crypto: nx - add NX-842 platform frontend driver

Add NX-842 frontend that allows using either the pSeries platform or
PowerNV platform driver (to be added by later patch) for the NX-842
hardware.  Update the MAINTAINERS file to include the new filenames.
Update Kconfig files to clarify titles and descriptions, and correct
dependencies.

Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/drivers/crypto/nx/nx-842.h b/drivers/crypto/nx/nx-842.h
new file mode 100644
index 0000000..2a5d4e1
--- /dev/null
+++ b/drivers/crypto/nx/nx-842.h
@@ -0,0 +1,32 @@
+
+#ifndef __NX_842_H__
+#define __NX_842_H__
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/nx842.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+
+struct nx842_driver {
+	struct module *owner;
+
+	int (*compress)(const unsigned char *in, unsigned int in_len,
+			unsigned char *out, unsigned int *out_len,
+			void *wrkmem);
+	int (*decompress)(const unsigned char *in, unsigned int in_len,
+			  unsigned char *out, unsigned int *out_len,
+			  void *wrkmem);
+};
+
+void nx842_register_driver(struct nx842_driver *driver);
+void nx842_unregister_driver(struct nx842_driver *driver);
+
+
+/* To allow the main nx-compress module to load platform module */
+#define NX842_PSERIES_MODULE_NAME	"nx-compress-pseries"
+#define NX842_PSERIES_COMPAT_NAME	"ibm,compression"
+
+
+#endif /* __NX_842_H__ */