add CTS local time characteristic and use it to provide UTC in DateTimeController

src/components/ble/CurrentTimeClient.cpp

@@ -85,21 +85,11 @@ int CurrentTimeClient::OnCurrentTimeReadResult(uint16_t conn_handle, const ble_g
     // TODO check that attribute->handle equals the handle discovered in OnCharacteristicDiscoveryEvent
     CtsData result;
     os_mbuf_copydata(attribute->om, 0, sizeof(CtsData), &result);
-    NRF_LOG_INFO("Received data: %d-%d-%d %d:%d:%d",
+    uint16_t year = ((uint16_t) result.year_MSO << 8) + result.year_LSO;
-                 result.year,
+
-                 result.month,
+    NRF_LOG_INFO("Received data: %d-%d-%d %d:%d:%d", year, result.month, result.dayofmonth, result.hour, result.minute, result.second);
-                 result.dayofmonth,
+    dateTimeController
-                 result.hour,
+      .SetTime(year, result.month, result.dayofmonth, 0, result.hour, result.minute, result.second, nrf_rtc_counter_get(portNRF_RTC_REG));
-                 result.minute,
-                 result.second);
-    dateTimeController.SetTime(result.year,
-                               result.month,
-                               result.dayofmonth,
-                               0,
-                               result.hour,
-                               result.minute,
-                               result.second,
-                               nrf_rtc_counter_get(portNRF_RTC_REG));
   } else {
     NRF_LOG_INFO("Error retrieving current time: %d", error->status);
   }

src/components/ble/CurrentTimeClient.h

@@ -29,14 +29,16 @@ namespace Pinetime {
 
     private:
       typedef struct __attribute__((packed)) {
-        uint16_t year;
+        uint8_t year_LSO; // explicit byte ordering to be independent of machine order
+        uint8_t year_MSO; // BLE GATT is little endian
         uint8_t month;
         uint8_t dayofmonth;
         uint8_t hour;
         uint8_t minute;
         uint8_t second;
-        uint8_t millis;
+        uint8_t dayofweek;
-        uint8_t reason;
+        uint8_t fractions256; // currently ignored
+        uint8_t reason;       // currently ignored, not that any host would set it anyway
       } CtsData;
 
       static constexpr uint16_t ctsServiceId {0x1805};

src/components/ble/CurrentTimeService.cpp

@@ -5,11 +5,23 @@
 using namespace Pinetime::Controllers;
 
 constexpr ble_uuid16_t CurrentTimeService::ctsUuid;
-constexpr ble_uuid16_t CurrentTimeService::ctChrUuid;
+constexpr ble_uuid16_t CurrentTimeService::ctsCtChrUuid;
+constexpr ble_uuid16_t CurrentTimeService::ctsLtChrUuid;
 
 int CTSCallback(uint16_t conn_handle, uint16_t attr_handle, struct ble_gatt_access_ctxt* ctxt, void* arg) {
   auto cts = static_cast<CurrentTimeService*>(arg);
-  return cts->OnTimeAccessed(conn_handle, attr_handle, ctxt);
+
+  return cts->OnCurrentTimeServiceAccessed(conn_handle, attr_handle, ctxt);
+}
+
+int CurrentTimeService::OnCurrentTimeServiceAccessed(uint16_t conn_handle, uint16_t attr_handle, struct ble_gatt_access_ctxt* ctxt) {
+  switch (ble_uuid_u16(ctxt->chr->uuid)) {
+    case ctsCurrentTimeCharId:
+      return OnCurrentTimeAccessed(conn_handle, attr_handle, ctxt);
+    case ctsLocalTimeCharId:
+      return OnLocalTimeAccessed(conn_handle, attr_handle, ctxt);
+  }
+  return -1; // Unknown characteristic
 }
 
 void CurrentTimeService::Init() {
@@ -18,45 +30,69 @@ void CurrentTimeService::Init() {
   ASSERT(res == 0);
 
   res = ble_gatts_add_svcs(serviceDefinition);
+
   ASSERT(res == 0);
 }
 
-int CurrentTimeService::OnTimeAccessed(uint16_t conn_handle, uint16_t attr_handle, struct ble_gatt_access_ctxt* ctxt) {
+int CurrentTimeService::OnCurrentTimeAccessed(uint16_t conn_handle, uint16_t attr_handle, struct ble_gatt_access_ctxt* ctxt) {
 
   NRF_LOG_INFO("Setting time...");
 
   if (ctxt->op == BLE_GATT_ACCESS_OP_WRITE_CHR) {
-    CtsData result;
+    CtsCurrentTimeData result;
-    os_mbuf_copydata(ctxt->om, 0, sizeof(CtsData), &result);
+    int res = os_mbuf_copydata(ctxt->om, 0, sizeof(CtsCurrentTimeData), &result);
+    if (res < 0) {
+      NRF_LOG_ERROR("Error reading BLE Data writing to CTS Current Time (too little data)")
+      return BLE_ATT_ERR_INVALID_ATTR_VALUE_LEN;
+    }
 
-    NRF_LOG_INFO("Received data: %d-%d-%d %d:%d:%d",
+    uint16_t year = ((uint16_t) result.year_MSO << 8) + result.year_LSO;
-                 result.year,
-                 result.month,
-                 result.dayofmonth,
-                 result.hour,
-                 result.minute,
-                 result.second);
 
-    m_dateTimeController.SetTime(result.year,
+    NRF_LOG_INFO("Received data: %d-%d-%d %d:%d:%d", year, result.month, result.dayofmonth, result.hour, result.minute, result.second);
-                                 result.month,
+
-                                 result.dayofmonth,
+    m_dateTimeController
-                                 0,
+      .SetTime(year, result.month, result.dayofmonth, 0, result.hour, result.minute, result.second, nrf_rtc_counter_get(portNRF_RTC_REG));
-                                 result.hour,
-                                 result.minute,
-                                 result.second,
-                                 nrf_rtc_counter_get(portNRF_RTC_REG));
 
   } else if (ctxt->op == BLE_GATT_ACCESS_OP_READ_CHR) {
-    CtsData currentDateTime;
+    CtsCurrentTimeData currentDateTime;
-    currentDateTime.year = m_dateTimeController.Year();
+    currentDateTime.year_LSO = m_dateTimeController.Year() & 0xff;
+    currentDateTime.year_MSO = (m_dateTimeController.Year() >> 8) & 0xff;
     currentDateTime.month = static_cast<u_int8_t>(m_dateTimeController.Month());
     currentDateTime.dayofmonth = m_dateTimeController.Day();
     currentDateTime.hour = m_dateTimeController.Hours();
     currentDateTime.minute = m_dateTimeController.Minutes();
     currentDateTime.second = m_dateTimeController.Seconds();
-    currentDateTime.millis = 0;
+    currentDateTime.fractions256 = 0;
 
-    int res = os_mbuf_append(ctxt->om, &currentDateTime, sizeof(CtsData));
+    int res = os_mbuf_append(ctxt->om, &currentDateTime, sizeof(CtsCurrentTimeData));
+    return (res == 0) ? 0 : BLE_ATT_ERR_INSUFFICIENT_RES;
+  }
+
+  return 0;
+}
+
+int CurrentTimeService::OnLocalTimeAccessed(uint16_t conn_handle, uint16_t attr_handle, struct ble_gatt_access_ctxt* ctxt) {
+  NRF_LOG_INFO("Setting timezone...");
+
+  if (ctxt->op == BLE_GATT_ACCESS_OP_WRITE_CHR) {
+    CtsLocalTimeData result;
+    int res = os_mbuf_copydata(ctxt->om, 0, sizeof(CtsLocalTimeData), &result);
+
+    if (res < 0) {
+      NRF_LOG_ERROR("Error reading BLE Data writing to CTS Local Time (too little data)")
+      return BLE_ATT_ERR_INVALID_ATTR_VALUE_LEN;
+    }
+
+    NRF_LOG_INFO("Received data: %d %d", result.timezone, result.dst);
+
+    m_dateTimeController.SetTimeZone(result.timezone, result.dst);
+
+  } else if (ctxt->op == BLE_GATT_ACCESS_OP_READ_CHR) {
+    CtsLocalTimeData currentTimezone;
+    currentTimezone.timezone = m_dateTimeController.TzOffset();
+    currentTimezone.dst = m_dateTimeController.DstOffset();
+
+    int res = os_mbuf_append(ctxt->om, &currentTimezone, sizeof(currentTimezone));
     return (res == 0) ? 0 : BLE_ATT_ERR_INSUFFICIENT_RES;
   }
 
@@ -64,12 +100,19 @@ int CurrentTimeService::OnTimeAccessed(uint16_t conn_handle, uint16_t attr_handl
 }
 
 CurrentTimeService::CurrentTimeService(DateTime& dateTimeController)
-  : characteristicDefinition {{.uuid = &ctChrUuid.u,
+  : characteristicDefinition {
-                               .access_cb = CTSCallback,
 
+                              {.uuid = &ctsLtChrUuid.u,
+                               .access_cb = CTSCallback,
                                .arg = this,
                                .flags = BLE_GATT_CHR_F_WRITE | BLE_GATT_CHR_F_READ},
-                              {0}},
+
+                               {.uuid = &ctsCtChrUuid.u,
+                               .access_cb = CTSCallback,
+                               .arg = this,
+                               .flags = BLE_GATT_CHR_F_WRITE | BLE_GATT_CHR_F_READ},
+
+                               {0}},
     serviceDefinition {
       {/* Device Information Service */
        .type = BLE_GATT_SVC_TYPE_PRIMARY,

src/components/ble/CurrentTimeService.h

@@ -16,29 +16,40 @@ namespace Pinetime {
       CurrentTimeService(DateTime& dateTimeController);
       void Init();
 
-      int OnTimeAccessed(uint16_t conn_handle, uint16_t attr_handle, struct ble_gatt_access_ctxt* ctxt);
+      int OnCurrentTimeServiceAccessed(uint16_t conn_handle, uint16_t attr_handle, struct ble_gatt_access_ctxt* ctxt);
+      int OnCurrentTimeAccessed(uint16_t conn_handle, uint16_t attr_handle, struct ble_gatt_access_ctxt* ctxt);
+      int OnLocalTimeAccessed(uint16_t conn_handle, uint16_t attr_handle, struct ble_gatt_access_ctxt* ctxt);
 
     private:
       static constexpr uint16_t ctsId {0x1805};
-      static constexpr uint16_t ctsCharId {0x2a2b};
+      static constexpr uint16_t ctsCurrentTimeCharId {0x2a2b};
+      static constexpr uint16_t ctsLocalTimeCharId {0x2a0f};
 
       static constexpr ble_uuid16_t ctsUuid {.u {.type = BLE_UUID_TYPE_16}, .value = ctsId};
 
-      static constexpr ble_uuid16_t ctChrUuid {.u {.type = BLE_UUID_TYPE_16}, .value = ctsCharId};
+      static constexpr ble_uuid16_t ctsCtChrUuid {.u {.type = BLE_UUID_TYPE_16}, .value = ctsCurrentTimeCharId};
+      static constexpr ble_uuid16_t ctsLtChrUuid {.u {.type = BLE_UUID_TYPE_16}, .value = ctsLocalTimeCharId};
 
-      struct ble_gatt_chr_def characteristicDefinition[2];
+      struct ble_gatt_chr_def characteristicDefinition[3];
       struct ble_gatt_svc_def serviceDefinition[2];
 
       typedef struct __attribute__((packed)) {
-        uint16_t year;
+        uint8_t year_LSO; // BLE GATT is little endian
+        uint8_t year_MSO;
         uint8_t month;
         uint8_t dayofmonth;
         uint8_t hour;
         uint8_t minute;
         uint8_t second;
-        uint8_t millis;
+        uint8_t dayofweek;
-        uint8_t reason;
+        uint8_t fractions256; // currently ignored
-      } CtsData;
+        uint8_t reason;       // currently ignored, not that any host would set it anyway
+      } CtsCurrentTimeData;
+
+      typedef struct __attribute__((packed)) {
+        uint8_t timezone;
+        uint8_t dst;
+      } CtsLocalTimeData;
 
       DateTime& m_dateTimeController;
     };

src/components/datetime/DateTimeController.cpp

@@ -36,6 +36,7 @@ void DateTime::SetTime(uint16_t year,
     /* .tm_mon  = */ month - 1,
     /* .tm_year = */ year - 1900,
   };
+
   tm.tm_isdst = -1; // Use DST value from local time zone
   currentDateTime = std::chrono::system_clock::from_time_t(std::mktime(&tm));
 
@@ -50,6 +51,11 @@ void DateTime::SetTime(uint16_t year,
   systemTask->PushMessage(System::Messages::OnNewTime);
 }
 
+void DateTime::SetTimeZone(uint8_t timezone, uint8_t dst) {
+  tzOffset = timezone;
+  dstOffset = dst;
+}
+
 void DateTime::UpdateTime(uint32_t systickCounter) {
   // Handle systick counter overflow
   uint32_t systickDelta = 0;

src/components/datetime/DateTimeController.h

@@ -38,6 +38,18 @@ namespace Pinetime {
                    uint8_t minute,
                    uint8_t second,
                    uint32_t systickCounter);
+
+      /*
+       * setter corresponding to the BLE Set Local Time characteristic.
+       *
+       * used to update difference between utc and local time (see UtcOffset())
+       *
+       * parameters are in quarters of an our. Following the BLE CTS specification,
+       * timezone is expected to be constant over DST which will be reported in
+       * dst field.
+       */
+      void SetTimeZone(uint8_t timezone, uint8_t dst);
+
       void UpdateTime(uint32_t systickCounter);
       uint16_t Year() const {
         return year;
@@ -61,6 +73,42 @@ namespace Pinetime {
         return second;
       }
 
+      /*
+       * returns the offset between local time and UTC in quarters of an hour
+       *
+       * Availability of this field depends on wether the companion app
+       * supports the BLE CTS Local Time Characteristic. Expect it to be 0
+       * if not.
+       */
+      uint8_t UtcOffset() const {
+        return tzOffset + dstOffset;
+      }
+
+      /*
+       * returns the offset between the (dst independent) local time zone and UTC
+       * in quarters of an hour
+       *
+       * Availability of this field depends on wether the companion app
+       * supports the BLE CTS Local Time Characteristic. Expect it to be 0
+       * if not.
+       */
+      uint8_t TzOffset() const {
+        return tzOffset;
+      }
+
+      /*
+       * returns the offset between the local time zone and local time
+       * in quarters of an hour
+       * if != 0, DST is in effect, if == 0 not.
+       *
+       * Availability of this field depends on wether the companion app
+       * supports the BLE CTS Local Time Characteristic. Expect it to be 0
+       * if not.
+       */
+      uint8_t DstOffset() const {
+        return dstOffset;
+      }
+
       const char* MonthShortToString() const;
       const char* DayOfWeekShortToString() const;
       static const char* MonthShortToStringLow(Months month);
@@ -69,6 +117,9 @@ namespace Pinetime {
       std::chrono::time_point<std::chrono::system_clock, std::chrono::nanoseconds> CurrentDateTime() const {
         return currentDateTime;
       }
+      std::chrono::time_point<std::chrono::system_clock, std::chrono::nanoseconds> UTCDateTime() const {
+        return currentDateTime - std::chrono::seconds((tzOffset + dstOffset) * 15 * 60);
+      }
       std::chrono::seconds Uptime() const {
         return uptime;
       }
@@ -85,6 +136,8 @@ namespace Pinetime {
       uint8_t hour = 0;
       uint8_t minute = 0;
       uint8_t second = 0;
+      uint8_t tzOffset = 0;
+      uint8_t dstOffset = 0;
 
       uint32_t previousSystickCounter = 0;
       std::chrono::time_point<std::chrono::system_clock, std::chrono::nanoseconds> currentDateTime;