/**************************************************************************** * examples/i2schar/i2schar_transmitter.c * * Copyright (C) 2013 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 "i2schar.h" #ifdef CONFIG_EXAMPLES_I2SCHAR_TX /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /**************************************************************************** * Private Types ****************************************************************************/ /**************************************************************************** * Private Function Prototypes ****************************************************************************/ /**************************************************************************** * Private Data ****************************************************************************/ /**************************************************************************** * Public Data ****************************************************************************/ /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: i2schar_transmitter() * * Description: * This is the entry point for the transmitter thread. * ****************************************************************************/ pthread_addr_t i2schar_transmitter(pthread_addr_t arg) { FAR struct ap_buffer_s *apb; struct audio_buf_desc_s desc; uint8_t crap; uint8_t *ptr; int bufsize; int nwritten; int ret; int fd; int i; int j; /* Open the I2C character device */ fd = open(g_i2schar.devpath, O_WRONLY); if (fd < 0) { int errcode = errno; message("i2schar_transmitter: ERROR: failed to open %s: %d\n", g_i2schar.devpath, errcode); pthread_exit(NULL); } /* Loop for the requested number of times */ for (i = 0, crap = 0; i < CONFIG_EXAMPLES_I2SCHAR_TXBUFFERS; i++) { /* Allocate an audio buffer of the configured size */ desc.numbytes = CONFIG_EXAMPLES_I2SCHAR_BUFSIZE; desc.u.ppBuffer = &apb; ret = apb_alloc(&desc); if (ret < 0) { message("i2schar_transmitter: ERROR: failed to allocate buffer %d: %d\n", i+1, ret); close(fd); pthread_exit(NULL); } bufsize = sizeof(struct ap_buffer_s) + CONFIG_EXAMPLES_I2SCHAR_BUFSIZE; /* Fill the audio buffer with crap */ for (j = 0, ptr = apb->samp; j < CONFIG_EXAMPLES_I2SCHAR_BUFSIZE; j++) { *ptr++ = crap++; } apb->nbytes = CONFIG_EXAMPLES_I2SCHAR_BUFSIZE; /* Then send the buffer */ do { /* Flush any output before writing */ msgflush(); /* Write the buffer to the I2S character driver */ nwritten = write(fd, apb, bufsize); if (nwritten < 0) { int errcode = errno; if (errcode != EINTR) { message("i2schar_transmitter: ERROR: write failed: %d\n", errcode); close(fd); pthread_exit(NULL); } } else if (nwritten != bufsize) { message("i2schar_transmitter: ERROR: partial write: %d\n", nwritten); close(fd); pthread_exit(NULL); } else { message("i2schar_transmitter: Send buffer %d\n", i+1); } } while (nwritten != bufsize); /* Make sure that the receiver thread has a chance to run */ pthread_yield(); } close(fd); return NULL; } #endif /* CONFIG_EXAMPLES_I2SCHAR_TX */