2  * SPDX-License-Identifier: BSD-2-Clause
70 	int	channels;  member
84  * Error state is indicated by value=-1 in which case application exits with
90 	if (value == -1)  in check_error()
108  * Split input buffer into channels. Input buffer is in interleaved format
109  * which means if we have 2 channels (L and R), this is what the buffer of 8
110  * samples would contain: L,R,L,R,L,R,L,R. The result are two channels
118 	for (i = 0; i < config->sample_count; ++i) {  in oss_split()
119 		channel = i % config->channels;  in oss_split()
120 		index = i / config->channels;  in oss_split()
126  * Convert channels into interleaved format and place it in output
134 	for (channel = 0; channel < config->channels; ++channel) {  in oss_merge()
135 		for (index = 0; index < config->chsamples; ++index) {  in oss_merge()
136 			output[index * config->channels + channel] =  in oss_merge()
148 	config->fd = open(config->device, O_RDWR);  in oss_init()
149 	check_error(config->fd, "open");  in oss_init()
152 	config->audio_info.dev = -1;  in oss_init()
153 	error = ioctl(config->fd, SNDCTL_ENGINEINFO, &(config->audio_info));  in oss_init()
155 	printf("min_channels: %d\n", config->audio_info.min_channels);  in oss_init()
156 	printf("max_channels: %d\n", config->audio_info.max_channels);  in oss_init()
157 	printf("latency: %d\n", config->audio_info.latency);  in oss_init()
158 	printf("handle: %s\n", config->audio_info.handle);  in oss_init()
159 	if (config->audio_info.min_rate > config->sample_rate ||  in oss_init()
160 	    config->sample_rate > config->audio_info.max_rate) {  in oss_init()
162 		    config->device, config->sample_rate);  in oss_init()
164 	if (config->channels < 1)  in oss_init()
165 		config->channels = config->audio_info.max_channels;  in oss_init()
173 	if (config->mmap) {  in oss_init()
175 		ioctl(config->fd, SNDCTL_DSP_COOKEDMODE, &tmp);  in oss_init()
179 	 * Set number of channels. If number of channels is chosen to the value  in oss_init()
182 	tmp = config->channels;  in oss_init()
183 	error = ioctl(config->fd, SNDCTL_DSP_CHANNELS, &tmp);  in oss_init()
186 	if (tmp != config->channels) {  in oss_init()
188 		    "to %d!\n", config->device, config->channels, tmp);  in oss_init()
190 	config->channels = tmp;  in oss_init()
193 	tmp = config->format;  in oss_init()
194 	error = ioctl(config->fd, SNDCTL_DSP_SETFMT, &tmp);  in oss_init()
196 	if (tmp != config->format) {  in oss_init()
198 		    config->device);  in oss_init()
202 	tmp = config->sample_rate;  in oss_init()
203 	error = ioctl(config->fd, SNDCTL_DSP_SPEED, &tmp);  in oss_init()
207 	error = ioctl(config->fd, SNDCTL_DSP_GETCAPS, &(config->audio_info.caps));  in oss_init()
209 	if (!(config->audio_info.caps & PCM_CAP_DUPLEX))  in oss_init()
212 	if (config->mmap) {  in oss_init()
213 		if (!(config->audio_info.caps & PCM_CAP_TRIGGER))  in oss_init()
215 		if (!(config->audio_info.caps & PCM_CAP_MMAP))  in oss_init()
220 	 * If desired frag is smaller than minimum, based on number of channels  in oss_init()
225 	min_frag = size2frag(config->sample_size * config->channels);  in oss_init()
227 	if (config->frag < min_frag)  in oss_init()
228 		config->frag = min_frag;  in oss_init()
234 	if (config->buffer_info.fragments < 0)  in oss_init()
235 		config->buffer_info.fragments = 2;  in oss_init()
236 	tmp = ((config->buffer_info.fragments) << 16) | config->frag;  in oss_init()
237 	error = ioctl(config->fd, SNDCTL_DSP_SETFRAGMENT, &tmp);  in oss_init()
241 	error = ioctl(config->fd, SNDCTL_DSP_GETOSPACE, &(config->buffer_info));  in oss_init()
243 	if (config->buffer_info.bytes < 1) {  in oss_init()
245 		    config->buffer_info.bytes);  in oss_init()
247 	config->sample_count = config->buffer_info.bytes / config->sample_size;  in oss_init()
248 	config->chsamples = config->sample_count / config->channels;  in oss_init()
258 		.channels = -1,  in main()
260 		.frag = -1,  in main()
263 		.buffer_info.fragments = -1,  in main()
276 	sample_t *channels = malloc(bytes);  in main()  local
292 		oss_split(&config, (sample_t *)ibuf, channels);  in main()
294 		oss_merge(&config, channels, (sample_t *)obuf);  in main()
304 	free(channels);  in main()