s390/zcrypt: New config switch CONFIG_ZCRYPT_DEBUG

Introduce a new config switch CONFIG_ZCRYPT_DEBUG which
will be used to enable some features for debugging the
zcrypt device driver and ap bus system:

Another patch will use this for displaying ap card and
ap queue state information via sysfs attribute.

A furher patch will use this to enable some special
treatment for some fields of an crypto request to be able
to inject failures and so help debugging with regards
to handling of failures.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

drivers/crypto/Kconfig

@@ -71,10 +71,26 @@ config ZCRYPT
 	help
 	  Select this option if you want to enable support for
 	  s390 cryptographic adapters like:
-	  + PCI-X Cryptographic Coprocessor (PCIXCC)
-	  + Crypto Express 2,3,4 or 5 Coprocessor (CEXxC)
-	  + Crypto Express 2,3,4 or 5 Accelerator (CEXxA)
-	  + Crypto Express 4 or 5 EP11 Coprocessor (CEXxP)
+	  + Crypto Express 2 up to 7 Coprocessor (CEXxC)
+	  + Crypto Express 2 up to 7 Accelerator (CEXxA)
+	  + Crypto Express 4 up to 7 EP11 Coprocessor (CEXxP)
+
+config ZCRYPT_DEBUG
+	bool "Enable debug features for s390 cryptographic adapters"
+	default n
+	depends on DEBUG_KERNEL
+	depends on ZCRYPT
+	help
+	  Say 'Y' here to enable some additional debug features on the
+	  s390 cryptographic adapters driver.
+
+	  There will be some more sysfs attributes displayed for ap cards
+	  and queues and some flags on crypto requests are interpreted as
+	  debugging messages to force error injection.
+
+	  Do not enable on production level kernel build.
+
+	  If unsure, say N.
 
 config ZCRYPT_MULTIDEVNODES
 	bool "Support for multiple zcrypt device nodes"