SAMA5 ADC/Touchscreen: A little more progress. Still not complete

6 files changed, 368 insertions, 112 deletions

diff --git a/nuttx/arch/arm/src/sama5/chip/sam_adc.h b/nuttx/arch/arm/src/sama5/chip/sam_adc.h
index b722533c4..1755b1f58 100644
--- a/nuttx/arch/arm/src/sama5/chip/sam_adc.h
+++ b/nuttx/arch/arm/src/sama5/chip/sam_adc.h
@@ -289,6 +289,8 @@
 #define ADC_INT_EOC7               (1 << 9)  /* Bit 9:  End of Conversion 9 */
 #define ADC_INT_EOC7               (1 << 10) /* Bit 10: End of Conversion 10 */
 #define ADC_INT_EOC7               (1 << 11) /* Bit 11: End of Conversion 11 */
+#define ADC_INT_EOCALL             (0x00000fff)
+
 #define ADC_INT_XRDY               (1 << 20) /* Bit 20: TS Measure XPOS Ready Interrupt */
 #define ADC_INT_YRDY               (1 << 21) /* Bit 21: TS Measure YPOS Ready Interrupt */
 #define ADC_INT_PRDY               (1 << 22) /* Bit 22: TS Measure Pressure Ready Interrupt */
diff --git a/nuttx/arch/arm/src/sama5/sam_adc.c b/nuttx/arch/arm/src/sama5/sam_adc.c
index 4249a44ab..d8b58010d 100644
--- a/nuttx/arch/arm/src/sama5/sam_adc.c
+++ b/nuttx/arch/arm/src/sama5/sam_adc.c
@@ -1,7 +1,6 @@
 /************************************************************************************
  * arch/arm/src/sama5/sam_adc.c
  *
- *
  *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
@@ -65,6 +64,64 @@
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
+/* Get the set of channel interrupts to enable */
+
+#define SAMA5_CHAN0_ENABLE    0
+#define SAMA5_CHAN1_ENABLE    0
+#define SAMA5_CHAN2_ENABLE    0
+#define SAMA5_CHAN3_ENABLE    0
+#define SAMA5_CHAN4_ENABLE    0
+#define SAMA5_CHAN5_ENABLE    0
+#define SAMA5_CHAN6_ENABLE    0
+#define SAMA5_CHAN7_ENABLE    0
+#define SAMA5_CHAN8_ENABLE    0
+#define SAMA5_CHAN9_ENABLE    0
+#define SAMA5_CHAN10_ENABLE   0
+#define SAMA5_CHAN11_ENABLE   0
+
+#if defined(CONFIG_SAMA5_ADC_CHAN0)
+#  undef SAMA5_CHAN0_ENABLE
+#  define SAMA5_CHAN0_ENABLE  ADC_INT_EOC0
+#elif defined(CONFIG_SAMA5_ADC_CHAN1)
+#  undef SAMA5_CHAN1_ENABLE
+#  define SAMA5_CHAN1_ENABLE  ADC_INT_EOC1
+#elif defined(CONFIG_SAMA5_ADC_CHAN2)
+#  undef SAMA5_CHAN2_ENABLE
+#  define SAMA5_CHAN2_ENABLE  ADC_INT_EOC2
+#elif defined(CONFIG_SAMA5_ADC_CHAN3)
+#  undef SAMA5_CHAN3_ENABLE
+#  define SAMA5_CHAN3_ENABLE  ADC_INT_EOC3
+#elif defined(CONFIG_SAMA5_ADC_CHAN4)
+#  undef SAMA5_CHAN4_ENABLE
+#  define SAMA5_CHAN4_ENABLE  ADC_INT_EOC4
+#elif defined(CONFIG_SAMA5_ADC_CHAN5)
+#  undef SAMA5_CHAN5_ENABLE
+#  define SAMA5_CHAN5_ENABLE  ADC_INT_EOC5
+#elif defined(CONFIG_SAMA5_ADC_CHAN6)
+#  undef SAMA5_CHAN6_ENABLE
+#  define SAMA5_CHAN6_ENABLE  ADC_INT_EOC6
+#elif defined(CONFIG_SAMA5_ADC_CHAN7)
+#  undef SAMA5_CHAN7_ENABLE
+#  define SAMA5_CHAN7_ENABLE  ADC_INT_EOC7
+#elif defined(CONFIG_SAMA5_ADC_CHAN8)
+#  undef SAMA5_CHAN8_ENABLE
+#  define SAMA5_CHAN8_ENABLE  ADC_INT_EOC8
+#elif defined(CONFIG_SAMA5_ADC_CHAN9)
+#  undef SAMA5_CHAN9_ENABLE
+#  define SAMA5_CHAN9_ENABLE  ADC_INT_EOC9
+#elif defined(CONFIG_SAMA5_ADC_CHAN10)
+#  undef SAMA5_CHAN10_ENABLE
+#  define SAMA5_CHAN10_ENABLE  ADC_INT_EOC10
+#elif defined(CONFIG_SAMA5_ADC_CHAN11)
+#  undef SAMA5_CHAN11_ENABLE
+#  define SAMA5_CHAN11_ENABLE  ADC_INT_EOC11
+#endif
+
+#define SAMA5_CHAN_ENABLE \
+  (SAMA5_CHAN0_ENABLE  || SAMA5_CHAN1_ENABLE  || SAMA5_CHAN2_ENABLE  || \
+   SAMA5_CHAN3_ENABLE  || SAMA5_CHAN4_ENABLE  || SAMA5_CHAN5_ENABLE  || \
+   SAMA5_CHAN6_ENABLE  || SAMA5_CHAN7_ENABLE  || SAMA5_CHAN8_ENABLE  || \
+   SAMA5_CHAN9_ENABLE  || SAMA5_CHAN10_ENABLE || SAMA5_CHAN11_ENABLE)
 
 /****************************************************************************
  * Private Types
@@ -74,13 +131,17 @@
 
 struct sam_adc_s
 {
+#ifdef SAMA5_ADC_HAVE_CHANNELS
+  struct adc_dev_s dev; /* The external via of the ADC device */
+#endif
+
   /* Debug stuff */
 
 #ifdef CONFIG_SAMA5_ADC_REGDEBUG
-   bool               wrlast;     /* Last was a write */
-   uintptr_t          addrlast;   /* Last address */
-   uint32_t           vallast;    /* Last value */
-   int                ntimes;     /* Number of times */
+   bool wrlast;         /* Last was a write */
+   uintptr_t addrlast;  /* Last address */
+   uint32_t vallast;    /* Last value */
+   int ntimes;          /* Number of times */
 #endif
 };
 
@@ -90,31 +151,32 @@ struct sam_adc_s
 /* Register operations ******************************************************/
 
 #if defined(CONFIG_SAMA5_ADC_REGDEBUG) && defined(CONFIG_DEBUG)
-static bool sam_adc_checkreg(struct sam_gmac_s *priv, bool wr,
-                         uint32_t regval, uintptr_t address);
-static uint32_t sam_adc_getreg(struct sam_gmac_s *priv, uintptr_t addr);
-static void sam_adc_putreg(struct sam_gmac_s *priv, uintptr_t addr, uint32_t val);
-#else
-# define sam_adc_getreg(priv,addr)      getreg32(addr)
-# define sam_adc_putreg(priv,addr,val)  putreg32(val,addr)
+static bool sam_adc_checkreg(struct sam_adc_s *priv, bool wr,
+                             uint32_t regval, uintptr_t address);
 #endif
 
 /* ADC interrupt handling */
 
+#ifdef SAMA5_ADC_HAVE_CHANNELS
+static void sam_adc_endconversion(struct sam_adc_s *priv, uint32_t pending);
+#endif
 static int  sam_adc_interrupt(int irq, void *context);
 
 /* ADC methods */
 
-static void sam_adc_reset(FAR struct adc_dev_s *dev);
-static int  sam_adc_setup(FAR struct adc_dev_s *dev);
-static void sam_adc_shutdown(FAR struct adc_dev_s *dev);
-static void sam_adc_rxint(FAR struct adc_dev_s *dev, bool enable);
-static int  sam_adc_ioctl(FAR struct adc_dev_s *dev, int cmd, unsigned long arg);
+#ifdef SAMA5_ADC_HAVE_CHANNELS
+static void sam_adc_reset(struct adc_dev_s *dev);
+static int  sam_adc_setup(struct adc_dev_s *dev);
+static void sam_adc_shutdown(struct adc_dev_s *dev);
+static void sam_adc_rxint(struct adc_dev_s *dev, bool enable);
+static int  sam_adc_ioctl(struct adc_dev_s *dev, int cmd, unsigned long arg);
+#endif
 
 /****************************************************************************
  * Private Data
  ****************************************************************************/
 
+#ifdef SAMA5_ADC_HAVE_CHANNELS
 /* ADC lower half device operations */
 
 static const struct adc_ops_s g_adcops =
@@ -125,20 +187,21 @@ static const struct adc_ops_s g_adcops =
   .ao_rxint    = sam_adc_rxint,
   .ao_ioctl    = sam_adc_ioctl,
 };
+#endif
 
 /* ADC internal state */
 
-static struct sam_adc_s g_adcpriv =
-{
-};
+static struct sam_adc_s g_adcpriv;
 
+#ifdef SAMA5_ADC_HAVE_CHANNELS
 /* ADC device instance */
 
 static struct adc_dev_s g_adcdev =
 {
   .ad_ops      = &g_adcops,
-  .ad_priv     = &g_adcpriv,
+  .ad_priv     = &g_adcpriv.dev,
 };
+#endif
 
 /****************************************************************************
  * Private Functions
@@ -161,7 +224,7 @@ static struct adc_dev_s g_adcdev =
  ****************************************************************************/
 
 #ifdef CONFIG_SAMA5_ADC_REGDEBUG
-static bool sam_adc_checkreg(struct sam_gmac_s *priv, bool wr,
+static bool sam_adc_checkreg(struct sam_adc_s *priv, bool wr,
                              uint32_t regval, uintptr_t address)
 {
   if (wr      == priv->wrlast &&   /* Same kind of access? */
@@ -198,48 +261,7 @@ static bool sam_adc_checkreg(struct sam_gmac_s *priv, bool wr,
 }
 #endif
 
-/****************************************************************************
- * Name: sam_adc_getreg
- *
- * Description:
- *  Read any 32-bit register using an absolute address.
- *
- ****************************************************************************/
-
-#ifdef CONFIG_SAMA5_ADC_REGDEBUG
-static uint32_t sam_adc_getreg(struct sam_gmac_s *priv, uintptr_t address)
-{
-  uint32_t regval = getreg32(address);
-
-  if (sam_adc_checkreg(priv, false, regval, address))
-    {
-      lldbg("%08x->%08x\n", address, regval);
-    }
-
-  return regval;
-}
-#endif
-
-/****************************************************************************
- * Name: sam_adc_putreg
- *
- * Description:
- *  Write to any 32-bit register using an absolute address.
- *
- ****************************************************************************/
-
-#ifdef CONFIG_SAMA5_ADC_REGDEBUG
-static void sam_adc_putreg(struct sam_gmac_s *priv, uintptr_t address,
-                       uint32_t regval)
-{
-  if (sam_adc_checkreg(priv, true, regval, address))
-    {
-      lldbg("%08x<-%08x\n", address, regval);
-    }
-
-  putreg32(regval, address);
-}
-#endif
+#ifdef SAMA5_ADC_HAVE_CHANNELS
 
 /****************************************************************************
  * Name: sam_adc_reset
@@ -250,15 +272,20 @@ static void sam_adc_putreg(struct sam_gmac_s *priv, uintptr_t address,
  *
  ****************************************************************************/
 
-static void sam_adc_reset(FAR struct adc_dev_s *dev)
+static void sam_adc_reset(struct adc_dev_s *dev)
 {
-  FAR struct sam_adc_s *priv = (FAR struct sam_adc_s *)dev->ad_priv;
+  struct sam_adc_s *priv = (struct sam_adc_s *)dev->ad_priv;
   irqstate_t flags;
   uint32_t regval;
 
+  /* Reset the ADC controller */
+
   flags = irqsave();
-#warning Missing logic
+  sam_adc_putreg(priv, SAM_ADC_CR, ADC_CR_SWRST);
+
+  /* Reset Mode Register */
 
+  sam_adc_putreg(priv, SAM_ADC_MR, 0);
   irqrestore(flags);
 }
 
@@ -273,9 +300,9 @@ static void sam_adc_reset(FAR struct adc_dev_s *dev)
  *
  ****************************************************************************/
 
-static int sam_adc_setup(FAR struct adc_dev_s *dev)
+static int sam_adc_setup(struct adc_dev_s *dev)
 {
-  FAR struct sam_adc_s *priv = (FAR struct sam_adc_s *)dev->ad_priv;
+  struct sam_adc_s *priv = (struct sam_adc_s *)dev->ad_priv;
   int ret;
 
   /* Attach the ADC interrupt */
@@ -302,15 +329,15 @@ static int sam_adc_setup(FAR struct adc_dev_s *dev)
  *
  ****************************************************************************/
 
-static void sam_adc_shutdown(FAR struct adc_dev_s *dev)
+static void sam_adc_shutdown(struct adc_dev_s *dev)
 {
-  FAR struct sam_adc_s *priv = (FAR struct sam_adc_s *)dev->ad_priv;
+  struct sam_adc_s *priv = (struct sam_adc_s *)dev->ad_priv;
 
   /* Disable ADC interrupts, both at the level of the ADC device and at the
    * level of the NVIC.
    */
-#warning Missing logic
 
+  sam_adc_putreg32(priv, SAM_ADC_IDR, ADC_TSD_INTS);
   up_disable_irq(SAM_IRQ_ADC);
 
   /* Then detach the ADC interrupt handler. */
@@ -326,18 +353,23 @@ static void sam_adc_shutdown(FAR struct adc_dev_s *dev)
  *
  ****************************************************************************/
 
-static void sam_adc_rxint(FAR struct adc_dev_s *dev, bool enable)
+static void sam_adc_rxint(struct adc_dev_s *dev, bool enable)
 {
-  FAR struct sam_adc_s *priv = (FAR struct sam_adc_s *)dev->ad_priv;
+  struct sam_adc_s *priv = (struct sam_adc_s *)dev->ad_priv;
 
   /* Are we enabling or disabling? */
+
   if (enable)
     {
-#warning Missing logic
+      /* Enable channel interrupts */
+
+      sam_adc_putreg32(priv, SAM_ADC_IER, SAMA5_CHAN_ENABLE);
     }
   else
     {
-#warning Missing logic
+      /* Disable channel interrupts */
+
+      sam_adc_putreg32(priv, SAM_ADC_IDR, ADC_INT_EOCALL);
     }
 }
 
@@ -349,7 +381,7 @@ static void sam_adc_rxint(FAR struct adc_dev_s *dev, bool enable)
  *
  ****************************************************************************/
 
-static int sam_adc_ioctl(FAR struct adc_dev_s *dev, int cmd, unsigned long arg)
+static int sam_adc_ioctl(struct adc_dev_s *dev, int cmd, unsigned long arg)
 {
   /* No ioctl commands supported */
 
@@ -357,6 +389,37 @@ static int sam_adc_ioctl(FAR struct adc_dev_s *dev, int cmd, unsigned long arg)
 }
 
 /****************************************************************************
+ * Name: sam_adc_endconversion
+ *
+ * Description:
+ *   End of conversion interrupt handler
+ *
+ ****************************************************************************/
+
+static void sam_adc_endconversion(struct sam_adc_s *priv, uint32_t pending)
+{
+  uint32_t regval;
+  int chan;
+
+  /* Check for the end of conversion event on each channel */
+
+  for (chan = 0; chan < SAM_ADC_NCHANNELS && pending != 0; chan++)
+    {
+      uint32_t bit = ADC_INT_EOC(chan);
+      if ((pending & bit) != 0)
+        {
+          /* Read the ADC sample and pass it to the upper half */
+
+          regval   = sam_adc_getreg(priv, SAM_ADC_CDR(chan));
+          ret      = adc_receive(&priv->dev, chan, regval & ADC_CDR_DATA_MASK);
+          pending &= ~bit;
+        }
+    }
+}
+
+#endif /* SAMA5_ADC_HAVE_CHANNELS */
+
+/****************************************************************************
  * Name: sam_adc_interrupt
  *
  * Description:
@@ -366,11 +429,46 @@ static int sam_adc_ioctl(FAR struct adc_dev_s *dev, int cmd, unsigned long arg)
 
 static int sam_adc_interrupt(int irq, void *context)
 {
-  FAR struct sam_adc_s *priv = (FAR struct sam_adc_s *)g_adcdev.ad_priv;
+  struct sam_adc_s *priv = (struct sam_adc_s *)g_adcdev.ad_priv;
   uint32_t regval;
+  struct sam_adc_s *priv = &g_adcpriv;
+  uint32_t isr;
+  uint32_t imr;
+  uint32_t pending;
+
+  /* Get the set of unmasked, pending ADC interrupts */
+
+  isr = sam_adc_getreg(priv, SAM_ADC_ISR);
+  imr = sam_adc_getreg(priv, SAM_ADC_IMR);
+  pending = isr & imr;
 
-#warning Missing logic
+  /* Handle pending touchscreen interrupts */
+
+#ifdef CONFIG_SAMA5_TOUCHSCREEN
+  if ((pending & ADC_TSD_INTS) != 0)
+    {
+      /* Let the touchscreen handle its interrupts */
+
+      sam_tsd_interrupt(pending);
+      pending &= ~ADC_TSD_INTS;
+    }
+#endif
 
+#ifdef SAMA5_ADC_HAVE_CHANNELS
+  /* Check for end-of-conversion interrupts */
+
+  if ((pending & ADC_INT_EOCALL) != 0)
+    {
+      /* Let the touchscreen handle its interrupts */
+
+      sam_adc_endconversion(pending);
+      pending &= ~ADC_INT_EOCALL;
+    }
+#endif
+
+  /* Make sure that all interrupts were handled */
+
+  DEBUGASSERT(pending == 0);
   return OK;
 }
 
@@ -389,12 +487,54 @@ static int sam_adc_interrupt(int irq, void *context)
  *
  ****************************************************************************/
 
-FAR struct adc_dev_s *sam_adc_initialize(void)
+struct adc_dev_s *sam_adc_initialize(void)
 {
   /* Enable the ADC peripheral clock*/
 
   sam_adc_enableclk();
 
+  /* Configure ADC pins */
+
+#ifdef CONFIG_SAMA5_ADC_CHAN0
+  sam_configpio(PIO_ADC_AD0);
+#endif
+#ifdef CONFIG_SAMA5_ADC_CHAN1
+  sam_configpio(PIO_ADC_AD1);
+#endif
+#ifdef CONFIG_SAMA5_ADC_CHAN2
+  sam_configpio(PIO_ADC_AD2);
+#endif
+#ifdef CONFIG_SAMA5_ADC_CHAN3
+  sam_configpio(PIO_ADC_AD3);
+#endif
+#ifdef CONFIG_SAMA5_ADC_CHAN4
+  sam_configpio(PIO_ADC_AD4);
+#endif
+#ifdef CONFIG_SAMA5_ADC_CHAN5
+  sam_configpio(PIO_ADC_AD5);
+#endif
+#ifdef CONFIG_SAMA5_ADC_CHAN6
+  sam_configpio(PIO_ADC_AD6);
+#endif
+#ifdef CONFIG_SAMA5_ADC_CHAN7
+  sam_configpio(PIO_ADC_AD7);
+#endif
+#ifdef CONFIG_SAMA5_ADC_CHAN8
+  sam_configpio(PIO_ADC_AD8);
+#endif
+#ifdef CONFIG_SAMA5_ADC_CHAN9
+  sam_configpio(PIO_ADC_AD9);
+#endif
+#ifdef CONFIG_SAMA5_ADC_CHAN10
+  sam_configpio(PIO_ADC_AD10);
+#endif
+#ifdef CONFIG_SAMA5_ADC_CHAN11
+  sam_configpio(PIO_ADC_AD11);
+#endif
+#if 0
+  sam_configpio(PIO_ADC_TRG);
+#endif
+
   /* Reset the ADC controller */
 
   sam_adc_putreg(priv, SAM_ADC_CR, ADC_CR_SWRST);
@@ -408,4 +548,49 @@ FAR struct adc_dev_s *sam_adc_initialize(void)
   return &g_adcdev;
 }
 
+/****************************************************************************
+ * Name: sam_adc_getreg
+ *
+ * Description:
+ *  Read any 32-bit register using an absolute address.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_SAMA5_ADC_REGDEBUG
+static uint32_t sam_adc_getreg(ADC_HANDLE handle, uintptr_t address)
+{
+  struct sam_adc_s *priv = (struct sam_adc_s *)handle;
+  uint32_t regval = getreg32(address);
+
+  if (sam_adc_checkreg(priv, false, regval, address))
+    {
+      lldbg("%08x->%08x\n", address, regval);
+    }
+
+  return regval;
+}
+#endif
+
+/****************************************************************************
+ * Name: sam_adc_putreg
+ *
+ * Description:
+ *  Write to any 32-bit register using an absolute address.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_SAMA5_ADC_REGDEBUG
+void sam_adc_putreg(ADC_HANDLE handle, uintptr_t address, uint32_t regval)
+{
+  struct sam_adc_s *priv = (struct sam_adc_s *)handle;
+
+  if (sam_adc_checkreg(priv, true, regval, address))
+    {
+      lldbg("%08x<-%08x\n", address, regval);
+    }
+
+  putreg32(regval, address);
+}
+#endif
+
 #endif /* CONFIG_SAMA5_ADC */
diff --git a/nuttx/arch/arm/src/sama5/sam_adc.h b/nuttx/arch/arm/src/sama5/sam_adc.h
index 8309c624c..803086ec2 100644
--- a/nuttx/arch/arm/src/sama5/sam_adc.h
+++ b/nuttx/arch/arm/src/sama5/sam_adc.h
@@ -50,6 +50,40 @@
  ****************************************************************************/
 /* Configuration ************************************************************/
 
+#ifndef CONFIG_DEBUG
+#  undef CONFIG_SAMA5_ADC_REGDEBUG
+#endif
+
+/* ADC channels 0-3 or 0-4 are not available to the ADC driver if touchscreen
+ * support is enabled.
+ */
+
+#ifdef CONFIG_SAMA5_TOUCHSCREEN
+#  undef CONFIG_SAMA5_ADC_CHAN0
+#  undef CONFIG_SAMA5_ADC_CHAN1
+#  undef CONFIG_SAMA5_ADC_CHAN2
+#  undef CONFIG_SAMA5_ADC_CHAN3
+#  ifdef CONFIG_SAMA5_TOUCHSCREEN_5WIRE
+#    undef CONFIG_SAMA5_ADC_CHAN4
+#  endif
+#endif
+
+/* Do we have any ADC channels enabled?  If not, then the ADC driver may
+ * still need to exist to support the touchscreen.
+ */
+
+#undef SAMA5_ADC_HAVE_CHANNELS
+#if defined(CONFIG_SAMA5_ADC_CHAN0) || defined(CONFIG_SAMA5_ADC_CHAN1) || \
+    defined(CONFIG_SAMA5_ADC_CHAN2) || defined(CONFIG_SAMA5_ADC_CHAN3) || \
+    defined(CONFIG_SAMA5_ADC_CHAN4) || defined(CONFIG_SAMA5_ADC_CHAN5) || \
+    defined(CONFIG_SAMA5_ADC_CHAN6) || defined(CONFIG_SAMA5_ADC_CHAN7) || \
+    defined(CONFIG_SAMA5_ADC_CHAN8) || defined(CONFIG_SAMA5_ADC_CHAN9) || \
+    defined(CONFIG_SAMA5_ADC_CHAN10) || defined(CONFIG_SAMA5_ADC_CHAN11)
+#  define SAMA5_ADC_HAVE_CHANNELS 1
+#elif !defined(CONFIG_SAMA5_TOUCHSCREEN)
+#  error "No ADC channels nor touchscreen"
+#endif
+
 /****************************************************************************
  * Public Types
  ****************************************************************************/
@@ -88,6 +122,35 @@ FAR struct adc_dev_s *sam_adcinitialize(void);
  * Interfaces exported from the ADC to the touchscreen driver
  ****************************************************************************/
 
+/****************************************************************************
+ * Name: sam_adc_getreg
+ *
+ * Description:
+ *  Read any 32-bit register using an absolute address.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_SAMA5_ADC_REGDEBUG
+uint32_t sam_adc_getreg(FAR struct adc_dev_s *, uintptr_t address)
+#else
+#  define sam_adc_getreg(handle,addr) getreg32(addr)
+#endif
+
+/****************************************************************************
+ * Name: sam_adc_putreg
+ *
+ * Description:
+ *  Write to any 32-bit register using an absolute address.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_SAMA5_ADC_REGDEBUG
+void sam_adc_putreg(FAR struct adc_dev_s *dev, uintptr_t address,
+                    uint32_t regval)
+#else
+#  define sam_adc_putreg(handle,addr,val) putreg32(val,addr)
+#endif
+
 #undef EXTERN
 #ifdef __cplusplus
 }
diff --git a/nuttx/arch/arm/src/sama5/sam_touchscreen.c b/nuttx/arch/arm/src/sama5/sam_touchscreen.c
index 3dcdac21f..b46ed8086 100644
--- a/nuttx/arch/arm/src/sama5/sam_touchscreen.c
+++ b/nuttx/arch/arm/src/sama5/sam_touchscreen.c
@@ -94,7 +94,7 @@ enum sam_contact_3
   CONTACT_UP,                   /* Contact lost */
 };
 
-/* This structure describes the results of one ADS7843E sample */
+/* This structure describes the results of one touchscreen sample */
 
 struct sam_sample_s
 {
@@ -105,11 +105,11 @@ struct sam_sample_s
   uint16_t y;                   /* Measured Y position */
 };
 
-/* This structure describes the state of one ADS7843E driver instance */
+/* This structure describes the state of one touchscreen driver instance */
 
 struct sam_dev_s
 {
-  uint8_t nwaiters;             /* Number of threads waiting for ADS7843E data */
+  uint8_t nwaiters;             /* Number of threads waiting for touchscreen data */
   uint8_t id;                   /* Current touch point ID */
   volatile bool penchange;      /* An unreported event is buffered */
   uint16_t threshx;             /* Thresholding X value */
@@ -117,6 +117,7 @@ struct sam_dev_s
   sem_t devsem;                 /* Manages exclusive access to this structure */
   sem_t waitsem;                /* Used to wait for the availability of data */
 
+  struct adc_dev_s *dev;        /* ADC device handle */
   struct work_s work;           /* Supports the interrupt handling "bottom half" */
   struct sam_sample_s sample;   /* Last sampled touch point data */
   WDOG_ID wdog;                 /* Poll the position while the pen is down */
@@ -127,7 +128,7 @@ struct sam_dev_s
    */
 
 #ifndef CONFIG_DISABLE_POLL
-  struct pollfd *fds[CONFIG_ADS7843E_NPOLLWAITERS];
+  struct pollfd *fds[CONFIG_SAMA5_TSD_NPOLLWAITERS];
 #endif
 };
 
@@ -198,14 +199,14 @@ static void sam_notify(FAR struct sam_dev_s *priv)
 
   if (priv->nwaiters > 0)
     {
-      /* After posting this semaphore, we need to exit because the ADS7843E
+      /* After posting this semaphore, we need to exit because the touchscreen
        * is no longer available.
        */
 
       sem_post(&priv->waitsem);
     }
 
-  /* If there are threads waiting on poll() for ADS7843E data to become available,
+  /* If there are threads waiting on poll() for touchscreen data to become available,
    * then wake them up now.  NOTE: we wake up all waiting threads because we
    * do not know that they are going to do.  If they all try to read the data,
    * then some make end up blocking after all.
@@ -242,7 +243,7 @@ static int sam_sample(FAR struct sam_dev_s *priv,
 
   flags = irqsave();
 
-  /* Is there new ADS7843E sample data available? */
+  /* Is there new touchscreen sample data available? */
 
   if (priv->penchange)
     {
@@ -368,10 +369,11 @@ static int sam_schedule(FAR struct sam_dev_s *priv)
 {
   int ret;
 
-  /* Disable further interrupts.  touchscreen ADC interrupts will be re-enabled
-   * after the worker thread executes.
+  /* Disable further touchscreen interrupts.  Touchscreen interrupts will be
+   * re-enabled after the worker thread executes.
    */
-#warning "Missing logic"
+
+  sam_adc_putreg32(priv->dev, SAM_ADC_IDR, ADC_TSD_INTS);
 
   /* Disable the watchdog timer.  It will be re-enabled in the worker thread
    * while the pen remains down.
@@ -545,19 +547,16 @@ static void sam_bottomhalf(FAR void *arg)
   priv->sample.id = priv->id;
   priv->penchange = true;
 
-  /* Notify any waiters that new ADS7843E data is available */
+  /* Notify any waiters that new touchscreen data is available */
 
   sam_notify(priv);
 
-  /* Exit, re-enabling ADS7843E interrupts */
+  /* Exit, re-enabling touchscreen interrupts */
 
 ignored:
+  /* Re-enable touchscreen interrupts. */
 
-  /* Re-enable the PENIRQ interrupts */
-#warning Missing logic
-
-  /* Re-enable the PENIRQ interrupt at the MCU's interrupt controller */
-#warning Missing logic
+  sam_adc_putreg32(priv->dev, SAM_ADC_IER, ADC_TSD_INTS);
 
   /* Release our lock on the state structure */
 
@@ -658,7 +657,7 @@ static ssize_t sam_read(FAR struct file *filep, FAR char *buffer, size_t len)
         }
     }
 
-  /* In any event, we now have sampled ADS7843E data that we can report
+  /* In any event, we now have sampled touchscreen data that we can report
    * to the caller.
    */
 
@@ -870,9 +869,9 @@ errout:
  *
  ****************************************************************************/
 
-int sam_tsd_register(int minor)
+int sam_tsd_register(struct adc_dev_s *dev, int minor)
 {
-  FAR struct sam_dev_s *priv = &g_tsd;
+  struct sam_dev_s *priv = &g_tsd;
   char devname[DEV_NAMELEN];
   int ret;
 
@@ -880,11 +879,12 @@ int sam_tsd_register(int minor)
 
   /* Debug-only sanity checks */
 
-  DEBUGASSERT(minor >= 0 && minor < 100);
+  DEBUGASSERT(dev && minor >= 0 && minor < 100);
 
   /* Initialize the touchscreen device driver instance */
 
   memset(priv, 0, sizeof(struct sam_dev_s));
+  priv->dev     = dev;               /* Save the ADC device handle */
   priv->wdog    = wd_create();       /* Create a watchdog timer */
   priv->threshx = INVALID_THRESHOLD; /* Initialize thresholding logic */
   priv->threshy = INVALID_THRESHOLD; /* Initialize thresholding logic */
@@ -945,20 +945,25 @@ errout_with_priv:
  *
  * Returned Value:
  *   None
- * 
+ *
  ****************************************************************************/
 
 void sam_tsd_interrupt(void)
 {
-  FAR struct sam_dev_s *priv = &g_tsd;
+  struct sam_dev_s *priv = &g_tsd;
   int ret;
 
+  /* Disable further touchscreen interrupts */
+
+  sam_adc_putreg32(priv->dev, SAM_ADC_IDR, ADC_TSD_INTS);
+
   /* Schedule sampling to occur on the worker thread */
 
   ret = sam_schedule(priv);
-
-  /* Clear any pending interrupts and return success */
-#warning Missing logic
+  if (ret < 0)
+    {
+      idbg("ERROR: sam_schedule failed: %d\n", ret);
+    }
   return ret;
 }
 
diff --git a/nuttx/arch/arm/src/sama5/sam_touchscreen.h b/nuttx/arch/arm/src/sama5/sam_touchscreen.h
index 8a68f2206..eebf32a93 100644
--- a/nuttx/arch/arm/src/sama5/sam_touchscreen.h
+++ b/nuttx/arch/arm/src/sama5/sam_touchscreen.h
@@ -79,7 +79,8 @@ extern "C"
  *   /dev/inputN where N is the minor device number
  *
  * Input Parameters:
- *   minor   - The input device minor number
+ *   dev   - The ADC device handle received from sam_adc_initialize()
+ *   minor - The input device minor number
  *
  * Returned Value:
  *   Zero is returned on success.  Otherwise, a negated errno value is
@@ -87,7 +88,7 @@ extern "C"
  *
  ****************************************************************************/
 
-int sam_tsd_register(int minor);
+int sam_tsd_register(FAR struct adc_dev_s *dev, int minor);
 
 /****************************************************************************
  * Interfaces exported from the touchscreen to the ADC driver
@@ -99,14 +100,14 @@ int sam_tsd_register(int minor);
  *   Handles ADC interrupts associated with touchscreen channels
  *
  * Input parmeters:
- *   None
+ *   pending - Current set of pending interrupts being handled
  *
  * Returned Value:
  *   None
- * 
+ *
  ****************************************************************************/
 
-void sam_tsd_interrupt(void);
+void sam_tsd_interrupt(uint32_t pending);
 
 #undef EXTERN
 #ifdef __cplusplus
diff --git a/nuttx/include/nuttx/analog/adc.h b/nuttx/include/nuttx/analog/adc.h
index fe5eb9809..9970f4723 100644
--- a/nuttx/include/nuttx/analog/adc.h
+++ b/nuttx/include/nuttx/analog/adc.h
@@ -129,7 +129,7 @@ struct adc_ops_s
 };
 
 /* This is the device structure used by the driver.  The caller of
- * can_register() must allocate and initialize this structure.  The
+ * adc_register() must allocate and initialize this structure.  The
  * calling logic need only set all fields to zero except:
  *
  *   The elements of 'ad_ops', and 'ad_priv'