From a6ca5b82e7a1ecea61b77a771b0f4aa2545edf1a Mon Sep 17 00:00:00 2001
From: peabody124 <peabody124>
Date: Thu, 16 Sep 2010 20:23:02 +0000
Subject: [PATCH] OP-155 Flight/HID: Make the HID stall when buffer full.  Not
 sure the consequences on ground (i.e. if it handles the stall correctly)

git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@1665 ebee16cc-31ac-478f-84a7-5cbb03baadba
---
 flight/PiOS/STM32F10x/pios_usb_hid.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/flight/PiOS/STM32F10x/pios_usb_hid.c b/flight/PiOS/STM32F10x/pios_usb_hid.c
index c3a0408c9..4ee4bf6ce 100644
--- a/flight/PiOS/STM32F10x/pios_usb_hid.c
+++ b/flight/PiOS/STM32F10x/pios_usb_hid.c
@@ -284,7 +284,12 @@ int32_t PIOS_USB_HID_TxBufferPutMore(uint8_t id, const uint8_t *buffer, uint16_t
  */
 int32_t PIOS_USB_HID_RxBufferGet(uint8_t id)
 {
-	return bufferGetFromFront(&rxBuffer);
+	uint8_t read = bufferGetFromFront(&rxBuffer);
+	// If endpoint was stalled and there is now space make it valid
+	if((GetEPRxStatus(ENDP1) == EP_RX_STALL) && (bufferRemainingSpace(&rxBuffer) > 62)) {
+		SetEPRxStatus(ENDP1, EP_RX_VALID);
+	}	
+	return read;
 }
 
 /**
@@ -327,7 +332,13 @@ void PIOS_USB_HID_EP1_OUT_Callback(void)
 #else
 	bufferAddChunkToEnd(&rxBuffer, &rx_buffer[2], rx_buffer[1]);
 #endif
-	SetEPRxStatus(ENDP1, EP_RX_VALID);
+	
+	// Only reactivate endpoint if available space in buffer
+	if(bufferRemainingSpace(&rxBuffer) > 62) {
+		SetEPRxStatus(ENDP1, EP_RX_VALID);
+	} else {
+		SetEPRxStatus(ENDP1, EP_RX_STALL);
+	}
 }
 
 #endif