1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * sh_dac_audio.c - SuperH DAC audio driver for ALSA
18 #include <sound/pcm.h>
44 	int rate;  member
55 	hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,  in dac_audio_start_timer()
61 	hrtimer_cancel(&chip->hrtimer);  in dac_audio_stop_timer()
67 	chip->buffer_begin = chip->buffer_end = chip->data_buffer;  in dac_audio_reset()
68 	chip->processed = 0;  in dac_audio_reset()
69 	chip->empty = 1;  in dac_audio_reset()
74 	chip->wakeups_per_second = 1000000000 / chip->rate;  in dac_audio_set_rate()
78 /* PCM INTERFACE */
101 	struct snd_pcm_runtime *runtime = substream->runtime;  in snd_sh_dac_pcm_open()
103 	runtime->hw = snd_sh_dac_pcm_hw;  in snd_sh_dac_pcm_open()
105 	chip->substream = substream;  in snd_sh_dac_pcm_open()
106 	chip->buffer_begin = chip->buffer_end = chip->data_buffer;  in snd_sh_dac_pcm_open()
107 	chip->processed = 0;  in snd_sh_dac_pcm_open()
108 	chip->empty = 1;  in snd_sh_dac_pcm_open()
110 	chip->pdata->start(chip->pdata);  in snd_sh_dac_pcm_open()
119 	chip->substream = NULL;  in snd_sh_dac_pcm_close()
122 	chip->pdata->stop(chip->pdata);  in snd_sh_dac_pcm_close()
130 	struct snd_pcm_runtime *runtime = chip->substream->runtime;  in snd_sh_dac_pcm_prepare()
132 	chip->buffer_size = runtime->buffer_size;  in snd_sh_dac_pcm_prepare()
133 	memset(chip->data_buffer, 0, chip->pdata->buffer_size);  in snd_sh_dac_pcm_prepare()
147 		chip->buffer_begin = chip->buffer_end = chip->data_buffer;  in snd_sh_dac_pcm_trigger()
148 		chip->processed = 0;  in snd_sh_dac_pcm_trigger()
149 		chip->empty = 1;  in snd_sh_dac_pcm_trigger()
153 		 return -EINVAL;  in snd_sh_dac_pcm_trigger()
166 	if (copy_from_iter(chip->data_buffer + pos, count, src) != count)  in snd_sh_dac_pcm_copy()
167 		return -EFAULT;  in snd_sh_dac_pcm_copy()
168 	chip->buffer_end = chip->data_buffer + pos + count;  in snd_sh_dac_pcm_copy()
170 	if (chip->empty) {  in snd_sh_dac_pcm_copy()
171 		chip->empty = 0;  in snd_sh_dac_pcm_copy()
185 	memset(chip->data_buffer + pos, 0, count);  in snd_sh_dac_pcm_silence()
186 	chip->buffer_end = chip->data_buffer + pos + count;  in snd_sh_dac_pcm_silence()
188 	if (chip->empty) {  in snd_sh_dac_pcm_silence()
189 		chip->empty = 0;  in snd_sh_dac_pcm_silence()
200 	int pointer = chip->buffer_begin - chip->data_buffer;  in snd_sh_dac_pcm_pointer()
205 /* pcm ops */
219 	struct snd_pcm *pcm;  in snd_sh_dac_pcm()  local
222 	err = snd_pcm_new(chip->card, "SH_DAC PCM", device, 1, 0, &pcm);  in snd_sh_dac_pcm()
226 	pcm->private_data = chip;  in snd_sh_dac_pcm()
227 	strcpy(pcm->name, "SH_DAC PCM");  in snd_sh_dac_pcm()
228 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_sh_dac_pcm_ops);  in snd_sh_dac_pcm()
231 	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,  in snd_sh_dac_pcm()
236 /* END OF PCM INTERFACE */
239 /* driver .remove  --  destructor */
245 /* free -- it has been defined by create */
249 	kfree(chip->data_buffer);  in snd_sh_dac_free()
257 	struct snd_sh_dac *chip = device->device_data;  in snd_sh_dac_dev_free()
266 	struct snd_pcm_runtime *runtime = chip->substream->runtime;  in sh_dac_audio_timer()
267 	ssize_t b_ps = frames_to_bytes(runtime, runtime->period_size);  in sh_dac_audio_timer()
269 	if (!chip->empty) {  in sh_dac_audio_timer()
270 		sh_dac_output(*chip->buffer_begin, chip->pdata->channel);  in sh_dac_audio_timer()
271 		chip->buffer_begin++;  in sh_dac_audio_timer()
273 		chip->processed++;  in sh_dac_audio_timer()
274 		if (chip->processed >= b_ps) {  in sh_dac_audio_timer()
275 			chip->processed -= b_ps;  in sh_dac_audio_timer()
276 			snd_pcm_period_elapsed(chip->substream);  in sh_dac_audio_timer()
279 		if (chip->buffer_begin == (chip->data_buffer +  in sh_dac_audio_timer()
280 					   chip->buffer_size - 1))  in sh_dac_audio_timer()
281 			chip->buffer_begin = chip->data_buffer;  in sh_dac_audio_timer()
283 		if (chip->buffer_begin == chip->buffer_end)  in sh_dac_audio_timer()
284 			chip->empty = 1;  in sh_dac_audio_timer()
288 	if (!chip->empty)  in sh_dac_audio_timer()
289 		hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,  in sh_dac_audio_timer()
295 /* create  --  chip-specific constructor for the cards components */
311 		return -ENOMEM;  in snd_sh_dac_create()
313 	chip->card = card;  in snd_sh_dac_create()
315 	hrtimer_setup(&chip->hrtimer, sh_dac_audio_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);  in snd_sh_dac_create()
318 	chip->rate = 8000;  in snd_sh_dac_create()
321 	chip->pdata = devptr->dev.platform_data;  in snd_sh_dac_create()
323 	chip->data_buffer = kmalloc(chip->pdata->buffer_size, GFP_KERNEL);  in snd_sh_dac_create()
324 	if (chip->data_buffer == NULL) {  in snd_sh_dac_create()
326 		return -ENOMEM;  in snd_sh_dac_create()
340 /* driver .probe  --  constructor */
347 	err = snd_card_new(&devptr->dev, index, id, THIS_MODULE, 0, &card);  in snd_sh_dac_probe()
349 		dev_err(&devptr->dev, "cannot allocate the card\n");  in snd_sh_dac_probe()
361 	strcpy(card->driver, "snd_sh_dac");  in snd_sh_dac_probe()
362 	strcpy(card->shortname, "SuperH DAC audio driver");  in snd_sh_dac_probe()
363 	dev_info(&devptr->dev, "%s %s\n", card->longname, card->shortname);  in snd_sh_dac_probe()
369 	dev_info(&devptr->dev, "ALSA driver for SuperH DAC audio\n");  in snd_sh_dac_probe()