K20 HIC waits until USB is configured to enable target power.

- Interface main function calls gpio_set_board_power() when USB
  is connected (really configured) and disconnected.
- The main task will wait ~2 seconds for USB to be configured. If this
  does not happen, it enables board power anyway. This is to support
  USB wall warts or similar power sources.
- Added gpio_set_board_power() to gpio.h.
- The K20 HIC implements this function to enable the target power switch
  only after high power has been negotiated with the USB host.
- gpio_set_board_power() is stubbed out for all other HICs.

source/daplink/interface/main.c

@@ -57,13 +57,17 @@
 #define FLAGS_MAIN_CDC_EVENT    (1 << 11)
 // Used by msd when flashing a new binary
 #define FLAGS_LED_BLINK_30MS    (1 << 6)
+
 // Timing constants (in 90mS ticks)
-// USB busy time
+// USB busy time (~3 sec)
 #define USB_BUSY_TIME           (33)
-// Delay before a USB device connect may occur
+// Delay before a USB device connect may occur (~1 sec)
 #define USB_CONNECT_DELAY       (11)
+// Timeout for USB being configured (~2 sec)
+#define USB_CONFIGURE_TIMEOUT   (22)
 // Delay before target may be taken out of reset or reprogrammed after startup
 #define STARTUP_DELAY           (1)
+
 // Decrement to zero
 #define DECZERO(x)              (x ? --x : 0)
 
@@ -209,6 +213,7 @@ __task void main_task(void)
     gpio_led_state_t msc_led_value = GPIO_LED_OFF;
     // USB
     uint32_t usb_state_count = USB_BUSY_TIME;
+    uint32_t usb_no_config_count = USB_CONFIGURE_TIMEOUT;
     // thread running after usb connected started
     uint8_t thread_started = 0;
     // button state
@@ -270,6 +275,8 @@ __task void main_task(void)
         if (flags & FLAGS_MAIN_POWERDOWN) {
             // Disable debug
             target_set_state(NO_DEBUG);
+            // Disable board power before USB is disconnected.
+            gpio_set_board_power(false);
             // Disconnect USB
             usbd_connect(0);
             // Turn off LED
@@ -302,15 +309,18 @@ __task void main_task(void)
             switch (usb_state) {
                 case USB_DISCONNECTING:
                     usb_state = USB_DISCONNECTED;
+                    // Disable board power before USB is disconnected.
+                    gpio_set_board_power(false);
                     usbd_connect(0);
                     break;
 
                 case USB_CONNECTING:
-
                     // Wait before connecting
                     if (DECZERO(usb_state_count) == 0) {
                         usbd_connect(1);
                         usb_state = USB_CHECK_CONNECTED;
+                        // Reset connect timeout
+                        usb_no_config_count = USB_CONFIGURE_TIMEOUT;
                     }
 
                     break;
@@ -322,8 +332,17 @@ __task void main_task(void)
                             thread_started = 1;
                         }
 
+                        // Let the HIC enable power to the target now that high power has been negotiated.
+                        gpio_set_board_power(true);
+
                         usb_state = USB_CONNECTED;
                     }
+                    else if (DECZERO(usb_no_config_count) == 0) {
+                        // USB configuration timed out, which most likely indicates that the HIC is
+                        // powered by a USB wall wart or similar power source. Go ahead and enable
+                        // board power.
+                        gpio_set_board_power(true);
+                    }
 
                     break;
 

source/hic_hal/atmel/sam3u2c/gpio.c

@@ -1,6 +1,6 @@
 /**
  * @file    gpio.c
- * @brief   
+ * @brief
  *
  * DAPLink Interface Firmware
  * Copyright (c) 2009-2016, ARM Limited, All Rights Reserved
@@ -36,7 +36,7 @@ void gpio_init(void)
     // Initially enable clock for GPIO and initialize LED ports as output with LED == off
     //
     PMC->PMC_PCER0 = (1 << 10) | (1 << 11) | (1 << 12);  // Enable clock for all PIOs
-    
+
     // DAP LED
     PIN_DAP_LED_PORT->PIO_PER = PIN_DAP_LED;
     PIN_DAP_LED_PORT->PIO_SODR = PIN_DAP_LED;
@@ -106,3 +106,7 @@ uint8_t gpio_get_sw_reset()
 {
     return (PIN_RESET_IN_FWRD_PORT->PIO_PDSR & PIN_RESET_IN_FWRD) != 0;
 }
+
+void gpio_set_board_power(bool powerEnabled)
+{
+}

source/hic_hal/freescale/k20dx/gpio.c

@@ -1,6 +1,6 @@
 /**
  * @file    gpio.c
- * @brief   
+ * @brief
  *
  * DAPLink Interface Firmware
  * Copyright (c) 2009-2016, ARM Limited, All Rights Reserved
@@ -57,16 +57,12 @@ void gpio_init(void)
     PIN_nRESET_GPIO->PDDR &= ~PIN_nRESET;
     PIN_nRESET_PORT->PCR[PIN_nRESET_BIT] = PORT_PCR_MUX(1);
 
-    // Keep powered off in bootloader mode
-    // to prevent the target from effecting the state
-    // of the reset line / reset button
-    if (!daplink_is_bootloader()) {
-        // configure pin as GPIO
-        PIN_POWER_EN_PORT->PCR[PIN_POWER_EN_BIT] = PORT_PCR_MUX(1);
-        // force always on logic 1
-        PIN_POWER_EN_GPIO->PDOR |= 1UL << PIN_POWER_EN_BIT;
-        PIN_POWER_EN_GPIO->PDDR |= 1UL << PIN_POWER_EN_BIT;
-    }
+    // configure pin as GPIO
+    PIN_POWER_EN_PORT->PCR[PIN_POWER_EN_BIT] = PORT_PCR_MUX(1);
+    // set output to 0
+    PIN_POWER_EN_GPIO->PCOR = PIN_POWER_EN;
+    // switch gpio to output
+    PIN_POWER_EN_GPIO->PDDR |= PIN_POWER_EN;
 
     // Let the voltage rails stabilize.  This is especailly important
     // during software resets, since the target's 3.3v rail can take
@@ -77,6 +73,18 @@ void gpio_init(void)
     busy_wait(1000000);
 }
 
+void gpio_set_board_power(bool powerEnabled)
+{
+    if (powerEnabled) {
+        // enable power switch
+        PIN_POWER_EN_GPIO->PSOR = PIN_POWER_EN;
+    }
+    else {
+        // disable power switch
+        PIN_POWER_EN_GPIO->PCOR = PIN_POWER_EN;
+    }
+}
+
 void gpio_set_hid_led(gpio_led_state_t state)
 {
     if (state) {

source/hic_hal/freescale/kl26z/gpio.c

@@ -1,6 +1,6 @@
 /**
  * @file    gpio.c
- * @brief   
+ * @brief
  *
  * DAPLink Interface Firmware
  * Copyright (c) 2009-2016, ARM Limited, All Rights Reserved
@@ -53,7 +53,7 @@ void gpio_init(void)
     PIN_POWER_EN_GPIO->PDDR |= PIN_POWER_EN;
     // set as input
     PIN_SW_RESET_GPIO->PDDR &= ~PIN_SW_RESET;
-    
+
     // Let the voltage rails stabilize.  This is especailly important
     // during software resets, since the target's 3.3v rail can take
     // 20-50ms to drain.  During this time the target could be driving
@@ -82,3 +82,7 @@ uint8_t gpio_get_sw_reset(void)
 {
     return (PIN_SW_RESET_GPIO->PDIR & PIN_SW_RESET) ? 1 : 0;
 }
+
+void gpio_set_board_power(bool powerEnabled)
+{
+}

source/hic_hal/gpio.h

@@ -1,6 +1,6 @@
 /**
  * @file    gpio.h
- * @brief   
+ * @brief
  *
  * DAPLink Interface Firmware
  * Copyright (c) 2009-2016, ARM Limited, All Rights Reserved
@@ -35,6 +35,7 @@ typedef enum led_state {
 } gpio_led_state_t;
 
 void gpio_init(void);
+void gpio_set_board_power(bool powerEnabled);
 void gpio_set_hid_led(gpio_led_state_t state);
 void gpio_set_cdc_led(gpio_led_state_t state);
 void gpio_set_msc_led(gpio_led_state_t state);

source/hic_hal/nxp/lpc11u35/gpio.c

@@ -1,6 +1,6 @@
 /**
  * @file    gpio.c
- * @brief   
+ * @brief
  *
  * DAPLink Interface Firmware
  * Copyright (c) 2009-2016, ARM Limited, All Rights Reserved
@@ -171,3 +171,7 @@ void target_forward_reset(bool assert_reset)
 {
     // Do nothing - reset is forwarded in gpio_get_sw_reset
 }
+
+void gpio_set_board_power(bool powerEnabled)
+{
+}

source/hic_hal/nxp/lpc4322/gpio.c

@@ -123,3 +123,7 @@ void target_forward_reset(bool assert_reset)
 {
     // Do nothing - reset is forwarded in gpio_get_sw_reset
 }
+
+void gpio_set_board_power(bool powerEnabled)
+{
+}