Disable SPI, I²C, touch controller and display controller in sleep mode.

Re-enable them on wake up.

Remove delays that were not needed in st7889 driver.

Hopefully, it'll improve the battery life!

src/Components/Gfx/Gfx.cpp

@@ -85,4 +85,12 @@ void Gfx::pixel_draw(uint8_t x, uint8_t y, uint16_t color) {
   lcd.DrawPixel(x, y, color);
 }
 
+void Gfx::Sleep() {
+  lcd.Sleep();
+}
+
+void Gfx::Wakeup() {
+  lcd.Wakeup();
+}
+
 

src/Components/Gfx/Gfx.h

@@ -16,6 +16,9 @@ namespace Pinetime {
         void DrawChar(const FONT_INFO *font, uint8_t c, uint8_t *x, uint8_t y, uint16_t color);
         void FillRectangle(uint8_t x, uint8_t y, uint8_t width, uint8_t height, uint16_t color);
 
+        void Sleep();
+        void Wakeup();
+
       private:
         Drivers::St7789& lcd;
         const uint8_t width = 240;

src/DisplayApp/DisplayApp.cpp

@@ -136,9 +136,14 @@ void DisplayApp::Refresh() {
         vTaskDelay(100);
         nrf_gpio_pin_set(14);
         lcd->DisplayOff();
+        lcd->Sleep();
+        touchPanel.Sleep();
         state = States::Idle;
         break;
       case Messages::GoToRunning:
+        lcd->Wakeup();
+        touchPanel.Wakeup();
+
         lcd->DisplayOn();
         nrf_gpio_pin_clear(23);
         nrf_gpio_pin_clear(22);

src/drivers/Cst816s.cpp

@@ -75,3 +75,13 @@ Cst816S::TouchInfos Cst816S::GetTouchInfo() {
   info.action = action;
   return info;
 }
+
+void Cst816S::Sleep() {
+  nrfx_twi_disable(&twi);
+  nrf_gpio_cfg_default(6);
+  nrf_gpio_cfg_default(7);
+}
+
+void Cst816S::Wakeup() {
+  Init();
+}

src/drivers/Cst816s.h

@@ -19,6 +19,8 @@ namespace Pinetime {
         void Init();
         void Probe();
         TouchInfos GetTouchInfo();
+        void Sleep();
+        void Wakeup();
       private:
         static constexpr uint8_t pinIrq = 28;
         static constexpr uint8_t pinReset = 10;

src/drivers/SpiMaster.cpp

@@ -4,6 +4,9 @@
 using namespace Pinetime::Drivers;
 
 bool SpiMaster::Init(const SpiMaster::SpiModule spi, const SpiMaster::Parameters &params) {
+  configSpiModule = spi;
+  configParams = params;
+
   /* Configure GPIO pins used for pselsck, pselmosi, pselmiso and pselss for SPI0 */
   nrf_gpio_cfg_output(params.pinSCK);
   nrf_gpio_cfg_output(params.pinMOSI);
@@ -86,3 +89,17 @@ bool SpiMaster::Write(const uint8_t *data, size_t size) {
 
   return true;
 }
+
+void SpiMaster::Sleep() {
+  while(NRF_SPI0->ENABLE != 0) {
+    NRF_SPI0->ENABLE = (SPIM_ENABLE_ENABLE_Disabled << SPIM_ENABLE_ENABLE_Pos);
+  }
+  nrf_gpio_cfg_default(configParams.pinSCK);
+  nrf_gpio_cfg_default(configParams.pinMOSI);
+  nrf_gpio_cfg_default(configParams.pinMISO);
+  nrf_gpio_cfg_default(configParams.pinCSN);
+}
+
+void SpiMaster::Wakeup() {
+  Init(configSpiModule, configParams);
+}

src/drivers/SpiMaster.h

@@ -23,9 +23,15 @@ namespace Pinetime {
         bool Init(const SpiModule spi, const Parameters& params);
         bool Write(const uint8_t* data, size_t size);
 
+        void Sleep();
+        void Wakeup();
+
       private:
         NRF_SPI_Type *  spiBaseAddress;
         uint8_t pinCsn;
+
+        SpiMaster::SpiModule configSpiModule;
+        SpiMaster::Parameters configParams;
     };
   }
 }

src/drivers/St7789.cpp

@@ -48,7 +48,10 @@ void St7789::SoftwareReset() {
 
 void St7789::SleepOut() {
   WriteCommand(static_cast<uint8_t>(Commands::SleepOut));
-  nrf_delay_ms(500);
+}
+
+void St7789::SleepIn() {
+  WriteCommand(static_cast<uint8_t>(Commands::SleepIn));
 }
 
 void St7789::ColMod() {
@@ -90,7 +93,6 @@ void St7789::NormalModeOn() {
 
 void St7789::DisplayOn() {
   WriteCommand(static_cast<uint8_t>(Commands::DisplayOn));
-  nrf_delay_ms(500);
 }
 
 void St7789::FillRectangle(uint16_t x, uint16_t y, uint16_t width, uint16_t height, uint16_t color) {
@@ -163,9 +165,30 @@ void St7789::NextDrawBuffer(const uint8_t *data, size_t size) {
 
 void St7789::HardwareReset() {
   nrf_gpio_pin_clear(26);
-  nrf_delay_ms(200);
+  nrf_delay_ms(10);
   nrf_gpio_pin_set(26);
+}
 
+void St7789::Sleep() {
+  SleepIn();
+  nrf_gpio_cfg_default(pinDataCommand);
+  spi.Sleep();
+}
+
+void St7789::Wakeup() {
+  spi.Wakeup();
+
+  nrf_gpio_cfg_output(pinDataCommand);
+  // TODO why do we need to reset the controller?
+  SoftwareReset();
+  SleepOut();
+  ColMod();
+  MemoryDataAccessControl();
+  ColumnAddressSet();
+  RowAddressSet();
+  DisplayInversionOn();
+  NormalModeOn();
+  DisplayOn();
 }
 
 

src/drivers/St7789.h

@@ -19,6 +19,9 @@ namespace Pinetime {
         void DisplayOn();
         void DisplayOff();
 
+        void Sleep();
+        void Wakeup();
+
 
       private:
         SpiMaster& spi;
@@ -27,6 +30,7 @@ namespace Pinetime {
         void HardwareReset();
         void SoftwareReset();
         void SleepOut();
+        void SleepIn();
         void ColMod();
         void MemoryDataAccessControl();
         void DisplayInversionOn();
@@ -41,6 +45,7 @@ namespace Pinetime {
 
         enum class Commands : uint8_t {
           SoftwareReset = 0x01,
+          SleepIn = 0x10,
           SleepOut = 0x11,
           NormalModeOn = 0x13,
           DisplayInversionOn = 0x21,