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
40 MODULE_AUTHOR("Rafael Ignacio Zurita <rizurita@yahoo.com>");
41 MODULE_DESCRIPTION("SuperH DAC audio driver");
42 MODULE_LICENSE("GPL");
43 MODULE_SUPPORTED_DEVICE("{{SuperH DAC audio support}}");
44
45 /* Module Parameters */
46 static int index = SNDRV_DEFAULT_IDX1;
47 static char *id = SNDRV_DEFAULT_STR1;
48 module_param(index, int, 0444);
49 MODULE_PARM_DESC(index, "Index value for SuperH DAC audio.");
50 module_param(id, charp, 0444);
51 MODULE_PARM_DESC(id, "ID string for SuperH DAC audio.");
52
53 /* main struct */
54 struct 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
dac_audio_start_timer(struct snd_sh_dac * chip)69 static 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
dac_audio_stop_timer(struct snd_sh_dac * chip)75 static void dac_audio_stop_timer(struct snd_sh_dac *chip)
76 {
77 hrtimer_cancel(&chip->hrtimer);
78 }
79
dac_audio_reset(struct snd_sh_dac * chip)80 static 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
dac_audio_set_rate(struct snd_sh_dac * chip)88 static 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
96 static 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
snd_sh_dac_pcm_open(struct snd_pcm_substream * substream)114 static 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
snd_sh_dac_pcm_close(struct snd_pcm_substream * substream)131 static 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
snd_sh_dac_pcm_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * hw_params)143 static 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
snd_sh_dac_pcm_hw_free(struct snd_pcm_substream * substream)150 static int snd_sh_dac_pcm_hw_free(struct snd_pcm_substream *substream)
151 {
152 return snd_pcm_lib_free_pages(substream);
153 }
154
snd_sh_dac_pcm_prepare(struct snd_pcm_substream * substream)155 static 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
snd_sh_dac_pcm_trigger(struct snd_pcm_substream * substream,int cmd)166 static 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
snd_sh_dac_pcm_copy(struct snd_pcm_substream * substream,int channel,snd_pcm_uframes_t pos,void __user * src,snd_pcm_uframes_t count)187 static 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
snd_sh_dac_pcm_silence(struct snd_pcm_substream * substream,int channel,snd_pcm_uframes_t pos,snd_pcm_uframes_t count)213 static 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
240 static
snd_sh_dac_pcm_pointer(struct snd_pcm_substream * substream)241 snd_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 */
250 static 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
snd_sh_dac_pcm(struct snd_sh_dac * chip,int device)264 static 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 */
snd_sh_dac_remove(struct platform_device * devptr)290 static 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 */
snd_sh_dac_free(struct snd_sh_dac * chip)297 static 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
snd_sh_dac_dev_free(struct snd_device * device)306 static 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
sh_dac_audio_timer(struct hrtimer * handle)313 static 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 */
snd_sh_dac_create(struct snd_card * card,struct platform_device * devptr,struct snd_sh_dac ** rchip)347 static 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 */
snd_sh_dac_probe(struct platform_device * devptr)393 static 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
426 probe_error:
427 snd_card_free(card);
428 return err;
429 }
430
431 /*
432 * "driver" definition
433 */
434 static 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 },
440 };
441
442 module_platform_driver(sh_dac_driver);
443