Improves firmware version check

Adds granularity and allows usage of newer firmware with current driver.

Author: Veijo Pesonen

ESP8266/ESP8266.cpp

@@ -32,6 +32,8 @@ ESP8266::ESP8266(PinName tx, PinName rx, bool debug, PinName rts, PinName cts)
       _parser(&_serial),
       _packets(0),
       _packets_end(&_packets),
+      _sdk_v(-1,-1,-1),
+      _at_v(-1,-1,-1),
       _connect_error(0),
       _fail(false),
       _closed(false),
@@ -67,22 +69,45 @@ bool ESP8266::at_available()
     return ready;
 }
 
-int ESP8266::get_firmware_version()
+struct ESP8266::fw_sdk_version ESP8266::sdk_version()
 {
-    int version;
+    int major;
+    int minor;
+    int patch;
 
     _smutex.lock();
-    bool done = _parser.send("AT+GMR")
-           && _parser.recv("SDK version:%d", &version)
-           && _parser.recv("OK\n");
+    bool done = _parser.send("AT+GMR");
+    done &= _parser.recv("SDK version:%d.%d.%d", &major, &minor, &patch);
+    done &= _parser.recv("OK\n");
+    _smutex.unlock();
+
+    if(done) {
+        _sdk_v.major = major;
+        _sdk_v.minor = minor;
+        _sdk_v.patch = patch;
+    }
+    return _sdk_v;
+}
+
+struct ESP8266::fw_at_version ESP8266::at_version()
+{
+    int major;
+    int minor;
+    int patch;
+    int nused;
+
+    _smutex.lock();
+    bool done = _parser.send("AT+GMR");
+    done &= _parser.recv("AT version:%d.%d.%d.%d", &major, &minor, &patch, &nused);
+    done &= _parser.recv("OK\n");
     _smutex.unlock();
 
     if(done) {
-        return version;
-    } else { 
-        // Older firmware versions do not prefix the version with "SDK version: "
-        return -1;
+        _at_v.major = major;
+        _at_v.minor = minor;
+        _at_v.patch = patch;
     }
+    return _at_v;
 }
 
 bool ESP8266::stop_uart_hw_flow_ctrl(void)

ESP8266/ESP8266.h

@@ -43,6 +43,34 @@ class ESP8266
 public:
     ESP8266(PinName tx, PinName rx, bool debug=false, PinName rts=NC, PinName cts=NC);
 
+    /**
+    * ESP8266 firmware SDK version
+    *
+    * @param major Major version number
+    * @param minor Minor version number
+    * @param patch Patch version number
+    */
+    struct fw_sdk_version {
+        int major;
+        int minor;
+        int patch;
+        fw_sdk_version (int major, int minor, int patch) : major(major), minor(minor), patch(patch) {}
+    };
+
+    /**
+    * ESP8266 firmware AT version
+    *
+    * @param major Major version number
+    * @param minor Minor version number
+    * @param patch Patch version number
+    */
+    struct fw_at_version {
+        int major;
+        int minor;
+        int patch;
+        fw_at_version (int major, int minor, int patch) : major(major), minor(minor), patch(patch) {}
+    };
+
     /**
     * Check AT command interface of ESP8266
     *
@@ -51,12 +79,19 @@ class ESP8266
     bool at_available(void);
 
     /**
-    * Check firmware version of ESP8266
+    * Check sdk version from which firmware is created
     *
-    * @return integer firmware version or -1 if firmware query command gives outdated response
+    * @return fw_sdk_version which tells major, minor and patch version
     */
-    int get_firmware_version(void);
-    
+    struct fw_sdk_version sdk_version(void);
+
+    /**
+    * Check AT instruction set version from which firmware is created
+    *
+    * @return fw_at_version which tells major, minor and patch version
+    */
+    struct fw_at_version at_version(void);
+
     /**
     * Startup the ESP8266
     *
@@ -305,6 +340,9 @@ class ESP8266
         uint32_t alloc_len; // Original length
         // data follows
     } *_packets, **_packets_end;
+
+    struct fw_sdk_version _sdk_v;
+    struct fw_at_version _at_v;
     void _packet_handler();
     void _connect_error_handler();
     bool recv_ap(nsapi_wifi_ap_t *ap);

ESP8266Interface.cpp

@@ -38,7 +38,8 @@
 #endif
 
 // Firmware version
-#define ESP8266_VERSION 2
+#define ESP8266_SDK_VERSION_MAJOR 2
+#define ESP8266_AT_VERSION_MAJOR 1
 
 ESP8266Interface::ESP8266Interface()
     : _esp(MBED_CONF_ESP8266_TX, MBED_CONF_ESP8266_RX, MBED_CONF_ESP8266_DEBUG, MBED_CONF_ESP8266_RTS, MBED_CONF_ESP8266_CTS),
@@ -239,9 +240,16 @@ int ESP8266Interface::scan(WiFiAccessPoint *res, unsigned count)
 
 bool ESP8266Interface::_get_firmware_ok()
 {
-    if (_esp.get_firmware_version() < ESP8266_VERSION) {
-        debug("ESP8266: ERROR: Firmware incompatible with this driver.\
-               \r\nUpdate at least to v%d - https://developer.mbed.org/teams/ESP8266/wiki/Firmware-Update\r\n",ESP8266_VERSION);
+    ESP8266::fw_at_version at_v = _esp.at_version();
+    if (at_v.major < ESP8266_AT_VERSION_MAJOR) {
+        debug("ESP8266: ERROR: AT Firmware v%d incompatible with this driver.", at_v.major);
+        debug("Update at least to v%d - https://developer.mbed.org/teams/ESP8266/wiki/Firmware-Update\n", ESP8266_AT_VERSION_MAJOR);
+        return false;
+    }
+    ESP8266::fw_sdk_version sdk_v = _esp.sdk_version();
+    if (sdk_v.major < ESP8266_SDK_VERSION_MAJOR) {
+        debug("ESP8266: ERROR: Firmware v%d incompatible with this driver.", sdk_v.major);
+        debug("Update at least to v%d - https://developer.mbed.org/teams/ESP8266/wiki/Firmware-Update\n", ESP8266_SDK_VERSION_MAJOR);
         return false;
     }