/************************************************************************************ * configs/sama5d4-ek/src/sam_audio_null.c * * Copyright (C) 2014 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #include #include #include #include #include #include #include #include #include "sama5d4-ek.h" #ifdef HAVE_AUDIO_NULL /**************************************************************************** * Pre-Processor Definitions ****************************************************************************/ /**************************************************************************** * Private Types ****************************************************************************/ /**************************************************************************** * Private Function Prototypes ****************************************************************************/ /**************************************************************************** * Private Data ****************************************************************************/ /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: sam_audio_null_initialize * * Description: * Set up to use the NULL audio device for PCM unit-level testing. * * Input Parameters: * minor - The input device minor number * * Returned Value: * Zero is returned on success. Otherwise, a negated errno value is * returned to indicate the nature of the failure. * ****************************************************************************/ int sam_audio_null_initialize(int minor) { FAR struct audio_lowerhalf_s *nullaudio; FAR struct audio_lowerhalf_s *pcm; static bool initialized = false; char devname[12]; int ret; auddbg("minor %d\n", minor); DEBUGASSERT(minor >= 0 && minor <= 25); /* Have we already initialized? Since we never uninitialize we must prevent * multiple initializations. This is necessary, for example, when the * touchscreen example is used as a built-in application in NSH and can be * called numerous time. It will attempt to initialize each time. */ if (!initialized) { /* Get a null audio interface */ nullaudio = audio_null_initialize(); if (!nullaudio) { auddbg("Failed to get the NULL audio interface\n"); ret = -ENODEV; goto errout; } /* No we can embed the null audio interface into a PCM decoder * instance so that we will have a PCM front end for the NULL * audio driver. */ pcm = pcm_decode_initialize(nullaudio); if (!pcm) { auddbg("ERROR: Failed create the PCM decoder\n"); ret = -ENODEV; goto errout_with_nullaudio; } /* Create a device name */ snprintf(devname, 12, "pcm%d", minor); /* Finally, we can register the PCM/NULL audio device. */ ret = audio_register(devname, pcm); if (ret < 0) { auddbg("ERROR: Failed to register /dev/%s device: %d\n", devname, ret); goto errout_with_pcm; } /* Now we are initialized */ initialized = true; } return OK; /* Error exits. Unfortunately there is no mechanism in place now to * recover resources from most errors on initialization failures. */ errout_with_nullaudio: errout_with_pcm: errout: return ret; } #endif /* HAVE_AUDIO_NULL */