/****************************************************************************
 * arch/arm/src/sam34/sam_gpio.c
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <stdint.h>
#include <time.h>
#include <errno.h>
#include <debug.h>

#include <nuttx/irq.h>
#include <nuttx/arch.h>
#include <arch/board/board.h>

#include "arm_internal.h"
#include "arm_arch.h"

#include "chip.h"
#include "sam_gpio.h"
#include "sam_periphclks.h"

#if defined(CONFIG_ARCH_CHIP_SAM3U) || defined(CONFIG_ARCH_CHIP_SAM3X) || \
    defined(CONFIG_ARCH_CHIP_SAM3A)
#  include "hardware/sam3u_pio.h"
#elif defined(CONFIG_ARCH_CHIP_SAM4E)
#  include "hardware/sam4e_pio.h"
#elif defined(CONFIG_ARCH_CHIP_SAM4CM) || defined(CONFIG_ARCH_CHIP_SAM4S)
#  include "hardware/sam4s_pio.h"
#else
#  error Unrecognized SAM architecture
#endif

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

#ifdef CONFIG_DEBUG_GPIO_INFO
static const char g_portchar[4]   =
{
  'A', 'B', 'C', 'D'
};
#endif

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

/****************************************************************************
 * Name: sam_gpiobase
 *
 * Description:
 *   Return the base address of the GPIO register set
 *
 ****************************************************************************/

static inline uintptr_t sam_gpiobase(gpio_pinset_t cfgset)
{
  int port = (cfgset & GPIO_PORT_MASK) >> GPIO_PORT_SHIFT;
  return SAM_PION_BASE(port);
}

/****************************************************************************
 * Name: sam_gpiopin
 *
 * Description:
 *   Return the base address of the GPIO register set
 *
 ****************************************************************************/

static inline int sam_gpiopin(gpio_pinset_t cfgset)
{
  return 1 << ((cfgset & GPIO_PIN_MASK) >> GPIO_PIN_SHIFT);
}

/****************************************************************************
 * Name: sam_gpio_enableclk
 *
 * Description:
 *   Enable clocking on the PIO port.  Port clocking is required in the
 *   following cases:
 *
 *     - In order to read values in input pins from the port
 *     - If the port supports interrupting pins
 *     - If glitch filtering is enabled
 *     - If necessary to read the input value on an open drain output (this
 *       may be done in TWI logic to detect hangs on the I2C bus).
 *     - If necessary to read the input value on peripheral pins.
 *
 ****************************************************************************/

static inline int sam_gpio_enableclk(gpio_pinset_t cfgset)
{
  /* Enable the peripheral clock for the GPIO's port controller. */

  switch (cfgset & GPIO_PORT_MASK)
    {
      case GPIO_PORT_PIOA:
        sam_pioa_enableclk();
        break;

      case GPIO_PORT_PIOB:
        sam_piob_enableclk();
        break;

#ifdef GPIO_PORT_PIOC
      case GPIO_PORT_PIOC:
        sam_pioc_enableclk();
        break;
#endif

#ifdef GPIO_PORT_PIOD
      case GPIO_PORT_PIOD:
        sam_piod_enableclk();
        break;
#endif

#ifdef GPIO_PORT_PIOE
      case GPIO_PORT_PIOE:
        sam_pioe_enableclk();
        break;
#endif

#ifdef GPIO_PORT_PIOF
      case GPIO_PORT_PIOF:
        sam_piof_enableclk();
        break;
#endif

      default:
        return -EINVAL;
    }

  return OK;
}

/****************************************************************************
 * Name: sam_configinput
 *
 * Description:
 *   Configure a GPIO input pin based on bit-encoded description of the pin.
 *
 ****************************************************************************/

static inline int sam_configinput(uintptr_t base, uint32_t pin,
                                  gpio_pinset_t cfgset)
{
#ifdef GPIO_HAVE_SCHMITT
  uint32_t regval;
#endif

  /* Disable interrupts on the pin */

  putreg32(pin, base + SAM_PIO_IDR_OFFSET);

  /* Enable/disable the pull-up as requested */

  if ((cfgset & GPIO_CFG_PULLUP) != 0)
    {
#ifdef GPIO_HAVE_PULLDOWN
      /* The pull-up on a pin can not be enabled if its pull-down is still
       * active. Therefore, we need to disable the pull-down first before
       * enabling the pull-up.
       */

      putreg32(pin, base + SAM_PIO_PPDDR_OFFSET);
#endif
      putreg32(pin, base + SAM_PIO_PUER_OFFSET);
    }
  else
    {
      putreg32(pin, base + SAM_PIO_PUDR_OFFSET);
    }

#ifdef GPIO_HAVE_PULLDOWN
  /* Enable/disable the pull-down as requested */

  if ((cfgset & GPIO_CFG_PULLDOWN) != 0)
    {
      /* The pull-down on a pin can not be enabled if its pull-up is still
       * active. Therefore, we need to disable the pull-up first before
       * enabling the pull-down.
       */

      putreg32(pin, base + SAM_PIO_PUDR_OFFSET);
      putreg32(pin, base + SAM_PIO_PPDER_OFFSET);
    }
  else
    {
      putreg32(pin, base + SAM_PIO_PPDDR_OFFSET);
    }
#endif

  /* Check if filtering should be enabled */

  if ((cfgset & GPIO_CFG_DEGLITCH) != 0)
    {
      putreg32(pin, base + SAM_PIO_IFER_OFFSET);
    }
  else
    {
      putreg32(pin, base + SAM_PIO_IFDR_OFFSET);
    }

#ifdef GPIO_HAVE_SCHMITT
  /* Enable/disable the Schmitt trigger */

  regval = getreg32(base + SAM_PIO_SCHMITT_OFFSET);
  if ((cfgset & GPIO_CFG_PULLDOWN) != 0)
    {
      regval |= pin;
    }
  else
    {
      regval &= ~pin;
    }

  putreg32(regval, base + SAM_PIO_SCHMITT_OFFSET);
#endif

  /* Configure the pin as an input and enable the GPIO function */

  putreg32(pin, base + SAM_PIO_ODR_OFFSET);
  putreg32(pin, base + SAM_PIO_PER_OFFSET);

  /* To-Do:  If DEGLITCH is selected, need to configure DIFSR, SCIFSR, and
   *         IFDGSR registers.  This would probably best be done with
   *         another, new API... perhaps sam_configfilter()
   */

  /* Enable the peripheral clock for the GPIO's port controller.
   * A GPIO input value is only sampled if the peripheral clock for its
   * controller is enabled.
   */

  return sam_gpio_enableclk(cfgset);
}

/****************************************************************************
 * Name: sam_configoutput
 *
 * Description:
 *   Configure a GPIO output pin based on bit-encoded description of the pin.
 *
 ****************************************************************************/

static inline int sam_configoutput(uintptr_t base, uint32_t pin,
                                   gpio_pinset_t cfgset)
{
  /* Disable interrupts on the pin */

  putreg32(pin, base + SAM_PIO_IDR_OFFSET);

  /* Enable/disable the pull-up as requested */

  if ((cfgset & GPIO_CFG_PULLUP) != 0)
    {
#ifdef GPIO_HAVE_PULLDOWN
      /* The pull-up on a pin can not be enabled if its pull-down is still
       * active. Therefore, we need to disable the pull-down first before
       * enabling the pull-up.
       */

      putreg32(pin, base + SAM_PIO_PPDDR_OFFSET);
#endif
      putreg32(pin, base + SAM_PIO_PUER_OFFSET);
    }
  else
    {
      putreg32(pin, base + SAM_PIO_PUDR_OFFSET);
    }

#ifdef GPIO_HAVE_PULLDOWN
  /* Enable/disable the pull-down as requested */

  if ((cfgset & GPIO_CFG_PULLDOWN) != 0)
    {
      /* The pull-down on a pin can not be enabled if its pull-up is still
       * active. Therefore, we need to disable the pull-up first before
       * enabling the pull-down.
       */

      putreg32(pin, base + SAM_PIO_PUDR_OFFSET);
      putreg32(pin, base + SAM_PIO_PPDER_OFFSET);
    }
  else
    {
      putreg32(pin, base + SAM_PIO_PPDDR_OFFSET);
    }
#endif

  /* Enable the open drain driver if requested */

  if ((cfgset & GPIO_CFG_OPENDRAIN) != 0)
    {
      putreg32(pin, base + SAM_PIO_MDER_OFFSET);
    }
  else
    {
      putreg32(pin, base + SAM_PIO_MDDR_OFFSET);
    }

  /* Set default value */

  if ((cfgset & GPIO_OUTPUT_SET) != 0)
    {
      putreg32(pin, base + SAM_PIO_SODR_OFFSET);
    }
  else
    {
      putreg32(pin, base + SAM_PIO_CODR_OFFSET);
    }

  /* Configure the pin as an output and enable the GPIO function */

  putreg32(pin, base + SAM_PIO_OER_OFFSET);
  putreg32(pin, base + SAM_PIO_PER_OFFSET);
  return OK;
}

/****************************************************************************
 * Name: sam_configperiph
 *
 * Description:
 *   Configure a GPIO pin driven by a peripheral A or B signal based on
 *   bit-encoded description of the pin.
 *
 ****************************************************************************/

static inline int sam_configperiph(uintptr_t base, uint32_t pin,
                                   gpio_pinset_t cfgset)
{
  uint32_t regval;

  /* Disable interrupts on the pin */

  putreg32(pin, base + SAM_PIO_IDR_OFFSET);

  /* Enable/disable the pull-up as requested */

  if ((cfgset & GPIO_CFG_PULLUP) != 0)
    {
#ifdef GPIO_HAVE_PULLDOWN
      /* The pull-up on a pin can not be enabled if its pull-down is still
       * active. Therefore, we need to disable the pull-down first before
       * enabling the pull-up.
       */

      putreg32(pin, base + SAM_PIO_PPDDR_OFFSET);
#endif
      putreg32(pin, base + SAM_PIO_PUER_OFFSET);
    }
  else
    {
      putreg32(pin, base + SAM_PIO_PUDR_OFFSET);
    }

#ifdef GPIO_HAVE_PULLDOWN
  /* Enable/disable the pull-down as requested */

  if ((cfgset & GPIO_CFG_PULLDOWN) != 0)
    {
      /* The pull-down on a pin can not be enabled if its pull-up is still
       * active. Therefore, we need to disable the pull-up first before
       * enabling the pull-down.
       */

      putreg32(pin, base + SAM_PIO_PUDR_OFFSET);
      putreg32(pin, base + SAM_PIO_PPDER_OFFSET);
    }
  else
    {
      putreg32(pin, base + SAM_PIO_PPDDR_OFFSET);
    }
#endif

#ifdef GPIO_HAVE_PERIPHCD
  /* Configure pin, depending upon the peripheral A, B, C or D
   *
   *   PERIPHA: ABCDSR1[n] = 0 ABCDSR2[n] = 0
   *   PERIPHB: ABCDSR1[n] = 1 ABCDSR2[n] = 0
   *   PERIPHC: ABCDSR1[n] = 0 ABCDSR2[n] = 1
   *   PERIPHD: ABCDSR1[n] = 1 ABCDSR2[n] = 1
   */

  regval = getreg32(base + SAM_PIO_ABCDSR1_OFFSET);
  if ((cfgset & GPIO_MODE_MASK) == GPIO_PERIPHA ||
      (cfgset & GPIO_MODE_MASK) == GPIO_PERIPHC)
    {
      regval &= ~pin;
    }
  else
    {
      regval |= pin;
    }

  putreg32(regval, base + SAM_PIO_ABCDSR1_OFFSET);

  regval = getreg32(base + SAM_PIO_ABCDSR2_OFFSET);
  if ((cfgset & GPIO_MODE_MASK) == GPIO_PERIPHA ||
      (cfgset & GPIO_MODE_MASK) == GPIO_PERIPHB)
    {
      regval &= ~pin;
    }
  else
    {
      regval |= pin;
    }

  putreg32(regval, base + SAM_PIO_ABCDSR2_OFFSET);

#else
  /* Configure pin, depending upon the peripheral A or B:
   *
   *   PERIPHA: ABSR[n] = 0
   *   PERIPHB: ABSR[n] = 1
   */

  regval = getreg32(base + SAM_PIO_ABSR_OFFSET);
  if ((cfgset & GPIO_MODE_MASK) == GPIO_PERIPHA)
    {
      regval &= ~pin;
    }
  else
    {
      regval |= pin;
    }

  putreg32(regval, base + SAM_PIO_ABSR_OFFSET);
#endif

  /* Disable PIO functionality */

  putreg32(pin, base + SAM_PIO_PDR_OFFSET);
  return OK;
}

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

/****************************************************************************
 * Name: sam_configgpio
 *
 * Description:
 *   Configure a GPIO pin based on bit-encoded description of the pin.
 *
 ****************************************************************************/

int sam_configgpio(gpio_pinset_t cfgset)
{
  uintptr_t base = sam_gpiobase(cfgset);
  uint32_t pin   = sam_gpiopin(cfgset);
  irqstate_t flags;
  int ret;

  /* Disable interrupts to prohibit re-entrance. */

  flags = enter_critical_section();

  /* Enable writing to GPIO registers */

  putreg32(PIO_WPMR_WPKEY, base + SAM_PIO_WPMR_OFFSET);

  /* Handle the pin configuration according to pin type */

  switch (cfgset & GPIO_MODE_MASK)
    {
      case GPIO_INPUT:
        ret = sam_configinput(base, pin, cfgset);
        break;

      case GPIO_OUTPUT:
        ret = sam_configoutput(base, pin, cfgset);
        break;

      case GPIO_PERIPHA:
      case GPIO_PERIPHB:
#ifdef GPIO_HAVE_PERIPHCD
      case GPIO_PERIPHC:
      case GPIO_PERIPHD:
#endif
        ret = sam_configperiph(base, pin, cfgset);
        break;

      default:
        ret = -EINVAL;
        break;
    }

  /* Disable writing to GPIO registers */

  putreg32(PIO_WPMR_WPEN | PIO_WPMR_WPKEY, base + SAM_PIO_WPMR_OFFSET);
  leave_critical_section(flags);

  return ret;
}

/****************************************************************************
 * Name: sam_gpiowrite
 *
 * Description:
 *   Write one or zero to the selected GPIO pin
 *
 ****************************************************************************/

void sam_gpiowrite(gpio_pinset_t pinset, bool value)
{
  uintptr_t base = sam_gpiobase(pinset);
  uint32_t  pin  = sam_gpiopin(pinset);

  if (value)
    {
      putreg32(pin, base + SAM_PIO_SODR_OFFSET);
    }
  else
    {
      putreg32(pin, base + SAM_PIO_CODR_OFFSET);
    }
}

/****************************************************************************
 * Name: sam_gpioread
 *
 * Description:
 *   Read one or zero from the selected GPIO pin
 *
 ****************************************************************************/

bool sam_gpioread(gpio_pinset_t pinset)
{
  uintptr_t base = sam_gpiobase(pinset);
  uint32_t  pin  = sam_gpiopin(pinset);
  uint32_t  regval;

  if ((pinset & GPIO_MODE_MASK) == GPIO_OUTPUT)
    {
      regval = getreg32(base + SAM_PIO_ODSR_OFFSET);
    }
  else
    {
      regval = getreg32(base + SAM_PIO_PDSR_OFFSET);
    }

  return (regval & pin) != 0;
}

/****************************************************************************
 * Function:  sam_dumpgpio
 *
 * Description:
 *   Dump all GPIO registers associated with the base address of the provided
 *   pinset.
 *
 ****************************************************************************/

#ifdef CONFIG_DEBUG_GPIO_INFO
int sam_dumpgpio(uint32_t pinset, const char *msg)
{
  irqstate_t    flags;
  uintptr_t     base;
  unsigned int  port;

  /* Get the base address associated with the PIO port */

  port = (pinset & GPIO_PORT_MASK) >> GPIO_PORT_SHIFT;
  base = SAM_PION_BASE(port);

  /* The following requires exclusive access to the GPIO registers */

  flags = enter_critical_section();

  gpioinfo("PIO%c pinset: %08x base: %08x -- %s\n",
        g_portchar[port], pinset, base, msg);
  gpioinfo("    PSR: %08x    OSR: %08x   IFSR: %08x   ODSR: %08x\n",
           getreg32(base + SAM_PIO_PSR_OFFSET),
           getreg32(base + SAM_PIO_OSR_OFFSET),
           getreg32(base + SAM_PIO_IFSR_OFFSET),
           getreg32(base + SAM_PIO_ODSR_OFFSET));
  gpioinfo("   PDSR: %08x    IMR: %08x    ISR: %08x   MDSR: %08x\n",
           getreg32(base + SAM_PIO_PDSR_OFFSET),
           getreg32(base + SAM_PIO_IMR_OFFSET),
           getreg32(base + SAM_PIO_ISR_OFFSET),
           getreg32(base + SAM_PIO_MDSR_OFFSET));
#if defined(CONFIG_ARCH_CHIP_SAM3U)
  gpioinfo("   ABSR: %08x SCIFSR: %08x  DIFSR: %08x IFDGSR: %08x\n",
           getreg32(base + SAM_PIO_ABSR_OFFSET),
           getreg32(base + SAM_PIO_SCIFSR_OFFSET),
           getreg32(base + SAM_PIO_DIFSR_OFFSET),
           getreg32(base + SAM_PIO_IFDGSR_OFFSET));
#elif defined(CONFIG_ARCH_CHIP_SAM4S) || defined(CONFIG_ARCH_CHIP_SAM4E)
  gpioinfo(" ABCDSR: %08x %08x         IFSCSR: %08x  PPDSR: %08x\n",
           getreg32(base + SAM_PIO_ABCDSR1_OFFSET),
           getreg32(base + SAM_PIO_ABCDSR2_OFFSET),
           getreg32(base + SAM_PIO_IFSCSR_OFFSET),
           getreg32(base + SAM_PIO_PPDSR_OFFSET));
#endif
  gpioinfo("   PUSR: %08x   SCDR: %08x   OWSR: %08x  AIMMR: %08x\n",
           getreg32(base + SAM_PIO_PUSR_OFFSET),
           getreg32(base + SAM_PIO_SCDR_OFFSET),
           getreg32(base + SAM_PIO_OWSR_OFFSET),
           getreg32(base + SAM_PIO_AIMMR_OFFSET));
  gpioinfo("    ESR: %08x    LSR: %08x   ELSR: %08x FELLSR: %08x\n",
           getreg32(base + SAM_PIO_ESR_OFFSET),
           getreg32(base + SAM_PIO_LSR_OFFSET),
           getreg32(base + SAM_PIO_ELSR_OFFSET),
           getreg32(base + SAM_PIO_FELLSR_OFFSET));
  gpioinfo(" FRLHSR: %08x LOCKSR: %08x   WPMR: %08x   WPSR: %08x\n",
           getreg32(base + SAM_PIO_FRLHSR_OFFSET),
           getreg32(base + SAM_PIO_LOCKSR_OFFSET),
           getreg32(base + SAM_PIO_WPMR_OFFSET),
           getreg32(base + SAM_PIO_WPSR_OFFSET));
#if defined(CONFIG_ARCH_CHIP_SAM4S) || defined(CONFIG_ARCH_CHIP_SAM4E)
  gpioinfo("   PCMR: %08x  PCIMR: %08x  PCISR: %08x   PCRHR: %08x\n",
           getreg32(base + SAM_PIO_PCMR_OFFSET),
           getreg32(base + SAM_PIO_PCIMR_OFFSET),
           getreg32(base + SAM_PIO_PCISR_OFFSET),
           getreg32(base + SAM_PIO_PCRHR_OFFSET));
#ifdef CONFIG_ARCH_CHIP_SAM4E
  gpioinfo("SCHMITT: %08x DELAYR:%08x\n",
           getreg32(base + SAM_PIO_SCHMITT_OFFSET),
           getreg32(base + SAM_PIO_DELAYR_OFFSET));
#else
  gpioinfo("SCHMITT: %08x\n",
           getreg32(base + SAM_PIO_SCHMITT_OFFSET));
#endif
#endif

  leave_critical_section(flags);
  return OK;
}
#endif