1 // SPDX-License-Identifier: GPL-2.0+
3 // Copyright (C) 2013, Analog Devices Inc.
4 // Author: Lars-Peter Clausen <lars@metafoo.de>
6 #include <linux/module.h>
7 #include <linux/init.h>
8 #include <linux/dmaengine.h>
9 #include <linux/slab.h>
10 #include <sound/pcm.h>
11 #include <sound/pcm_params.h>
12 #include <sound/soc.h>
13 #include <linux/dma-mapping.h>
16 #include <sound/dmaengine_pcm.h>
19 * The platforms dmaengine driver does not support reporting the amount of
20 * bytes that are still left to transfer.
22 #define SND_DMAENGINE_PCM_FLAG_NO_RESIDUE BIT(31)
24 static struct device *dmaengine_dma_dev(struct dmaengine_pcm *pcm,
25 struct snd_pcm_substream *substream)
27 if (!pcm->chan[substream->stream])
30 return pcm->chan[substream->stream]->device->dev;
34 * snd_dmaengine_pcm_prepare_slave_config() - Generic prepare_slave_config callback
35 * @substream: PCM substream
37 * @slave_config: DMA slave config to prepare
39 * This function can be used as a generic prepare_slave_config callback for
40 * platforms which make use of the snd_dmaengine_dai_dma_data struct for their
41 * DAI DMA data. Internally the function will first call
42 * snd_hwparams_to_dma_slave_config to fill in the slave config based on the
43 * hw_params, followed by snd_dmaengine_set_config_from_dai_data to fill in the
44 * remaining fields based on the DAI DMA data.
46 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
47 struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config)
49 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
50 struct snd_dmaengine_dai_dma_data *dma_data;
53 if (rtd->num_cpus > 1) {
55 "%s doesn't support Multi CPU yet\n", __func__);
59 dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
61 ret = snd_hwparams_to_dma_slave_config(substream, params, slave_config);
65 snd_dmaengine_pcm_set_config_from_dai_data(substream, dma_data,
70 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_prepare_slave_config);
72 static int dmaengine_pcm_hw_params(struct snd_soc_component *component,
73 struct snd_pcm_substream *substream,
74 struct snd_pcm_hw_params *params)
76 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
77 struct dma_chan *chan = snd_dmaengine_pcm_get_chan(substream);
78 int (*prepare_slave_config)(struct snd_pcm_substream *substream,
79 struct snd_pcm_hw_params *params,
80 struct dma_slave_config *slave_config);
81 struct dma_slave_config slave_config;
83 memset(&slave_config, 0, sizeof(slave_config));
86 prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config;
88 prepare_slave_config = pcm->config->prepare_slave_config;
90 if (prepare_slave_config) {
91 int ret = prepare_slave_config(substream, params, &slave_config);
95 ret = dmaengine_slave_config(chan, &slave_config);
104 dmaengine_pcm_set_runtime_hwparams(struct snd_soc_component *component,
105 struct snd_pcm_substream *substream)
107 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
108 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
109 struct device *dma_dev = dmaengine_dma_dev(pcm, substream);
110 struct dma_chan *chan = pcm->chan[substream->stream];
111 struct snd_dmaengine_dai_dma_data *dma_data;
112 struct snd_pcm_hardware hw;
114 if (rtd->num_cpus > 1) {
116 "%s doesn't support Multi CPU yet\n", __func__);
120 if (pcm->config && pcm->config->pcm_hardware)
121 return snd_soc_set_runtime_hwparams(substream,
122 pcm->config->pcm_hardware);
124 dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
126 memset(&hw, 0, sizeof(hw));
127 hw.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
128 SNDRV_PCM_INFO_INTERLEAVED;
130 hw.periods_max = UINT_MAX;
131 hw.period_bytes_min = 256;
132 hw.period_bytes_max = dma_get_max_seg_size(dma_dev);
133 hw.buffer_bytes_max = SIZE_MAX;
134 hw.fifo_size = dma_data->fifo_size;
136 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
137 hw.info |= SNDRV_PCM_INFO_BATCH;
140 * FIXME: Remove the return value check to align with the code
141 * before adding snd_dmaengine_pcm_refine_runtime_hwparams
144 snd_dmaengine_pcm_refine_runtime_hwparams(substream,
149 return snd_soc_set_runtime_hwparams(substream, &hw);
152 static int dmaengine_pcm_open(struct snd_soc_component *component,
153 struct snd_pcm_substream *substream)
155 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
156 struct dma_chan *chan = pcm->chan[substream->stream];
159 ret = dmaengine_pcm_set_runtime_hwparams(component, substream);
163 return snd_dmaengine_pcm_open(substream, chan);
166 static int dmaengine_pcm_close(struct snd_soc_component *component,
167 struct snd_pcm_substream *substream)
169 return snd_dmaengine_pcm_close(substream);
172 static int dmaengine_pcm_trigger(struct snd_soc_component *component,
173 struct snd_pcm_substream *substream, int cmd)
175 return snd_dmaengine_pcm_trigger(substream, cmd);
178 static struct dma_chan *dmaengine_pcm_compat_request_channel(
179 struct snd_soc_component *component,
180 struct snd_soc_pcm_runtime *rtd,
181 struct snd_pcm_substream *substream)
183 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
184 struct snd_dmaengine_dai_dma_data *dma_data;
185 dma_filter_fn fn = NULL;
187 if (rtd->num_cpus > 1) {
189 "%s doesn't support Multi CPU yet\n", __func__);
193 dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
195 if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) && pcm->chan[0])
198 if (pcm->config && pcm->config->compat_request_channel)
199 return pcm->config->compat_request_channel(rtd, substream);
202 fn = pcm->config->compat_filter_fn;
204 return snd_dmaengine_pcm_request_channel(fn, dma_data->filter_data);
207 static bool dmaengine_pcm_can_report_residue(struct device *dev,
208 struct dma_chan *chan)
210 struct dma_slave_caps dma_caps;
213 ret = dma_get_slave_caps(chan, &dma_caps);
215 dev_warn(dev, "Failed to get DMA channel capabilities, falling back to period counting: %d\n",
220 if (dma_caps.residue_granularity == DMA_RESIDUE_GRANULARITY_DESCRIPTOR)
226 static int dmaengine_pcm_new(struct snd_soc_component *component,
227 struct snd_soc_pcm_runtime *rtd)
229 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
230 const struct snd_dmaengine_pcm_config *config = pcm->config;
231 struct device *dev = component->dev;
232 size_t prealloc_buffer_size;
233 size_t max_buffer_size;
236 if (config && config->prealloc_buffer_size) {
237 prealloc_buffer_size = config->prealloc_buffer_size;
238 max_buffer_size = config->pcm_hardware->buffer_bytes_max;
240 prealloc_buffer_size = 512 * 1024;
241 max_buffer_size = SIZE_MAX;
244 for_each_pcm_streams(i) {
245 struct snd_pcm_substream *substream = rtd->pcm->streams[i].substream;
249 if (!pcm->chan[i] && config && config->chan_names[i])
250 pcm->chan[i] = dma_request_slave_channel(dev,
251 config->chan_names[i]);
253 if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) {
254 pcm->chan[i] = dmaengine_pcm_compat_request_channel(
255 component, rtd, substream);
259 dev_err(component->dev,
260 "Missing dma channel for stream: %d\n", i);
264 snd_pcm_set_managed_buffer(substream,
265 SNDRV_DMA_TYPE_DEV_IRAM,
266 dmaengine_dma_dev(pcm, substream),
267 prealloc_buffer_size,
270 if (!dmaengine_pcm_can_report_residue(dev, pcm->chan[i]))
271 pcm->flags |= SND_DMAENGINE_PCM_FLAG_NO_RESIDUE;
273 if (rtd->pcm->streams[i].pcm->name[0] == '\0') {
274 strscpy_pad(rtd->pcm->streams[i].pcm->name,
275 rtd->pcm->streams[i].pcm->id,
276 sizeof(rtd->pcm->streams[i].pcm->name));
283 static snd_pcm_uframes_t dmaengine_pcm_pointer(
284 struct snd_soc_component *component,
285 struct snd_pcm_substream *substream)
287 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
289 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
290 return snd_dmaengine_pcm_pointer_no_residue(substream);
292 return snd_dmaengine_pcm_pointer(substream);
295 static int dmaengine_copy_user(struct snd_soc_component *component,
296 struct snd_pcm_substream *substream,
297 int channel, unsigned long hwoff,
298 void __user *buf, unsigned long bytes)
300 struct snd_pcm_runtime *runtime = substream->runtime;
301 struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
302 int (*process)(struct snd_pcm_substream *substream,
303 int channel, unsigned long hwoff,
304 void *buf, unsigned long bytes) = pcm->config->process;
305 bool is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
306 void *dma_ptr = runtime->dma_area + hwoff +
307 channel * (runtime->dma_bytes / runtime->channels);
310 if (copy_from_user(dma_ptr, buf, bytes))
314 int ret = process(substream, channel, hwoff, (__force void *)buf, bytes);
320 if (copy_to_user(buf, dma_ptr, bytes))
326 static const struct snd_soc_component_driver dmaengine_pcm_component = {
327 .name = SND_DMAENGINE_PCM_DRV_NAME,
328 .probe_order = SND_SOC_COMP_ORDER_LATE,
329 .open = dmaengine_pcm_open,
330 .close = dmaengine_pcm_close,
331 .hw_params = dmaengine_pcm_hw_params,
332 .trigger = dmaengine_pcm_trigger,
333 .pointer = dmaengine_pcm_pointer,
334 .pcm_construct = dmaengine_pcm_new,
337 static const struct snd_soc_component_driver dmaengine_pcm_component_process = {
338 .name = SND_DMAENGINE_PCM_DRV_NAME,
339 .probe_order = SND_SOC_COMP_ORDER_LATE,
340 .open = dmaengine_pcm_open,
341 .close = dmaengine_pcm_close,
342 .hw_params = dmaengine_pcm_hw_params,
343 .trigger = dmaengine_pcm_trigger,
344 .pointer = dmaengine_pcm_pointer,
345 .copy_user = dmaengine_copy_user,
346 .pcm_construct = dmaengine_pcm_new,
349 static const char * const dmaengine_pcm_dma_channel_names[] = {
350 [SNDRV_PCM_STREAM_PLAYBACK] = "tx",
351 [SNDRV_PCM_STREAM_CAPTURE] = "rx",
354 static int dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm,
355 struct device *dev, const struct snd_dmaengine_pcm_config *config)
359 struct dma_chan *chan;
361 if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_DT) || (!dev->of_node &&
362 !(config && config->dma_dev && config->dma_dev->of_node)))
365 if (config && config->dma_dev) {
367 * If this warning is seen, it probably means that your Linux
368 * device structure does not match your HW device structure.
369 * It would be best to refactor the Linux device structure to
370 * correctly match the HW structure.
372 dev_warn(dev, "DMA channels sourced from device %s",
373 dev_name(config->dma_dev));
374 dev = config->dma_dev;
377 for_each_pcm_streams(i) {
378 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
381 name = dmaengine_pcm_dma_channel_names[i];
382 if (config && config->chan_names[i])
383 name = config->chan_names[i];
384 chan = dma_request_chan(dev, name);
387 * Only report probe deferral errors, channels
388 * might not be present for devices that
389 * support only TX or only RX.
391 if (PTR_ERR(chan) == -EPROBE_DEFER)
392 return -EPROBE_DEFER;
397 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
401 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
402 pcm->chan[1] = pcm->chan[0];
407 static void dmaengine_pcm_release_chan(struct dmaengine_pcm *pcm)
411 for_each_pcm_streams(i) {
414 dma_release_channel(pcm->chan[i]);
415 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
421 * snd_dmaengine_pcm_register - Register a dmaengine based PCM device
422 * @dev: The parent device for the PCM device
423 * @config: Platform specific PCM configuration
424 * @flags: Platform specific quirks
426 int snd_dmaengine_pcm_register(struct device *dev,
427 const struct snd_dmaengine_pcm_config *config, unsigned int flags)
429 const struct snd_soc_component_driver *driver;
430 struct dmaengine_pcm *pcm;
433 pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
437 #ifdef CONFIG_DEBUG_FS
438 pcm->component.debugfs_prefix = "dma";
440 pcm->config = config;
443 ret = dmaengine_pcm_request_chan_of(pcm, dev, config);
447 if (config && config->process)
448 driver = &dmaengine_pcm_component_process;
450 driver = &dmaengine_pcm_component;
452 ret = snd_soc_component_initialize(&pcm->component, driver, dev);
456 ret = snd_soc_add_component(&pcm->component, NULL, 0);
463 dmaengine_pcm_release_chan(pcm);
467 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_register);
470 * snd_dmaengine_pcm_unregister - Removes a dmaengine based PCM device
471 * @dev: Parent device the PCM was register with
473 * Removes a dmaengine based PCM device previously registered with
474 * snd_dmaengine_pcm_register.
476 void snd_dmaengine_pcm_unregister(struct device *dev)
478 struct snd_soc_component *component;
479 struct dmaengine_pcm *pcm;
481 component = snd_soc_lookup_component(dev, SND_DMAENGINE_PCM_DRV_NAME);
485 pcm = soc_component_to_pcm(component);
487 snd_soc_unregister_component_by_driver(dev, component->driver);
488 dmaengine_pcm_release_chan(pcm);
491 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_unregister);
493 MODULE_LICENSE("GPL");