More STM32 DAC driver logic

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4186 42af7a65-404d-4744-a932-0658087f49c3

9 files changed, 461 insertions, 78 deletions

diff --git a/nuttx/arch/arm/src/lpc17xx/lpc17_dac.c b/nuttx/arch/arm/src/lpc17xx/lpc17_dac.c
index 4f9a9332c..13ac212f6 100644
--- a/nuttx/arch/arm/src/lpc17xx/lpc17_dac.c
+++ b/nuttx/arch/arm/src/lpc17xx/lpc17_dac.c
@@ -65,7 +65,7 @@
 #include "lpc17_pinconn.h"
 #include "lpc17_dac.h"
 
-#if defined(CONFIG_LPC17_DAC)
+#ifdef CONFIG_LPC17_DAC
 
 /****************************************************************************
  * Private Types
@@ -91,17 +91,17 @@ static int  dac_interrupt(int irq, void *context);
 
 static const struct dac_ops_s g_dacops =
 {
-    .ao_reset =dac_reset,
-    .ao_setup = dac_setup,
-    .ao_shutdown = dac_shutdown,
-    .ao_txint = dac_txint,
-    .ao_send = dac_send,
-    .ao_ioctl = dac_ioctl,
+  .ao_reset =dac_reset,
+  .ao_setup = dac_setup,
+  .ao_shutdown = dac_shutdown,
+  .ao_txint = dac_txint,
+  .ao_send = dac_send,
+  .ao_ioctl = dac_ioctl,
 };
 
 static struct dac_dev_s g_dacdev =
 {
-    .ad_ops = &g_dacops,
+  .ad_ops = &g_dacops,
 };
 
 /****************************************************************************
@@ -114,22 +114,21 @@ static struct dac_dev_s g_dacdev =
 
 static void dac_reset(FAR struct dac_dev_s *dev)
 {
-    irqstate_t flags;
-    uint32_t regval;
+  irqstate_t flags;
+  uint32_t regval;
     
-    flags = irqsave();
+  flags = irqsave();
 
-    regval  = getreg32(LPC17_SYSCON_PCLKSEL0);
-    regval &= ~SYSCON_PCLKSEL0_DAC_MASK;
-    regval |= (SYSCON_PCLKSEL_CCLK8 << SYSCON_PCLKSEL0_DAC_SHIFT);
-    putreg32(regval, LPC17_SYSCON_PCLKSEL0);
+  regval  = getreg32(LPC17_SYSCON_PCLKSEL0);
+  regval &= ~SYSCON_PCLKSEL0_DAC_MASK;
+  regval |= (SYSCON_PCLKSEL_CCLK8 << SYSCON_PCLKSEL0_DAC_SHIFT);
+  putreg32(regval, LPC17_SYSCON_PCLKSEL0);
 
-    //putreg32(DAC_CTRL_DBLBUFEN,LPC17_DAC_CTRL); ?
+  //putreg32(DAC_CTRL_DBLBUFEN,LPC17_DAC_CTRL); ?
 
-    lpc17_configgpio(GPIO_AOUT);
-    
-    irqrestore(flags);
+  lpc17_configgpio(GPIO_AOUT);
 
+  irqrestore(flags);
 }
 
 /* Configure the DAC. This method is called the first time that the DAC
@@ -140,7 +139,7 @@ static void dac_reset(FAR struct dac_dev_s *dev)
 
 static int  dac_setup(FAR struct dac_dev_s *dev)
 {
-    return OK;
+  return OK;
 }
 
 /* Disable the DAC.  This method is called when the DAC device is closed.
@@ -159,17 +158,17 @@ static void dac_txint(FAR struct dac_dev_s *dev, bool enable)
 
 static int  dac_send(FAR struct dac_dev_s *dev, FAR struct dac_msg_s *msg)
 {
-    putreg32((msg->am_data>>16)&0xfffff,LPC17_DAC_CR);
-    dac_txdone(&g_dacdev);
-    return 0;
+  putreg32((msg->am_data>>16)&0xfffff,LPC17_DAC_CR);
+  dac_txdone(&g_dacdev);
+  return 0;
 }
 
 /* All ioctl calls will be routed through this method */
 
 static int  dac_ioctl(FAR struct dac_dev_s *dev, int cmd, unsigned long arg)
 {
-    dbg("Fix me:Not Implemented\n");
-    return 0;
+  dbg("Fix me:Not Implemented\n");
+  return 0;
 }
 
 static int  dac_interrupt(int irq, void *context)
@@ -181,7 +180,7 @@ static int  dac_interrupt(int irq, void *context)
  ****************************************************************************/
 
 /****************************************************************************
- * Name: up_dacinitialize
+ * Name: lpc17_dacinitialize
  *
  * Description:
  *   Initialize the DAC
@@ -191,9 +190,10 @@ static int  dac_interrupt(int irq, void *context)
  *
  ****************************************************************************/
 
-FAR struct dac_dev_s *up_dacinitialize()
+FAR struct dac_dev_s *lpc17_dacinitialize(void)
 {
-    return &g_dacdev;
+  return &g_dacdev;
 }
-#endif
+
+#endif /* CONFIG_LPC17_DAC */
 
diff --git a/nuttx/arch/arm/src/lpc17xx/lpc17_internal.h b/nuttx/arch/arm/src/lpc17xx/lpc17_internal.h
index aa2ddc489..107200e4d 100755
--- a/nuttx/arch/arm/src/lpc17xx/lpc17_internal.h
+++ b/nuttx/arch/arm/src/lpc17xx/lpc17_internal.h
@@ -609,7 +609,7 @@ EXTERN int lpc17_ssp1cmddata(FAR struct spi_dev_s *dev, enum spi_dev_e devid, bo
 #endif
 
 /****************************************************************************
- * Name: ssp_flush
+ * Name: spi_flush
  *
  * Description:
  *   Flush and discard any words left in the RX fifo.  This can be called
@@ -756,6 +756,21 @@ EXTERN void lpc17_dmadump(DMA_HANDLE handle, const struct lpc17_dmaregs_s *regs,
 #endif
 #endif
 
+/****************************************************************************
+ * Name: lpc17_dacinitialize
+ *
+ * Description:
+ *   Initialize the DAC
+ *
+ * Returned Value:
+ *   Valid dac device structure reference on succcess; a NULL on failure
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_LPC17_DAC
+EXTERN FAR struct dac_dev_s *lpc17_dacinitialize(void);
+#endif
+
 #undef EXTERN
 #if defined(__cplusplus)
 }
diff --git a/nuttx/arch/arm/src/stm32/chip/stm32f103ze_pinmap.h b/nuttx/arch/arm/src/stm32/chip/stm32f103ze_pinmap.h
index 3caf54279..8446a2472 100644
--- a/nuttx/arch/arm/src/stm32/chip/stm32f103ze_pinmap.h
+++ b/nuttx/arch/arm/src/stm32/chip/stm32f103ze_pinmap.h
@@ -48,6 +48,65 @@
 
 /* Alternate Pin Functions: */
 
+/* ADC */
+
+#define GPIO_ADC1_IN0       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN0)
+#define GPIO_ADC1_IN1       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN1)
+#define GPIO_ADC1_IN2       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN2)
+#define GPIO_ADC1_IN3       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN3)
+#define GPIO_ADC1_IN4       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN4)
+#define GPIO_ADC1_IN5       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN5)
+#define GPIO_ADC1_IN6       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN6)
+#define GPIO_ADC1_IN7       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN7)
+#define GPIO_ADC1_IN8       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTB|GPIO_PIN0)
+#define GPIO_ADC1_IN9       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTB|GPIO_PIN1)
+#define GPIO_ADC1_IN10      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN0)
+#define GPIO_ADC1_IN11      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN1)
+#define GPIO_ADC1_IN12      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN2)
+#define GPIO_ADC1_IN13      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN3)
+#define GPIO_ADC1_IN14      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN4)
+#define GPIO_ADC1_IN15      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN5)
+
+#define GPIO_ADC2_IN0       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN0)
+#define GPIO_ADC2_IN1       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN1)
+#define GPIO_ADC2_IN2       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN2)
+#define GPIO_ADC2_IN3       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN3)
+#define GPIO_ADC2_IN4       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN4)
+#define GPIO_ADC2_IN5       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN5)
+#define GPIO_ADC2_IN6       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN6)
+#define GPIO_ADC2_IN7       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN7)
+#define GPIO_ADC2_IN8       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTB|GPIO_PIN0)
+#define GPIO_ADC2_IN9       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTB|GPIO_PIN1)
+#define GPIO_ADC2_IN10      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN0)
+#define GPIO_ADC2_IN11      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN1)
+#define GPIO_ADC2_IN12      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN2)
+#define GPIO_ADC2_IN13      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN3)
+#define GPIO_ADC2_IN14      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN4)
+#define GPIO_ADC2_IN15      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN5)
+
+#define GPIO_ADC3_IN0       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN0)
+#define GPIO_ADC3_IN1       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN1)
+#define GPIO_ADC3_IN2       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN2)
+#define GPIO_ADC3_IN3       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTA|GPIO_PIN3)
+#define GPIO_ADC3_IN4       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTF|GPIO_PIN6)
+#define GPIO_ADC3_IN5       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTF|GPIO_PIN7)
+#define GPIO_ADC3_IN6       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTF|GPIO_PIN8)
+#define GPIO_ADC3_IN7       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTF|GPIO_PIN9)
+#define GPIO_ADC3_IN8       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTF|GPIO_PIN10)
+#define GPIO_ADC3_IN10      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN0)
+#define GPIO_ADC3_IN11      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN1)
+#define GPIO_ADC3_IN12      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN2)
+#define GPIO_ADC3_IN13      (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTC|GPIO_PIN3)
+
+/* DAC - "Once the DAC channelx is enabled, the corresponding GPIO pin
+ * (PA4 or PA5) is automatically connected to the analog converter output
+ * (DAC_OUTx). In order to avoid parasitic consumption, the PA4 or PA5 pin
+ * should first be configured to analog (AIN)."
+ */
+
+#define GPIO_DAC_OUT1       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PORTF|GPIO_PIN10)
+#define GPIO_DAC_OUT2       (GPIO_ALT|GPIO_CNF_ANALOGIN|GPIO_MODE_INPUT|GPIO_PIN10)
+
 /* TIMERS */
 
 #if defined(CONFIG_STM32_TIM1_FULL_REMAP)
diff --git a/nuttx/arch/arm/src/stm32/chip/stm32f40xxx_pinmap.h b/nuttx/arch/arm/src/stm32/chip/stm32f40xxx_pinmap.h
index cd0dbd196..50c49cdbc 100644
--- a/nuttx/arch/arm/src/stm32/chip/stm32f40xxx_pinmap.h
+++ b/nuttx/arch/arm/src/stm32/chip/stm32f40xxx_pinmap.h
@@ -68,6 +68,58 @@
  * pins in this file.
  */
 
+/* ADC */
+
+#define GPIO_ADC1_IN0         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN0)
+#define GPIO_ADC1_IN1         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN1)
+#define GPIO_ADC1_IN2         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN2)
+#define GPIO_ADC1_IN3         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN3)
+#define GPIO_ADC1_IN4         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN4)
+#define GPIO_ADC1_IN5         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN5)
+#define GPIO_ADC1_IN6         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN6)
+#define GPIO_ADC1_IN7         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN7)
+#define GPIO_ADC1_IN8         (GPIO_ANALOG|GPIO_PORTB|GPIO_PIN0)
+#define GPIO_ADC1_IN9         (GPIO_ANALOG|GPIO_PORTB|GPIO_PIN1)
+#define GPIO_ADC1_IN10        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN0)
+#define GPIO_ADC1_IN11        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN1)
+#define GPIO_ADC1_IN12        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN2)
+#define GPIO_ADC1_IN13        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN3)
+#define GPIO_ADC1_IN14        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN4)
+#define GPIO_ADC1_IN15        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN5)
+
+#define GPIO_ADC2_IN0         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN0)
+#define GPIO_ADC2_IN1         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN1)
+#define GPIO_ADC2_IN2         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN2)
+#define GPIO_ADC2_IN3         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN3)
+#define GPIO_ADC2_IN4         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN4)
+#define GPIO_ADC2_IN5         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN5)
+#define GPIO_ADC2_IN6         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN6)
+#define GPIO_ADC2_IN7         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN7)
+#define GPIO_ADC2_IN8         (GPIO_ANALOG|GPIO_PORTB|GPIO_PIN0)
+#define GPIO_ADC2_IN9         (GPIO_ANALOG|GPIO_PORTB|GPIO_PIN1)
+#define GPIO_ADC2_IN10        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN0)
+#define GPIO_ADC2_IN11        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN1)
+#define GPIO_ADC2_IN12        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN2)
+#define GPIO_ADC2_IN13        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN3)
+#define GPIO_ADC2_IN14        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN4)
+#define GPIO_ADC2_IN15        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN5)
+
+#define GPIO_ADC3_IN0         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN0)
+#define GPIO_ADC3_IN1         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN1)
+#define GPIO_ADC3_IN2         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN2)
+#define GPIO_ADC3_IN3         (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN3)
+#define GPIO_ADC3_IN4         (GPIO_ANALOG|GPIO_PORTF|GPIO_PIN6)
+#define GPIO_ADC3_IN5         (GPIO_ANALOG|GPIO_PORTF|GPIO_PIN7)
+#define GPIO_ADC3_IN6         (GPIO_ANALOG|GPIO_PORTF|GPIO_PIN8)
+#define GPIO_ADC3_IN7         (GPIO_ANALOG|GPIO_PORT |GPIO_PIN9)
+#define GPIO_ADC3_IN9         (GPIO_ANALOG|GPIO_PORTF|GPIO_PIN3)
+#define GPIO_ADC3_IN10        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN0)
+#define GPIO_ADC3_IN11        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN1)
+#define GPIO_ADC3_IN12        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN2)
+#define GPIO_ADC3_IN13        (GPIO_ANALOG|GPIO_PORTC|GPIO_PIN3)
+#define GPIO_ADC3_IN14        (GPIO_ANALOG|GPIO_PORTF|GPIO_PIN4)
+#define GPIO_ADC3_IN15        (GPIO_ANALOG|GPIO_PORTF|GPIO_PIN5)
+
 /* CAN */
 
 #define GPIO_CAN1_RX_1        (GPIO_ALT|GPIO_AF9|GPIO_PORTA|GPIO_PIN11)
@@ -84,6 +136,15 @@
 #define GPIO_CAN2_TX_1        (GPIO_ALT|GPIO_AF9|GPIO_PORTB|GPIO_PIN13)
 #define GPIO_CAN2_TX_2        (GPIO_ALT|GPIO_AF9|GPIO_PORTB|GPIO_PIN6)
 
+/* DAC -" Once the DAC channelx is enabled, the corresponding GPIO pin
+ * (PA4 or PA5) is automatically connected to the analog converter output
+ * (DAC_OUTx). In order to avoid parasitic consumption, the PA4 or PA5 pin
+ * should first be configured to analog (AIN)".
+ */
+
+#define GPIO_DAC1_OUT          (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN4)
+#define GPIO_DAC2_OUT          (GPIO_ANALOG|GPIO_PORTA|GPIO_PIN5)
+
 /* Digital Camera Interface (DCMI) */
 
 #define GPIO_DCMI_D0_1        (GPIO_ALT|GPIO_AF13|GPIO_PORTA|GPIO_PIN9)
diff --git a/nuttx/arch/arm/src/stm32/stm32_dac.c b/nuttx/arch/arm/src/stm32/stm32_dac.c
index a7d46707c..09cdb76f1 100644
--- a/nuttx/arch/arm/src/stm32/stm32_dac.c
+++ b/nuttx/arch/arm/src/stm32/stm32_dac.c
@@ -61,9 +61,8 @@
 #ifdef CONFIG_DAC
 
 /****************************************************************************
- * Private Types
+ * Pre-processor Definitions
  ****************************************************************************/
-
 /* Configuration ************************************************************/
 /* Up to 2 DAC interfaces are supported */
 
@@ -78,8 +77,32 @@
 #if defined(CONFIG_STM32_DAC1) || defined(CONFIG_STM32_DAC2)
 
 /****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/* This structure represents the internal state of the single STM32 DAC block */
+
+struct stm32_dac_s
+{
+  uint8_t  init   : 1; /* True, the DAC block has been initialized */
+};
+
+/* This structure represents the internal state of one STM32 DAC channel */
+
+struct stm32_chan_s
+{
+  uint8_t  inuse  : 1; /* True, the driver is in use and not available */
+  uint8_t  intf;       /* DAC zero-based interface number (0 or 1) */
+};
+
+/****************************************************************************
  * Private Function Prototypes
  ****************************************************************************/
+/* DAC Register access */
+
+static uint32_t dac_getreg(struct stm32_chan_s *chan, int offset);
+static void dac_putreg(struct stm32_chan_s *chan, int offset, uint32_t value);
+
 /* Interrupt handler */
 
 #ifdef CONFIG_STM32_STM32F40XX
@@ -96,6 +119,11 @@ static int  dac_send(FAR struct dac_dev_s *dev, FAR struct dac_msg_s *msg);
 static int  dac_ioctl(FAR struct dac_dev_s *dev, int cmd, unsigned long arg);
 static int  dac_interrupt(int irq, void *context);
 
+/* Initialization */
+
+static int  dac_chaninit(struct stm32_chan_s *chan);
+static int  dac_blockinit(void);
+
 /****************************************************************************
  * Private Data
  ****************************************************************************/
@@ -110,16 +138,79 @@ static const struct dac_ops_s g_dacops =
   .ao_ioctl    = dac_ioctl,
 };
 
-static struct dac_dev_s g_dacdev =
+#ifdef CONFIG_STM32_DAC1
+static struct stm32_chan_s g_dac1priv =
+{
+  .intf       = 0;
+}
+
+static struct dac_dev_s g_dac1dev =
+{
+  .ad_ops  = &g_dacops,
+  .ad_priv = &g_dac1priv,
+};
+#endif
+
+#ifdef CONFIG_STM32_DAC2
+static struct stm32_chan_s g_dac2priv =
+{
+  .intf       = 1;
+}
+
+static struct dac_dev_s g_dac2dev =
 {
-  .ad_ops = &g_dacops,
+  .ad_ops  = &g_dacops,
+  .ad_priv = &g_dac2priv,
 };
+#endif
+
+static struct stm32_dac_s g_dacblock; 
 
 /****************************************************************************
  * Private Functions
  ****************************************************************************/
 
 /****************************************************************************
+ * Name: dac_getreg
+ *
+ * Description:
+ *   Read the value of an DAC register.
+ *
+ * Input Parameters:
+ *   chan - A reference to the DAC block status
+ *   offset - The offset to the register to read
+ *
+ * Returned Value:
+ *   The current contents of the specified register
+ *
+ ****************************************************************************/
+
+static uint32_t dac_getreg(struct stm32_chan_s *chan, int offset)
+{
+  return getreg32(chan->base + offset);
+}
+
+/****************************************************************************
+ * Name: dac_getreg
+ *
+ * Description:
+ *   Read the value of an DAC register.
+ *
+ * Input Parameters:
+ *   chan - A reference to the DAC block status
+ *   offset - The offset to the register to read
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+static void dac_putreg(struct stm32_chan_s *chan, int offset, uint32_t value)
+{
+  putreg32(value, chan->base + offset);
+}
+
+/****************************************************************************
  * Name: dac_interrupt
  *
  * Description:
@@ -129,6 +220,7 @@ static struct dac_dev_s g_dacdev =
  * Input Parameters:
  *
  * Returned Value:
+ *   OK
  *
  ****************************************************************************/
 
@@ -143,12 +235,15 @@ static int dac_interrupt(int irq, void *context)
  * Name: dac_reset
  *
  * Description:
- *   Reset the DAC device.  Called early to initialize the hardware. This
+ *   Reset the DAC channel.  Called early to initialize the hardware. This
  *   is called, before dac_setup() and on error conditions.
  *
+ *   NOTE:  DAC reset will reset both DAC channels!
+ *
  * Input Parameters:
  *
  * Returned Value:
+ *   None
  *
  ****************************************************************************/
 
@@ -156,11 +251,11 @@ static void dac_reset(FAR struct dac_dev_s *dev)
 {
   irqstate_t flags;
   uint32_t regval;
-    
-  flags = irqsave();
 
-# warning "Missing logic"
-    
+  flags   = irqsave();
+
+#warning "Missing logic"
+
   irqrestore(flags);
 }
 
@@ -176,6 +271,7 @@ static void dac_reset(FAR struct dac_dev_s *dev)
  * Input Parameters:
  *
  * Returned Value:
+ *   Zero on success; a negated errno value on failure.
  *
  ****************************************************************************/
 
@@ -195,6 +291,7 @@ static int dac_setup(FAR struct dac_dev_s *dev)
  * Input Parameters:
  *
  * Returned Value:
+ *   None
  *
  ****************************************************************************/
 
@@ -212,6 +309,7 @@ static void dac_shutdown(FAR struct dac_dev_s *dev)
  * Input Parameters:
  *
  * Returned Value:
+ *   None
  *
  ****************************************************************************/
 
@@ -229,6 +327,7 @@ static void dac_txint(FAR struct dac_dev_s *dev, bool enable)
  * Input Parameters:
  *
  * Returned Value:
+ *   Zero on success; a negated errno value on failure.
  *
  ****************************************************************************/
 
@@ -247,6 +346,7 @@ static int dac_send(FAR struct dac_dev_s *dev, FAR struct dac_msg_s *msg)
  * Input Parameters:
  *
  * Returned Value:
+ *   Zero on success; a negated errno value on failure.
  *
  ****************************************************************************/
 
@@ -256,6 +356,82 @@ static int  dac_ioctl(FAR struct dac_dev_s *dev, int cmd, unsigned long arg)
 }
 
 /****************************************************************************
+ * Name: dac_ioctl
+ *
+ * Description:
+ *   All ioctl calls will be routed through this method.
+ *
+ * Input Parameters:
+ *
+ * Returned Value:
+ *   Zero on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+static int dac_chaninit(struct stm32_chan_s *chan)
+{
+  /* Is the selected channel already in-use? */
+
+  if (chan->inuse)
+    {
+      /* Yes.. then return EBUSY */
+
+      return -EBUSY;
+    }
+
+  /* Mark the DAC channel "in-use" */
+
+  chan->inuse = 1;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: dac_ioctl
+ *
+ * Description:
+ *   All ioctl calls will be routed through this method.
+ *
+ * Input Parameters:
+ *
+ * Returned Value:
+ *   Zero on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+static int dac_blockinit(void)
+{
+  irqstate_t flags;
+  uint32_t regval;
+
+  /* Has the DMA block already been initialized? */
+
+  if (g_dacblock.init)
+    {
+      /* Yes.. then return success  We only have to do this once */
+
+      return OK;
+    }
+
+  /* Put the entire DAC block in reset state */
+
+  flags   = irqsave();
+  regval  = getreg32(STM32_RCC_APB1RSTR);
+  regval |= RCC_APB1RSTR_DACRST
+  putreg32(regval, STM32_RCC_APB1RSTR);
+
+  /* Take the DAC out of reset state */
+
+  regval &= ~RCC_APB1RSTR_DACRST
+  putreg32(regval, STM32_RCC_APB1RSTR);
+  irqrestore(flags);
+
+  /* Mark the DAC block as initialized */
+
+  g_dacblock.init = 1;
+  return OK;
+}
+
+/****************************************************************************
  * Public Functions
  ****************************************************************************/
 
@@ -263,19 +439,67 @@ static int  dac_ioctl(FAR struct dac_dev_s *dev, int cmd, unsigned long arg)
  * Name: stm32_dacinitialize
  *
  * Description:
- *   Initialize the DAC
+ *   Initialize the DAC.
  *
  * Input Parameters:
  *   intf - The DAC interface number.
  *
  * Returned Value:
- *   Valid dac device structure reference on succcess; a NULL on failure
+ *   Valid dac device structure reference on succcess; a NULL on failure.
+ *
+ * Assumptions:
+ *   1. Clock to the DAC block has enabled,
+ *   2. Board-specific logic has already configured 
  *
  ****************************************************************************/
 
 FAR struct dac_dev_s *stm32_dacinitialize(int intf)
 {
-  return &g_dacdev;
+  FAR struct dac_dev_s    *dev;
+  FAR struct stm32_chan_s *chan;
+  int ret;
+  
+#ifdef CONFIG_STM32_DAC1
+  if (intf == 1)
+    {
+      avdbg("DAC1 Selected\n");
+      dev = &g_dacdev1;
+    }
+  else
+#endif
+#ifdef CONFIG_STM32_DAC2
+  if (intf == 2)
+    {
+      avdbg("DAC2 Selected\n");
+      dev = &g_dac2dev;
+    }
+  else
+#endif
+    {
+      adbg("No such DAC interface: %d\n", intf);
+      return NULL;
+    }
+
+  /* Make sure that the DAC block has been initialized */
+
+  ret = dac_blockinit();
+  if (ret < 0)
+    {
+      adbg("Failed to initialize the DAC block: %d\n", ret);
+      return ret;
+    }
+
+  /* Configure the selected DAC channel */
+
+  chan = dev->ad_priv;
+  ret  = dac_chaninit(chan);
+  if (ret < 0)
+    {
+      adbg("Failed to initialize DAC channel %d: %d\n", intf, ret);
+      return ret;
+    }
+
+  return dev;
 }
 
 #endif /* CONFIG_STM32_DAC1 || CONFIG_STM32_DAC2 */
diff --git a/nuttx/arch/arm/src/stm32/stm32f10xxx_rcc.c b/nuttx/arch/arm/src/stm32/stm32f10xxx_rcc.c
index 07dda8a59..9976e4870 100644
--- a/nuttx/arch/arm/src/stm32/stm32f10xxx_rcc.c
+++ b/nuttx/arch/arm/src/stm32/stm32f10xxx_rcc.c
@@ -298,7 +298,7 @@ static inline void rcc_enableapb1(void)
   regval |= RCC_APB1ENR_PWREN;
 #endif
 
-#if CONFIG_STM32_DAC
+#ifdefined (CONFIG_STM32_DAC1) || defined(CONFIG_STM32_DAC2)
   /* DAC interface clock enable */
 
   regval |= RCC_APB1ENR_DACEN;
diff --git a/nuttx/arch/arm/src/stm32/stm32f40xxx_rcc.c b/nuttx/arch/arm/src/stm32/stm32f40xxx_rcc.c
index e06a84d65..4b8a16790 100644
--- a/nuttx/arch/arm/src/stm32/stm32f40xxx_rcc.c
+++ b/nuttx/arch/arm/src/stm32/stm32f40xxx_rcc.c
@@ -431,7 +431,7 @@ static inline void rcc_enableapb1(void)
 
   regval |= RCC_APB1ENR_PWREN;
 
-#if CONFIG_STM32_DAC
+#ifdefined (CONFIG_STM32_DAC1) || defined(CONFIG_STM32_DAC2)
   /* DAC interface clock enable */
 
   regval |= RCC_APB1ENR_DACEN;
diff --git a/nuttx/drivers/analog/dac.c b/nuttx/drivers/analog/dac.c
index a5f4c1473..b283a5bf5 100644
--- a/nuttx/drivers/analog/dac.c
+++ b/nuttx/drivers/analog/dac.c
@@ -296,17 +296,17 @@ static ssize_t dac_write(FAR struct file *filep, FAR const char *buffer, size_t
    */
 
   if (buflen % 5 ==0 )
-	msglen=5;
+    msglen=5;
   else if (buflen % 4 ==0 )
-	msglen=4;
+    msglen=4;
   else if (buflen % 3 ==0 )
-	msglen=3;
+    msglen=3;
   else if (buflen % 2 ==0 )
-	msglen=2;
+    msglen=2;
   else if (buflen == 1)
-	msglen=1;
+    msglen=1;
   else
-	msglen=5;
+    msglen=5;
 
   while ((buflen - nsent) >= msglen )
     {
@@ -369,35 +369,36 @@ static ssize_t dac_write(FAR struct file *filep, FAR const char *buffer, size_t
       /* We get here if there is space at the end of the FIFO.  Add the new
        * CAN message at the tail of the FIFO.
        */
-	 if(msglen==5)
+
+     if (msglen==5)
      {
-		msg    = (FAR struct dac_msg_s *)&buffer[nsent];
-		memcpy(&fifo->af_buffer[fifo->af_tail], msg, msglen);
+        msg    = (FAR struct dac_msg_s *)&buffer[nsent];
+        memcpy(&fifo->af_buffer[fifo->af_tail], msg, msglen);
      }
      else if(msglen == 4)
      {
-		 fifo->af_buffer[fifo->af_tail].am_channel=buffer[nsent];
-		 fifo->af_buffer[fifo->af_tail].am_data=*(uint32_t *)&buffer[nsent];
-		 fifo->af_buffer[fifo->af_tail].am_data&=0xffffff00;
-	 }
+         fifo->af_buffer[fifo->af_tail].am_channel=buffer[nsent];
+         fifo->af_buffer[fifo->af_tail].am_data=*(uint32_t *)&buffer[nsent];
+         fifo->af_buffer[fifo->af_tail].am_data&=0xffffff00;
+     }
      else if(msglen == 3)
      {
-		 fifo->af_buffer[fifo->af_tail].am_channel=buffer[nsent];
-		 fifo->af_buffer[fifo->af_tail].am_data=(*(uint16_t *)&buffer[nsent+1]);
-		 fifo->af_buffer[fifo->af_tail].am_data<<=16;
-	 }
+         fifo->af_buffer[fifo->af_tail].am_channel=buffer[nsent];
+         fifo->af_buffer[fifo->af_tail].am_data=(*(uint16_t *)&buffer[nsent+1]);
+         fifo->af_buffer[fifo->af_tail].am_data<<=16;
+     }
      else if(msglen == 2)
      {
-		 fifo->af_buffer[fifo->af_tail].am_channel=0;
-		 fifo->af_buffer[fifo->af_tail].am_data=(*(uint16_t *)&buffer[nsent]);
-		 fifo->af_buffer[fifo->af_tail].am_data<<=16;
-	 }
+         fifo->af_buffer[fifo->af_tail].am_channel=0;
+         fifo->af_buffer[fifo->af_tail].am_data=(*(uint16_t *)&buffer[nsent]);
+         fifo->af_buffer[fifo->af_tail].am_data<<=16;
+     }
      else if(msglen == 1)
      {
-		 fifo->af_buffer[fifo->af_tail].am_channel=0;
-		 fifo->af_buffer[fifo->af_tail].am_data=buffer[nsent];
-		 fifo->af_buffer[fifo->af_tail].am_data<<=24;
-	 }
+         fifo->af_buffer[fifo->af_tail].am_channel=0;
+         fifo->af_buffer[fifo->af_tail].am_data=buffer[nsent];
+         fifo->af_buffer[fifo->af_tail].am_data<<=24;
+     }
       /* Increment the tail of the circular buffer */
 
       fifo->af_tail = nexttail;
diff --git a/nuttx/include/nuttx/analog/dac.h b/nuttx/include/nuttx/analog/dac.h
index 7359e6c3a..23cbb9941 100644
--- a/nuttx/include/nuttx/analog/dac.h
+++ b/nuttx/include/nuttx/analog/dac.h
@@ -6,6 +6,7 @@
  *   History: 0.1 2011-08-04 initial version
  *
  * Derived from include/nuttx/can.h
+ *
  *   Copyright (C) 2008, 2009 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
  *
@@ -71,10 +72,11 @@
 /************************************************************************************
  * Public Types
  ************************************************************************************/
+
 struct dac_msg_s
 {
-  uint8_t      am_channel;                  /* The 8-bit DAC Channel */
-  int32_t      am_data;                    /* DAC convert result (4 bytes) */
+  uint8_t      am_channel;               /* The 8-bit DAC Channel */
+  int32_t      am_data;                  /* DAC convert result (4 bytes) */
 };
 
 struct dac_fifo_s
@@ -138,12 +140,12 @@ struct dac_ops_s
 
 struct dac_dev_s
 {
-  uint8_t              ad_ocount;        /* The number of times the device has been opened */
-  uint8_t              ad_nchannel;      /* Number of dac channel */
-  sem_t                ad_closesem;      /* Locks out new opens while close is in progress */
-  struct dac_fifo_s    ad_xmit;          /* Describes receive FIFO */
-  const struct dac_ops_s *ad_ops;    /* Arch-specific operations */
-  void                *ad_priv;          /* Used by the arch-specific logic */
+  uint8_t                 ad_ocount;   /* The number of times the device has been opened */
+  uint8_t                 ad_nchannel; /* Number of dac channel */
+  sem_t                   ad_closesem; /* Locks out new opens while close is in progress */
+  struct dac_fifo_s       ad_xmit;     /* Describes receive FIFO */
+  const struct dac_ops_s *ad_ops;      /* Arch-specific operations */
+  void                   *ad_priv;     /* Used by the arch-specific logic */
 };
 
 /************************************************************************************
@@ -157,12 +159,21 @@ struct dac_dev_s
 #if defined(__cplusplus)
 extern "C" {
 #endif
+
 /************************************************************************************
  * Name: dac_register
  *
  * Description:
  *   Register a dac driver.
  *
+ * Input Parameters:
+ *    path - The full path to the DAC device to be registered.  This could be, as an
+ *      example, "/dev/dac0"
+ *    dev - An instance of the device-specific DAC interface
+ *
+ * Returned Value:
+ *    Zero on success; A negated errno value on failure.
+ *
  ************************************************************************************/
 
 int dac_register(FAR const char *path, FAR struct dac_dev_s *dev);
@@ -173,14 +184,26 @@ int dac_register(FAR const char *path, FAR struct dac_dev_s *dev);
  * Description:
  *   Called from the DAC interrupt handler at the completion of a send operation.
  *
+ * Input Parameters:
+ *    dev - An instance of the device-specific DAC interface
+ *
  * Return:
  *   OK on success; a negated errno on failure.
  *
  ************************************************************************************/
+
 int dac_txdone(FAR struct dac_dev_s *dev);
 
+/************************************************************************************
+ * DAC Initialization functions
+ *
+ * Architecture-specific versions will have prototypes in architect-specific header
+ * files.  Common DAC implementations in drivers/analog will have prototypes listed
+ * below.
+ *
+ ************************************************************************************/
+
 FAR struct dac_dev_s *up_ad5410initialize(FAR struct spi_dev_s *spi, unsigned int devno);
-FAR struct dac_dev_s *up_dacinitialize();
 
 #if defined(__cplusplus)
 }