add remote wakeup for HIDKeyboard

no key report in wakeup

Author: DeqingSun

ch55xduino/ch55x/libraries/Generic_Examples/examples/05.USB/HidKeyboard/src/userUsbHidKeyboard/USBHIDKeyboard.c

@@ -205,6 +205,11 @@ uint8_t USB_EP1_send() {
 }
 
 uint8_t Keyboard_press(__data uint8_t k) {
+  if (USB_RemoteWakeup()) {
+    // Don't register this key press - it was used for wakeup
+    return 0;
+  }
+
   __data uint8_t i;
   if (k >= 136) { // it's a non-printing key (not a modifier)
     k = k - 136;

ch55xduino/ch55x/libraries/Generic_Examples/examples/05.USB/HidKeyboard/src/userUsbHidKeyboard/USBconstant.c

@@ -38,7 +38,8 @@ __code USB_Descriptor_Configuration_t ConfigurationDescriptor = {
                .ConfigurationNumber = 1,
                .ConfigurationStrIndex = NO_DESCRIPTOR,
 
-               .ConfigAttributes = (USB_CONFIG_ATTR_RESERVED),
+               .ConfigAttributes =
+                   (USB_CONFIG_ATTR_RESERVED | USB_CONFIG_ATTR_REMOTEWAKEUP),
 
                .MaxPowerConsumption = USB_CONFIG_POWER_MA(200)},
 

ch55xduino/ch55x/libraries/Generic_Examples/examples/05.USB/HidKeyboard/src/userUsbHidKeyboard/USBhandler.c

@@ -33,6 +33,10 @@ __xdata uint8_t keyboardProtocol = 1;
 
 __xdata uint8_t keyboardLedStatus = 0;
 
+// Track USB suspend state for remote wakeup
+volatile __bit usbSuspended = 0;
+
+void delayMicroseconds(__data uint16_t us);
 inline void NOP_Process(void) {}
 
 void USB_EP0_SETUP() {
@@ -472,15 +476,16 @@ void USBInterrupt(void) { // inline not really working in multiple files in SDCC
   if (UIF_SUSPEND) {
     UIF_SUSPEND = 0;
     if (USB_MIS_ST & bUMS_SUSPEND) { // Suspend
-
+      usbSuspended = 1;              // Mark USB as suspended
+      // Optionally put MCU to sleep here if needed
       // while ( XBUS_AUX & bUART0_TX );                    // Wait for Tx
       // SAFE_MOD = 0x55;
       // SAFE_MOD = 0xAA;
       // WAKE_CTRL = bWAK_BY_USB | bWAK_RXD0_LO;    // Wake up by USB or RxD0
       // PCON |= PD; // Chip sleep SAFE_MOD = 0x55; SAFE_MOD = 0xAA; WAKE_CTRL =
       // 0x00;
-
-    } else {             // Unexpected interrupt, not supposed to happen !
+    } else {             // Resume
+      usbSuspended = 0;  // USB is active again
       USB_INT_FG = 0xFF; // Clear interrupt flag
     }
   }
@@ -537,3 +542,21 @@ void USBDeviceEndPointCfg() {
       UEP_R_RES_ACK | UEP_T_RES_NAK; // Manual flip, OUT transaction returns
                                      // ACK, IN transaction returns NAK
 }
+
+// Trigger USB remote wakeup to wake host from suspend
+// Returns 1 if wakeup was performed, 0 if not needed
+uint8_t USB_RemoteWakeup() {
+  if (usbSuspended && (ConfigurationDescriptor.Config.ConfigAttributes &
+                       USB_CONFIG_ATTR_REMOTEWAKEUP)) {
+    // Send resume signal: force DP/DM output resume/K state
+    // The Usb was running at full speed 12M mode
+
+    UDEV_CTRL |= bUD_LOW_SPEED;
+    delayMicroseconds(50000);
+    UDEV_CTRL &= ~bUD_LOW_SPEED;
+    usbSuspended = 0; // Mark as no longer suspended
+    delayMicroseconds(50000);
+    return 1; // Wakeup was performed
+  }
+  return 0; // No wakeup needed
+}

ch55xduino/ch55x/libraries/Generic_Examples/examples/05.USB/HidKeyboard/src/userUsbHidKeyboard/USBhandler.h

@@ -18,6 +18,9 @@ extern __data uint8_t SetupReq;
 volatile extern __xdata uint8_t UsbConfig;
 
 extern const __code uint8_t *__data pDescr;
+extern __xdata uint8_t keyboardProtocol;
+extern __xdata uint8_t keyboardLedStatus;
+extern volatile __bit usbSuspended;
 
 void USB_EP1_IN();
 void USB_EP1_OUT();
@@ -56,5 +59,7 @@ void USBInterrupt(void);
 void USBDeviceCfg();
 void USBDeviceIntCfg();
 void USBDeviceEndPointCfg();
+uint8_t
+USB_RemoteWakeup(); // Trigger remote wakeup, returns 1 if wakeup was performed
 
 #endif