Add new DFU string index to show device state

bootloader/src/nRF52840/usbd_device.cpp

@@ -39,6 +39,7 @@
 #include "deviceid_hal.h"
 #include "bytes2hexbuf.h"
 #include "platforms.h"
+#include "security_mode.h"
 
 using namespace particle::usbd;
 
@@ -194,6 +195,18 @@ char* device_id_as_string(char* buf) {
   return buf;
 }
 
+char* device_state_as_string(char* buf) {
+    int mode = security_mode_get(nullptr);
+
+    if (mode == MODULE_INFO_SECURITY_MODE_NONE) {
+      memcpy(buf, security_mode_is_overridden() ? "sm=s" : "sm=o", 4);
+    } else {
+      memcpy(buf, "sm=p", 4);
+    }
+
+    return buf;
+}
+
 } /* anonymous */
 
 dfu::DfuClassDriver g_dfuInstance(&NrfDevice::instance());
@@ -753,6 +766,11 @@ const uint8_t* NrfDevice::getString(SetupRequest* r, uint16_t* len) {
       /* No conversion to UTF-16 */
       return getUnicodeString(USBD_MsftStrDesc, sizeof(USBD_MsftStrDesc), len, true);
     }
+    case STRING_IDX_DEVICE_STATE: {
+      /* No conversion to UTF-16 */
+      char deviceStateStr[8] = {0};
+      return getUnicodeString(device_state_as_string(deviceStateStr), sizeof(deviceStateStr), len, false);
+    }
     default: {
       if (drv_) {
         bool conv = true;

bootloader/src/nRF52840/usbd_device.h

@@ -112,7 +112,8 @@ class Device {
     STRING_IDX_SERIAL       = 0x03,
     STRING_IDX_CONFIG       = 0x04,
     STRING_IDX_INTERFACE    = 0x05,
-    STRING_IDX_MSFT         = 0xee
+    STRING_IDX_MSFT         = 0xee,
+    STRING_IDX_DEVICE_STATE = 0xfa
   };
 
   enum Feature {

hal/src/rtl872x/usbd_device.cpp

@@ -26,6 +26,7 @@
 #include <algorithm>
 #include "appender.h"
 #include "device_code.h"
+#include "security_mode.h"
 
 using namespace particle::usbd;
 
@@ -49,6 +50,18 @@ char* device_id_as_string(char* buf) {
     return buf;
 }
 
+char* device_state_as_string(char* buf) {
+    int mode = security_mode_get(nullptr);
+
+    if (mode == MODULE_INFO_SECURITY_MODE_NONE) {
+      memcpy(buf, security_mode_is_overridden() ? "sm=s" : "sm=o", 4);
+    } else {
+      memcpy(buf, "sm=p", 4);
+    }
+
+    return buf;
+}
+
 /* MS OS String Descriptor */
 const uint8_t MSFT_STR_DESC[] = {
     USB_WCID_MS_OS_STRING_DESCRIPTOR(
@@ -358,6 +371,11 @@ int Device::getString(unsigned id, uint16_t langId, uint8_t* buf, size_t len) {
     case STRING_IDX_MSFT: {
         return getRawString((const char*)MSFT_STR_DESC, sizeof(MSFT_STR_DESC), buf, len);
     }
+    case STRING_IDX_DEVICE_STATE: {
+      /* No conversion to UTF-16 */
+      char deviceStateStr[8] = {0};
+      return getUnicodeString(device_state_as_string(deviceStateStr), sizeof(deviceStateStr), buf, len);
+    }
     default: {
         for (auto& cls: classDrivers_) {
             if (cls && cls->isEnabled()) {

hal/src/rtl872x/usbd_device.h

@@ -115,7 +115,8 @@ enum StringIndex {
     STRING_IDX_SERIAL = 0x03,
     STRING_IDX_CONFIG = 0x04,
     STRING_IDX_INTERFACE = 0x05,
-    STRING_IDX_MSFT = 0xee
+    STRING_IDX_MSFT = 0xee,
+    STRING_IDX_DEVICE_STATE = 0xfa
 };
 
 enum DeviceFeature {