Merge branch 'master' of https://bitbucket.org/Tectu/ugfx into gwin

4 files changed, 332 insertions, 484 deletions

diff --git a/src/gadc/driver.h b/src/gadc/driver.h
index 4427f4f0..e85eed48 100644
--- a/src/gadc/driver.h
+++ b/src/gadc/driver.h
@@ -27,30 +27,35 @@
 
 /**
  * @brief				The structure passed to start a timer conversion
- * @note				We use the structure instead of parameters purely to save
- * 						interrupt stack space which is very limited in some platforms.
  * @{
  */
-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. */
-	bool_t			now;			/* @< Trigger the first conversion now rather than waiting for the first timer interrupt (if possible) */
-	} GadcLldTimerData;
+typedef struct GadcTimerJob_t {
+	uint32_t		physdev;					// @< The physical device/s. The exact meaning of physdev is hardware dependent.
+	uint32_t		frequency;					// @< The frequency to sample
+	adcsample_t		*buffer;					// @< Where to put the samples
+	size_t			todo;						// @< How many conversions to do
+	size_t			done;						// @< How many conversions have already been done
+} GadcTimerJob;
 /* @} */
 
 /**
- * @brief				The structure passed to start a non-timer conversion
- * @note				We use the structure instead of parameters purely to save
- * 						interrupt stack space which is very limited in some platforms.
+ * @brief				The structure passed to do a single conversion
  * @{
  */
-typedef struct GadcLldNonTimerData_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. */
-	} GadcLldNonTimerData;
+typedef struct GadcNonTimerJob_t {
+	uint32_t				physdev;			// @< The physical device/s. The exact meaning of physdev is hardware dependent.
+	adcsample_t				*buffer;			// @< Where to put the samples.
+	} GadcNonTimerJob;
 /* @} */
 
+/*===========================================================================*/
+/* External declarations.                                                    */
+/*===========================================================================*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /**
  * @brief				These routines are the callbacks that the driver uses.
  * @details				Defined in the high level GADC code.
@@ -58,40 +63,21 @@ typedef struct GadcLldNonTimerData_t {
  * @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	Indicate that some data has been placed into the buffer for the current job
+	 *
+	 * @param[in] n		The number of samples placed in the buffer
+	 *
+	 * @note		Calling this with n = 0 causes the current job to be terminated early or aborted.
+	 * 				It can be called in this mode on an ADC conversion error. Any job will then be
+	 * 				restarted by the high level code as appropriate.
+	 */
+	void gadcGotDataI(size_t n);
 /**
  * @}
  */
 
 /**
- * @brief				This can be incremented by the low level driver if a timer interrupt is missed.
- * @details				Defined in the high level GADC code.
- *
- * @notapi
- */
-extern volatile bool_t GADC_Timer_Missed;
-
-/*===========================================================================*/
-/* External declarations.                                                    */
-/*===========================================================================*/
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/**
  * @brief				Initialise the driver
  *
  * @api
@@ -99,86 +85,63 @@ extern "C" {
 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.
+ * @brief				Using the hardware dependant "physdev", return the number of samples for each conversion
  *
- * @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	The hardware dependent physical device descriptor
  *
- * @param[in] physdev	A value passed to describe which physical ADC devices/channels to use.
+ * @return				The number of samples per conversion
  *
- * @return				Number of samples of the convesion
  * @api
  */
-size_t gadc_lld_samples_per_conversion(uint32_t physdev);
+size_t gadc_lld_samplesperconversion(uint32_t physdev);
 
 /**
  * @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] freq		The frequency for the timer
  *
- * @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
- * 						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
- * 						the GADC_Timer_Missed variable.
+ * @note				This will only be called if the timer is currently stopped.
  *
  * @api
+ * @iclass
  */
-void gadc_lld_start_timer(uint32_t physdev, uint32_t frequency);
+void gadc_lld_start_timerI(uint32_t freq);
 
 /**
  * @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.
+ * @note				This will only be called if the timer is currently running and all timer jobs
+ * 						have been completed/aborted.
  *
  * @api
+ * @iclass
  */
-void gadc_lld_stop_timer(uint32_t physdev);
+void gadc_lld_stop_timerI(void);
 
 /**
- * @brief				Start a "timer" conversion.
- * @details				Starts a series of conversions triggered by the timer.
+ * @brief				Start a set of high frequency conversions.
  *
- * @param[in] pgtd		Contains the parameters for the timer conversion.
+ * @note				This will only be called if the timer is currently running and the ADC should be ready for
+ * 						a new job.
  *
- * @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 high level code ensures that this is not called while a non-timer conversion is in
- * 						progress
+ * @param[in] pjob		The job to be started.
  *
+ * @api
  * @iclass
  */
-void gadc_lld_adc_timerI(GadcLldTimerData *pgtd);
+void gadc_lld_timerjobI(GadcTimerJob *pjob);
 
 /**
- * @brief				Start a "non-timer" conversion.
- * @details				Starts a single conversion now.
+ * @brief				Start a non-timer conversion.
  *
- * @param[in] pgntd		Contains the parameters for the non-timer conversion.
+ * @note				This will only be called if the ADC should be ready for a new job.
  *
- * @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 high level code ensures that this is not called while a timer conversion is in
- * 						progress
+ * @param[in] pjob		The job to be started
  *
+ * @api
  * @iclass
  */
-void gadc_lld_adc_nontimerI(GadcLldNonTimerData *pgntd);
+void gadc_lld_nontimerjobI(GadcNonTimerJob *pjob);
 
 #ifdef __cplusplus
 }
diff --git a/src/gadc/gadc.c b/src/gadc/gadc.c
index 8ae431b0..d307519b 100644
--- a/src/gadc/gadc.c
+++ b/src/gadc/gadc.c
@@ -23,228 +23,151 @@
 	#error "GADC: GADC_MAX_HIGH_SPEED_SAMPLERATE has been set too high. It must be less than half the maximum CPU rate"
 #endif
 
-#define GADC_MAX_LOWSPEED_DEVICES	((GADC_MAX_SAMPLE_FREQUENCY/GADC_MAX_HIGH_SPEED_SAMPLERATE)-1)
-#if GADC_MAX_LOWSPEED_DEVICES > 4
-	#undef GADC_MAX_LOWSPEED_DEVICES
-	#define GADC_MAX_LOWSPEED_DEVICES	4
-#endif
-
-volatile bool_t GADC_Timer_Missed;
-
-static gfxSem	gadcsem;
-static gfxMutex	gadcmutex;
-static GTimer	LowSpeedGTimer;
+#define GADC_HSADC_GTIMER		0x8000
+#define GADC_ADC_RUNNING		0x4000
+#define GADC_HSADC_CONVERTION	0x2000
+
+typedef struct NonTimerData_t {
+	gfxQueueGSyncItem		next;
+	GADCCallbackFunction	callback;
+	union {
+		void				*param;
+		gfxSem				sigdone;
+	};
+	GadcNonTimerJob			job;
+	} NonTimerData;
+
+static volatile uint16_t		hsFlags;
+static size_t					hsBytesPerConv;
+static GadcTimerJob				hsJob;
+static GDataBuffer				*hsData;
+static gfxQueueGSync			hsListDone;
+static GADCISRCallbackFunction	hsISRcallback;
 #if GFX_USE_GEVENT
-	static GTimer	HighSpeedGTimer;
+	static GTimer				hsGTimer;
 #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
-
-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;
-	GADCISRCallbackFunction	isrfn;
-	} hs;
-
-static struct lsdev {
-	// Our status flags
-	uint16_t				flags;
-
-	// What we started with
-	GadcLldNonTimerData		lld;
-	GADCCallbackFunction	fn;
-	void					*param;
-	} ls[GADC_MAX_LOWSPEED_DEVICES];
-
-static struct lsdev *curlsdev;
-
-/* Find the next conversion to activate */
-static inline void FindNextConversionI(void) {
-	if (curlsdev) {
-		/**
-		 * Now we have done a low speed conversion - start looking for the next conversion
-		 * We only look forward to ensure we get a high speed conversion at least once
-		 * every GADC_MAX_LOWSPEED_DEVICES conversions.
-		 */
-		curlsdev++;
+static GTimer					lsGTimer;
+static gfxQueueGSync			lsListToDo;
+static gfxQueueGSync			lsListDone;
+static NonTimerData				*lsData;
 
-	} else {
+void gadcGotDataI(size_t n) {
+	if ((hsFlags & GADC_HSADC_CONVERTION)) {
 
-		/* Now we have done a high speed conversion - start looking for low speed conversions */
-		curlsdev = ls;
-	}
+		// A set of timer conversions is done - add them
+		hsJob.done += n;
 
-	/**
-	 * Look for the next thing to do.
-	 */
-	while(curlsdev < &ls[GADC_MAX_LOWSPEED_DEVICES]) {
-		if ((curlsdev->flags & (GADC_FLG_ISACTIVE|GADC_FLG_ISDONE)) == GADC_FLG_ISACTIVE) {
-			gadc_lld_adc_nontimerI(&curlsdev->lld);
+		// Are we finished yet? (or driver signalled complete now)
+		if (n && hsJob.done < hsJob.todo)
 			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;
-	}
 
-	/* Nothing more to do */
-	gflags &= ~GADC_GFLG_ISACTIVE;
-}
-
-void GADC_ISR_CompleteI(ADCDriver *adcp, adcsample_t *buffer, size_t n) {
-	(void) adcp;
+		// Clear event flags we might set
+		hsFlags &= ~(GADC_HSADC_GOTBUFFER|GADC_HSADC_STALL);
 
-	if (curlsdev) {
-		/* This interrupt must be in relation to the low speed device */
+		// Is there any data in it
+		if (!hsJob.done) {
 
-		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);
+			// Oops - no data in this buffer. Just return it to the free-list
+			gfxBufferReleaseI(hsData);
+			goto starttimerjob;					// Restart the timer job
 		}
 
-		#if 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;
-			return;
-
+		// Save the buffer on the hsListDone list
+		hsData->len = hsJob.done * hsBytesPerConv;
+		gfxQueueGSyncPutI(&hsListDone, (gfxQueueGSyncItem *)hsData);
+		hsFlags |= GADC_HSADC_GOTBUFFER;
+
+		/* Signal a buffer completion */
+		if (hsISRcallback)
+			hsISRcallback();
+		#if GFX_USE_GEVENT
+			if (hsFlags & GADC_HSADC_GTIMER)
+				gtimerJabI(&hsGTimer);
 		#endif
 
-	} else {
-		/* 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;
-
-			/* Signal the user with the data */
-			if (hs.pEvent) {
-				#if GFX_USE_GEVENT
-					hs.pEvent->type = GEVENT_ADC;
-				#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);
+		// Stop if we have been told to
+		if (!(hsFlags & GADC_HSADC_RUNNING)) {
+			gadc_lld_stop_timerI();
 
-			#if GFX_USE_GEVENT
-				if (hs.flags & GADC_FLG_GTIMER)
-					gtimerJabI(&HighSpeedGTimer);
-			#endif
+		// Get the next free buffer
+		} else if (!(hsData = gfxBufferGetI())) {
 
-			/* Adjust what we have left to do */
-			hs.lld.count -= n;
-			hs.remaining -= n;
+			// Oops - no free buffers. Stall
+			hsFlags &= ~GADC_HSADC_RUNNING;
+			hsFlags |= GADC_HSADC_STALL;
+			gadc_lld_stop_timerI();
 
-			/* Half completion - We have done all we can for now - wait for the next interrupt */
-			if (hs.lld.count)
-				return;
+		// Prepare the next job
+		} else {
 
-			/* 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;
-			}
-			hs.lld.count = hs.remaining < hs.samplesPerEvent ? hs.remaining : hs.samplesPerEvent;
+			// Return this new job
+			#if GFX_USE_OS_CHIBIOS
+				// ChibiOS api bug - samples must be even
+				hsJob.todo = (hsData->size / hsBytesPerConv) & ~1;
+			#else
+				hsJob.todo = hsData->size / hsBytesPerConv;
+			#endif
+			hsJob.done = 0;
+			hsJob.buffer = (adcsample_t *)(hsData+1);
 		}
-	}
 
-	/**
-	 * Look for the next thing to do.
-	 */
-	FindNextConversionI();
-}
+		// Start a job preferring a non-timer job
+		if ((lsData = (NonTimerData *)gfxQueueGSyncGetI(&lsListToDo))) {
+			hsFlags &= ~GADC_HSADC_CONVERTION;
+			gadc_lld_nontimerjobI(&lsData->job);
+		} else if ((hsFlags & GADC_HSADC_RUNNING)) {
+			hsFlags |= GADC_HSADC_CONVERTION;
+			gadc_lld_timerjobI(&hsJob);
+		} else
+			hsFlags &= ~GADC_ADC_RUNNING;
 
-void GADC_ISR_ErrorI(ADCDriver *adcp, adcerror_t err) {
-	(void) adcp;
-	(void) err;
-
-	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
-			/**
-			 * 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;
-			gtimerJabI(&LowSpeedGTimer);
-			return;
+	} else {
 
-		#endif
+		// Did it fail
+		if (!n) {
+			// Push it back on the head of the queue - it didn't actually get done
+			gfxQueueGSyncPushI(&lsListToDo, (gfxQueueGSyncItem *)lsData);
+			lsData = 0;
+			goto starttimerjob;
+		}
 
-	} else {
-		if (hs.flags & GADC_FLG_ISACTIVE)
-			/* Mark the error and then try to repeat it */
-			hs.flags |= GADC_FLG_ERROR;
+		// A non-timer job completed - signal
+		if (lsData->callback) {
+			// Put it on the completed list and signal the timer to do the call-backs
+			gfxQueueGSyncPutI(&lsListDone, (gfxQueueGSyncItem *)lsData);
+			gtimerJabI(&lsGTimer);
+		} else {
+			// Signal the thread directly
+			gfxSemSignalI(&lsData->sigdone);
+		}
+		lsData = 0;
+
+		// Start a job preferring a timer job
+starttimerjob:
+		if ((hsFlags & GADC_HSADC_RUNNING)) {
+			hsFlags |= GADC_HSADC_CONVERTION;
+			gadc_lld_timerjobI(&hsJob);
+		} else if ((lsData = (NonTimerData *)gfxQueueGSyncGetI(&lsListToDo))) {
+			hsFlags &= ~GADC_HSADC_CONVERTION;
+			gadc_lld_nontimerjobI(&lsData->job);
+		} else
+			hsFlags &= ~GADC_ADC_RUNNING;
 	}
-
-	/* Start the next conversion */
-	FindNextConversionI();
 }
 
 /* Our module initialiser */
 void _gadcInit(void)
 {
 	gadc_lld_init();
-	gfxSemInit(&gadcsem, GADC_MAX_LOWSPEED_DEVICES, GADC_MAX_LOWSPEED_DEVICES);
-	gfxMutexInit(&gadcmutex);
-	gtimerInit(&LowSpeedGTimer);
+
+	gfxQueueGSyncInit(&hsListDone);
 	#if GFX_USE_GEVENT
-		gtimerInit(&HighSpeedGTimer);
+		gtimerInit(&hsGTimer);
 	#endif
+	gtimerInit(&lsGTimer);
+	gfxQueueGSyncInit(&lsListToDo);
+	gfxQueueGSyncInit(&lsListDone);
 }
 
 void _gadcDeinit(void)
@@ -252,26 +175,13 @@ void _gadcDeinit(void)
 	/* commented stuff is ToDo */
 
 	// gadc_lld_deinit();
-	gfxSemDestroy(&gadcsem);
-	gfxMutexDestroy(&gadcmutex);
-	gtimerDeinit(&LowSpeedGTimer);
+	gfxQueueGSyncDeinit(&hsListDone);
 	#if GFX_USE_GEVENT
-		gtimerDeinit(&HighSpeedGTimer);
+		gtimerDeinit(&hsGTimer);
 	#endif	
-}
-
-static inline void StartADC(bool_t onNoHS) {
-	gfxSystemLock();
-	if (!(gflags & GADC_GFLG_ISACTIVE) || (onNoHS && !curlsdev))
-		FindNextConversionI();
-	gfxSystemUnlock();
-}
-
-static void BSemSignalCallback(adcsample_t *buffer, void *param) {
-	(void) buffer;
-
-	/* Signal the BinarySemaphore parameter */
-	gfxSemSignal((gfxSem *)param);
+	gtimerDeinit(&lsGTimer);
+	gfxQueueGSyncDeinit(&lsListToDo);
+	gfxQueueGSyncDeinit(&lsListDone);
 }
 
 #if GFX_USE_GEVENT
@@ -281,7 +191,7 @@ static void BSemSignalCallback(adcsample_t *buffer, void *param) {
 		GEventADC		*pe;
 
 		psl = 0;
-		while ((psl = geventGetSourceListener((GSourceHandle)(&HighSpeedGTimer), psl))) {
+		while ((psl = geventGetSourceListener((GSourceHandle)(&hsGTimer), psl))) {
 			if (!(pe = (GEventADC *)geventGetEventBuffer(psl))) {
 				// This listener is missing - save this.
 				psl->srcflags |= GADC_HSADC_LOSTEVENT;
@@ -289,180 +199,162 @@ 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 = (hsFlags & (GADC_HSADC_RUNNING|GADC_HSADC_GOTBUFFER|GADC_HSADC_STALL)) | psl->srcflags;
 			psl->srcflags = 0;
 			geventSendEvent(psl);
 		}
 	}
 #endif
 
-static void LowSpeedGTimerCallback(void *param) {
-	(void) param;
-	GADCCallbackFunction	fn;
-	void					*prm;
-	adcsample_t				*buffer;
-	struct lsdev			*p;
-
-	#if ADC_ISR_FULL_CODE_BUG
-		/* Ensure the ADC is running if it needs to be - Bugfix HACK */
-		StartADC(FALSE);
-	#endif
-
-	/**
-	 * Look for completed low speed timers.
-	 * We don't need to take the mutex as we are the only place that things are freed and we
-	 * do that atomically.
-	 */
-	for(p=ls; p < &ls[GADC_MAX_LOWSPEED_DEVICES]; p++) {
-		if ((p->flags & (GADC_FLG_ISACTIVE|GADC_FLG_ISDONE)) == (GADC_FLG_ISACTIVE|GADC_FLG_ISDONE)) {
-			/* This item is done - perform its callback */
-			fn = p->fn;				// Save the callback details
-			prm = p->param;
-			buffer = p->lld.buffer;
-			p->fn = 0;				// Needed to prevent the compiler removing the local variables
-			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
-			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 */
+	if ((hsFlags & GADC_HSADC_RUNNING))
+		gadcHighSpeedStop();
 
 	/* 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.now = FALSE;
-	hs.samplesPerConversion = gadc_lld_samples_per_conversion(physdev);
-	hs.remaining = bufcount;
-	hs.bsem = 0;
-	hs.pEvent = 0;
-	hs.isrfn = 0;
+	hsJob.physdev = physdev;
+	hsJob.frequency = frequency;
+	hsISRcallback = 0;
+	hsBytesPerConv = gadc_lld_samplesperconversion(physdev) * sizeof(adcsample_t);
 }
 
 #if GFX_USE_GEVENT
 	GSourceHandle gadcHighSpeedGetSource(void) {
-		if (!gtimerIsActive(&HighSpeedGTimer))
-			gtimerStart(&HighSpeedGTimer, HighSpeedGTimerCallback, 0, TRUE, TIME_INFINITE);
-		hs.flags |= GADC_FLG_GTIMER;
-		return (GSourceHandle)&HighSpeedGTimer;
+		if (!gtimerIsActive(&hsGTimer))
+			gtimerStart(&hsGTimer, HighSpeedGTimerCallback, 0, TRUE, TIME_INFINITE);
+		hsFlags |= GADC_HSADC_GTIMER;
+		return (GSourceHandle)&hsGTimer;
 	}
 #endif
 
 void gadcHighSpeedSetISRCallback(GADCISRCallbackFunction isrfn) {
-	hs.isrfn = isrfn;
+	hsISRcallback = 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(&hsListDone, ms);
+}
+
+GDataBuffer *gadcHighSpeedGetDataI(void) {
+	return (GDataBuffer *)gfxQueueGSyncGetI(&hsListDone);
 }
 
 void gadcHighSpeedStart(void) {
-	/* If its already going we don't need to do anything */
-	if (hs.flags & GADC_FLG_ISACTIVE)
+	// Safety first
+	if (!hsJob.frequency || !hsBytesPerConv)
 		return;
 
-	gadc_lld_start_timer(hs.lld.physdev, hs.frequency);
-	hs.flags = GADC_FLG_ISACTIVE;
-	StartADC(FALSE);
+	gfxSystemLock();
+	if (!(hsFlags & GADC_HSADC_RUNNING)) {
+		if (!(hsData = gfxBufferGetI())) {
+			// Oops - no free buffers. Stall
+			hsFlags |= GADC_HSADC_STALL;
+			#if GFX_USE_GEVENT
+				if (hsFlags & GADC_HSADC_GTIMER)
+					gtimerJabI(&hsGTimer);
+			#endif
+
+		// Prepare the next job
+		} else {
+
+			#if GFX_USE_OS_CHIBIOS
+				// ChibiOS api bug - samples must be even
+				hsJob.todo = (hsData->size / hsBytesPerConv) & ~1;
+			#else
+				hsJob.todo = hsData->size / hsBytesPerConv;
+			#endif
+			hsJob.done = 0;
+			hsJob.buffer = (adcsample_t *)(hsData+1);
+			hsFlags |= GADC_HSADC_RUNNING;
+
+			// Start the timer
+			gadc_lld_start_timerI(hsJob.frequency);
+
+			// If nothing is running start the job
+			if (!(hsFlags & GADC_ADC_RUNNING)) {
+				hsFlags |= (GADC_HSADC_CONVERTION|GADC_ADC_RUNNING);
+				gadc_lld_timerjobI(&hsJob);
+			}
+		}
+	}
+	gfxSystemUnlock();
 }
 
 void gadcHighSpeedStop(void) {
-	if (hs.flags & GADC_FLG_ISACTIVE) {
-		/* No more from us */
-		hs.flags = 0;
-		gadc_lld_stop_timer(hs.lld.physdev);
-		/*
-		 * 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.
-		 */
-		StartADC(TRUE);
+	// Stop it and wait for completion
+	hsFlags &= ~GADC_HSADC_RUNNING;
+	while ((hsFlags & GADC_HSADC_CONVERTION))
+		gfxYield();
+}
+
+static void LowSpeedGTimerCallback(void *param) {
+	(void) param;
+	NonTimerData		*pdata;
+
+	// Look for completed non-timer jobs and call the call-backs for each
+	while ((pdata = (NonTimerData *)gfxQueueGSyncGet(&lsListDone, TIME_IMMEDIATE))) {
+		pdata->callback(pdata->job.buffer, pdata->param);
+		gfxFree(pdata);
 	}
 }
 
 void gadcLowSpeedGet(uint32_t physdev, adcsample_t *buffer) {
-	struct lsdev	*p;
-	gfxSem			mysem;
+	NonTimerData ndata;
 
-	/* Start the Low Speed Timer */
-	gfxSemInit(&mysem, 1, 1);
-	gfxMutexEnter(&gadcmutex);
-	if (!gtimerIsActive(&LowSpeedGTimer))
-		gtimerStart(&LowSpeedGTimer, LowSpeedGTimerCallback, 0, TRUE, TIME_INFINITE);
-	gfxMutexExit(&gadcmutex);
-
-	while(1) {
-		/* Wait for an available slot */
-		gfxSemWait(&gadcsem, TIME_INFINITE);
-
-		/* Find a slot */
-		gfxMutexEnter(&gadcmutex);
-		for(p = ls; p < &ls[GADC_MAX_LOWSPEED_DEVICES]; p++) {
-			if (!(p->flags & GADC_FLG_ISACTIVE)) {
-				p->lld.physdev = physdev;
-				p->lld.buffer = buffer;
-				p->fn = BSemSignalCallback;
-				p->param = &mysem;
-				p->flags = GADC_FLG_ISACTIVE;
-				gfxMutexExit(&gadcmutex);
-				StartADC(FALSE);
-				gfxSemWait(&mysem, TIME_INFINITE);
-				return;
-			}
-		}
-		gfxMutexExit(&gadcmutex);
+	// Prepare the job
+	gfxSemInit(&ndata.sigdone, 0, 1);
+	ndata.job.physdev = physdev;
+	ndata.job.buffer = buffer;
+	ndata.callback = 0;
 
-		/**
-		 *  We should never get here - the count semaphore must be wrong.
-		 *  Decrement it and try again.
-		 */
+	// Activate it
+	gfxSystemLock();
+	if (!(hsFlags & GADC_ADC_RUNNING)) {
+		// Nothing is running - start the job
+		lsData = &ndata;
+		hsFlags |= GADC_ADC_RUNNING;
+		hsFlags &= ~GADC_HSADC_CONVERTION;
+		gadc_lld_nontimerjobI(&ndata.job);
+	} else {
+		// Just put it on the queue
+		gfxQueueGSyncPutI(&lsListToDo, (gfxQueueGSyncItem *)&ndata);
 	}
+	gfxSystemUnlock();
+
+	// Wait for it to complete
+	gfxSemWait(&ndata.sigdone, TIME_INFINITE);
+	gfxSemDestroy(&ndata.sigdone);
 }
 
 bool_t gadcLowSpeedStart(uint32_t physdev, adcsample_t *buffer, GADCCallbackFunction fn, void *param) {
-	struct lsdev *p;
+	NonTimerData *pdata;
 
 	/* Start the Low Speed Timer */
-	gfxMutexEnter(&gadcmutex);
-	if (!gtimerIsActive(&LowSpeedGTimer))
-		gtimerStart(&LowSpeedGTimer, LowSpeedGTimerCallback, 0, TRUE, TIME_INFINITE);
-
-	/* Find a slot */
-	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);
-			p->lld.physdev = physdev;
-			p->lld.buffer = buffer;
-			p->fn = fn;
-			p->param = param;
-			p->flags = GADC_FLG_ISACTIVE;
-			gfxMutexExit(&gadcmutex);
-			StartADC(FALSE);
-			return TRUE;
-		}
+	if (!gtimerIsActive(&lsGTimer))
+		gtimerStart(&lsGTimer, LowSpeedGTimerCallback, 0, TRUE, TIME_INFINITE);
+
+	// Prepare the job
+	if (!(pdata = gfxAlloc(sizeof(NonTimerData))))
+		return FALSE;
+	pdata->job.physdev = physdev;
+	pdata->job.buffer = buffer;
+	pdata->callback = fn;
+	pdata->param = param;
+
+	// Activate it
+	gfxSystemLock();
+	if (!(hsFlags & GADC_ADC_RUNNING)) {
+		// Nothing is running - start the job
+		lsData = pdata;
+		hsFlags |= GADC_ADC_RUNNING;
+		hsFlags &= ~GADC_HSADC_CONVERTION;
+		gadc_lld_nontimerjobI(&pdata->job);
+	} else {
+		// Just put it on the queue
+		gfxQueueGSyncPutI(&lsListToDo, (gfxQueueGSyncItem *)pdata);
 	}
-	gfxMutexExit(&gadcmutex);
-	return FALSE;
+	gfxSystemUnlock();
+	return TRUE;
 }
 
 #endif /* GFX_USE_GADC */
diff --git a/src/gadc/sys_defs.h b/src/gadc/sys_defs.h
index f6349dfe..b1d1ba1c 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.
- *
- * @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.
- *
+ * @brief		Get a filled buffer from the ADC
+ * @return		A GDataBuffer pointer or NULL if the timeout is exceeded
+ *
+ * @param[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.
@@ -221,12 +209,9 @@ void gadcHighSpeedStop(void);
  * 			completion.
  * @note	The result buffer must be large enough to store one sample per device
  * 			described by the 'physdev' parameter.
- * @note	If calling this routine would exceed @p GADC_MAX_LOWSPEED_DEVICES simultaneous low
- * 			speed devices, the routine will wait for an available slot to complete the
- * 			conversion.
  * @note	Specifying more than one device in physdev is possible but discouraged as the
  * 			calculations to ensure the high speed ADC correctness will be incorrect. Symptoms
- * 			from over-running the high speed ADC include high speed samples being lost.
+ * 			from over-running the high speed ADC include high speed device stalling or samples being lost.
  *
  * @api
  */
@@ -234,7 +219,7 @@ void gadcLowSpeedGet(uint32_t physdev, adcsample_t *buffer);
 
 /**
  * @brief	Perform a low speed ADC conversion with callback (in a thread context)
- * @details	Returns FALSE if there are no free low speed ADC slots. See @p GADC_MAX_LOWSPEED_DEVICES for details.
+ * @details	Returns FALSE if internal memory allocation fails
  *
  * @param[in] physdev		A value passed to describe which physical ADC devices/channels to use.
  * @param[in] buffer		The static buffer to put the ADC samples into.
@@ -249,8 +234,6 @@ void gadcLowSpeedGet(uint32_t physdev, adcsample_t *buffer);
  * 			completion.
  * @note	The result buffer must be large enough to store one sample per device
  * 			described by the 'physdev' parameter.
- * @note	As this routine uses a low speed ADC, it asserts if you try to run more than @p GADC_MAX_LOWSPEED_DEVICES
- * 			at the same time.
  * @note	Specifying more than one device in physdev is possible but discouraged as the
  * 			calculations to ensure the high speed ADC correctness will be incorrect. Symptoms
  * 			from over-running the high speed ADC include high speed samples being lost.
@@ -267,4 +250,3 @@ bool_t gadcLowSpeedStart(uint32_t physdev, adcsample_t *buffer, GADCCallbackFunc
 
 #endif /* _GADC_H */
 /** @} */
-
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 */