/****************************************************************************
 * arch/arm/src/stm32/stm32_adc.c
 *
 *   Copyright (C) 2011 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *           Diego Sanchez <dsanchez@nx-engineering.com>
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/
 
/****************************************************************************
 * Included Files
 ****************************************************************************/
 
#include <nuttx/config.h>

#include <stdio.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <semaphore.h>
#include <errno.h>
#include <debug.h>

#include <arch/board/board.h>
#include <nuttx/arch.h>
#include <nuttx/analog/adc.h>

#include "up_internal.h"
#include "up_arch.h"

#include "chip.h"
#include "stm32_internal.h"
#include "stm32_adc.h"

#ifdef CONFIG_ADC

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/
/* Configuration ************************************************************/
/* Up to 3 ADC interfaces are supported */

#if STM32_NADC < 3
#  undef CONFIG_STM32_ADC3
#endif

#if STM32_NADC < 2
#  undef CONFIG_STM32_ADC2
#endif

#if STM32_NADC < 1
#  undef CONFIG_STM32_ADC1
#endif

#if defined(CONFIG_STM32_ADC1) || defined(CONFIG_STM32_ADC2) || defined(CONFIG_STM32_ADC3)

/* ADC interrupts */

#ifdef CONFIG_STM32_STM32F10XX
#  define ADC_SR_ALLINTS (ADC_SR_AWD | ADC_SR_EOC | ADC_SR_JEOC)
#else
#  define ADC_SR_ALLINTS (ADC_SR_AWD | ADC_SR_EOC | ADC_SR_JEOC | ADC_SR_OVR)
#endif

#ifdef CONFIG_STM32_STM32F10XX
#  define ADC_CR1_ALLINTS (ADC_CR1_AWDIE | ADC_CR1_EOCIE | ADC_CR1_JEOCIE)
#else
#  define ADC_CR1_ALLINTS (ADC_CR1_AWDIE | ADC_CR1_EOCIE | ADC_CR1_JEOCIE | ADC_CR1_OVRIE)
#endif

/****************************************************************************
 * Private Types
 ****************************************************************************/

/* This structure describes the state of one ADC block */

struct stm32_dev_s
{
  int      irq;       /* Interrupt generated by this ADC block */
  xcpt_t   isr;       /* Interrupt handler for this ADC block */
  uint32_t base;      /* Base address of registers unique to this ADC block */

  int32_t  buf[8];
  uint8_t  count[8];
};

/****************************************************************************
 * Private Function Prototypes
 ****************************************************************************/

/* ADC Register access */

static uint32_t adc_getreg(struct stm32_dev_s *priv, int offset);
static void     adc_putreg(struct stm32_dev_s *priv, int offset, uint32_t value);

/* ADC Interrupt Handler */

static void adc_interrupt(FAR struct stm32_dev_s *priv);
#if defined(CONFIG_STM32_STM32F10XX) && (defined(CONFIG_STM32_ADC1) || defined(CONFIG_STM32_ADC2))
static int adc12_interrupt(int irq, void *context)
#endif
#ifdef CONFIG_STM32_STM32F10XX && defined (CONFIG_STM32_ADC3)
static int adc3_interrupt(int irq, void *context)
#endif
#ifdef CONFIG_STM32_STM32F40XX
static int adc123_interrupt(int irq, void *context)
#endif

/* ADC Driver Methods */

static void adc_reset(FAR struct adc_dev_s *dev);
static int  adc_setup(FAR struct adc_dev_s *dev);
static void adc_shutdown(FAR struct adc_dev_s *dev);
static void adc_rxint(FAR struct adc_dev_s *dev, bool enable);
static int  adc_ioctl(FAR struct adc_dev_s *dev, int cmd, unsigned long arg);

/****************************************************************************
 * Private Data
 ****************************************************************************/

/* ADC interface operations */

static const struct adc_ops_s g_adcops =
{
  .ao_reset    = adc_reset,
  .ao_setup    = adc_setup,
  .ao_shutdown = adc_shutdown,
  .ao_rxint    = adc_rxint,
  .ao_ioctl    = adc_ioctl,
};

/* ADC1 state */

#ifdef CONFIG_STM32_ADC1
static struct stm32_dev_s g_adcpriv1 =
{
#ifdef CONFIG_STM32_STM32F10XX
  .irq         = STM32_IRQ_ADC12,
  .isr         = adc12_interrupt,
#else
  .irq         = STM32_IRQ_ADC,
  .isr         = adc123_interrupt,
#endif
  .base        = STM32_ADC1_BASE,
};

static struct adc_dev_s g_adcdev1 =
{
  .ad_ops = &g_adcops,
  .ad_priv= &g_adcpriv1,
};
#endif

/* ADC2 state */

#ifdef CONFIG_STM32_ADC2
static struct stm32_dev_s g_adcpriv2 =
{
#ifdef CONFIG_STM32_STM32F10XX
  .irq         = STM32_IRQ_ADC12,
  .isr         = adc12_interrupt,
#else
  .irq         = STM32_IRQ_ADC,
  .isr         = adc123_interrupt,
#endif
  .base        = STM32_ADC2_BASE,
};

static struct adc_dev_s g_adcdev2 =
{
  .ad_ops = &g_adcops,
  .ad_priv= &g_adcpriv2,
};
#endif

/* ADC3 state */

#ifdef CONFIG_STM32_ADC3
static struct stm32_dev_s g_adcpriv3 =
{
#ifdef CONFIG_STM32_STM32F10XX
  .irq         = STM32_IRQ_ADC3,
  .isr         = adc3_interrupt,
#else
  .irq         = STM32_IRQ_ADC,
  .isr         = adc123_interrupt,
#endif
  .base        = STM32_ADC3_BASE,
};

static struct adc_dev_s g_adcdev3 =
{
  .ad_ops = &g_adcops,
  .ad_priv= &g_adcpriv3,
};
#endif

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Name: adc_getreg
 *
 * Description:
 *   Read the value of an ADC register.
 *
 * Input Parameters:
 *   priv - A reference to the ADC block status
 *   offset - The offset to the register to read
 *
 * Returned Value:
 *
 ****************************************************************************/

static uint32_t adc_getreg(struct stm32_dev_s *priv, int offset)
{
  return getreg32(priv->base + offset);
}

/****************************************************************************
 * Name: adc_getreg
 *
 * Description:
 *   Read the value of an ADC register.
 *
 * Input Parameters:
 *   priv - A reference to the ADC block status
 *   offset - The offset to the register to read
 *
 * Returned Value:
 *
 ****************************************************************************/

static void adc_putreg(struct stm32_dev_s *priv, int offset, uint32_t value)
{
  putreg32(value, priv->base + offset);
}

/****************************************************************************
 * Name: adc_reset
 *
 * Description:
 *   Reset the ADC device.  Called early to initialize the hardware. This
 *   is called, before adc_setup() and on error conditions.
 *
 * Input Parameters:
 *
 * Returned Value:
 *
 ****************************************************************************/

static void adc_reset(FAR struct adc_dev_s *dev)
{
  FAR struct stm32_dev_s *priv = (FAR struct stm32_dev_s *)dev->ad_priv;
  irqstate_t flags;
  uint32_t regval;

  flags = irqsave();

  /* Initialize the ADC data structures */

  /* ADC1 CR Configuration */

  regval  = adc_getreg(priv, STM32_ADC_CR1_OFFSET);
  regval &= ~ADC_CR1_DUALMOD_MASK;
  regval &= ~ADC_CR1_SCAN;   /* Clear DUALMODE and SCAN bits */
  adc_putreg(priv, STM32_ADC_CR1_OFFSET, regval);

  /* Initialize the ADC_Mode (ADC_Mode_Independent)  */

  regval  = adc_getreg(priv, STM32_ADC_CR1_OFFSET);
  regval |= ADC_CR1_IND;

  /* Initialize the ADC_CR1_SCAN member DISABLE */

  regval &= ~ADC_CR1_SCAN;
  adc_putreg(priv, STM32_ADC_CR1_OFFSET, regval);

  /* ADC1 CR2 Configuration */
  /* Clear CONT, ALIGN and EXTTRIG bits */

  regval  = adc_getreg(priv, STM32_ADC_CR2_OFFSET);
  regval &= ~ADC_CR2_CONT;
  regval &= ~ADC_CR2_ALIGN;
  regval &= ~ADC_CR2_EXTSEL_MASK;
  adc_putreg(priv, STM32_ADC_CR2_OFFSET, regval);

  /* Set CONT, ALIGN and EXTTRIG bits */
  /* Initialize the ALIGN: Data alignment Right */

  regval  = adc_getreg(priv, STM32_ADC_CR2_OFFSET);
  regval &= ~ADC_CR2_ALIGN;

  /* Initialize the External event select "Timer CC1 event" */

  regval &= ~ADC_CR2_EXTSEL_MASK;

  /* Initialize the ADC_ContinuousConvMode "Single conversion mode" */

  regval &= ~ADC_CR2_CONT;
  adc_putreg(priv, STM32_ADC_CR2_OFFSET, regval);

  /* ADC1 SQR1 Configuration */

  regval  = adc_getreg(priv, STM32_ADC_SQR1_OFFSET);
  regval &= ~ADC_SQR1_L_MASK; /* L = 0000: 1 conversion */
  adc_putreg(priv, STM32_ADC_SQR_OFFSET1, regval);

  irqrestore(flags);  
}

/****************************************************************************
 * Name: adc_setup
 *
 * Description:
 *   Configure the ADC. This method is called the first time that the ADC
 *   device is opened.  This will occur when the port is first opened.
 *   This setup includes configuring and attaching ADC interrupts.  Interrupts
 *   are all disabled upon return.
 *
 * Input Parameters:
 *
 * Returned Value:
 *
 ****************************************************************************/

static int adc_setup(FAR struct adc_dev_s *dev)
{
  FAR struct stm32_dev_s *priv = (FAR struct stm32_dev_s *)dev->ad_priv;
  int ret;
  uint32_t regval = 0;
  int i;
  /* Attach the ADC interrupt */

  ret = irq_attach(priv->irq, priv->isr);
  if (ret == OK)
    {
      for (i = 0; i < 8; i++)
      {
        priv->buf[i]   = 0;
        priv->count[i] = 0;
      }
      
      /* Enable the ADC interrupt */

      up_enable_irq(priv->irq);
    }
  return ret;
}

/****************************************************************************
 * Name: adc_shutdown
 *
 * Description:
 *   Disable the ADC.  This method is called when the ADC device is closed.
 *   This method reverses the operation the setup method.
 *
 * Input Parameters:
 *
 * Returned Value:
 *
 ****************************************************************************/

static void adc_shutdown(FAR struct adc_dev_s *dev)
{
  FAR struct stm32_dev_s *priv = (FAR struct stm32_dev_s *)dev->ad_priv;

  /* Disable ADC interrupts and detach the ADC interrupt handler */

  up_disable_irq(priv->irq);
  irq_detach(priv->irq);

  /* Disable and reset the ADC module */
}

/****************************************************************************
 * Name: adc_rxint
 *
 * Description:
 *   Call to enable or disable RX interrupts.
 *
 * Input Parameters:
 *
 * Returned Value:
 *
 ****************************************************************************/

static void adc_rxint(FAR struct adc_dev_s *dev, bool enable)
{
  FAR struct stm32_dev_s *priv = (FAR struct stm32_dev_s *)dev->ad_priv;
  uint32_t regval;

  uint32_t adc_getreg(priv, STM32_ADC_CR1_OFFSET);
  if (enable)
    {
      /* Enable the end-of-conversion ADC interrupt */

      regval |= ADC_CR1_EOCIE;
    }
  else
    {
      /* Enable all ADC interrupts */

      regval &= ~ADC_CR1_ALLINTS;
    }
  adc_putreg(priv, STM32_ADC_CR1_OFFSET, regval);
}

/****************************************************************************
 * Name: adc_ioctl
 *
 * Description:
 *   All ioctl calls will be routed through this method.
 *
 * Input Parameters:
 *
 * Returned Value:
 *
 ****************************************************************************/

static int  adc_ioctl(FAR struct adc_dev_s *dev, int cmd, unsigned long arg)
{
  return -ENOTTY;
}

/****************************************************************************
 * Name: adc_interrupt
 *
 * Description:
 *   Common ADC interrupt handler.
 *
 * Input Parameters:
 *
 * Returned Value:
 *
 ****************************************************************************/

static void adc_interrupt(FAR struct stm32_dev_s *priv)
{
  uint32_t regval;
  unsigned char ch;  /* channel */
  int32_t value;

  regval  = adc_getreg(priv, STM32_ADC_CR1_OFFSET);
  regval &= ADC_CR1_AWDCH_MASK;
  ch      = regval;

  /* Handle the ADC interrupt */

# warning "still missing logic, value computation"
  adc_receive(priv, ch, value);
  priv->buf[ch]   = 0;
  priv->count[ch] = 0;

  return OK;      
}

/****************************************************************************
 * Name: adc12_interrupt
 *
 * Description:
 *   ADC12 interrupt handler for the STM32 F1 family.
 *
 * Input Parameters:
 *
 * Returned Value:
 *
 ****************************************************************************/

#if defined(CONFIG_STM32_STM32F10XX) && (defined(CONFIG_STM32_ADC1) || defined(CONFIG_STM32_ADC2))
static int adc12_interrupt(int irq, void *context)
{
  uint32_regval;
  uint32_t pending;

  /* Check for pending ADC1 interrupts */

#ifdef CONFIG_STM32_ADC1
  regval  = getreg32(priv, STM32_ADC1_SR);
  pending = regval & ADC_SR_ALLINTS;
  if (pending != 0)
    {
      adc_interrupt(&g_adcpriv1);
      regval &= ~pending;
      putreg32(regval, STM32_ADC1_SR);
    }
#endif

  /* Check for pending ADC2 interrupts */

#ifdef CONFIG_STM32_ADC2
  regval  = getreg32(priv, STM32_ADC2_SR);
  pending = regval & ADC_SR_ALLINTS;
  if (pending != 0)
    {
      adc_interrupt(&g_adcpriv2);
      regval &= ~pending;
      putreg32(regval, STM32_ADC2_SR);
    }
#endif
  return OK;
}
#endif

/****************************************************************************
 * Name: adc3_interrupt
 *
 * Description:
 *   ADC1/2 interrupt handler for the STM32 F1 family.
 *
 * Input Parameters:
 *
 * Returned Value:
 *
 ****************************************************************************/

#ifdef CONFIG_STM32_STM32F10XX && defined (CONFIG_STM32_ADC3)
static int adc3_interrupt(int irq, void *context)
{
  uint32_t regval;
  uint32_t pending;

  /* Check for pending ADC3 interrupts */

  regval  = getreg32(priv, STM32_ADC3_SR);
  pending = regval & ADC_SR_ALLINTS;
  if (pending != 0)
    {
      adc_interrupt(&g_adcpriv3);
      regval &= ~pending;
      putreg32(regval, STM32_ADC3_SR);
    }

  return OK;
}
#endif

/****************************************************************************
 * Name: adc123_interrupt
 *
 * Description:
 *   ADC1/2/3 interrupt handler for the STM32 F4 family.
 *
 * Input Parameters:
 *
 * Returned Value:
 *
 ****************************************************************************/

#ifdef CONFIG_STM32_STM32F40XX
static int adc123_interrupt(int irq, void *context)
{
  uint32_t regval;
  uint32_t pending;

  /* Check for pending ADC1 interrupts */

#ifdef CONFIG_STM32_ADC1
  regval  = getreg32(priv, STM32_ADC1_SR);
  pending = regval & ADC_SR_ALLINTS;
  if (pending != 0)
    {
      adc_interrupt(&g_adcpriv1);
      regval &= ~pending;
      putreg32(regval, STM32_ADC1_SR);
    }
#endif

  /* Check for pending ADC2 interrupts */

#ifdef CONFIG_STM32_ADC2
  regval = getreg32(priv, STM32_ADC2_SR);
  pending = regval & ADC_SR_ALLINTS;
  if (pending != 0)
    {
      adc_interrupt(&g_adcpriv2);
      regval &= ~pending;
      putreg32(regval, STM32_ADC2_SR);
    }
#endif

  /* Check for pending ADC3 interrupts */

#ifdef CONFIG_STM32_ADC3
  regval = getreg32(priv, STM32_ADC3_SR);
  pending = regval & ADC_SR_ALLINTS;
  if (pending != 0)
    {
      adc_interrupt(&g_adcpriv3);
      regval &= ~pending;
      putreg32(regval, STM32_ADC3_SR);
    }
#endif
  return OK;
}
#endif

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: up_adcinitialize
 *
 * Description:
 *   Initialize the adc
 *
 * Returned Value:
 *   Valid can device structure reference on succcess; a NULL on failure
 *
 ****************************************************************************/

struct adc_dev_s *up_adcinitialize(int intf)
{
# warning "Question: How do you plan to handle the ADC channels?  Can we do"
#         "  16 or 18 individual channels?  or one group?"

#ifdef CONFIG_STM32_ADC1
  if (intf == 1)
    {
      return &g_adcdev1;
    }
  else
#endif
#ifdef CONFIG_STM32_ADC2
  if (intf == 2)
    {
      return &g_adcdev2;
    }
  else
#endif
#ifdef CONFIG_STM32_ADC3
  if (intf == 3)
    {
      return &g_adcdev3;
    }
  else
#endif
    {
      return NULL;
    }
}

#endif /* CONFIG_STM32_ADC || CONFIG_STM32_ADC2 || CONFIG_STM32_ADC3 */
#endif /* CONFIG_ADC */