-- Minimal Ada wrapper for the Linux PWM services
-- implemented in libsimpleio.so

-- Copyright (C)2017-2023, Philip Munts dba Munts Technologies.
--
-- Redistribution and use in source and binary forms, with or without
-- modification, are permitted provided that the following conditions are met:
--
-- * Redistributions of source code must retain the above copyright notice,
--   this list of conditions and the following disclaimer.
--
-- 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 HOLDER 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.

PACKAGE libPWM IS
  PRAGMA Link_With("-lsimpleio");

  POLARITY_ACTIVELOW  : CONSTANT Integer := 0;	-- Not always allowed
  POLARITY_ACTIVEHIGH : CONSTANT Integer := 1;

  PROCEDURE Configure
   (chip     : Integer;
    channel  : Integer;
    period   : Integer;				-- nanoseconds
    ontime   : Integer;				-- nanoseconds
    polarity : Integer;
    error    : OUT Integer);
  PRAGMA Import(C, Configure, "PWM_configure");

  PROCEDURE Open
   (chip     : Integer;
    channel  : Integer;
    fd       : OUT Integer;
    error    : OUT Integer);
  PRAGMA Import(C, Open, "PWM_open");

  PROCEDURE Close
   (fd       : Integer;
    error    : OUT Integer);
  PRAGMA Import(C, Close, "PWM_close");

  PROCEDURE Write
   (fd       : Integer;
    ontime   : Integer;				-- nanoseconds
    error    : OUT Integer);
  PRAGMA Import(C, Write, "PWM_write");
END libPWM;