I2C low power updates

-Add timeout for staying in RUN mode after waking up or receiving I2C transaction
-Prevent entering sleep if I2C command is being processed
-Update power source when usb is attached/detached
-Don't process I2C Writes with nop cmd

source/board/microbitv2/IO_Config_Override.h

@@ -110,7 +110,7 @@ COMPILER_ASSERT(DAPLINK_HIC_ID == DAPLINK_HIC_ID_KL27Z);
 #define PIN_WAKE_ON_EDGE                    (1<<PIN_WAKE_ON_EDGE_BIT)
 #define PIN_WAKE_ON_EDGE_LLWU_PIN           (8)
 #define PIN_WAKE_ON_EDGE_LLWU_WAKEUP_TYPE   kLLWU_ExternalPinFallingEdge
-#define PIN_WAKE_ON_EDGE_PORT_WAKEUP_TYPE   kPORT_InterruptFallingEdge
+#define PIN_WAKE_ON_EDGE_PORT_WAKEUP_TYPE   kPORT_InterruptEitherEdge
 
 // Power LEDs
 

source/board/microbitv2/i2c.c

@@ -28,6 +28,9 @@ static i2cReadCallback_t pfReadCommsCallback = NULL;
 static i2cWriteCallback_t pfWriteFlashCallback = NULL;
 static i2cReadCallback_t pfReadFlashCallback = NULL;
 
+extern uint8_t i2c_wake_timeout;
+extern bool i2c_allow_sleep;
+
 static void i2c_slave_callback(I2C_Type *base, i2c_slave_transfer_t *xfer, void *userData) {
     switch (xfer->event)
     {
@@ -37,6 +40,7 @@ static void i2c_slave_callback(I2C_Type *base, i2c_slave_transfer_t *xfer, void
             xfer->dataSize = 0;
             // fsl_i2c.c IRQ updated in fsl_i2c_mod.c to include I2C D register
             address_match = *(uint8_t*)userData >> 1;
+            i2c_wake_timeout = 3;   // 3 * 30ms tick = 90ms timeout
             break;
         /*  Transmit request */
         case kI2C_SlaveTransmitEvent:
@@ -67,16 +71,21 @@ static void i2c_slave_callback(I2C_Type *base, i2c_slave_transfer_t *xfer, void
 
             // Default driver couldn't differentiate between RX or TX completion
             // Check flag set in kI2C_SlaveReceiveEvent
-
-            main_board_event();
+
+            // Ignore NOP cmd in I2C Write
+            if (!(g_SlaveRxFlag && g_slave_RX_buff[0] == 0x00)) {
+                main_board_event();
+            }
+
+            i2c_allow_sleep = false;
             break;
 
         default:
             g_SlaveCompletionFlag = false;
             break;
     }
 }
-
+// Hook function executed in the main task
 void board_custom_event() {
 
     if (g_SlaveRxFlag) {
@@ -94,6 +103,7 @@ void board_custom_event() {
             pfReadFlashCallback(&g_slave_TX_buff[0], transferredCount);
         }
     }
+    i2c_allow_sleep = true;
 }
 
 static void i2c_init_pins(void) {

source/board/microbitv2/microbitv2.c

@@ -250,21 +250,24 @@ void board_30ms_hook()
         main_shutdown_state = MAIN_SHUTDOWN_REQUESTED;
     }
 
-    if (prev_usb_state != usb_state) {
-        power_source = pwr_mon_get_power_source();
+    if (wake_from_usb) {
+        main_shutdown_state = MAIN_USER_EVENT;
+
+        if (usb_state == USB_DISCONNECTED) {
+            usb_state = USB_CONNECTING;
+        }
+    }
+
+    if (i2c_wake_timeout > 0) {
+        i2c_wake_timeout--;
     }
-    prev_usb_state = usb_state;
 
     // Enter light sleep if USB is not enumerated and main_shutdown_state is idle
     if (usb_state == USB_DISCONNECTED && !usb_pc_connected && main_shutdown_state == MAIN_SHUTDOWN_WAITING 
-        && automatic_sleep_on == true && g_s_handle.isBusy == false) { 
+        && automatic_sleep_on == true && g_s_handle.isBusy == false && i2c_wake_timeout == 0 && i2c_allow_sleep) { 
         interface_power_mode = kAPP_PowerModeVlps;
         main_shutdown_state = MAIN_SHUTDOWN_REQUESTED;
     }
-
-    if (wake_from_usb) {
-        main_shutdown_state = MAIN_SHUTDOWN_ALERT;
-    }
 
     switch (main_shutdown_state) {
       case MAIN_LED_FULL_BRIGHTNESS:
@@ -319,7 +322,7 @@ void board_30ms_hook()
           main_shutdown_state = MAIN_SHUTDOWN_WAITING;
           }
           break;
-      case MAIN_SHUTDOWN_ALERT:
+      case MAIN_USER_EVENT:
           {
           // Release COMBINED_SENSOR_INT in case it was previously asserted
           PORT_SetPinMux(COMBINED_SENSOR_INT_PORT, COMBINED_SENSOR_INT_PIN, kPORT_PinDisabledOrAnalog);
@@ -758,7 +761,7 @@ static void i2c_write_comms_callback(uint8_t* pData, uint8_t size) {
         break;
         default:
             i2cResponse.cmdId = gErrorResponse_c;
-            i2cResponse.cmdData.errorRspCmd.errorCode = gErrorUnknownProperty_c;
+            i2cResponse.cmdData.errorRspCmd.errorCode = gErrorUnknownCommand_c;
         break;
     }
 

source/board/microbitv2/power.c

@@ -11,8 +11,10 @@
 
 #include "main.h"
 #include "power.h"
+#include "pwr_mon.h"
 #include "IO_Config.h"
 #include "uart.h"
+#include "i2c.h"
 #include "rl_usb.h"
 
 /*******************************************************************************
@@ -28,6 +30,7 @@ extern volatile uint8_t wake_from_reset;
 extern volatile uint8_t wake_from_usb;
 extern volatile bool usb_pc_connected;
 extern main_usb_connect_t usb_state;
+extern power_source_t power_source;
 
 /*******************************************************************************
  * Code
@@ -59,8 +62,12 @@ void PORTCD_IRQHandler(void)
     if ((1U << PIN_WAKE_ON_EDGE_BIT) & PORT_GetPinsInterruptFlags(PIN_WAKE_ON_EDGE_PORT))
     {
         PORT_ClearPinsInterruptFlags(PIN_WAKE_ON_EDGE_PORT, (1U << PIN_WAKE_ON_EDGE_BIT));
+
+        power_source = pwr_mon_get_power_source();
 
-        if ((PIN_WAKE_ON_EDGE_PORT->PCR[PIN_WAKE_ON_EDGE_BIT] & PORT_PCR_IRQC_MASK) == PORT_PCR_IRQC(kPORT_InterruptRisingEdge)) {
+        bool usb_on = (((PIN_WAKE_ON_EDGE_GPIO->PDIR) >> PIN_WAKE_ON_EDGE_BIT) & 0x01U) ? false : true;
+
+        if (usb_on == false) {
             /* Reset USB on cable detach (VBUS falling edge) */
             USBD_Reset();
             usbd_reset_core();
@@ -91,8 +98,8 @@ void power_init(void)
     /* Disable USB voltage regulator */
     SIM->SOPT1 &= ~SIM_SOPT1_USBREGEN_MASK;
 
-    /* Enable rising edge interrupt on WAKE_ON_EDGE pin (VBUS falling edge) to detect USB detach */
-    PORT_SetPinInterruptConfig(PIN_WAKE_ON_EDGE_PORT, PIN_WAKE_ON_EDGE_BIT, kPORT_InterruptRisingEdge);
+    /* Enable either edge interrupt on WAKE_ON_EDGE pin to detect USB attach/detach */
+    PORT_SetPinInterruptConfig(PIN_WAKE_ON_EDGE_PORT, PIN_WAKE_ON_EDGE_BIT, PIN_WAKE_ON_EDGE_PORT_WAKEUP_TYPE);
 
     NVIC_SetPriority(LLWU_IRQn, (1UL << __NVIC_PRIO_BITS) - 1UL);
     NVIC_EnableIRQ(LLWU_IRQn);
@@ -128,7 +135,6 @@ static void power_enter_mode(app_power_mode_t targetPowerMode)
 static void power_set_wakeup_config(app_power_mode_t targetMode)
 {
     PORT_SetPinInterruptConfig(PIN_SW_RESET_PORT, PIN_SW_RESET_BIT, PIN_SW_RESET_PORT_WAKEUP_TYPE);
-    PORT_SetPinInterruptConfig(PIN_WAKE_ON_EDGE_PORT, PIN_WAKE_ON_EDGE_BIT, PIN_WAKE_ON_EDGE_PORT_WAKEUP_TYPE);
 
     /* If targetMode is VLLS/LLS, setup LLWU. */
     if ((kAPP_PowerModeWait != targetMode) && (kAPP_PowerModeVlpw != targetMode) &&
@@ -197,7 +203,6 @@ static void power_pre_switch_hook(smc_power_state_t originPowerState, app_power_
 
 static void power_post_switch_hook(smc_power_state_t originPowerState, app_power_mode_t targetMode)
 {
-
     /* Configure I/O pin SWCLK */
     PIN_SWCLK_PORT->PCR[PIN_SWCLK_BIT] = PORT_PCR_MUX(1)  | /* GPIO */
                                          PORT_PCR_PE_MASK;  /* Pull (Down) enable */
@@ -213,7 +218,6 @@ static void power_post_switch_hook(smc_power_state_t originPowerState, app_power
     PORT_SetPinMux(UART_PORT, PIN_UART_TX_BIT, (port_mux_t)PIN_UART_TX_MUX_ALT);
 
     uart_initialize();
-
-    /* Change to rising edge interrupt on WAKE_ON_EDGE pin (VBUS falling edge) to detect USB detach */
-    PORT_SetPinInterruptConfig(PIN_WAKE_ON_EDGE_PORT, PIN_WAKE_ON_EDGE_BIT, kPORT_InterruptRisingEdge);
+    i2c_deinitialize();
+    i2c_initialize();
 }