tinySA/os/hal/src/ext.c

/*
    ChibiOS - Copyright (C) 2006..2015 Giovanni Di Sirio

    Licensed 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.
*/

/**
 * @file    ext.c
 * @brief   EXT Driver code.
 *
 * @addtogroup EXT
 * @{
 */

#include "hal.h"

#if (HAL_USE_EXT == TRUE) || defined(__DOXYGEN__)

/*===========================================================================*/
/* Driver local definitions.                                                 */
/*===========================================================================*/

/*===========================================================================*/
/* Driver exported variables.                                                */
/*===========================================================================*/

/*===========================================================================*/
/* Driver local variables and types.                                         */
/*===========================================================================*/

/*===========================================================================*/
/* Driver local functions.                                                   */
/*===========================================================================*/

/*===========================================================================*/
/* Driver exported functions.                                                */
/*===========================================================================*/

/**
 * @brief   EXT Driver initialization.
 * @note    This function is implicitly invoked by @p halInit(), there is
 *          no need to explicitly initialize the driver.
 *
 * @init
 */
void extInit(void) {

  ext_lld_init();
}

/**
 * @brief   Initializes the standard part of a @p EXTDriver structure.
 *
 * @param[out] extp     pointer to the @p EXTDriver object
 *
 * @init
 */
void extObjectInit(EXTDriver *extp) {

  extp->state  = EXT_STOP;
  extp->config = NULL;
}

/**
 * @brief   Configures and activates the EXT peripheral.
 * @post    After activation all EXT channels are in the disabled state,
 *          use @p extChannelEnable() in order to activate them.
 *
 * @param[in] extp      pointer to the @p EXTDriver object
 * @param[in] config    pointer to the @p EXTConfig object
 *
 * @api
 */
void extStart(EXTDriver *extp, const EXTConfig *config) {

  osalDbgCheck((extp != NULL) && (config != NULL));

  osalSysLock();
  osalDbgAssert((extp->state == EXT_STOP) || (extp->state == EXT_ACTIVE),
                "invalid state");
  extp->config = config;
  ext_lld_start(extp);
  extp->state = EXT_ACTIVE;
  osalSysUnlock();
}

/**
 * @brief   Deactivates the EXT peripheral.
 *
 * @param[in] extp      pointer to the @p EXTDriver object
 *
 * @api
 */
void extStop(EXTDriver *extp) {

  osalDbgCheck(extp != NULL);

  osalSysLock();
  osalDbgAssert((extp->state == EXT_STOP) || (extp->state == EXT_ACTIVE),
                "invalid state");
  ext_lld_stop(extp);
  extp->state = EXT_STOP;
  osalSysUnlock();
}

/**
 * @brief   Enables an EXT channel.
 * @pre     The channel must not be in @p EXT_CH_MODE_DISABLED mode.
 *
 * @param[in] extp      pointer to the @p EXTDriver object
 * @param[in] channel   channel to be enabled
 *
 * @api
 */
void extChannelEnable(EXTDriver *extp, expchannel_t channel) {

  osalDbgCheck((extp != NULL) && (channel < (expchannel_t)EXT_MAX_CHANNELS));

  osalSysLock();
  osalDbgAssert((extp->state == EXT_ACTIVE) &&
                ((extp->config->channels[channel].mode &
                  EXT_CH_MODE_EDGES_MASK) != EXT_CH_MODE_DISABLED),
                "invalid state");
  extChannelEnableI(extp, channel);
  osalSysUnlock();
}

/**
 * @brief   Disables an EXT channel.
 * @pre     The channel must not be in @p EXT_CH_MODE_DISABLED mode.
 *
 * @param[in] extp      pointer to the @p EXTDriver object
 * @param[in] channel   channel to be disabled
 *
 * @api
 */
void extChannelDisable(EXTDriver *extp, expchannel_t channel) {

  osalDbgCheck((extp != NULL) && (channel < (expchannel_t)EXT_MAX_CHANNELS));

  osalSysLock();
  osalDbgAssert((extp->state == EXT_ACTIVE) &&
                ((extp->config->channels[channel].mode &
                  EXT_CH_MODE_EDGES_MASK) != EXT_CH_MODE_DISABLED),
                "invalid state");
  extChannelDisableI(extp, channel);
  osalSysUnlock();
}

/**
 * @brief   Changes the operation mode of a channel.
 * @note    This function attempts to write over the current configuration
 *          structure that must have been not declared constant. This
 *          violates the @p const qualifier in @p extStart() but it is
 *          intentional.
 * @note    This function cannot be used if the configuration structure is
 *          declared @p const.
 * @note    The effect of this function on constant configuration structures
 *          is not defined.
 *
 * @param[in] extp      pointer to the @p EXTDriver object
 * @param[in] channel   channel to be changed
 * @param[in] extcp     new configuration for the channel
 *
 * @iclass
 */
void extSetChannelModeI(EXTDriver *extp,
                        expchannel_t channel,
                        const EXTChannelConfig *extcp) {
  EXTChannelConfig *oldcp;

  osalDbgCheck((extp != NULL) &&
               (channel < (expchannel_t)EXT_MAX_CHANNELS) &&
               (extcp != NULL));

  osalDbgAssert(extp->state == EXT_ACTIVE, "invalid state");

  /* Note that here the access is enforced as non-const, known access
     violation.*/
  /*lint -save -e9005 [11.8] Known issue, the driver needs rework here.*/
  oldcp = (EXTChannelConfig *)&extp->config->channels[channel];
  /*lint -restore*/

  /* Overwriting the old channels configuration then the channel is
     reconfigured by the low level driver.*/
  *oldcp = *extcp;
  ext_lld_channel_enable(extp, channel);
}

#endif /* HAL_USE_EXT == TRUE */

/** @} */