s390/cio: add eadm subchannel driver

This driver allows usage of EADM subchannels. EADM subchannels
act as a communication vehicle for SCM increments.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 3781db2..3f42161 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -440,6 +440,17 @@
 	help
 	  Bus driver for Storage Class Memory.
 
+config EADM_SCH
+	def_tristate m
+	prompt "Support for EADM subchannels"
+	depends on SCM_BUS
+	help
+	  This driver allows usage of EADM subchannels. EADM subchannels act
+	  as a communication vehicle for SCM increments.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called eadm_sch.
+
 endmenu
 
 menu "Dump support"
diff --git a/arch/s390/include/asm/isc.h b/arch/s390/include/asm/isc.h
index 1420a11..5ae6064 100644
--- a/arch/s390/include/asm/isc.h
+++ b/arch/s390/include/asm/isc.h
@@ -14,6 +14,7 @@
 /* Regular I/O interrupts. */
 #define IO_SCH_ISC 3			/* regular I/O subchannels */
 #define CONSOLE_ISC 1			/* console I/O subchannel */
+#define EADM_SCH_ISC 4			/* EADM subchannels */
 #define CHSC_SCH_ISC 7			/* CHSC subchannels */
 /* Adapter interrupts. */
 #define QDIO_AIRQ_ISC IO_SCH_ISC	/* I/O subchannel in qdio mode */