[PATCH 3/8] powerpc/rtas: rtas_call_unlocked() kerneldoc

[Nathan Lynch via B4 Relay <devnull+nathanl.linux.ibm.com@kernel.org>]

From: Nathan Lynch <nathanl@linux.ibm.com>

Add documentation for rtas_call_unlocked(), including details on how
it differs from rtas_call().

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
---
 arch/powerpc/kernel/rtas.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index 9256cfaa8b6f..c73b01d722f6 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -1016,6 +1016,23 @@ va_rtas_call_unlocked(struct rtas_args *args, int token, int nargs, int nret,
 	do_enter_rtas(args);
 }
 
+/**
+ * rtas_call_unlocked() - Invoke an RTAS firmware function without synchronization.
+ * @args: RTAS parameter block to be used for the call, must obey RTAS addressing
+ *        constraints.
+ * @token: Identifies the function being invoked.
+ * @nargs: Number of input parameters. Does not include token.
+ * @nret: Number of output parameters, including the call status.
+ * @....: List of @nargs input parameters.
+ *
+ * Invokes the RTAS function indicated by @token, which the caller
+ * should obtain via rtas_function_token().
+ *
+ * This function is similar to rtas_call(), but must be used with a
+ * limited set of RTAS calls specifically exempted from the general
+ * requirement that only one RTAS call may be in progress at any
+ * time. Examples include stop-self and ibm,nmi-interlock.
+ */
 void rtas_call_unlocked(struct rtas_args *args, int token, int nargs, int nret, ...)
 {
 	va_list list;

-- 
2.39.1