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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
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
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;
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
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
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
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
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
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
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
251 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
252 NULL, 48 * 1024, 48 * 1024);
253
254 return 0;
255}
256
257
258
259
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
267static int snd_sh_dac_free(struct snd_sh_dac *chip)
268{
269
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
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
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
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);
413
