Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
[muen/linux.git] / sound / core / pcm_dmaengine.c
1 /*
2  *  Copyright (C) 2012, Analog Devices Inc.
3  *      Author: Lars-Peter Clausen <lars@metafoo.de>
4  *
5  *  Based on:
6  *      imx-pcm-dma-mx2.c, Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
7  *      mxs-pcm.c, Copyright (C) 2011 Freescale Semiconductor, Inc.
8  *      ep93xx-pcm.c, Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
9  *                    Copyright (C) 2006 Applied Data Systems
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  *  You should have received a copy of the GNU General Public License along
17  *  with this program; if not, write to the Free Software Foundation, Inc.,
18  *  675 Mass Ave, Cambridge, MA 02139, USA.
19  *
20  */
21 #include <linux/module.h>
22 #include <linux/init.h>
23 #include <linux/dmaengine.h>
24 #include <linux/slab.h>
25 #include <sound/pcm.h>
26 #include <sound/pcm_params.h>
27 #include <sound/soc.h>
28
29 #include <sound/dmaengine_pcm.h>
30
31 struct dmaengine_pcm_runtime_data {
32         struct dma_chan *dma_chan;
33         dma_cookie_t cookie;
34
35         unsigned int pos;
36 };
37
38 static inline struct dmaengine_pcm_runtime_data *substream_to_prtd(
39         const struct snd_pcm_substream *substream)
40 {
41         return substream->runtime->private_data;
42 }
43
44 struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream)
45 {
46         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
47
48         return prtd->dma_chan;
49 }
50 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_get_chan);
51
52 /**
53  * snd_hwparams_to_dma_slave_config - Convert hw_params to dma_slave_config
54  * @substream: PCM substream
55  * @params: hw_params
56  * @slave_config: DMA slave config
57  *
58  * This function can be used to initialize a dma_slave_config from a substream
59  * and hw_params in a dmaengine based PCM driver implementation.
60  */
61 int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
62         const struct snd_pcm_hw_params *params,
63         struct dma_slave_config *slave_config)
64 {
65         enum dma_slave_buswidth buswidth;
66         int bits;
67
68         bits = params_physical_width(params);
69         if (bits < 8 || bits > 64)
70                 return -EINVAL;
71         else if (bits == 8)
72                 buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
73         else if (bits == 16)
74                 buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
75         else if (bits == 24)
76                 buswidth = DMA_SLAVE_BUSWIDTH_3_BYTES;
77         else if (bits <= 32)
78                 buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
79         else
80                 buswidth = DMA_SLAVE_BUSWIDTH_8_BYTES;
81
82         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
83                 slave_config->direction = DMA_MEM_TO_DEV;
84                 slave_config->dst_addr_width = buswidth;
85         } else {
86                 slave_config->direction = DMA_DEV_TO_MEM;
87                 slave_config->src_addr_width = buswidth;
88         }
89
90         slave_config->device_fc = false;
91
92         return 0;
93 }
94 EXPORT_SYMBOL_GPL(snd_hwparams_to_dma_slave_config);
95
96 /**
97  * snd_dmaengine_pcm_set_config_from_dai_data() - Initializes a dma slave config
98  *  using DAI DMA data.
99  * @substream: PCM substream
100  * @dma_data: DAI DMA data
101  * @slave_config: DMA slave configuration
102  *
103  * Initializes the {dst,src}_addr, {dst,src}_maxburst, {dst,src}_addr_width and
104  * slave_id fields of the DMA slave config from the same fields of the DAI DMA
105  * data struct. The src and dst fields will be initialized depending on the
106  * direction of the substream. If the substream is a playback stream the dst
107  * fields will be initialized, if it is a capture stream the src fields will be
108  * initialized. The {dst,src}_addr_width field will only be initialized if the
109  * SND_DMAENGINE_PCM_DAI_FLAG_PACK flag is set or if the addr_width field of
110  * the DAI DMA data struct is not equal to DMA_SLAVE_BUSWIDTH_UNDEFINED. If
111  * both conditions are met the latter takes priority.
112  */
113 void snd_dmaengine_pcm_set_config_from_dai_data(
114         const struct snd_pcm_substream *substream,
115         const struct snd_dmaengine_dai_dma_data *dma_data,
116         struct dma_slave_config *slave_config)
117 {
118         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
119                 slave_config->dst_addr = dma_data->addr;
120                 slave_config->dst_maxburst = dma_data->maxburst;
121                 if (dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)
122                         slave_config->dst_addr_width =
123                                 DMA_SLAVE_BUSWIDTH_UNDEFINED;
124                 if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED)
125                         slave_config->dst_addr_width = dma_data->addr_width;
126         } else {
127                 slave_config->src_addr = dma_data->addr;
128                 slave_config->src_maxburst = dma_data->maxburst;
129                 if (dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)
130                         slave_config->src_addr_width =
131                                 DMA_SLAVE_BUSWIDTH_UNDEFINED;
132                 if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED)
133                         slave_config->src_addr_width = dma_data->addr_width;
134         }
135
136         slave_config->slave_id = dma_data->slave_id;
137 }
138 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_set_config_from_dai_data);
139
140 static void dmaengine_pcm_dma_complete(void *arg)
141 {
142         struct snd_pcm_substream *substream = arg;
143         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
144
145         prtd->pos += snd_pcm_lib_period_bytes(substream);
146         if (prtd->pos >= snd_pcm_lib_buffer_bytes(substream))
147                 prtd->pos = 0;
148
149         snd_pcm_period_elapsed(substream);
150 }
151
152 static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream)
153 {
154         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
155         struct dma_chan *chan = prtd->dma_chan;
156         struct dma_async_tx_descriptor *desc;
157         enum dma_transfer_direction direction;
158         unsigned long flags = DMA_CTRL_ACK;
159
160         direction = snd_pcm_substream_to_dma_direction(substream);
161
162         if (!substream->runtime->no_period_wakeup)
163                 flags |= DMA_PREP_INTERRUPT;
164
165         prtd->pos = 0;
166         desc = dmaengine_prep_dma_cyclic(chan,
167                 substream->runtime->dma_addr,
168                 snd_pcm_lib_buffer_bytes(substream),
169                 snd_pcm_lib_period_bytes(substream), direction, flags);
170
171         if (!desc)
172                 return -ENOMEM;
173
174         desc->callback = dmaengine_pcm_dma_complete;
175         desc->callback_param = substream;
176         prtd->cookie = dmaengine_submit(desc);
177
178         return 0;
179 }
180
181 /**
182  * snd_dmaengine_pcm_trigger - dmaengine based PCM trigger implementation
183  * @substream: PCM substream
184  * @cmd: Trigger command
185  *
186  * Returns 0 on success, a negative error code otherwise.
187  *
188  * This function can be used as the PCM trigger callback for dmaengine based PCM
189  * driver implementations.
190  */
191 int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
192 {
193         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
194         struct snd_pcm_runtime *runtime = substream->runtime;
195         int ret;
196
197         switch (cmd) {
198         case SNDRV_PCM_TRIGGER_START:
199                 ret = dmaengine_pcm_prepare_and_submit(substream);
200                 if (ret)
201                         return ret;
202                 dma_async_issue_pending(prtd->dma_chan);
203                 break;
204         case SNDRV_PCM_TRIGGER_RESUME:
205         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
206                 dmaengine_resume(prtd->dma_chan);
207                 break;
208         case SNDRV_PCM_TRIGGER_SUSPEND:
209                 if (runtime->info & SNDRV_PCM_INFO_PAUSE)
210                         dmaengine_pause(prtd->dma_chan);
211                 else
212                         dmaengine_terminate_async(prtd->dma_chan);
213                 break;
214         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
215                 dmaengine_pause(prtd->dma_chan);
216                 break;
217         case SNDRV_PCM_TRIGGER_STOP:
218                 dmaengine_terminate_async(prtd->dma_chan);
219                 break;
220         default:
221                 return -EINVAL;
222         }
223
224         return 0;
225 }
226 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_trigger);
227
228 /**
229  * snd_dmaengine_pcm_pointer_no_residue - dmaengine based PCM pointer implementation
230  * @substream: PCM substream
231  *
232  * This function is deprecated and should not be used by new drivers, as its
233  * results may be unreliable.
234  */
235 snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream)
236 {
237         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
238         return bytes_to_frames(substream->runtime, prtd->pos);
239 }
240 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer_no_residue);
241
242 /**
243  * snd_dmaengine_pcm_pointer - dmaengine based PCM pointer implementation
244  * @substream: PCM substream
245  *
246  * This function can be used as the PCM pointer callback for dmaengine based PCM
247  * driver implementations.
248  */
249 snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream)
250 {
251         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
252         struct dma_tx_state state;
253         enum dma_status status;
254         unsigned int buf_size;
255         unsigned int pos = 0;
256
257         status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state);
258         if (status == DMA_IN_PROGRESS || status == DMA_PAUSED) {
259                 buf_size = snd_pcm_lib_buffer_bytes(substream);
260                 if (state.residue > 0 && state.residue <= buf_size)
261                         pos = buf_size - state.residue;
262         }
263
264         return bytes_to_frames(substream->runtime, pos);
265 }
266 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer);
267
268 /**
269  * snd_dmaengine_pcm_request_channel - Request channel for the dmaengine PCM
270  * @filter_fn: Filter function used to request the DMA channel
271  * @filter_data: Data passed to the DMA filter function
272  *
273  * Returns NULL or the requested DMA channel.
274  *
275  * This function request a DMA channel for usage with dmaengine PCM.
276  */
277 struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
278         void *filter_data)
279 {
280         dma_cap_mask_t mask;
281
282         dma_cap_zero(mask);
283         dma_cap_set(DMA_SLAVE, mask);
284         dma_cap_set(DMA_CYCLIC, mask);
285
286         return dma_request_channel(mask, filter_fn, filter_data);
287 }
288 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_request_channel);
289
290 /**
291  * snd_dmaengine_pcm_open - Open a dmaengine based PCM substream
292  * @substream: PCM substream
293  * @chan: DMA channel to use for data transfers
294  *
295  * Returns 0 on success, a negative error code otherwise.
296  *
297  * The function should usually be called from the pcm open callback. Note that
298  * this function will use private_data field of the substream's runtime. So it
299  * is not available to your pcm driver implementation.
300  */
301 int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
302         struct dma_chan *chan)
303 {
304         struct dmaengine_pcm_runtime_data *prtd;
305         int ret;
306
307         if (!chan)
308                 return -ENXIO;
309
310         ret = snd_pcm_hw_constraint_integer(substream->runtime,
311                                             SNDRV_PCM_HW_PARAM_PERIODS);
312         if (ret < 0)
313                 return ret;
314
315         prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);
316         if (!prtd)
317                 return -ENOMEM;
318
319         prtd->dma_chan = chan;
320
321         substream->runtime->private_data = prtd;
322
323         return 0;
324 }
325 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open);
326
327 /**
328  * snd_dmaengine_pcm_open_request_chan - Open a dmaengine based PCM substream and request channel
329  * @substream: PCM substream
330  * @filter_fn: Filter function used to request the DMA channel
331  * @filter_data: Data passed to the DMA filter function
332  *
333  * Returns 0 on success, a negative error code otherwise.
334  *
335  * This function will request a DMA channel using the passed filter function and
336  * data. The function should usually be called from the pcm open callback. Note
337  * that this function will use private_data field of the substream's runtime. So
338  * it is not available to your pcm driver implementation.
339  */
340 int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
341         dma_filter_fn filter_fn, void *filter_data)
342 {
343         return snd_dmaengine_pcm_open(substream,
344                     snd_dmaengine_pcm_request_channel(filter_fn, filter_data));
345 }
346 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open_request_chan);
347
348 /**
349  * snd_dmaengine_pcm_close - Close a dmaengine based PCM substream
350  * @substream: PCM substream
351  */
352 int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream)
353 {
354         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
355
356         dmaengine_synchronize(prtd->dma_chan);
357         kfree(prtd);
358
359         return 0;
360 }
361 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close);
362
363 /**
364  * snd_dmaengine_pcm_release_chan_close - Close a dmaengine based PCM substream and release channel
365  * @substream: PCM substream
366  *
367  * Releases the DMA channel associated with the PCM substream.
368  */
369 int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream)
370 {
371         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
372
373         dmaengine_synchronize(prtd->dma_chan);
374         dma_release_channel(prtd->dma_chan);
375         kfree(prtd);
376
377         return 0;
378 }
379 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close_release_chan);
380
381 MODULE_LICENSE("GPL");