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v3.15
 
  1/*
  2 * sh_dac_audio.c - SuperH DAC audio driver for ALSA
  3 *
  4 * Copyright (c) 2009 by Rafael Ignacio Zurita <rizurita@yahoo.com>
  5 *
  6 *
  7 * Based on sh_dac_audio.c (Copyright (C) 2004, 2005 by Andriy Skulysh)
  8 *
  9 *   This program is free software; you can redistribute it and/or modify
 10 *   it under the terms of the GNU General Public License as published by
 11 *   the Free Software Foundation; either version 2 of the License, or
 12 *   (at your option) any later version.
 13 *
 14 *   This program is distributed in the hope that it will be useful,
 15 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 16 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 17 *   GNU General Public License for more details.
 18 *
 19 *   You should have received a copy of the GNU General Public License
 20 *   along with this program; if not, write to the Free Software
 21 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 22 *
 23 */
 24
 25#include <linux/hrtimer.h>
 26#include <linux/interrupt.h>
 27#include <linux/io.h>
 28#include <linux/platform_device.h>
 29#include <linux/slab.h>
 30#include <linux/module.h>
 31#include <sound/core.h>
 32#include <sound/initval.h>
 33#include <sound/pcm.h>
 34#include <sound/sh_dac_audio.h>
 35#include <asm/clock.h>
 36#include <asm/hd64461.h>
 37#include <mach/hp6xx.h>
 38#include <cpu/dac.h>
 39
 40MODULE_AUTHOR("Rafael Ignacio Zurita <rizurita@yahoo.com>");
 41MODULE_DESCRIPTION("SuperH DAC audio driver");
 42MODULE_LICENSE("GPL");
 43MODULE_SUPPORTED_DEVICE("{{SuperH DAC audio support}}");
 44
 45/* Module Parameters */
 46static int index = SNDRV_DEFAULT_IDX1;
 47static char *id = SNDRV_DEFAULT_STR1;
 48module_param(index, int, 0444);
 49MODULE_PARM_DESC(index, "Index value for SuperH DAC audio.");
 50module_param(id, charp, 0444);
 51MODULE_PARM_DESC(id, "ID string for SuperH DAC audio.");
 52
 53/* main struct */
 54struct snd_sh_dac {
 55	struct snd_card *card;
 56	struct snd_pcm_substream *substream;
 57	struct hrtimer hrtimer;
 58	ktime_t wakeups_per_second;
 59
 60	int rate;
 61	int empty;
 62	char *data_buffer, *buffer_begin, *buffer_end;
 63	int processed; /* bytes proccesed, to compare with period_size */
 64	int buffer_size;
 65	struct dac_audio_pdata *pdata;
 66};
 67
 68
 69static void dac_audio_start_timer(struct snd_sh_dac *chip)
 70{
 71	hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,
 72		      HRTIMER_MODE_REL);
 73}
 74
 75static void dac_audio_stop_timer(struct snd_sh_dac *chip)
 76{
 77	hrtimer_cancel(&chip->hrtimer);
 78}
 79
 80static void dac_audio_reset(struct snd_sh_dac *chip)
 81{
 82	dac_audio_stop_timer(chip);
 83	chip->buffer_begin = chip->buffer_end = chip->data_buffer;
 84	chip->processed = 0;
 85	chip->empty = 1;
 86}
 87
 88static void dac_audio_set_rate(struct snd_sh_dac *chip)
 89{
 90	chip->wakeups_per_second = ktime_set(0, 1000000000 / chip->rate);
 91}
 92
 93
 94/* PCM INTERFACE */
 95
 96static struct snd_pcm_hardware snd_sh_dac_pcm_hw = {
 97	.info			= (SNDRV_PCM_INFO_MMAP |
 98					SNDRV_PCM_INFO_MMAP_VALID |
 99					SNDRV_PCM_INFO_INTERLEAVED |
100					SNDRV_PCM_INFO_HALF_DUPLEX),
101	.formats		= SNDRV_PCM_FMTBIT_U8,
102	.rates			= SNDRV_PCM_RATE_8000,
103	.rate_min		= 8000,
104	.rate_max		= 8000,
105	.channels_min		= 1,
106	.channels_max		= 1,
107	.buffer_bytes_max	= (48*1024),
108	.period_bytes_min	= 1,
109	.period_bytes_max	= (48*1024),
110	.periods_min		= 1,
111	.periods_max		= 1024,
112};
113
114static int snd_sh_dac_pcm_open(struct snd_pcm_substream *substream)
115{
116	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
117	struct snd_pcm_runtime *runtime = substream->runtime;
118
119	runtime->hw = snd_sh_dac_pcm_hw;
120
121	chip->substream = substream;
122	chip->buffer_begin = chip->buffer_end = chip->data_buffer;
123	chip->processed = 0;
124	chip->empty = 1;
125
126	chip->pdata->start(chip->pdata);
127
128	return 0;
129}
130
131static int snd_sh_dac_pcm_close(struct snd_pcm_substream *substream)
132{
133	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
134
135	chip->substream = NULL;
136
137	dac_audio_stop_timer(chip);
138	chip->pdata->stop(chip->pdata);
139
140	return 0;
141}
142
143static int snd_sh_dac_pcm_hw_params(struct snd_pcm_substream *substream,
144				struct snd_pcm_hw_params *hw_params)
145{
146	return snd_pcm_lib_malloc_pages(substream,
147			params_buffer_bytes(hw_params));
148}
149
150static int snd_sh_dac_pcm_hw_free(struct snd_pcm_substream *substream)
151{
152	return snd_pcm_lib_free_pages(substream);
153}
154
155static int snd_sh_dac_pcm_prepare(struct snd_pcm_substream *substream)
156{
157	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
158	struct snd_pcm_runtime *runtime = chip->substream->runtime;
159
160	chip->buffer_size = runtime->buffer_size;
161	memset(chip->data_buffer, 0, chip->pdata->buffer_size);
162
163	return 0;
164}
165
166static int snd_sh_dac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
167{
168	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
169
170	switch (cmd) {
171	case SNDRV_PCM_TRIGGER_START:
172		dac_audio_start_timer(chip);
173		break;
174	case SNDRV_PCM_TRIGGER_STOP:
175		chip->buffer_begin = chip->buffer_end = chip->data_buffer;
176		chip->processed = 0;
177		chip->empty = 1;
178		dac_audio_stop_timer(chip);
179		break;
180	default:
181		 return -EINVAL;
182	}
183
184	return 0;
185}
186
187static int snd_sh_dac_pcm_copy(struct snd_pcm_substream *substream, int channel,
188	snd_pcm_uframes_t pos, void __user *src, snd_pcm_uframes_t count)
 
189{
190	/* channel is not used (interleaved data) */
191	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
192	struct snd_pcm_runtime *runtime = substream->runtime;
193	ssize_t b_count = frames_to_bytes(runtime , count);
194	ssize_t b_pos = frames_to_bytes(runtime , pos);
195
196	if (count < 0)
197		return -EINVAL;
 
 
 
 
 
 
198
199	if (!count)
200		return 0;
201
202	memcpy_toio(chip->data_buffer + b_pos, src, b_count);
203	chip->buffer_end = chip->data_buffer + b_pos + b_count;
 
 
 
 
 
 
 
204
205	if (chip->empty) {
206		chip->empty = 0;
207		dac_audio_start_timer(chip);
208	}
209
210	return 0;
211}
212
213static int snd_sh_dac_pcm_silence(struct snd_pcm_substream *substream,
214				  int channel, snd_pcm_uframes_t pos,
215				  snd_pcm_uframes_t count)
216{
217	/* channel is not used (interleaved data) */
218	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
219	struct snd_pcm_runtime *runtime = substream->runtime;
220	ssize_t b_count = frames_to_bytes(runtime , count);
221	ssize_t b_pos = frames_to_bytes(runtime , pos);
222
223	if (count < 0)
224		return -EINVAL;
225
226	if (!count)
227		return 0;
228
229	memset_io(chip->data_buffer + b_pos, 0, b_count);
230	chip->buffer_end = chip->data_buffer + b_pos + b_count;
231
232	if (chip->empty) {
233		chip->empty = 0;
234		dac_audio_start_timer(chip);
235	}
236
237	return 0;
238}
239
240static
241snd_pcm_uframes_t snd_sh_dac_pcm_pointer(struct snd_pcm_substream *substream)
242{
243	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
244	int pointer = chip->buffer_begin - chip->data_buffer;
245
246	return pointer;
247}
248
249/* pcm ops */
250static struct snd_pcm_ops snd_sh_dac_pcm_ops = {
251	.open		= snd_sh_dac_pcm_open,
252	.close		= snd_sh_dac_pcm_close,
253	.ioctl		= snd_pcm_lib_ioctl,
254	.hw_params	= snd_sh_dac_pcm_hw_params,
255	.hw_free	= snd_sh_dac_pcm_hw_free,
256	.prepare	= snd_sh_dac_pcm_prepare,
257	.trigger	= snd_sh_dac_pcm_trigger,
258	.pointer	= snd_sh_dac_pcm_pointer,
259	.copy		= snd_sh_dac_pcm_copy,
260	.silence	= snd_sh_dac_pcm_silence,
 
261	.mmap		= snd_pcm_lib_mmap_iomem,
262};
263
264static int snd_sh_dac_pcm(struct snd_sh_dac *chip, int device)
265{
266	int err;
267	struct snd_pcm *pcm;
268
269	/* device should be always 0 for us */
270	err = snd_pcm_new(chip->card, "SH_DAC PCM", device, 1, 0, &pcm);
271	if (err < 0)
272		return err;
273
274	pcm->private_data = chip;
275	strcpy(pcm->name, "SH_DAC PCM");
276	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_sh_dac_pcm_ops);
277
278	/* buffer size=48K */
279	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
280					  snd_dma_continuous_data(GFP_KERNEL),
281							48 * 1024,
282							48 * 1024);
283
284	return 0;
285}
286/* END OF PCM INTERFACE */
287
288
289/* driver .remove  --  destructor */
290static int snd_sh_dac_remove(struct platform_device *devptr)
291{
292	snd_card_free(platform_get_drvdata(devptr));
293	return 0;
294}
295
296/* free -- it has been defined by create */
297static int snd_sh_dac_free(struct snd_sh_dac *chip)
298{
299	/* release the data */
300	kfree(chip->data_buffer);
301	kfree(chip);
302
303	return 0;
304}
305
306static int snd_sh_dac_dev_free(struct snd_device *device)
307{
308	struct snd_sh_dac *chip = device->device_data;
309
310	return snd_sh_dac_free(chip);
311}
312
313static enum hrtimer_restart sh_dac_audio_timer(struct hrtimer *handle)
314{
315	struct snd_sh_dac *chip = container_of(handle, struct snd_sh_dac,
316					       hrtimer);
317	struct snd_pcm_runtime *runtime = chip->substream->runtime;
318	ssize_t b_ps = frames_to_bytes(runtime, runtime->period_size);
319
320	if (!chip->empty) {
321		sh_dac_output(*chip->buffer_begin, chip->pdata->channel);
322		chip->buffer_begin++;
323
324		chip->processed++;
325		if (chip->processed >= b_ps) {
326			chip->processed -= b_ps;
327			snd_pcm_period_elapsed(chip->substream);
328		}
329
330		if (chip->buffer_begin == (chip->data_buffer +
331					   chip->buffer_size - 1))
332			chip->buffer_begin = chip->data_buffer;
333
334		if (chip->buffer_begin == chip->buffer_end)
335			chip->empty = 1;
336
337	}
338
339	if (!chip->empty)
340		hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,
341			      HRTIMER_MODE_REL);
342
343	return HRTIMER_NORESTART;
344}
345
346/* create  --  chip-specific constructor for the cards components */
347static int snd_sh_dac_create(struct snd_card *card,
348			     struct platform_device *devptr,
349			     struct snd_sh_dac **rchip)
350{
351	struct snd_sh_dac *chip;
352	int err;
353
354	static struct snd_device_ops ops = {
355		   .dev_free = snd_sh_dac_dev_free,
356	};
357
358	*rchip = NULL;
359
360	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
361	if (chip == NULL)
362		return -ENOMEM;
363
364	chip->card = card;
365
366	hrtimer_init(&chip->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
367	chip->hrtimer.function = sh_dac_audio_timer;
368
369	dac_audio_reset(chip);
370	chip->rate = 8000;
371	dac_audio_set_rate(chip);
372
373	chip->pdata = devptr->dev.platform_data;
374
375	chip->data_buffer = kmalloc(chip->pdata->buffer_size, GFP_KERNEL);
376	if (chip->data_buffer == NULL) {
377		kfree(chip);
378		return -ENOMEM;
379	}
380
381	err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
382	if (err < 0) {
383		snd_sh_dac_free(chip);
384		return err;
385	}
386
387	*rchip = chip;
388
389	return 0;
390}
391
392/* driver .probe  --  constructor */
393static int snd_sh_dac_probe(struct platform_device *devptr)
394{
395	struct snd_sh_dac *chip;
396	struct snd_card *card;
397	int err;
398
399	err = snd_card_new(&devptr->dev, index, id, THIS_MODULE, 0, &card);
400	if (err < 0) {
401			snd_printk(KERN_ERR "cannot allocate the card\n");
402			return err;
403	}
404
405	err = snd_sh_dac_create(card, devptr, &chip);
406	if (err < 0)
407		goto probe_error;
408
409	err = snd_sh_dac_pcm(chip, 0);
410	if (err < 0)
411		goto probe_error;
412
413	strcpy(card->driver, "snd_sh_dac");
414	strcpy(card->shortname, "SuperH DAC audio driver");
415	printk(KERN_INFO "%s %s", card->longname, card->shortname);
416
417	err = snd_card_register(card);
418	if (err < 0)
419		goto probe_error;
420
421	snd_printk("ALSA driver for SuperH DAC audio");
422
423	platform_set_drvdata(devptr, card);
424	return 0;
425
426probe_error:
427	snd_card_free(card);
428	return err;
429}
430
431/*
432 * "driver" definition
433 */
434static struct platform_driver sh_dac_driver = {
435	.probe	= snd_sh_dac_probe,
436	.remove = snd_sh_dac_remove,
437	.driver = {
438		.name = "dac_audio",
439		.owner	= THIS_MODULE,
440	},
441};
442
443module_platform_driver(sh_dac_driver);
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * sh_dac_audio.c - SuperH DAC audio driver for ALSA
  4 *
  5 * Copyright (c) 2009 by Rafael Ignacio Zurita <rizurita@yahoo.com>
  6 *
 
  7 * Based on sh_dac_audio.c (Copyright (C) 2004, 2005 by Andriy Skulysh)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  8 */
  9
 10#include <linux/hrtimer.h>
 11#include <linux/interrupt.h>
 12#include <linux/io.h>
 13#include <linux/platform_device.h>
 14#include <linux/slab.h>
 15#include <linux/module.h>
 16#include <sound/core.h>
 17#include <sound/initval.h>
 18#include <sound/pcm.h>
 19#include <sound/sh_dac_audio.h>
 20#include <asm/clock.h>
 21#include <asm/hd64461.h>
 22#include <mach/hp6xx.h>
 23#include <cpu/dac.h>
 24
 25MODULE_AUTHOR("Rafael Ignacio Zurita <rizurita@yahoo.com>");
 26MODULE_DESCRIPTION("SuperH DAC audio driver");
 27MODULE_LICENSE("GPL");
 
 28
 29/* Module Parameters */
 30static int index = SNDRV_DEFAULT_IDX1;
 31static char *id = SNDRV_DEFAULT_STR1;
 32module_param(index, int, 0444);
 33MODULE_PARM_DESC(index, "Index value for SuperH DAC audio.");
 34module_param(id, charp, 0444);
 35MODULE_PARM_DESC(id, "ID string for SuperH DAC audio.");
 36
 37/* main struct */
 38struct snd_sh_dac {
 39	struct snd_card *card;
 40	struct snd_pcm_substream *substream;
 41	struct hrtimer hrtimer;
 42	ktime_t wakeups_per_second;
 43
 44	int rate;
 45	int empty;
 46	char *data_buffer, *buffer_begin, *buffer_end;
 47	int processed; /* bytes proccesed, to compare with period_size */
 48	int buffer_size;
 49	struct dac_audio_pdata *pdata;
 50};
 51
 52
 53static void dac_audio_start_timer(struct snd_sh_dac *chip)
 54{
 55	hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,
 56		      HRTIMER_MODE_REL);
 57}
 58
 59static void dac_audio_stop_timer(struct snd_sh_dac *chip)
 60{
 61	hrtimer_cancel(&chip->hrtimer);
 62}
 63
 64static void dac_audio_reset(struct snd_sh_dac *chip)
 65{
 66	dac_audio_stop_timer(chip);
 67	chip->buffer_begin = chip->buffer_end = chip->data_buffer;
 68	chip->processed = 0;
 69	chip->empty = 1;
 70}
 71
 72static void dac_audio_set_rate(struct snd_sh_dac *chip)
 73{
 74	chip->wakeups_per_second = 1000000000 / chip->rate;
 75}
 76
 77
 78/* PCM INTERFACE */
 79
 80static const struct snd_pcm_hardware snd_sh_dac_pcm_hw = {
 81	.info			= (SNDRV_PCM_INFO_MMAP |
 82					SNDRV_PCM_INFO_MMAP_VALID |
 83					SNDRV_PCM_INFO_INTERLEAVED |
 84					SNDRV_PCM_INFO_HALF_DUPLEX),
 85	.formats		= SNDRV_PCM_FMTBIT_U8,
 86	.rates			= SNDRV_PCM_RATE_8000,
 87	.rate_min		= 8000,
 88	.rate_max		= 8000,
 89	.channels_min		= 1,
 90	.channels_max		= 1,
 91	.buffer_bytes_max	= (48*1024),
 92	.period_bytes_min	= 1,
 93	.period_bytes_max	= (48*1024),
 94	.periods_min		= 1,
 95	.periods_max		= 1024,
 96};
 97
 98static int snd_sh_dac_pcm_open(struct snd_pcm_substream *substream)
 99{
100	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
101	struct snd_pcm_runtime *runtime = substream->runtime;
102
103	runtime->hw = snd_sh_dac_pcm_hw;
104
105	chip->substream = substream;
106	chip->buffer_begin = chip->buffer_end = chip->data_buffer;
107	chip->processed = 0;
108	chip->empty = 1;
109
110	chip->pdata->start(chip->pdata);
111
112	return 0;
113}
114
115static int snd_sh_dac_pcm_close(struct snd_pcm_substream *substream)
116{
117	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
118
119	chip->substream = NULL;
120
121	dac_audio_stop_timer(chip);
122	chip->pdata->stop(chip->pdata);
123
124	return 0;
125}
126
 
 
 
 
 
 
 
 
 
 
 
 
127static int snd_sh_dac_pcm_prepare(struct snd_pcm_substream *substream)
128{
129	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
130	struct snd_pcm_runtime *runtime = chip->substream->runtime;
131
132	chip->buffer_size = runtime->buffer_size;
133	memset(chip->data_buffer, 0, chip->pdata->buffer_size);
134
135	return 0;
136}
137
138static int snd_sh_dac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
139{
140	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
141
142	switch (cmd) {
143	case SNDRV_PCM_TRIGGER_START:
144		dac_audio_start_timer(chip);
145		break;
146	case SNDRV_PCM_TRIGGER_STOP:
147		chip->buffer_begin = chip->buffer_end = chip->data_buffer;
148		chip->processed = 0;
149		chip->empty = 1;
150		dac_audio_stop_timer(chip);
151		break;
152	default:
153		 return -EINVAL;
154	}
155
156	return 0;
157}
158
159static int snd_sh_dac_pcm_copy(struct snd_pcm_substream *substream,
160			       int channel, unsigned long pos,
161			       void __user *src, unsigned long count)
162{
163	/* channel is not used (interleaved data) */
164	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 
 
 
165
166	if (copy_from_user_toio(chip->data_buffer + pos, src, count))
167		return -EFAULT;
168	chip->buffer_end = chip->data_buffer + pos + count;
169
170	if (chip->empty) {
171		chip->empty = 0;
172		dac_audio_start_timer(chip);
173	}
174
175	return 0;
176}
177
178static int snd_sh_dac_pcm_copy_kernel(struct snd_pcm_substream *substream,
179				      int channel, unsigned long pos,
180				      void *src, unsigned long count)
181{
182	/* channel is not used (interleaved data) */
183	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
184
185	memcpy_toio(chip->data_buffer + pos, src, count);
186	chip->buffer_end = chip->data_buffer + pos + count;
187
188	if (chip->empty) {
189		chip->empty = 0;
190		dac_audio_start_timer(chip);
191	}
192
193	return 0;
194}
195
196static int snd_sh_dac_pcm_silence(struct snd_pcm_substream *substream,
197				  int channel, unsigned long pos,
198				  unsigned long count)
199{
200	/* channel is not used (interleaved data) */
201	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
 
 
 
 
 
 
 
 
 
202
203	memset_io(chip->data_buffer + pos, 0, count);
204	chip->buffer_end = chip->data_buffer + pos + count;
205
206	if (chip->empty) {
207		chip->empty = 0;
208		dac_audio_start_timer(chip);
209	}
210
211	return 0;
212}
213
214static
215snd_pcm_uframes_t snd_sh_dac_pcm_pointer(struct snd_pcm_substream *substream)
216{
217	struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
218	int pointer = chip->buffer_begin - chip->data_buffer;
219
220	return pointer;
221}
222
223/* pcm ops */
224static const struct snd_pcm_ops snd_sh_dac_pcm_ops = {
225	.open		= snd_sh_dac_pcm_open,
226	.close		= snd_sh_dac_pcm_close,
 
 
 
227	.prepare	= snd_sh_dac_pcm_prepare,
228	.trigger	= snd_sh_dac_pcm_trigger,
229	.pointer	= snd_sh_dac_pcm_pointer,
230	.copy_user	= snd_sh_dac_pcm_copy,
231	.copy_kernel	= snd_sh_dac_pcm_copy_kernel,
232	.fill_silence	= snd_sh_dac_pcm_silence,
233	.mmap		= snd_pcm_lib_mmap_iomem,
234};
235
236static int snd_sh_dac_pcm(struct snd_sh_dac *chip, int device)
237{
238	int err;
239	struct snd_pcm *pcm;
240
241	/* device should be always 0 for us */
242	err = snd_pcm_new(chip->card, "SH_DAC PCM", device, 1, 0, &pcm);
243	if (err < 0)
244		return err;
245
246	pcm->private_data = chip;
247	strcpy(pcm->name, "SH_DAC PCM");
248	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_sh_dac_pcm_ops);
249
250	/* buffer size=48K */
251	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
252				       NULL, 48 * 1024, 48 * 1024);
 
 
253
254	return 0;
255}
256/* END OF PCM INTERFACE */
257
258
259/* driver .remove  --  destructor */
260static int snd_sh_dac_remove(struct platform_device *devptr)
261{
262	snd_card_free(platform_get_drvdata(devptr));
263	return 0;
264}
265
266/* free -- it has been defined by create */
267static int snd_sh_dac_free(struct snd_sh_dac *chip)
268{
269	/* release the data */
270	kfree(chip->data_buffer);
271	kfree(chip);
272
273	return 0;
274}
275
276static int snd_sh_dac_dev_free(struct snd_device *device)
277{
278	struct snd_sh_dac *chip = device->device_data;
279
280	return snd_sh_dac_free(chip);
281}
282
283static enum hrtimer_restart sh_dac_audio_timer(struct hrtimer *handle)
284{
285	struct snd_sh_dac *chip = container_of(handle, struct snd_sh_dac,
286					       hrtimer);
287	struct snd_pcm_runtime *runtime = chip->substream->runtime;
288	ssize_t b_ps = frames_to_bytes(runtime, runtime->period_size);
289
290	if (!chip->empty) {
291		sh_dac_output(*chip->buffer_begin, chip->pdata->channel);
292		chip->buffer_begin++;
293
294		chip->processed++;
295		if (chip->processed >= b_ps) {
296			chip->processed -= b_ps;
297			snd_pcm_period_elapsed(chip->substream);
298		}
299
300		if (chip->buffer_begin == (chip->data_buffer +
301					   chip->buffer_size - 1))
302			chip->buffer_begin = chip->data_buffer;
303
304		if (chip->buffer_begin == chip->buffer_end)
305			chip->empty = 1;
306
307	}
308
309	if (!chip->empty)
310		hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,
311			      HRTIMER_MODE_REL);
312
313	return HRTIMER_NORESTART;
314}
315
316/* create  --  chip-specific constructor for the cards components */
317static int snd_sh_dac_create(struct snd_card *card,
318			     struct platform_device *devptr,
319			     struct snd_sh_dac **rchip)
320{
321	struct snd_sh_dac *chip;
322	int err;
323
324	static const struct snd_device_ops ops = {
325		   .dev_free = snd_sh_dac_dev_free,
326	};
327
328	*rchip = NULL;
329
330	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
331	if (chip == NULL)
332		return -ENOMEM;
333
334	chip->card = card;
335
336	hrtimer_init(&chip->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
337	chip->hrtimer.function = sh_dac_audio_timer;
338
339	dac_audio_reset(chip);
340	chip->rate = 8000;
341	dac_audio_set_rate(chip);
342
343	chip->pdata = devptr->dev.platform_data;
344
345	chip->data_buffer = kmalloc(chip->pdata->buffer_size, GFP_KERNEL);
346	if (chip->data_buffer == NULL) {
347		kfree(chip);
348		return -ENOMEM;
349	}
350
351	err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
352	if (err < 0) {
353		snd_sh_dac_free(chip);
354		return err;
355	}
356
357	*rchip = chip;
358
359	return 0;
360}
361
362/* driver .probe  --  constructor */
363static int snd_sh_dac_probe(struct platform_device *devptr)
364{
365	struct snd_sh_dac *chip;
366	struct snd_card *card;
367	int err;
368
369	err = snd_card_new(&devptr->dev, index, id, THIS_MODULE, 0, &card);
370	if (err < 0) {
371			snd_printk(KERN_ERR "cannot allocate the card\n");
372			return err;
373	}
374
375	err = snd_sh_dac_create(card, devptr, &chip);
376	if (err < 0)
377		goto probe_error;
378
379	err = snd_sh_dac_pcm(chip, 0);
380	if (err < 0)
381		goto probe_error;
382
383	strcpy(card->driver, "snd_sh_dac");
384	strcpy(card->shortname, "SuperH DAC audio driver");
385	printk(KERN_INFO "%s %s", card->longname, card->shortname);
386
387	err = snd_card_register(card);
388	if (err < 0)
389		goto probe_error;
390
391	snd_printk(KERN_INFO "ALSA driver for SuperH DAC audio");
392
393	platform_set_drvdata(devptr, card);
394	return 0;
395
396probe_error:
397	snd_card_free(card);
398	return err;
399}
400
401/*
402 * "driver" definition
403 */
404static struct platform_driver sh_dac_driver = {
405	.probe	= snd_sh_dac_probe,
406	.remove = snd_sh_dac_remove,
407	.driver = {
408		.name = "dac_audio",
 
409	},
410};
411
412module_platform_driver(sh_dac_driver);