1 /*
2 * dma.c -- ALSA Soc Audio Layer
3 *
4 * (c) 2006 Wolfson Microelectronics PLC.
5 * Graeme Gregory graeme.gregory@wolfsonmicro.com or linux@wolfsonmicro.com
6 *
7 * Copyright 2004-2005 Simtec Electronics
8 * http://armlinux.simtec.co.uk/
9 * Ben Dooks <ben@simtec.co.uk>
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the
13 * Free Software Foundation; either version 2 of the License, or (at your
14 * option) any later version.
15 */
16
17 #include <linux/slab.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/module.h>
20
21 #include <sound/soc.h>
22 #include <sound/pcm_params.h>
23
24 #include <asm/dma.h>
25 #include <mach/hardware.h>
26 #include <mach/dma.h>
27
28 #include "dma.h"
29
30 #define ST_RUNNING (1<<0)
31 #define ST_OPENED (1<<1)
32
33 static const struct snd_pcm_hardware dma_hardware = {
34 .info = SNDRV_PCM_INFO_INTERLEAVED |
35 SNDRV_PCM_INFO_BLOCK_TRANSFER |
36 SNDRV_PCM_INFO_MMAP |
37 SNDRV_PCM_INFO_MMAP_VALID,
38 .formats = SNDRV_PCM_FMTBIT_S16_LE |
39 SNDRV_PCM_FMTBIT_U16_LE |
40 SNDRV_PCM_FMTBIT_U8 |
41 SNDRV_PCM_FMTBIT_S8,
42 .channels_min = 2,
43 .channels_max = 2,
44 .buffer_bytes_max = 128*1024,
45 .period_bytes_min = PAGE_SIZE,
46 .period_bytes_max = PAGE_SIZE*2,
47 .periods_min = 2,
48 .periods_max = 128,
49 .fifo_size = 32,
50 };
51
52 struct runtime_data {
53 spinlock_t lock;
54 int state;
55 unsigned int dma_loaded;
56 unsigned int dma_period;
57 dma_addr_t dma_start;
58 dma_addr_t dma_pos;
59 dma_addr_t dma_end;
60 struct s3c_dma_params *params;
61 };
62
63 static void audio_buffdone(void *data);
64
65 /* dma_enqueue
66 *
67 * place a dma buffer onto the queue for the dma system
68 * to handle.
69 */
dma_enqueue(struct snd_pcm_substream * substream)70 static void dma_enqueue(struct snd_pcm_substream *substream)
71 {
72 struct runtime_data *prtd = substream->runtime->private_data;
73 dma_addr_t pos = prtd->dma_pos;
74 unsigned int limit;
75 struct samsung_dma_prep dma_info;
76
77 pr_debug("Entered %s\n", __func__);
78
79 limit = (prtd->dma_end - prtd->dma_start) / prtd->dma_period;
80
81 pr_debug("%s: loaded %d, limit %d\n",
82 __func__, prtd->dma_loaded, limit);
83
84 dma_info.cap = (samsung_dma_has_circular() ? DMA_CYCLIC : DMA_SLAVE);
85 dma_info.direction =
86 (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
87 ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
88 dma_info.fp = audio_buffdone;
89 dma_info.fp_param = substream;
90 dma_info.period = prtd->dma_period;
91 dma_info.len = prtd->dma_period*limit;
92
93 while (prtd->dma_loaded < limit) {
94 pr_debug("dma_loaded: %d\n", prtd->dma_loaded);
95
96 if ((pos + dma_info.period) > prtd->dma_end) {
97 dma_info.period = prtd->dma_end - pos;
98 pr_debug("%s: corrected dma len %ld\n",
99 __func__, dma_info.period);
100 }
101
102 dma_info.buf = pos;
103 prtd->params->ops->prepare(prtd->params->ch, &dma_info);
104
105 prtd->dma_loaded++;
106 pos += prtd->dma_period;
107 if (pos >= prtd->dma_end)
108 pos = prtd->dma_start;
109 }
110
111 prtd->dma_pos = pos;
112 }
113
audio_buffdone(void * data)114 static void audio_buffdone(void *data)
115 {
116 struct snd_pcm_substream *substream = data;
117 struct runtime_data *prtd = substream->runtime->private_data;
118
119 pr_debug("Entered %s\n", __func__);
120
121 if (prtd->state & ST_RUNNING) {
122 prtd->dma_pos += prtd->dma_period;
123 if (prtd->dma_pos >= prtd->dma_end)
124 prtd->dma_pos = prtd->dma_start;
125
126 if (substream)
127 snd_pcm_period_elapsed(substream);
128
129 spin_lock(&prtd->lock);
130 if (!samsung_dma_has_circular()) {
131 prtd->dma_loaded--;
132 dma_enqueue(substream);
133 }
134 spin_unlock(&prtd->lock);
135 }
136 }
137
dma_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params)138 static int dma_hw_params(struct snd_pcm_substream *substream,
139 struct snd_pcm_hw_params *params)
140 {
141 struct snd_pcm_runtime *runtime = substream->runtime;
142 struct runtime_data *prtd = runtime->private_data;
143 struct snd_soc_pcm_runtime *rtd = substream->private_data;
144 unsigned long totbytes = params_buffer_bytes(params);
145 struct s3c_dma_params *dma =
146 snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
147 struct samsung_dma_req req;
148 struct samsung_dma_config config;
149
150 pr_debug("Entered %s\n", __func__);
151
152 /* return if this is a bufferless transfer e.g.
153 * codec <--> BT codec or GSM modem -- lg FIXME */
154 if (!dma)
155 return 0;
156
157 /* this may get called several times by oss emulation
158 * with different params -HW */
159 if (prtd->params == NULL) {
160 /* prepare DMA */
161 prtd->params = dma;
162
163 pr_debug("params %p, client %p, channel %d\n", prtd->params,
164 prtd->params->client, prtd->params->channel);
165
166 prtd->params->ops = samsung_dma_get_ops();
167
168 req.cap = (samsung_dma_has_circular() ?
169 DMA_CYCLIC : DMA_SLAVE);
170 req.client = prtd->params->client;
171 config.direction =
172 (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
173 ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
174 config.width = prtd->params->dma_size;
175 config.fifo = prtd->params->dma_addr;
176 prtd->params->ch = prtd->params->ops->request(
177 prtd->params->channel, &req, rtd->cpu_dai->dev,
178 prtd->params->ch_name);
179 prtd->params->ops->config(prtd->params->ch, &config);
180 }
181
182 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
183
184 runtime->dma_bytes = totbytes;
185
186 spin_lock_irq(&prtd->lock);
187 prtd->dma_loaded = 0;
188 prtd->dma_period = params_period_bytes(params);
189 prtd->dma_start = runtime->dma_addr;
190 prtd->dma_pos = prtd->dma_start;
191 prtd->dma_end = prtd->dma_start + totbytes;
192 spin_unlock_irq(&prtd->lock);
193
194 return 0;
195 }
196
dma_hw_free(struct snd_pcm_substream * substream)197 static int dma_hw_free(struct snd_pcm_substream *substream)
198 {
199 struct runtime_data *prtd = substream->runtime->private_data;
200
201 pr_debug("Entered %s\n", __func__);
202
203 snd_pcm_set_runtime_buffer(substream, NULL);
204
205 if (prtd->params) {
206 prtd->params->ops->flush(prtd->params->ch);
207 prtd->params->ops->release(prtd->params->ch,
208 prtd->params->client);
209 prtd->params = NULL;
210 }
211
212 return 0;
213 }
214
dma_prepare(struct snd_pcm_substream * substream)215 static int dma_prepare(struct snd_pcm_substream *substream)
216 {
217 struct runtime_data *prtd = substream->runtime->private_data;
218 int ret = 0;
219
220 pr_debug("Entered %s\n", __func__);
221
222 /* return if this is a bufferless transfer e.g.
223 * codec <--> BT codec or GSM modem -- lg FIXME */
224 if (!prtd->params)
225 return 0;
226
227 /* flush the DMA channel */
228 prtd->params->ops->flush(prtd->params->ch);
229
230 prtd->dma_loaded = 0;
231 prtd->dma_pos = prtd->dma_start;
232
233 /* enqueue dma buffers */
234 dma_enqueue(substream);
235
236 return ret;
237 }
238
dma_trigger(struct snd_pcm_substream * substream,int cmd)239 static int dma_trigger(struct snd_pcm_substream *substream, int cmd)
240 {
241 struct runtime_data *prtd = substream->runtime->private_data;
242 int ret = 0;
243
244 pr_debug("Entered %s\n", __func__);
245
246 spin_lock(&prtd->lock);
247
248 switch (cmd) {
249 case SNDRV_PCM_TRIGGER_START:
250 prtd->state |= ST_RUNNING;
251 prtd->params->ops->trigger(prtd->params->ch);
252 break;
253
254 case SNDRV_PCM_TRIGGER_STOP:
255 prtd->state &= ~ST_RUNNING;
256 prtd->params->ops->stop(prtd->params->ch);
257 break;
258
259 default:
260 ret = -EINVAL;
261 break;
262 }
263
264 spin_unlock(&prtd->lock);
265
266 return ret;
267 }
268
269 static snd_pcm_uframes_t
dma_pointer(struct snd_pcm_substream * substream)270 dma_pointer(struct snd_pcm_substream *substream)
271 {
272 struct snd_pcm_runtime *runtime = substream->runtime;
273 struct runtime_data *prtd = runtime->private_data;
274 unsigned long res;
275
276 pr_debug("Entered %s\n", __func__);
277
278 res = prtd->dma_pos - prtd->dma_start;
279
280 pr_debug("Pointer offset: %lu\n", res);
281
282 /* we seem to be getting the odd error from the pcm library due
283 * to out-of-bounds pointers. this is maybe due to the dma engine
284 * not having loaded the new values for the channel before being
285 * called... (todo - fix )
286 */
287
288 if (res >= snd_pcm_lib_buffer_bytes(substream)) {
289 if (res == snd_pcm_lib_buffer_bytes(substream))
290 res = 0;
291 }
292
293 return bytes_to_frames(substream->runtime, res);
294 }
295
dma_open(struct snd_pcm_substream * substream)296 static int dma_open(struct snd_pcm_substream *substream)
297 {
298 struct snd_pcm_runtime *runtime = substream->runtime;
299 struct runtime_data *prtd;
300
301 pr_debug("Entered %s\n", __func__);
302
303 snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
304 snd_soc_set_runtime_hwparams(substream, &dma_hardware);
305
306 prtd = kzalloc(sizeof(struct runtime_data), GFP_KERNEL);
307 if (prtd == NULL)
308 return -ENOMEM;
309
310 spin_lock_init(&prtd->lock);
311
312 runtime->private_data = prtd;
313 return 0;
314 }
315
dma_close(struct snd_pcm_substream * substream)316 static int dma_close(struct snd_pcm_substream *substream)
317 {
318 struct snd_pcm_runtime *runtime = substream->runtime;
319 struct runtime_data *prtd = runtime->private_data;
320
321 pr_debug("Entered %s\n", __func__);
322
323 if (!prtd)
324 pr_debug("dma_close called with prtd == NULL\n");
325
326 kfree(prtd);
327
328 return 0;
329 }
330
dma_mmap(struct snd_pcm_substream * substream,struct vm_area_struct * vma)331 static int dma_mmap(struct snd_pcm_substream *substream,
332 struct vm_area_struct *vma)
333 {
334 struct snd_pcm_runtime *runtime = substream->runtime;
335
336 pr_debug("Entered %s\n", __func__);
337
338 return dma_mmap_writecombine(substream->pcm->card->dev, vma,
339 runtime->dma_area,
340 runtime->dma_addr,
341 runtime->dma_bytes);
342 }
343
344 static struct snd_pcm_ops dma_ops = {
345 .open = dma_open,
346 .close = dma_close,
347 .ioctl = snd_pcm_lib_ioctl,
348 .hw_params = dma_hw_params,
349 .hw_free = dma_hw_free,
350 .prepare = dma_prepare,
351 .trigger = dma_trigger,
352 .pointer = dma_pointer,
353 .mmap = dma_mmap,
354 };
355
preallocate_dma_buffer(struct snd_pcm * pcm,int stream)356 static int preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
357 {
358 struct snd_pcm_substream *substream = pcm->streams[stream].substream;
359 struct snd_dma_buffer *buf = &substream->dma_buffer;
360 size_t size = dma_hardware.buffer_bytes_max;
361
362 pr_debug("Entered %s\n", __func__);
363
364 buf->dev.type = SNDRV_DMA_TYPE_DEV;
365 buf->dev.dev = pcm->card->dev;
366 buf->private_data = NULL;
367 buf->area = dma_alloc_writecombine(pcm->card->dev, size,
368 &buf->addr, GFP_KERNEL);
369 if (!buf->area)
370 return -ENOMEM;
371 buf->bytes = size;
372 return 0;
373 }
374
dma_free_dma_buffers(struct snd_pcm * pcm)375 static void dma_free_dma_buffers(struct snd_pcm *pcm)
376 {
377 struct snd_pcm_substream *substream;
378 struct snd_dma_buffer *buf;
379 int stream;
380
381 pr_debug("Entered %s\n", __func__);
382
383 for (stream = 0; stream < 2; stream++) {
384 substream = pcm->streams[stream].substream;
385 if (!substream)
386 continue;
387
388 buf = &substream->dma_buffer;
389 if (!buf->area)
390 continue;
391
392 dma_free_writecombine(pcm->card->dev, buf->bytes,
393 buf->area, buf->addr);
394 buf->area = NULL;
395 }
396 }
397
398 static u64 dma_mask = DMA_BIT_MASK(32);
399
dma_new(struct snd_soc_pcm_runtime * rtd)400 static int dma_new(struct snd_soc_pcm_runtime *rtd)
401 {
402 struct snd_card *card = rtd->card->snd_card;
403 struct snd_pcm *pcm = rtd->pcm;
404 int ret = 0;
405
406 pr_debug("Entered %s\n", __func__);
407
408 if (!card->dev->dma_mask)
409 card->dev->dma_mask = &dma_mask;
410 if (!card->dev->coherent_dma_mask)
411 card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
412
413 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
414 ret = preallocate_dma_buffer(pcm,
415 SNDRV_PCM_STREAM_PLAYBACK);
416 if (ret)
417 goto out;
418 }
419
420 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
421 ret = preallocate_dma_buffer(pcm,
422 SNDRV_PCM_STREAM_CAPTURE);
423 if (ret)
424 goto out;
425 }
426 out:
427 return ret;
428 }
429
430 static struct snd_soc_platform_driver samsung_asoc_platform = {
431 .ops = &dma_ops,
432 .pcm_new = dma_new,
433 .pcm_free = dma_free_dma_buffers,
434 };
435
asoc_dma_platform_register(struct device * dev)436 int asoc_dma_platform_register(struct device *dev)
437 {
438 return snd_soc_register_platform(dev, &samsung_asoc_platform);
439 }
440 EXPORT_SYMBOL_GPL(asoc_dma_platform_register);
441
asoc_dma_platform_unregister(struct device * dev)442 void asoc_dma_platform_unregister(struct device *dev)
443 {
444 snd_soc_unregister_platform(dev);
445 }
446 EXPORT_SYMBOL_GPL(asoc_dma_platform_unregister);
447
448 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
449 MODULE_DESCRIPTION("Samsung ASoC DMA Driver");
450 MODULE_LICENSE("GPL");
451