
+ccflags-y += -I$(src)

drivers/staging/greybus/Kconfig

···
 # SPDX-License-Identifier: GPL-2.0
-menuconfig GREYBUS
-	tristate "Greybus support"
-	depends on SYSFS
-	---help---
-	  This option enables the Greybus driver core.  Greybus is an
-	  hardware protocol that was designed to provide Unipro with a
-	  sane application layer.  It was originally designed for the
-	  ARA project, a module phone system, but has shown up in other
-	  phones, and can be tunneled over other busses in order to
-	  control hardware devices.
-
-	  Say Y here to enable support for these types of drivers.
-
-	  To compile this code as a module, chose M here: the module
-	  will be called greybus.ko
-
 if GREYBUS
 
 config GREYBUS_ES2

drivers/staging/greybus/Makefile

···
 # SPDX-License-Identifier: GPL-2.0
-# Greybus core
-greybus-y :=	core.o		\
-		debugfs.o	\
-		hd.o		\
-		manifest.o	\
-		module.o	\
-		interface.o	\
-		bundle.o	\
-		connection.o	\
-		control.o	\
-		svc.o		\
-		svc_watchdog.o	\
-		operation.o
-
-obj-$(CONFIG_GREYBUS)		+= greybus.o
-
 # needed for trace events
 ccflags-y += -I$(src)
-
 
 # Greybus Host controller drivers
 gb-es2-y := es2.o

drivers/staging/greybus/es2.c

···
 #include <asm/unaligned.h>
 
 #include "arpc.h"
-#include "greybus_trace.h"
+#include "../../greybus/greybus_trace.h"
 
 
 /* Default timeout for USB vendor requests. */