tracing: gpio: Add Kconfig option for enabling/disabling trace events

Add a new options to trace Kconfig, CONFIG_TRACING_EVENTS_GPIO, that is
used for enabling/disabling compilation of gpio function trace events.

Link: http://lkml.kernel.org/r/1438432079-11704-4-git-send-email-tal.shorer@gmail.com

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Tal Shorer <tal.shorer@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/include/trace/events/gpio.h b/include/trace/events/gpio.h
index 927a8ad..2da73b9 100644
--- a/include/trace/events/gpio.h
+++ b/include/trace/events/gpio.h
@@ -1,6 +1,10 @@
 #undef TRACE_SYSTEM
 #define TRACE_SYSTEM gpio
 
+#ifndef CONFIG_TRACING_EVENTS_GPIO
+#define NOTRACE
+#endif
+
 #if !defined(_TRACE_GPIO_H) || defined(TRACE_HEADER_MULTI_READ)
 #define _TRACE_GPIO_H
 
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 1153c43..8d6363f 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -635,6 +635,13 @@
 
 	If unsure, say N
 
+config TRACING_EVENTS_GPIO
+	bool "Trace gpio events"
+	depends on GPIOLIB
+	default y
+	help
+	  Enable tracing events for gpio subsystem
+
 endif # FTRACE
 
 endif # TRACING_SUPPORT