From 42332fc46e838e83eb42c2cff50b23e092dfb7f1 Mon Sep 17 00:00:00 2001
From: Markus Sattler <help.markus+git@gmail.com>
Date: Sat, 25 Jul 2015 09:22:37 +0200
Subject: [PATCH] allow user to run code in user_rf_pre_init. add void to "C"
 functions.

example:
extern "C" void __run_user_rf_pre_init(void) {
    system_phy_set_rfoption(2);
}

see: #515 and #413
---
 cores/esp8266/Esp.h              |  2 +-
 cores/esp8266/core_esp8266_phy.c | 16 ++++++++++++----
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/cores/esp8266/Esp.h b/cores/esp8266/Esp.h
index 8e66f8f88..17349f688 100644
--- a/cores/esp8266/Esp.h
+++ b/cores/esp8266/Esp.h
@@ -68,7 +68,7 @@ enum ADCMode {
     ADC_VDD = 255
 };
 
-#define ADC_MODE(mode) extern "C" int __get_adc_mode() { return (int) (mode); }
+#define ADC_MODE(mode) extern "C" int __get_adc_mode(void) { return (int) (mode); }
 
 typedef enum {
      FM_QIO = 0x00,
diff --git a/cores/esp8266/core_esp8266_phy.c b/cores/esp8266/core_esp8266_phy.c
index cc624ade0..e24a933aa 100644
--- a/cores/esp8266/core_esp8266_phy.c
+++ b/cores/esp8266/core_esp8266_phy.c
@@ -247,18 +247,26 @@ void user_rf_pre_init() {
     rtc_reg[30] = 0;
 
     system_set_os_print(0);
+    __run_user_rf_pre_init();
 }
 
-extern int __get_rf_mode()  __attribute__((weak));
-extern int __get_rf_mode()
+extern int __get_rf_mode(void)  __attribute__((weak));
+extern int __get_rf_mode(void)
 {
     return 0;  // default mode
 }
 
-extern int __get_adc_mode() __attribute__((weak));
-extern int __get_adc_mode()
+extern int __get_adc_mode(void) __attribute__((weak));
+extern int __get_adc_mode(void)
 {
     return 33; // default ADC mode
 }
 
+extern void __run_user_rf_pre_init(void) __attribute__((weak));
+extern void __run_user_rf_pre_init(void)
+{
+    return; // default do noting
+}
+
+