2 * sh_dac_audio.c - SuperH DAC audio driver for ALSA
4 * Copyright (c) 2009 by Rafael Ignacio Zurita <rizurita@yahoo.com>
7 * Based on sh_dac_audio.c (Copyright (C) 2004, 2005 by Andriy Skulysh)
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.
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.
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
25 #include <linux/hrtimer.h>
26 #include <linux/interrupt.h>
28 #include <linux/platform_device.h>
29 #include <sound/core.h>
30 #include <sound/initval.h>
31 #include <sound/pcm.h>
32 #include <sound/sh_dac_audio.h>
33 #include <asm/clock.h>
34 #include <asm/hd64461.h>
35 #include <mach/hp6xx.h>
38 MODULE_AUTHOR("Rafael Ignacio Zurita <rizurita@yahoo.com>");
39 MODULE_DESCRIPTION("SuperH DAC audio driver");
40 MODULE_LICENSE("GPL");
41 MODULE_SUPPORTED_DEVICE("{{SuperH DAC audio support}}");
43 /* Module Parameters */
44 static int index = SNDRV_DEFAULT_IDX1;
45 static char *id = SNDRV_DEFAULT_STR1;
46 module_param(index, int, 0444);
47 MODULE_PARM_DESC(index, "Index value for SuperH DAC audio.");
48 module_param(id, charp, 0444);
49 MODULE_PARM_DESC(id, "ID string for SuperH DAC audio.");
53 struct snd_card *card;
54 struct snd_pcm_substream *substream;
55 struct hrtimer hrtimer;
56 ktime_t wakeups_per_second;
60 char *data_buffer, *buffer_begin, *buffer_end;
61 int processed; /* bytes proccesed, to compare with period_size */
63 struct dac_audio_pdata *pdata;
67 static void dac_audio_start_timer(struct snd_sh_dac *chip)
69 hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,
73 static void dac_audio_stop_timer(struct snd_sh_dac *chip)
75 hrtimer_cancel(&chip->hrtimer);
78 static void dac_audio_reset(struct snd_sh_dac *chip)
80 dac_audio_stop_timer(chip);
81 chip->buffer_begin = chip->buffer_end = chip->data_buffer;
86 static void dac_audio_set_rate(struct snd_sh_dac *chip)
88 chip->wakeups_per_second = ktime_set(0, 1000000000 / chip->rate);
94 static struct snd_pcm_hardware snd_sh_dac_pcm_hw = {
95 .info = (SNDRV_PCM_INFO_MMAP |
96 SNDRV_PCM_INFO_MMAP_VALID |
97 SNDRV_PCM_INFO_INTERLEAVED |
98 SNDRV_PCM_INFO_HALF_DUPLEX),
99 .formats = SNDRV_PCM_FMTBIT_U8,
100 .rates = SNDRV_PCM_RATE_8000,
105 .buffer_bytes_max = (48*1024),
106 .period_bytes_min = 1,
107 .period_bytes_max = (48*1024),
112 static int snd_sh_dac_pcm_open(struct snd_pcm_substream *substream)
114 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
115 struct snd_pcm_runtime *runtime = substream->runtime;
117 runtime->hw = snd_sh_dac_pcm_hw;
119 chip->substream = substream;
120 chip->buffer_begin = chip->buffer_end = chip->data_buffer;
124 chip->pdata->start(chip->pdata);
129 static int snd_sh_dac_pcm_close(struct snd_pcm_substream *substream)
131 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
133 chip->substream = NULL;
135 dac_audio_stop_timer(chip);
136 chip->pdata->stop(chip->pdata);
141 static int snd_sh_dac_pcm_hw_params(struct snd_pcm_substream *substream,
142 struct snd_pcm_hw_params *hw_params)
144 return snd_pcm_lib_malloc_pages(substream,
145 params_buffer_bytes(hw_params));
148 static int snd_sh_dac_pcm_hw_free(struct snd_pcm_substream *substream)
150 return snd_pcm_lib_free_pages(substream);
153 static int snd_sh_dac_pcm_prepare(struct snd_pcm_substream *substream)
155 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
156 struct snd_pcm_runtime *runtime = chip->substream->runtime;
158 chip->buffer_size = runtime->buffer_size;
159 memset(chip->data_buffer, 0, chip->pdata->buffer_size);
164 static int snd_sh_dac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
166 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
169 case SNDRV_PCM_TRIGGER_START:
170 dac_audio_start_timer(chip);
172 case SNDRV_PCM_TRIGGER_STOP:
173 chip->buffer_begin = chip->buffer_end = chip->data_buffer;
176 dac_audio_stop_timer(chip);
185 static int snd_sh_dac_pcm_copy(struct snd_pcm_substream *substream, int channel,
186 snd_pcm_uframes_t pos, void __user *src, snd_pcm_uframes_t count)
188 /* channel is not used (interleaved data) */
189 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
190 struct snd_pcm_runtime *runtime = substream->runtime;
191 ssize_t b_count = frames_to_bytes(runtime , count);
192 ssize_t b_pos = frames_to_bytes(runtime , pos);
200 memcpy_toio(chip->data_buffer + b_pos, src, b_count);
201 chip->buffer_end = chip->data_buffer + b_pos + b_count;
205 dac_audio_start_timer(chip);
211 static int snd_sh_dac_pcm_silence(struct snd_pcm_substream *substream,
212 int channel, snd_pcm_uframes_t pos,
213 snd_pcm_uframes_t count)
215 /* channel is not used (interleaved data) */
216 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
217 struct snd_pcm_runtime *runtime = substream->runtime;
218 ssize_t b_count = frames_to_bytes(runtime , count);
219 ssize_t b_pos = frames_to_bytes(runtime , pos);
227 memset_io(chip->data_buffer + b_pos, 0, b_count);
228 chip->buffer_end = chip->data_buffer + b_pos + b_count;
232 dac_audio_start_timer(chip);
239 snd_pcm_uframes_t snd_sh_dac_pcm_pointer(struct snd_pcm_substream *substream)
241 struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
242 int pointer = chip->buffer_begin - chip->data_buffer;
248 static struct snd_pcm_ops snd_sh_dac_pcm_ops = {
249 .open = snd_sh_dac_pcm_open,
250 .close = snd_sh_dac_pcm_close,
251 .ioctl = snd_pcm_lib_ioctl,
252 .hw_params = snd_sh_dac_pcm_hw_params,
253 .hw_free = snd_sh_dac_pcm_hw_free,
254 .prepare = snd_sh_dac_pcm_prepare,
255 .trigger = snd_sh_dac_pcm_trigger,
256 .pointer = snd_sh_dac_pcm_pointer,
257 .copy = snd_sh_dac_pcm_copy,
258 .silence = snd_sh_dac_pcm_silence,
259 .mmap = snd_pcm_lib_mmap_iomem,
262 static int __devinit snd_sh_dac_pcm(struct snd_sh_dac *chip, int device)
267 /* device should be always 0 for us */
268 err = snd_pcm_new(chip->card, "SH_DAC PCM", device, 1, 0, &pcm);
272 pcm->private_data = chip;
273 strcpy(pcm->name, "SH_DAC PCM");
274 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_sh_dac_pcm_ops);
276 /* buffer size=48K */
277 snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
278 snd_dma_continuous_data(GFP_KERNEL),
284 /* END OF PCM INTERFACE */
287 /* driver .remove -- destructor */
288 static int snd_sh_dac_remove(struct platform_device *devptr)
290 snd_card_free(platform_get_drvdata(devptr));
291 platform_set_drvdata(devptr, NULL);
296 /* free -- it has been defined by create */
297 static int snd_sh_dac_free(struct snd_sh_dac *chip)
299 /* release the data */
300 kfree(chip->data_buffer);
306 static int snd_sh_dac_dev_free(struct snd_device *device)
308 struct snd_sh_dac *chip = device->device_data;
310 return snd_sh_dac_free(chip);
313 static enum hrtimer_restart sh_dac_audio_timer(struct hrtimer *handle)
315 struct snd_sh_dac *chip = container_of(handle, struct snd_sh_dac,
317 struct snd_pcm_runtime *runtime = chip->substream->runtime;
318 ssize_t b_ps = frames_to_bytes(runtime, runtime->period_size);
321 sh_dac_output(*chip->buffer_begin, chip->pdata->channel);
322 chip->buffer_begin++;
325 if (chip->processed >= b_ps) {
326 chip->processed -= b_ps;
327 snd_pcm_period_elapsed(chip->substream);
330 if (chip->buffer_begin == (chip->data_buffer +
331 chip->buffer_size - 1))
332 chip->buffer_begin = chip->data_buffer;
334 if (chip->buffer_begin == chip->buffer_end)
340 hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,
343 return HRTIMER_NORESTART;
346 /* create -- chip-specific constructor for the cards components */
347 static int __devinit snd_sh_dac_create(struct snd_card *card,
348 struct platform_device *devptr,
349 struct snd_sh_dac **rchip)
351 struct snd_sh_dac *chip;
354 static struct snd_device_ops ops = {
355 .dev_free = snd_sh_dac_dev_free,
360 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
366 hrtimer_init(&chip->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
367 chip->hrtimer.function = sh_dac_audio_timer;
369 dac_audio_reset(chip);
371 dac_audio_set_rate(chip);
373 chip->pdata = devptr->dev.platform_data;
375 chip->data_buffer = kmalloc(chip->pdata->buffer_size, GFP_KERNEL);
376 if (chip->data_buffer == NULL) {
381 err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
383 snd_sh_dac_free(chip);
392 /* driver .probe -- constructor */
393 static int __devinit snd_sh_dac_probe(struct platform_device *devptr)
395 struct snd_sh_dac *chip;
396 struct snd_card *card;
399 err = snd_card_create(index, id, THIS_MODULE, 0, &card);
401 snd_printk(KERN_ERR "cannot allocate the card\n");
405 err = snd_sh_dac_create(card, devptr, &chip);
409 err = snd_sh_dac_pcm(chip, 0);
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);
417 err = snd_card_register(card);
421 snd_printk("ALSA driver for SuperH DAC audio");
423 platform_set_drvdata(devptr, card);
432 * "driver" definition
434 static struct platform_driver driver = {
435 .probe = snd_sh_dac_probe,
436 .remove = snd_sh_dac_remove,
442 static int __init sh_dac_init(void)
444 return platform_driver_register(&driver);
447 static void __exit sh_dac_exit(void)
449 platform_driver_unregister(&driver);
452 module_init(sh_dac_init);
453 module_exit(sh_dac_exit);