[PATCH] random: Document add_hwgenerator_randomness() with other input functions

[Mark Brown]

The section at the top of random.c which documents the input functions
available does not document add_hwgenerator_randomness() which might lead
a reader to overlook it. Add a brief note about it.

Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
 drivers/char/random.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 0d10e31fd342..ba2dc45bf718 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -228,6 +228,14 @@
  * particular randomness source.  They do this by keeping track of the
  * first and second order deltas of the event timings.
  *
+ * There is also an interface for true hardware RNGs:
+ *
+ *	void add_hwgenerator_randomness(const char *buffer, size_t count,
+ *				size_t entropy);
+ *
+ * This will credit entropy as specified by the caller, if the entropy
+ * pool is full it will block until more entropy is needed.
+ *
  * Ensuring unpredictability at system startup
  * ============================================
  *
-- 
2.20.1