1// SPDX-License-Identifier: GPL-2.0
2// Copyright (C) 2019 Spreadtrum Communications Inc.
3
4#include <linux/dma-mapping.h>
5#include <linux/dmaengine.h>
6#include <linux/dma/sprd-dma.h>
7#include <linux/kernel.h>
8#include <linux/module.h>
9#include <linux/of_reserved_mem.h>
10#include <linux/platform_device.h>
11#include <sound/pcm.h>
12#include <sound/pcm_params.h>
13#include <sound/soc.h>
14
15#include "sprd-pcm-dma.h"
16
17#define SPRD_PCM_DMA_LINKLIST_SIZE 64
18#define SPRD_PCM_DMA_BRUST_LEN 640
19
20struct sprd_pcm_dma_data {
21 struct dma_chan *chan;
22 struct dma_async_tx_descriptor *desc;
23 dma_cookie_t cookie;
24 dma_addr_t phys;
25 void *virt;
26 int pre_pointer;
27};
28
29struct sprd_pcm_dma_private {
30 struct snd_pcm_substream *substream;
31 struct sprd_pcm_dma_params *params;
32 struct sprd_pcm_dma_data data[SPRD_PCM_CHANNEL_MAX];
33 int hw_chan;
34 int dma_addr_offset;
35};
36
37static const struct snd_pcm_hardware sprd_pcm_hardware = {
38 .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
39 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_PAUSE |
40 SNDRV_PCM_INFO_RESUME | SNDRV_PCM_INFO_NO_PERIOD_WAKEUP,
41 .formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE,
42 .period_bytes_min = 1,
43 .period_bytes_max = 64 * 1024,
44 .periods_min = 1,
45 .periods_max = PAGE_SIZE / SPRD_PCM_DMA_LINKLIST_SIZE,
46 .buffer_bytes_max = 64 * 1024,
47};
48
49static int sprd_pcm_open(struct snd_soc_component *component,
50 struct snd_pcm_substream *substream)
51{
52 struct snd_pcm_runtime *runtime = substream->runtime;
53 struct device *dev = component->dev;
54 struct sprd_pcm_dma_private *dma_private;
55 int hw_chan = SPRD_PCM_CHANNEL_MAX;
56 int size, ret, i;
57
58 snd_soc_set_runtime_hwparams(substream, hw: &sprd_pcm_hardware);
59
60 ret = snd_pcm_hw_constraint_step(runtime, cond: 0,
61 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
62 SPRD_PCM_DMA_BRUST_LEN);
63 if (ret < 0)
64 return ret;
65
66 ret = snd_pcm_hw_constraint_step(runtime, cond: 0,
67 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
68 SPRD_PCM_DMA_BRUST_LEN);
69 if (ret < 0)
70 return ret;
71
72 ret = snd_pcm_hw_constraint_integer(runtime,
73 SNDRV_PCM_HW_PARAM_PERIODS);
74 if (ret < 0)
75 return ret;
76
77 dma_private = devm_kzalloc(dev, size: sizeof(*dma_private), GFP_KERNEL);
78 if (!dma_private)
79 return -ENOMEM;
80
81 size = runtime->hw.periods_max * SPRD_PCM_DMA_LINKLIST_SIZE;
82
83 for (i = 0; i < hw_chan; i++) {
84 struct sprd_pcm_dma_data *data = &dma_private->data[i];
85
86 data->virt = dmam_alloc_coherent(dev, size, dma_handle: &data->phys,
87 GFP_KERNEL);
88 if (!data->virt) {
89 ret = -ENOMEM;
90 goto error;
91 }
92 }
93
94 dma_private->hw_chan = hw_chan;
95 runtime->private_data = dma_private;
96 dma_private->substream = substream;
97
98 return 0;
99
100error:
101 for (i = 0; i < hw_chan; i++) {
102 struct sprd_pcm_dma_data *data = &dma_private->data[i];
103
104 if (data->virt)
105 dmam_free_coherent(dev, size, vaddr: data->virt, dma_handle: data->phys);
106 }
107
108 devm_kfree(dev, p: dma_private);
109 return ret;
110}
111
112static int sprd_pcm_close(struct snd_soc_component *component,
113 struct snd_pcm_substream *substream)
114{
115 struct snd_pcm_runtime *runtime = substream->runtime;
116 struct sprd_pcm_dma_private *dma_private = runtime->private_data;
117 struct device *dev = component->dev;
118 int size = runtime->hw.periods_max * SPRD_PCM_DMA_LINKLIST_SIZE;
119 int i;
120
121 for (i = 0; i < dma_private->hw_chan; i++) {
122 struct sprd_pcm_dma_data *data = &dma_private->data[i];
123
124 dmam_free_coherent(dev, size, vaddr: data->virt, dma_handle: data->phys);
125 }
126
127 devm_kfree(dev, p: dma_private);
128
129 return 0;
130}
131
132static void sprd_pcm_dma_complete(void *data)
133{
134 struct sprd_pcm_dma_private *dma_private = data;
135 struct snd_pcm_substream *substream = dma_private->substream;
136
137 snd_pcm_period_elapsed(substream);
138}
139
140static void sprd_pcm_release_dma_channel(struct snd_pcm_substream *substream)
141{
142 struct snd_pcm_runtime *runtime = substream->runtime;
143 struct sprd_pcm_dma_private *dma_private = runtime->private_data;
144 int i;
145
146 for (i = 0; i < SPRD_PCM_CHANNEL_MAX; i++) {
147 struct sprd_pcm_dma_data *data = &dma_private->data[i];
148
149 if (data->chan) {
150 dma_release_channel(chan: data->chan);
151 data->chan = NULL;
152 }
153 }
154}
155
156static int sprd_pcm_request_dma_channel(struct snd_soc_component *component,
157 struct snd_pcm_substream *substream,
158 int channels)
159{
160 struct snd_pcm_runtime *runtime = substream->runtime;
161 struct sprd_pcm_dma_private *dma_private = runtime->private_data;
162 struct device *dev = component->dev;
163 struct sprd_pcm_dma_params *dma_params = dma_private->params;
164 int i;
165
166 if (channels > SPRD_PCM_CHANNEL_MAX) {
167 dev_err(dev, "invalid dma channel number:%d\n", channels);
168 return -EINVAL;
169 }
170
171 for (i = 0; i < channels; i++) {
172 struct sprd_pcm_dma_data *data = &dma_private->data[i];
173
174 data->chan = dma_request_slave_channel(dev,
175 name: dma_params->chan_name[i]);
176 if (!data->chan) {
177 dev_err(dev, "failed to request dma channel:%s\n",
178 dma_params->chan_name[i]);
179 sprd_pcm_release_dma_channel(substream);
180 return -ENODEV;
181 }
182 }
183
184 return 0;
185}
186
187static int sprd_pcm_hw_params(struct snd_soc_component *component,
188 struct snd_pcm_substream *substream,
189 struct snd_pcm_hw_params *params)
190{
191 struct snd_pcm_runtime *runtime = substream->runtime;
192 struct sprd_pcm_dma_private *dma_private = runtime->private_data;
193 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
194 struct sprd_pcm_dma_params *dma_params;
195 size_t totsize = params_buffer_bytes(p: params);
196 size_t period = params_period_bytes(p: params);
197 int channels = params_channels(p: params);
198 int is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
199 struct scatterlist *sg;
200 unsigned long flags;
201 int ret, i, j, sg_num;
202
203 dma_params = snd_soc_dai_get_dma_data(snd_soc_rtd_to_cpu(rtd, 0), substream);
204 if (!dma_params) {
205 dev_warn(component->dev, "no dma parameters setting\n");
206 dma_private->params = NULL;
207 return 0;
208 }
209
210 if (!dma_private->params) {
211 dma_private->params = dma_params;
212 ret = sprd_pcm_request_dma_channel(component,
213 substream, channels);
214 if (ret)
215 return ret;
216 }
217
218 sg_num = totsize / period;
219 dma_private->dma_addr_offset = totsize / channels;
220
221 sg = devm_kcalloc(dev: component->dev, n: sg_num, size: sizeof(*sg), GFP_KERNEL);
222 if (!sg) {
223 ret = -ENOMEM;
224 goto sg_err;
225 }
226
227 for (i = 0; i < channels; i++) {
228 struct sprd_pcm_dma_data *data = &dma_private->data[i];
229 struct dma_chan *chan = data->chan;
230 struct dma_slave_config config = { };
231 struct sprd_dma_linklist link = { };
232 enum dma_transfer_direction dir;
233 struct scatterlist *sgt = sg;
234
235 config.src_maxburst = dma_params->fragment_len[i];
236 config.src_addr_width = dma_params->datawidth[i];
237 config.dst_addr_width = dma_params->datawidth[i];
238 if (is_playback) {
239 config.src_addr = runtime->dma_addr +
240 i * dma_private->dma_addr_offset;
241 config.dst_addr = dma_params->dev_phys[i];
242 dir = DMA_MEM_TO_DEV;
243 } else {
244 config.src_addr = dma_params->dev_phys[i];
245 config.dst_addr = runtime->dma_addr +
246 i * dma_private->dma_addr_offset;
247 dir = DMA_DEV_TO_MEM;
248 }
249
250 sg_init_table(sgt, sg_num);
251 for (j = 0; j < sg_num; j++, sgt++) {
252 u32 sg_len = period / channels;
253
254 sg_dma_len(sgt) = sg_len;
255 sg_dma_address(sgt) = runtime->dma_addr +
256 i * dma_private->dma_addr_offset + sg_len * j;
257 }
258
259 /*
260 * Configure the link-list address for the DMA engine link-list
261 * mode.
262 */
263 link.virt_addr = (unsigned long)data->virt;
264 link.phy_addr = data->phys;
265
266 ret = dmaengine_slave_config(chan, config: &config);
267 if (ret) {
268 dev_err(component->dev,
269 "failed to set slave configuration: %d\n", ret);
270 goto config_err;
271 }
272
273 /*
274 * We configure the DMA request mode, interrupt mode, channel
275 * mode and channel trigger mode by the flags.
276 */
277 flags = SPRD_DMA_FLAGS(SPRD_DMA_CHN_MODE_NONE, SPRD_DMA_NO_TRG,
278 SPRD_DMA_FRAG_REQ, SPRD_DMA_TRANS_INT);
279 data->desc = chan->device->device_prep_slave_sg(chan, sg,
280 sg_num, dir,
281 flags, &link);
282 if (!data->desc) {
283 dev_err(component->dev, "failed to prepare slave sg\n");
284 ret = -ENOMEM;
285 goto config_err;
286 }
287
288 if (!runtime->no_period_wakeup) {
289 data->desc->callback = sprd_pcm_dma_complete;
290 data->desc->callback_param = dma_private;
291 }
292 }
293
294 devm_kfree(dev: component->dev, p: sg);
295
296 return 0;
297
298config_err:
299 devm_kfree(dev: component->dev, p: sg);
300sg_err:
301 sprd_pcm_release_dma_channel(substream);
302 return ret;
303}
304
305static int sprd_pcm_hw_free(struct snd_soc_component *component,
306 struct snd_pcm_substream *substream)
307{
308 sprd_pcm_release_dma_channel(substream);
309
310 return 0;
311}
312
313static int sprd_pcm_trigger(struct snd_soc_component *component,
314 struct snd_pcm_substream *substream, int cmd)
315{
316 struct sprd_pcm_dma_private *dma_private =
317 substream->runtime->private_data;
318 int ret = 0, i;
319
320 switch (cmd) {
321 case SNDRV_PCM_TRIGGER_START:
322 for (i = 0; i < dma_private->hw_chan; i++) {
323 struct sprd_pcm_dma_data *data = &dma_private->data[i];
324
325 if (!data->desc)
326 continue;
327
328 data->cookie = dmaengine_submit(desc: data->desc);
329 ret = dma_submit_error(cookie: data->cookie);
330 if (ret) {
331 dev_err(component->dev,
332 "failed to submit dma request: %d\n",
333 ret);
334 return ret;
335 }
336
337 dma_async_issue_pending(chan: data->chan);
338 }
339
340 break;
341 case SNDRV_PCM_TRIGGER_RESUME:
342 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
343 for (i = 0; i < dma_private->hw_chan; i++) {
344 struct sprd_pcm_dma_data *data = &dma_private->data[i];
345
346 if (data->chan)
347 dmaengine_resume(chan: data->chan);
348 }
349
350 break;
351 case SNDRV_PCM_TRIGGER_STOP:
352 for (i = 0; i < dma_private->hw_chan; i++) {
353 struct sprd_pcm_dma_data *data = &dma_private->data[i];
354
355 if (data->chan)
356 dmaengine_terminate_async(chan: data->chan);
357 }
358
359 break;
360 case SNDRV_PCM_TRIGGER_SUSPEND:
361 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
362 for (i = 0; i < dma_private->hw_chan; i++) {
363 struct sprd_pcm_dma_data *data = &dma_private->data[i];
364
365 if (data->chan)
366 dmaengine_pause(chan: data->chan);
367 }
368
369 break;
370 default:
371 ret = -EINVAL;
372 }
373
374 return ret;
375}
376
377static snd_pcm_uframes_t sprd_pcm_pointer(struct snd_soc_component *component,
378 struct snd_pcm_substream *substream)
379{
380 struct snd_pcm_runtime *runtime = substream->runtime;
381 struct sprd_pcm_dma_private *dma_private = runtime->private_data;
382 int pointer[SPRD_PCM_CHANNEL_MAX];
383 int bytes_of_pointer = 0, sel_max = 0, i;
384 snd_pcm_uframes_t x;
385 struct dma_tx_state state;
386 enum dma_status status;
387
388 for (i = 0; i < dma_private->hw_chan; i++) {
389 struct sprd_pcm_dma_data *data = &dma_private->data[i];
390
391 if (!data->chan)
392 continue;
393
394 status = dmaengine_tx_status(chan: data->chan, cookie: data->cookie, state: &state);
395 if (status == DMA_ERROR) {
396 dev_err(component->dev,
397 "failed to get dma channel %d status\n", i);
398 return 0;
399 }
400
401 /*
402 * We just get current transfer address from the DMA engine, so
403 * we need convert to current pointer.
404 */
405 pointer[i] = state.residue - runtime->dma_addr -
406 i * dma_private->dma_addr_offset;
407
408 if (i == 0) {
409 bytes_of_pointer = pointer[i];
410 sel_max = pointer[i] < data->pre_pointer ? 1 : 0;
411 } else {
412 sel_max ^= pointer[i] < data->pre_pointer ? 1 : 0;
413
414 if (sel_max)
415 bytes_of_pointer =
416 max(pointer[i], pointer[i - 1]) << 1;
417 else
418 bytes_of_pointer =
419 min(pointer[i], pointer[i - 1]) << 1;
420 }
421
422 data->pre_pointer = pointer[i];
423 }
424
425 x = bytes_to_frames(runtime, size: bytes_of_pointer);
426 if (x == runtime->buffer_size)
427 x = 0;
428
429 return x;
430}
431
432static int sprd_pcm_new(struct snd_soc_component *component,
433 struct snd_soc_pcm_runtime *rtd)
434{
435 struct snd_card *card = rtd->card->snd_card;
436 struct snd_pcm *pcm = rtd->pcm;
437 int ret;
438
439 ret = dma_coerce_mask_and_coherent(dev: card->dev, DMA_BIT_MASK(32));
440 if (ret)
441 return ret;
442
443 return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
444 data: card->dev,
445 size: sprd_pcm_hardware.buffer_bytes_max);
446}
447
448static const struct snd_soc_component_driver sprd_soc_component = {
449 .name = DRV_NAME,
450 .open = sprd_pcm_open,
451 .close = sprd_pcm_close,
452 .hw_params = sprd_pcm_hw_params,
453 .hw_free = sprd_pcm_hw_free,
454 .trigger = sprd_pcm_trigger,
455 .pointer = sprd_pcm_pointer,
456 .pcm_construct = sprd_pcm_new,
457 .compress_ops = &sprd_platform_compress_ops,
458};
459
460static int sprd_soc_platform_probe(struct platform_device *pdev)
461{
462 struct device_node *np = pdev->dev.of_node;
463 int ret;
464
465 ret = of_reserved_mem_device_init_by_idx(dev: &pdev->dev, np, idx: 0);
466 if (ret)
467 dev_warn(&pdev->dev,
468 "no reserved DMA memory for audio platform device\n");
469
470 ret = devm_snd_soc_register_component(dev: &pdev->dev, component_driver: &sprd_soc_component,
471 NULL, num_dai: 0);
472 if (ret)
473 dev_err(&pdev->dev, "could not register platform:%d\n", ret);
474
475 return ret;
476}
477
478static const struct of_device_id sprd_pcm_of_match[] = {
479 { .compatible = "sprd,pcm-platform", },
480 { },
481};
482MODULE_DEVICE_TABLE(of, sprd_pcm_of_match);
483
484static struct platform_driver sprd_pcm_driver = {
485 .driver = {
486 .name = "sprd-pcm-audio",
487 .of_match_table = sprd_pcm_of_match,
488 },
489
490 .probe = sprd_soc_platform_probe,
491};
492
493module_platform_driver(sprd_pcm_driver);
494
495MODULE_DESCRIPTION("Spreadtrum ASoC PCM DMA");
496MODULE_LICENSE("GPL v2");
497MODULE_ALIAS("platform:sprd-audio");
498

source code of linux/sound/soc/sprd/sprd-pcm-dma.c