Updates to GADC to use new simpler gfx queued bufferring.

NOTE: code is still buggy (or the one and only driver is buggy).

4 files changed, 173 insertions, 219 deletions

diff --git a/src/gadc/driver.h b/src/gadc/driver.h
index 4427f4f0..6e935576 100644
--- a/src/gadc/driver.h
+++ b/src/gadc/driver.h
@@ -32,9 +32,9 @@
  * @{
  */
 typedef struct GadcLldTimerData_t {
-	uint32_t		physdev;		/* @< A value passed to describe which physical ADC devices/channels to use. */
-	adcsample_t		*buffer;		/* @< The static buffer to put the ADC samples into. */
-	size_t			count;			/* @< The number of conversions to do before doing a callback and stopping the ADC. */
+	uint32_t		physdev;		/* @< Which physical ADC devices/channels to use. Filled in by High Level Code */
+	uint32_t		frequency;		/* @< The conversion frequency. Filled in by High Level Code */
+	GDataBuffer		*pdata;			/* @< The buffer to put the ADC samples into. */
 	bool_t			now;			/* @< Trigger the first conversion now rather than waiting for the first timer interrupt (if possible) */
 	} GadcLldTimerData;
 /* @} */
@@ -52,30 +52,6 @@ typedef struct GadcLldNonTimerData_t {
 /* @} */
 
 /**
- * @brief				These routines are the callbacks that the driver uses.
- * @details				Defined in the high level GADC code.
- *
- * @notapi
- * @{
- */
-
-/**
- * @param[in] adcp		The ADC driver
- * @param[in] buffer	The sample buffer
- * @param[in] n			The amount of samples
- */
-extern void GADC_ISR_CompleteI(ADCDriver *adcp, adcsample_t *buffer, size_t n);
-
-/**
- * @param[in] adcp 		The ADC driver
- * @param[in] err 		ADC error
- */
-extern void GADC_ISR_ErrorI(ADCDriver *adcp, adcerror_t err);
-/**
- * @}
- */
-
-/**
  * @brief				This can be incremented by the low level driver if a timer interrupt is missed.
  * @details				Defined in the high level GADC code.
  *
@@ -92,70 +68,75 @@ extern "C" {
 #endif
 
 /**
- * @brief				Initialise the driver
+ * @brief				These routines are the callbacks that the driver uses.
+ * @details				Defined in the high level GADC code.
  *
- * @api
+ * @notapi
+ * @{
+ */
+	/**
+	 * @brief	The last conversion requested is now complete
+	 */
+	void gadcDataReadyI(void);
+
+	/**
+	 * @brief	The last conversion requested failed
+	 */
+	void gadcDataFailI(void);
+/**
+ * @}
  */
-void gadc_lld_init(void);
 
 /**
- * @brief				Get the number of samples in a conversion.
- * @details				Calculates and returns the number of samples per conversion for the specified physdev.
- *
- * @note				A physdev describing a mono device would return 1, a stereo device would return 2.
- * 						For most ADC's physdev is a bitmap so it is only a matter of counting the bits.
- *
- * @param[in] physdev	A value passed to describe which physical ADC devices/channels to use.
+ * @brief				Initialise the driver
  *
- * @return				Number of samples of the convesion
  * @api
  */
-size_t gadc_lld_samples_per_conversion(uint32_t physdev);
+void gadc_lld_init(void);
 
 /**
  * @brief				Start a periodic timer for high frequency conversions.
  *
- * @param[in] physdev		A value passed to describe which physical ADC devices/channels to use.
- * @param[in] frequency		The frequency to create ADC conversions
+ * @param[in] pgtd		The structure containing the sample frequency and physical device to use.
  *
  * @note				The exact meaning of physdev is hardware dependent. It describes the channels
  * 						the will be used later on when a "timer" conversion is actually scheduled.
  * @note				It is assumed that the timer is capable of free-running even when the ADC
  * 						is stopped or doing something else.
- * @details				When a timer interrupt occurs a conversion should start if these is a "timer" conversion
+ * @details				When a timer interrupt occurs a conversion should start if there is a "timer" conversion
  * 						active.
- * @note				If the ADC is stopped, doesn't have a "timer" conversion active or is currently executing
- * 						a non-timer conversion then the interrupt can be ignored other than (optionally) incrementing
+ * @note				Timer interrupts occurring before @p gadc_lld_adc_timerI() has been called,
+ * 						if  @p gadc_lld_adc_timerI() has been called quick enough, or while
+ * 						a non-timer conversion is active should be ignored other than (optionally) incrementing
  * 						the GADC_Timer_Missed variable.
+ * @note				The pdata and now members of the pgtd structure are now yet valid.
  *
  * @api
  */
-void gadc_lld_start_timer(uint32_t physdev, uint32_t frequency);
+void gadc_lld_start_timer(GadcLldTimerData *pgtd);
 
 /**
  * @brief				Stop the periodic timer for high frequency conversions.
  * @details				Also stops any current "timer" conversion (but not a current "non-timer" conversion).
  *
- * @param[in] physdev	A value passed to describe which physical ADC devices/channels in use.
- *
- * @note				The exact meaning of physdev is hardware dependent.
+ * @param[in] pgtd		The structure containing the sample frequency and physical device to use.
  *
+ * @note				After this function returns there should be no more calls to @p gadcDataReadyI()
+ * 						or @p gadcDataFailI() in relation to timer conversions.
  * @api
  */
-void gadc_lld_stop_timer(uint32_t physdev);
+void gadc_lld_stop_timer(GadcLldTimerData *pgtd);
 
 /**
- * @brief				Start a "timer" conversion.
+ * @brief				Start a set of "timer" conversions.
  * @details				Starts a series of conversions triggered by the timer.
  *
  * @param[in] pgtd		Contains the parameters for the timer conversion.
  *
  * @note				The exact meaning of physdev is hardware dependent. It is likely described in the
  * 						drivers gadc_lld_config.h
- * @note				Some versions of ChibiOS actually call the callback function more than once, once
- * 						at the half-way point and once on completion. The high level code handles this.
- * @note				The driver should call @p GADC_ISR_CompleteI() when it completes the operation
- * 						(or at the half-way point), or @p GAD_ISR_ErrorI() on an error.
+ * @note				The driver should call @p gadcDataReadyI() when it completes the operation
+ * 						or @p gadcDataFailI() on an error.
  * @note				The high level code ensures that this is not called while a non-timer conversion is in
  * 						progress
  *
@@ -171,8 +152,8 @@ void gadc_lld_adc_timerI(GadcLldTimerData *pgtd);
  *
  * @note				The exact meaning of physdev is hardware dependent. It is likely described in the
  * 						drivers gadc_lld_config.h
- * @note				The driver should call @p GADC_ISR_CompleteI() when it completes the operation
- * 						or @p GAD_ISR_ErrorI() on an error.
+ * @note				The driver should call @p gadcDataReadyI() when it completes the operation
+ * 						or @p gadcDataFailI() on an error.
  * @note				The high level code ensures that this is not called while a timer conversion is in
  * 						progress
  *
diff --git a/src/gadc/gadc.c b/src/gadc/gadc.c
index 8ae431b0..e2d2d461 100644
--- a/src/gadc/gadc.c
+++ b/src/gadc/gadc.c
@@ -31,42 +31,30 @@
 
 volatile bool_t GADC_Timer_Missed;
 
-static gfxSem	gadcsem;
-static gfxMutex	gadcmutex;
-static GTimer	LowSpeedGTimer;
+static bool_t			gadcRunning;
+static gfxSem			LowSpeedSlotSem;
+static gfxMutex			LowSpeedMutex;
+static GTimer			LowSpeedGTimer;
+static gfxQueueGSync	HighSpeedBuffers;
+
 #if GFX_USE_GEVENT
-	static GTimer	HighSpeedGTimer;
+	static GTimer		HighSpeedGTimer;
 #endif
 
-static volatile uint16_t	gflags = 0;
-	#define GADC_GFLG_ISACTIVE	0x0001
 
 #define GADC_FLG_ISACTIVE	0x0001
 #define GADC_FLG_ISDONE		0x0002
 #define GADC_FLG_ERROR		0x0004
 #define GADC_FLG_GTIMER		0x0008
+#define GADC_FLG_STALLED	0x0010
 
 static struct hsdev {
 	// Our status flags
 	uint16_t				flags;
 
-	// What we started with
-	uint32_t				frequency;
-	adcsample_t				*buffer;
-	size_t					bufcount;
-	size_t					samplesPerEvent;
-
-	// The last set of results
-	size_t					lastcount;
-	adcsample_t				*lastbuffer;
-	uint16_t				lastflags;
-
 	// Other stuff we need to track progress and for signaling
 	GadcLldTimerData		lld;
-	size_t					samplesPerConversion;
-	size_t					remaining;
-	gfxSem					*bsem;
-	GEventADC				*pEvent;
+	uint16_t				eventflags;
 	GADCISRCallbackFunction	isrfn;
 	} hs;
 
@@ -101,49 +89,59 @@ static inline void FindNextConversionI(void) {
 	/**
 	 * Look for the next thing to do.
 	 */
-	while(curlsdev < &ls[GADC_MAX_LOWSPEED_DEVICES]) {
+	gadcRunning = TRUE;
+	for(; curlsdev < &ls[GADC_MAX_LOWSPEED_DEVICES]; curlsdev++) {
 		if ((curlsdev->flags & (GADC_FLG_ISACTIVE|GADC_FLG_ISDONE)) == GADC_FLG_ISACTIVE) {
 			gadc_lld_adc_nontimerI(&curlsdev->lld);
 			return;
 		}
-		curlsdev++;
 	}
 	curlsdev = 0;
 
 	/* No more low speed devices - do a high speed conversion */
 	if (hs.flags & GADC_FLG_ISACTIVE) {
-		hs.lld.now = GADC_Timer_Missed ? TRUE : FALSE;
-		GADC_Timer_Missed = 0;
-		gadc_lld_adc_timerI(&hs.lld);
-		return;
+		hs.lld.pdata = gfxBufferGetI();
+		if (hs.lld.pdata) {
+			hs.lld.now = GADC_Timer_Missed || (hs.flags & GADC_FLG_STALLED);
+			hs.flags &= ~GADC_FLG_STALLED;
+			GADC_Timer_Missed = 0;
+			gadc_lld_adc_timerI(&hs.lld);
+			return;
+		}
+
+		// Oops - no free buffers - mark stalled and go back to low speed devices
+		hs.flags |= GADC_FLG_STALLED;
+		hs.eventflags &= ~GADC_HSADC_RUNNING;
+		for(curlsdev = ls; curlsdev < &ls[GADC_MAX_LOWSPEED_DEVICES]; curlsdev++) {
+			if ((curlsdev->flags & (GADC_FLG_ISACTIVE|GADC_FLG_ISDONE)) == GADC_FLG_ISACTIVE) {
+				gadc_lld_adc_nontimerI(&curlsdev->lld);
+				return;
+			}
+		}
+		curlsdev = 0;
 	}
 
 	/* Nothing more to do */
-	gflags &= ~GADC_GFLG_ISACTIVE;
+	gadcRunning = FALSE;
 }
 
-void GADC_ISR_CompleteI(ADCDriver *adcp, adcsample_t *buffer, size_t n) {
-	(void) adcp;
+void gadcDataReadyI(void) {
 
 	if (curlsdev) {
 		/* This interrupt must be in relation to the low speed device */
 
 		if (curlsdev->flags & GADC_FLG_ISACTIVE) {
-			/**
-			 * As we only handle a single low speed conversion at a time, we know
-			 * we know we won't get any half completion interrupts.
-			 */
 			curlsdev->flags |= GADC_FLG_ISDONE;
 			gtimerJabI(&LowSpeedGTimer);
 		}
 
-		#if ADC_ISR_FULL_CODE_BUG
+		#if GFX_USE_OS_CHIBIOS && CHIBIOS_ADC_ISR_FULL_CODE_BUG
 			/**
 			 * Oops - We have just finished a low speed conversion but a bug prevents us
 			 * restarting the ADC here. Other code will restart it in the thread based
 			 * ADC handler.
 			 */
-			gflags &= ~GADC_GFLG_ISACTIVE;
+			gadcRunning = FALSE;
 			return;
 
 		#endif
@@ -152,49 +150,31 @@ void GADC_ISR_CompleteI(ADCDriver *adcp, adcsample_t *buffer, size_t n) {
 		/* This interrupt must be in relation to the high speed device */
 
 		if (hs.flags & GADC_FLG_ISACTIVE) {
-			/* Save the details */
-			hs.lastcount = n;
-			hs.lastbuffer = buffer;
-			hs.lastflags = GADC_Timer_Missed ? GADC_HSADC_LOSTEVENT : 0;
+			if (hs.lld.pdata->len) {
+				/* Save the current buffer on the HighSpeedBuffers */
+				gfxQueueGSyncPutI(&HighSpeedBuffers, (gfxQueueGSyncItem *)hs.lld.pdata);
+				hs.lld.pdata = 0;
+
+				/* Save the details */
+				hs.eventflags = GADC_HSADC_RUNNING|GADC_HSADC_GOTBUFFER;
+				if (GADC_Timer_Missed)
+					hs.eventflags |= GADC_HSADC_LOSTEVENT;
+				if (hs.flags & GADC_FLG_STALLED)
+					hs.eventflags |= GADC_HSADC_STALL;
+
+				/* Our signalling mechanisms */
+				if (hs.isrfn)
+					hs.isrfn();
 
-			/* Signal the user with the data */
-			if (hs.pEvent) {
 				#if GFX_USE_GEVENT
-					hs.pEvent->type = GEVENT_ADC;
+					if (hs.flags & GADC_FLG_GTIMER)
+						gtimerJabI(&HighSpeedGTimer);
 				#endif
-				hs.pEvent->count = hs.lastcount;
-				hs.pEvent->buffer = hs.lastbuffer;
-				hs.pEvent->flags = hs.lastflags;
-			}
-
-			/* Our three signalling mechanisms */
-			if (hs.isrfn)
-				hs.isrfn(buffer, n);
-
-			if (hs.bsem)
-				gfxSemSignalI(hs.bsem);
-
-			#if GFX_USE_GEVENT
-				if (hs.flags & GADC_FLG_GTIMER)
-					gtimerJabI(&HighSpeedGTimer);
-			#endif
-
-			/* Adjust what we have left to do */
-			hs.lld.count -= n;
-			hs.remaining -= n;
-
-			/* Half completion - We have done all we can for now - wait for the next interrupt */
-			if (hs.lld.count)
-				return;
-
-			/* Our buffer is cyclic - set up the new buffer pointers */
-			if (hs.remaining) {
-				hs.lld.buffer = buffer + (n * hs.samplesPerConversion);
 			} else {
-				hs.remaining = hs.bufcount;
-				hs.lld.buffer = hs.buffer;
+				// Oops - no data in this buffer. Just return it to the free-list
+				gfxBufferRelease(hs.lld.pdata);
+				hs.lld.pdata = 0;
 			}
-			hs.lld.count = hs.remaining < hs.samplesPerEvent ? hs.remaining : hs.samplesPerEvent;
 		}
 	}
 
@@ -204,22 +184,19 @@ void GADC_ISR_CompleteI(ADCDriver *adcp, adcsample_t *buffer, size_t n) {
 	FindNextConversionI();
 }
 
-void GADC_ISR_ErrorI(ADCDriver *adcp, adcerror_t err) {
-	(void) adcp;
-	(void) err;
-
+void gadcDataFailI(void) {
 	if (curlsdev) {
 		if ((curlsdev->flags & (GADC_FLG_ISACTIVE|GADC_FLG_ISDONE)) == GADC_FLG_ISACTIVE)
 			/* Mark the error then try to repeat it */
 			curlsdev->flags |= GADC_FLG_ERROR;
 
-		#if ADC_ISR_FULL_CODE_BUG
+		#if GFX_USE_OS_CHIBIOS && CHIBIOS_ADC_ISR_FULL_CODE_BUG
 			/**
 			 * Oops - We have just finished a low speed conversion but a bug prevents us
 			 * restarting the ADC here. Other code will restart it in the thread based
 			 * ADC handler.
 			 */
-			gflags &= ~GADC_GFLG_ISACTIVE;
+			gadcRunning = FALSE;
 			gtimerJabI(&LowSpeedGTimer);
 			return;
 
@@ -239,8 +216,9 @@ void GADC_ISR_ErrorI(ADCDriver *adcp, adcerror_t err) {
 void _gadcInit(void)
 {
 	gadc_lld_init();
-	gfxSemInit(&gadcsem, GADC_MAX_LOWSPEED_DEVICES, GADC_MAX_LOWSPEED_DEVICES);
-	gfxMutexInit(&gadcmutex);
+	gfxQueueGSyncInit(&HighSpeedBuffers);
+	gfxSemInit(&LowSpeedSlotSem, GADC_MAX_LOWSPEED_DEVICES, GADC_MAX_LOWSPEED_DEVICES);
+	gfxMutexInit(&LowSpeedMutex);
 	gtimerInit(&LowSpeedGTimer);
 	#if GFX_USE_GEVENT
 		gtimerInit(&HighSpeedGTimer);
@@ -252,8 +230,9 @@ void _gadcDeinit(void)
 	/* commented stuff is ToDo */
 
 	// gadc_lld_deinit();
-	gfxSemDestroy(&gadcsem);
-	gfxMutexDestroy(&gadcmutex);
+	gfxQueueGSyncDeinit(&HighSpeedBuffers);
+	gfxSemDestroy(&LowSpeedSlotSem);
+	gfxMutexDestroy(&LowSpeedMutex);
 	gtimerDeinit(&LowSpeedGTimer);
 	#if GFX_USE_GEVENT
 		gtimerDeinit(&HighSpeedGTimer);
@@ -262,7 +241,7 @@ void _gadcDeinit(void)
 
 static inline void StartADC(bool_t onNoHS) {
 	gfxSystemLock();
-	if (!(gflags & GADC_GFLG_ISACTIVE) || (onNoHS && !curlsdev))
+	if (!gadcRunning || (onNoHS && !curlsdev))
 		FindNextConversionI();
 	gfxSystemUnlock();
 }
@@ -289,9 +268,7 @@ static void BSemSignalCallback(adcsample_t *buffer, void *param) {
 			}
 
 			pe->type = GEVENT_ADC;
-			pe->count = hs.lastcount;
-			pe->buffer = hs.lastbuffer;
-			pe->flags = hs.lastflags | psl->srcflags;
+			pe->flags = hs.eventflags | psl->srcflags;
 			psl->srcflags = 0;
 			geventSendEvent(psl);
 		}
@@ -305,7 +282,7 @@ static void LowSpeedGTimerCallback(void *param) {
 	adcsample_t				*buffer;
 	struct lsdev			*p;
 
-	#if ADC_ISR_FULL_CODE_BUG
+	#if GFX_USE_OS_CHIBIOS && CHIBIOS_ADC_ISR_FULL_CODE_BUG
 		/* Ensure the ADC is running if it needs to be - Bugfix HACK */
 		StartADC(FALSE);
 	#endif
@@ -325,33 +302,22 @@ static void LowSpeedGTimerCallback(void *param) {
 			p->param = 0;			// Needed to prevent the compiler removing the local variables
 			p->lld.buffer = 0;		// Needed to prevent the compiler removing the local variables
 			p->flags = 0;			// The slot is available (indivisible operation)
-			gfxSemSignal(&gadcsem);	// Tell everyone
+			gfxSemSignal(&LowSpeedSlotSem);	// Tell everyone
 			fn(buffer, prm);		// Perform the callback
 		}
 	}
 
 }
 
-void gadcHighSpeedInit(uint32_t physdev, uint32_t frequency, adcsample_t *buffer, size_t bufcount, size_t samplesPerEvent)
+void gadcHighSpeedInit(uint32_t physdev, uint32_t frequency)
 {
 	gadcHighSpeedStop();		/* This does the init for us */
 
 	/* Just save the details and reset everything for now */
-	hs.frequency = frequency;
-	hs.buffer = buffer;
-	hs.bufcount = bufcount;
-	hs.samplesPerEvent = samplesPerEvent;
-	hs.lastcount = 0;
-	hs.lastbuffer = 0;
-	hs.lastflags = 0;
 	hs.lld.physdev = physdev;
-	hs.lld.buffer = buffer;
-	hs.lld.count = samplesPerEvent;
+	hs.lld.frequency = frequency;
+	hs.lld.pdata = 0;
 	hs.lld.now = FALSE;
-	hs.samplesPerConversion = gadc_lld_samples_per_conversion(physdev);
-	hs.remaining = bufcount;
-	hs.bsem = 0;
-	hs.pEvent = 0;
 	hs.isrfn = 0;
 }
 
@@ -368,12 +334,12 @@ void gadcHighSpeedSetISRCallback(GADCISRCallbackFunction isrfn) {
 	hs.isrfn = isrfn;
 }
 
-void gadcHighSpeedSetBSem(gfxSem *pbsem, GEventADC *pEvent) {
-	/* Use the system lock to ensure they occur atomically */
-	gfxSystemLock();
-	hs.pEvent = pEvent;
-	hs.bsem = pbsem;
-	gfxSystemUnlock();
+GDataBuffer *gadcHighSpeedGetData(delaytime_t ms) {
+	return (GDataBuffer *)gfxQueueGSyncGet(&HighSpeedBuffers, ms);
+}
+
+GDataBuffer *gadcHighSpeedGetDataI(void) {
+	return (GDataBuffer *)gfxQueueGSyncGetI(&HighSpeedBuffers);
 }
 
 void gadcHighSpeedStart(void) {
@@ -381,8 +347,8 @@ void gadcHighSpeedStart(void) {
 	if (hs.flags & GADC_FLG_ISACTIVE)
 		return;
 
-	gadc_lld_start_timer(hs.lld.physdev, hs.frequency);
 	hs.flags = GADC_FLG_ISACTIVE;
+	gadc_lld_start_timer(&hs.lld);
 	StartADC(FALSE);
 }
 
@@ -390,7 +356,15 @@ void gadcHighSpeedStop(void) {
 	if (hs.flags & GADC_FLG_ISACTIVE) {
 		/* No more from us */
 		hs.flags = 0;
-		gadc_lld_stop_timer(hs.lld.physdev);
+		gadc_lld_stop_timer(&hs.lld);
+		/*
+		 * There might be a buffer still locked up by the driver - if so release it.
+		 */
+		if (hs.lld.pdata) {
+			gfxBufferRelease(hs.lld.pdata);
+			hs.lld.pdata = 0;
+		}
+
 		/*
 		 * We have to pass TRUE to StartADC() as we might have the ADC marked as active when it isn't
 		 * due to stopping the timer while it was converting.
@@ -405,17 +379,17 @@ void gadcLowSpeedGet(uint32_t physdev, adcsample_t *buffer) {
 
 	/* Start the Low Speed Timer */
 	gfxSemInit(&mysem, 1, 1);
-	gfxMutexEnter(&gadcmutex);
+	gfxMutexEnter(&LowSpeedMutex);
 	if (!gtimerIsActive(&LowSpeedGTimer))
 		gtimerStart(&LowSpeedGTimer, LowSpeedGTimerCallback, 0, TRUE, TIME_INFINITE);
-	gfxMutexExit(&gadcmutex);
+	gfxMutexExit(&LowSpeedMutex);
 
 	while(1) {
 		/* Wait for an available slot */
-		gfxSemWait(&gadcsem, TIME_INFINITE);
+		gfxSemWait(&LowSpeedSlotSem, TIME_INFINITE);
 
 		/* Find a slot */
-		gfxMutexEnter(&gadcmutex);
+		gfxMutexEnter(&LowSpeedMutex);
 		for(p = ls; p < &ls[GADC_MAX_LOWSPEED_DEVICES]; p++) {
 			if (!(p->flags & GADC_FLG_ISACTIVE)) {
 				p->lld.physdev = physdev;
@@ -423,13 +397,13 @@ void gadcLowSpeedGet(uint32_t physdev, adcsample_t *buffer) {
 				p->fn = BSemSignalCallback;
 				p->param = &mysem;
 				p->flags = GADC_FLG_ISACTIVE;
-				gfxMutexExit(&gadcmutex);
+				gfxMutexExit(&LowSpeedMutex);
 				StartADC(FALSE);
 				gfxSemWait(&mysem, TIME_INFINITE);
 				return;
 			}
 		}
-		gfxMutexExit(&gadcmutex);
+		gfxMutexExit(&LowSpeedMutex);
 
 		/**
 		 *  We should never get here - the count semaphore must be wrong.
@@ -442,7 +416,7 @@ bool_t gadcLowSpeedStart(uint32_t physdev, adcsample_t *buffer, GADCCallbackFunc
 	struct lsdev *p;
 
 	/* Start the Low Speed Timer */
-	gfxMutexEnter(&gadcmutex);
+	gfxMutexEnter(&LowSpeedMutex);
 	if (!gtimerIsActive(&LowSpeedGTimer))
 		gtimerStart(&LowSpeedGTimer, LowSpeedGTimerCallback, 0, TRUE, TIME_INFINITE);
 
@@ -450,18 +424,18 @@ bool_t gadcLowSpeedStart(uint32_t physdev, adcsample_t *buffer, GADCCallbackFunc
 	for(p = ls; p < &ls[GADC_MAX_LOWSPEED_DEVICES]; p++) {
 		if (!(p->flags & GADC_FLG_ISACTIVE)) {
 			/* We know we have a slot - this should never wait anyway */
-			gfxSemWait(&gadcsem, TIME_IMMEDIATE);
+			gfxSemWait(&LowSpeedSlotSem, TIME_IMMEDIATE);
 			p->lld.physdev = physdev;
 			p->lld.buffer = buffer;
 			p->fn = fn;
 			p->param = param;
 			p->flags = GADC_FLG_ISACTIVE;
-			gfxMutexExit(&gadcmutex);
+			gfxMutexExit(&LowSpeedMutex);
 			StartADC(FALSE);
 			return TRUE;
 		}
 	}
-	gfxMutexExit(&gadcmutex);
+	gfxMutexExit(&LowSpeedMutex);
 	return FALSE;
 }
 
diff --git a/src/gadc/sys_defs.h b/src/gadc/sys_defs.h
index f6349dfe..21e81fb6 100644
--- a/src/gadc/sys_defs.h
+++ b/src/gadc/sys_defs.h
@@ -73,15 +73,10 @@ typedef struct GEventADC_t {
 		 * @{
 		 */
 		#define	GADC_HSADC_LOSTEVENT		0x0001		/**< @brief The last GEVENT_HSDADC event was lost */
+		#define	GADC_HSADC_RUNNING			0x0002		/**< @brief The High Speed ADC is currently running */
+		#define	GADC_HSADC_GOTBUFFER		0x0004		/**< @brief A buffer is ready for processing */
+		#define	GADC_HSADC_STALL			0x0008		/**< @brief The High Speed ADC has stalled due to no free buffers */
 		/** @} */
-	/**
-	 * @brief The number of conversions in the buffer
-	 */
-	size_t			count;
-	/**
-	 * @brief The buffer containing the conversion samples
-	 */
-	adcsample_t		*buffer;
 } GEventADC;
 /** @} */
 
@@ -93,7 +88,7 @@ typedef void (*GADCCallbackFunction)(adcsample_t *buffer, void *param);
 /**
  * @brief A callback function (executed in an ISR context) for a high speed conversion
  */
-typedef void (*GADCISRCallbackFunction)(adcsample_t *buffer, size_t size);
+typedef void (*GADCISRCallbackFunction)(void);
 
 /*===========================================================================*/
 /* External declarations.                                                    */
@@ -109,40 +104,28 @@ extern "C" {
  *
  * @param[in] physdev			A value passed to describe which physical ADC devices/channels to use.
  * @param[in] frequency			The frequency to create ADC conversions
- * @param[in] buffer			The static buffer to put the ADC samples into.
- * @param[in] bufcount			The total number of conversions that will fit in the buffer.
- * @param[in] samplesPerEvent	The number of conversions to do before returning an event.
  *
  * @note				If the high speed ADC is running it will be stopped. The Event subsystem is
  * 						disconnected from the high speed ADC and any binary semaphore event is forgotten.
- * @note				bufcount must be greater than countPerEvent (usually 2 or more times) otherwise
- * 						the buffer will be overwritten with new data while the application is still trying
- * 						to process the old data.
- * @note				Due to a bug/feature in Chibi-OS countPerEvent must be even. If bufcount is not
- * 						evenly divisable by countPerEvent, the remainder must also be even.
+ * @note				ChibiOS ONLY: Due to a bug in ChibiOS each buffer on the free-list must contain an even number of
+ * 						samples and for multi-channel devices it must hold a number of samples that is evenly divisible
+ * 						by 2 times the number of active channels.
  * @note				The physdev parameter may be used to turn on more than one ADC channel.
- * 						Each channel is then interleaved into the provided buffer. Note 'bufcount'
- * 						and 'countPerEvent' parameters describe the number of conversions not the
- * 						number of samples.
+ * 						Each channel is then interleaved into the provided buffer. Make sure your buffers all hold
+ * 						a number of samples evenly divisible by the number of active channels.
  * 						As an example, if physdev turns on 2 devices then the buffer contains
- * 						alternate device samples and the buffer must contain 2 * bufcount samples.
+ * 						alternate device samples and the buffer must contain multiples of 2 samples.
  * 						The exact meaning of physdev is hardware dependent.
- * @note				The buffer is circular. When the end of the buffer is reached it will start
- * 						putting data into the beginning of the buffer again.
- * @note				The event listener must process the event (and the data in it) before the
- * 						next event occurs. If not, the following event will be lost.
- * @note				If bufcount is evenly divisable by countPerEvent, then every event will return
- * 						countPerEvent conversions. If bufcount is not evenly divisable, it will return
- * 						a block of samples containing less than countPerEvent samples when it reaches the
- * 						end of the buffer.
  * @note				While the high speed ADC is running, low speed conversions can only occur at
  * 						the frequency of the high speed events. Thus if high speed events are
- * 						being created at 50Hz (eg countPerEvent = 100, frequency = 5kHz) then the maximum
+ * 						being created at 50Hz (eg 100 samples/buffer, frequency = 5kHz) then the maximum
  * 						frequency for low speed conversions will be 50Hz.
+ * @note				Only a single sample format is supported - that provided by the GADC driver. That sample
+ * 						format applies to both high speed and low speed sampling.
  *
  * @api
  */
-void gadcHighSpeedInit(uint32_t physdev, uint32_t frequency, adcsample_t *buffer, size_t bufcount, size_t samplesPerEvent);
+void gadcHighSpeedInit(uint32_t physdev, uint32_t frequency);
 
 #if GFX_USE_GEVENT || defined(__DOXYGEN__)
 	/**
@@ -170,7 +153,7 @@ void gadcHighSpeedInit(uint32_t physdev, uint32_t frequency, adcsample_t *buffer
  *
  * @note				Passing a NULL for isrfn will turn off signalling via this method as will calling
  * 						@p gadcHighSpeedInit().
- * @note				The high speed ADC is capable of signalling via this method, a binary semaphore and the GEVENT
+ * @note				The high speed ADC is capable of signalling via this method, a blocked thread and the GEVENT
  * 						sub-system at the same time.
  *
  * @api
@@ -178,19 +161,24 @@ void gadcHighSpeedInit(uint32_t physdev, uint32_t frequency, adcsample_t *buffer
 void gadcHighSpeedSetISRCallback(GADCISRCallbackFunction isrfn);
 
 /**
- * @brief				Allow retrieving of results from the high speed ADC using a Binary Semaphore and a static event buffer.
+ * @brief		Get a filled buffer from the ADC
+ * @return		A GDataBuffer pointer or NULL if the timeout is exceeded
  *
- * @param[in] pbsem			The semaphore is signaled when data is available.
- * @param[in] pEvent		The static event buffer to place the result information.
- *
- * @note				Passing a NULL for pbsem or pEvent will turn off signalling via this method as will calling
- * 						@p gadcHighSpeedInit().
- * @note				The high speed ADC is capable of signalling via this method, an ISR callback and the GEVENT
- * 						sub-system at the same time.
+ * @params[in] ms	The maximum amount of time in milliseconds to wait for data if some is not currently available.
  *
+ * @note		After processing the data, your application must return the buffer to the free-list so that
+ * 				it can be used again. This can be done using @p gfxBufferRelease().
+ * @note		A buffer may be returned to the free-list before you have finished processing it provided you finish
+ * 				processing it before GADC re-uses it. This is useful when RAM usage is critical to reduce the number
+ * 				of buffers required. It works before the free list is a FIFO queue and therefore buffers are kept
+ * 				in the queue as long as possible before they are re-used.
+ * @note		The function ending with "I" is the interrupt class function.
  * @api
+ * @{
  */
-void gadcHighSpeedSetBSem(gfxSem *pbsem, GEventADC *pEvent);
+GDataBuffer *gadcHighSpeedGetData(delaytime_t ms);
+GDataBuffer *gadcHighSpeedGetDataI(void);
+/* @} */
 
 /**
  * @brief   Start the high speed ADC conversions.
diff --git a/src/gadc/sys_rules.h b/src/gadc/sys_rules.h
index 7272337e..363b2434 100644
--- a/src/gadc/sys_rules.h
+++ b/src/gadc/sys_rules.h
@@ -24,6 +24,17 @@
 		#undef GFX_USE_GTIMER
 		#define	GFX_USE_GTIMER		TRUE
 	#endif
+	#if !GFX_USE_GQUEUE || !GQUEUE_NEED_GSYNC || !GQUEUE_NEED_BUFFERS
+		#if GFX_DISPLAY_RULE_WARNINGS
+			#warning "GADC: GFX_USE_GQUEUE, GQUEUE_NEED_BUFFERS and GQUEUE_NEED_GSYNC are required if GFX_USE_GADC is TRUE. They have been turned on for you."
+		#endif
+		#undef GFX_USE_GQUEUE
+		#define	GFX_USE_GQUEUE		TRUE
+		#undef GQUEUE_NEED_BUFFERS
+		#define	GQUEUE_NEED_BUFFERS		TRUE
+		#undef GQUEUE_NEED_GSYNC
+		#define	GQUEUE_NEED_GSYNC		TRUE
+	#endif
 #endif
 
 #endif /* _GADC_RULES_H */