1/*
2 * omap-pcm.c  --  ALSA PCM interface for the OMAP SoC
3 *
4 * Copyright (C) 2008 Nokia Corporation
5 *
6 * Contact: Jarkko Nikula <jarkko.nikula@bitmer.com>
7 *          Peter Ujfalusi <peter.ujfalusi@ti.com>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * version 2 as published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
21 * 02110-1301 USA
22 *
23 */
24
25#include <linux/dma-mapping.h>
26#include <linux/slab.h>
27#include <linux/module.h>
28#include <linux/omap-dma.h>
29#include <sound/core.h>
30#include <sound/pcm.h>
31#include <sound/pcm_params.h>
32#include <sound/dmaengine_pcm.h>
33#include <sound/soc.h>
34#include <sound/omap-pcm.h>
35
36#ifdef CONFIG_ARCH_OMAP1
37#define pcm_omap1510()	cpu_is_omap1510()
38#else
39#define pcm_omap1510()	0
40#endif
41
42static struct snd_pcm_hardware omap_pcm_hardware = {
43	.info			= SNDRV_PCM_INFO_MMAP |
44				  SNDRV_PCM_INFO_MMAP_VALID |
45				  SNDRV_PCM_INFO_INTERLEAVED |
46				  SNDRV_PCM_INFO_PAUSE |
47				  SNDRV_PCM_INFO_RESUME |
48				  SNDRV_PCM_INFO_NO_PERIOD_WAKEUP,
49	.period_bytes_min	= 32,
50	.period_bytes_max	= 64 * 1024,
51	.periods_min		= 2,
52	.periods_max		= 255,
53	.buffer_bytes_max	= 128 * 1024,
54};
55
56/* sDMA supports only 1, 2, and 4 byte transfer elements. */
57static void omap_pcm_limit_supported_formats(void)
58{
59	int i;
60
61	for (i = 0; i < SNDRV_PCM_FORMAT_LAST; i++) {
62		switch (snd_pcm_format_physical_width(i)) {
63		case 8:
64		case 16:
65		case 32:
66			omap_pcm_hardware.formats |= (1LL << i);
67			break;
68		default:
69			break;
70		}
71	}
72}
73
74/* this may get called several times by oss emulation */
75static int omap_pcm_hw_params(struct snd_pcm_substream *substream,
76			      struct snd_pcm_hw_params *params)
77{
78	struct snd_pcm_runtime *runtime = substream->runtime;
79	struct snd_soc_pcm_runtime *rtd = substream->private_data;
80	struct omap_pcm_dma_data *dma_data;
81	struct dma_slave_config config;
82	struct dma_chan *chan;
83	int err = 0;
84
85	dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
86
87	/* return if this is a bufferless transfer e.g.
88	 * codec <--> BT codec or GSM modem -- lg FIXME */
89	if (!dma_data)
90		return 0;
91
92	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
93	runtime->dma_bytes = params_buffer_bytes(params);
94
95	chan = snd_dmaengine_pcm_get_chan(substream);
96	if (!chan)
97		return -EINVAL;
98
99	/* fills in addr_width and direction */
100	err = snd_hwparams_to_dma_slave_config(substream, params, &config);
101	if (err)
102		return err;
103
104	snd_dmaengine_pcm_set_config_from_dai_data(substream,
105			snd_soc_dai_get_dma_data(rtd->cpu_dai, substream),
106			&config);
107
108	return dmaengine_slave_config(chan, &config);
109}
110
111static int omap_pcm_hw_free(struct snd_pcm_substream *substream)
112{
113	snd_pcm_set_runtime_buffer(substream, NULL);
114	return 0;
115}
116
117static snd_pcm_uframes_t omap_pcm_pointer(struct snd_pcm_substream *substream)
118{
119	snd_pcm_uframes_t offset;
120
121	if (pcm_omap1510())
122		offset = snd_dmaengine_pcm_pointer_no_residue(substream);
123	else
124		offset = snd_dmaengine_pcm_pointer(substream);
125
126	return offset;
127}
128
129static int omap_pcm_open(struct snd_pcm_substream *substream)
130{
131	struct snd_soc_pcm_runtime *rtd = substream->private_data;
132	struct snd_dmaengine_dai_dma_data *dma_data;
133	int ret;
134
135	snd_soc_set_runtime_hwparams(substream, &omap_pcm_hardware);
136
137	dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
138
139	/* DT boot: filter_data is the DMA name */
140	if (rtd->cpu_dai->dev->of_node) {
141		struct dma_chan *chan;
142
143		chan = dma_request_slave_channel(rtd->cpu_dai->dev,
144						 dma_data->filter_data);
145		ret = snd_dmaengine_pcm_open(substream, chan);
146	} else {
147		ret = snd_dmaengine_pcm_open_request_chan(substream,
148							  omap_dma_filter_fn,
149							  dma_data->filter_data);
150	}
151	return ret;
152}
153
154static int omap_pcm_mmap(struct snd_pcm_substream *substream,
155	struct vm_area_struct *vma)
156{
157	struct snd_pcm_runtime *runtime = substream->runtime;
158
159	return dma_mmap_writecombine(substream->pcm->card->dev, vma,
160				     runtime->dma_area,
161				     runtime->dma_addr,
162				     runtime->dma_bytes);
163}
164
165static struct snd_pcm_ops omap_pcm_ops = {
166	.open		= omap_pcm_open,
167	.close		= snd_dmaengine_pcm_close_release_chan,
168	.ioctl		= snd_pcm_lib_ioctl,
169	.hw_params	= omap_pcm_hw_params,
170	.hw_free	= omap_pcm_hw_free,
171	.trigger	= snd_dmaengine_pcm_trigger,
172	.pointer	= omap_pcm_pointer,
173	.mmap		= omap_pcm_mmap,
174};
175
176static int omap_pcm_preallocate_dma_buffer(struct snd_pcm *pcm,
177	int stream)
178{
179	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
180	struct snd_dma_buffer *buf = &substream->dma_buffer;
181	size_t size = omap_pcm_hardware.buffer_bytes_max;
182
183	buf->dev.type = SNDRV_DMA_TYPE_DEV;
184	buf->dev.dev = pcm->card->dev;
185	buf->private_data = NULL;
186	buf->area = dma_alloc_writecombine(pcm->card->dev, size,
187					   &buf->addr, GFP_KERNEL);
188	if (!buf->area)
189		return -ENOMEM;
190
191	buf->bytes = size;
192	return 0;
193}
194
195static void omap_pcm_free_dma_buffers(struct snd_pcm *pcm)
196{
197	struct snd_pcm_substream *substream;
198	struct snd_dma_buffer *buf;
199	int stream;
200
201	for (stream = 0; stream < 2; stream++) {
202		substream = pcm->streams[stream].substream;
203		if (!substream)
204			continue;
205
206		buf = &substream->dma_buffer;
207		if (!buf->area)
208			continue;
209
210		dma_free_writecombine(pcm->card->dev, buf->bytes,
211				      buf->area, buf->addr);
212		buf->area = NULL;
213	}
214}
215
216static int omap_pcm_new(struct snd_soc_pcm_runtime *rtd)
217{
218	struct snd_card *card = rtd->card->snd_card;
219	struct snd_pcm *pcm = rtd->pcm;
220	int ret;
221
222	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
223	if (ret)
224		return ret;
225
226	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
227		ret = omap_pcm_preallocate_dma_buffer(pcm,
228			SNDRV_PCM_STREAM_PLAYBACK);
229		if (ret)
230			goto out;
231	}
232
233	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
234		ret = omap_pcm_preallocate_dma_buffer(pcm,
235			SNDRV_PCM_STREAM_CAPTURE);
236		if (ret)
237			goto out;
238	}
239
240out:
241	/* free preallocated buffers in case of error */
242	if (ret)
243		omap_pcm_free_dma_buffers(pcm);
244
245	return ret;
246}
247
248static struct snd_soc_platform_driver omap_soc_platform = {
249	.ops		= &omap_pcm_ops,
250	.pcm_new	= omap_pcm_new,
251	.pcm_free	= omap_pcm_free_dma_buffers,
252};
253
254int omap_pcm_platform_register(struct device *dev)
255{
256	omap_pcm_limit_supported_formats();
257	return devm_snd_soc_register_platform(dev, &omap_soc_platform);
258}
259EXPORT_SYMBOL_GPL(omap_pcm_platform_register);
260
261MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@bitmer.com>");
262MODULE_DESCRIPTION("OMAP PCM DMA module");
263MODULE_LICENSE("GPL");
264