text: /*******************************************************************************
   * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
   *
   * Permission is hereby granted, free of charge, to any person obtaining a
   * copy of this software and associated documentation files (the "Software"),
   * to deal in the Software without restriction, including without limitation
   * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   * and/or sell copies of the Software, and to permit persons to whom the
   * Software is furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included
   * in all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
   * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
   * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
   * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
   * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
   * OTHER DEALINGS IN THE SOFTWARE.
   *
   * Except as contained in this notice, the name of Maxim Integrated
   * Products, Inc. shall not be used except as stated in the Maxim Integrated
   * Products, Inc. Branding Policy.
   *
   * The mere transfer of this software does not imply any licenses
   * of trade secrets, proprietary technology, copyrights, patents,
   * trademarks, maskwork rights, or any other form of intellectual
   * property whatsoever. Maxim Integrated Products, Inc. retains all
   * ownership rights.
   *
   * $Date: 2016-03-11 11:46:37 -0600 (Fri, 11 Mar 2016) $
   * $Revision: 21839 $
   *
   ******************************************************************************/
  
  #include <stddef.h>
  #include "pt.h"
  
  /******************************************************************************/
  void PT_Init(sys_pt_clk_scale clk_scale)
  {
      //disable all pulse trains
      MXC_PTG->enable = 0;
  
      //clear all interrupts
      MXC_PTG->intfl = MXC_PTG->intfl;
  
      SYS_PT_Init(clk_scale);
  }
  
  /******************************************************************************/
  int PT_PTConfig(mxc_pt_regs_t *pt, pt_pt_cfg_t *cfg, const sys_cfg_pt_t *sysCfg)
  {
      int err;
      uint32_t ptClock;
      uint32_t rate;
  
      //check for valid base pointer
      MXC_ASSERT(MXC_PT_GET_IDX(pt) >= 0);
  
      if(cfg == NULL)
          return E_NULL_PTR;
  
      if(cfg->bps == 0)
          return E_BAD_PARAM;
  
      //disable pulse train
      PT_Stop(pt);
  
      //setup system GPIO configuration
      if((err = SYS_PT_Config(pt, sysCfg)) != E_NO_ERROR)
          return err;
  
      //get PT clock frequency from SYS level
      ptClock = SYS_PT_GetFreq();
  
      if(ptClock == 0)
          return E_UNINITIALIZED;
  
      if(ptClock < (cfg->bps))
          return E_BAD_STATE;
  
      rate = (ptClock / (cfg->bps));
  
      pt->rate_length = ((rate << MXC_F_PT_RATE_LENGTH_RATE_CONTROL_POS)
                         & MXC_F_PT_RATE_LENGTH_RATE_CONTROL) |
                        ((cfg->ptLength << MXC_F_PT_RATE_LENGTH_MODE_POS)
                         & MXC_F_PT_RATE_LENGTH_MODE);
  
      pt->train = cfg->pattern;
      pt->loop = ((cfg->loop << MXC_F_PT_LOOP_COUNT_POS) & MXC_F_PT_LOOP_COUNT) |
                 ((cfg->loopDelay << MXC_F_PT_LOOP_DELAY_POS) & MXC_F_PT_LOOP_DELAY);
  
      return E_NO_ERROR;
  }
  
  /******************************************************************************/
  int PT_SqrWaveConfig(mxc_pt_regs_t *pt, uint32_t freq, const sys_cfg_pt_t *sysCfg)
  {
      int err;
      uint32_t ptClock;
      uint32_t rate;
  
      //check for valid base pointer
      MXC_ASSERT(MXC_PT_GET_IDX(pt) >= 0);
  
      if(freq == 0)
          return E_BAD_PARAM;
  
      //disable pulse train
      PT_Stop(pt);
  
      //setup system GPIO configuration
      if((err = SYS_PT_Config(pt, sysCfg)) != E_NO_ERROR)
          return err;
  
      //get PT clock frequency from SYS level
      ptClock = SYS_PT_GetFreq();
  
      if(ptClock == 0)
          return E_UNINITIALIZED;
  
      if(ptClock < (2*freq))
          return E_BAD_STATE;
  
      rate = (ptClock / (2*freq)) + 1;
  
      pt->rate_length = ((rate << MXC_F_PT_RATE_LENGTH_RATE_CONTROL_POS)
                         & MXC_F_PT_RATE_LENGTH_RATE_CONTROL) |
                        (MXC_V_PT_RATE_LENGTH_MODE_SQUARE_WAVE << MXC_F_PT_RATE_LENGTH_MODE_POS);
  
      return E_NO_ERROR;
  }
  