summaryrefslogtreecommitdiff
path: root/sound/soc/au1x/dbdma2.c
blob: 3d67e27fada9e795c1699b16741db2f111f0ab82 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Au12x0/Au1550 PSC ALSA ASoC audio support.
 *
 * (c) 2007-2008 MSC Vertriebsges.m.b.H.,
 *	Manuel Lauss <manuel.lauss@gmail.com>
 *
 * DMA glue for Au1x-PSC audio.
 */


#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>

#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>

#include <asm/mach-au1x00/au1000.h>
#include <asm/mach-au1x00/au1xxx_dbdma.h>
#include <asm/mach-au1x00/au1xxx_psc.h>

#include "psc.h"

/*#define PCM_DEBUG*/

#define DRV_NAME "dbdma2"

#define MSG(x...)	printk(KERN_INFO "au1xpsc_pcm: " x)
#ifdef PCM_DEBUG
#define DBG		MSG
#else
#define DBG(x...)	do {} while (0)
#endif

struct au1xpsc_audio_dmadata {
	/* DDMA control data */
	unsigned int ddma_id;		/* DDMA direction ID for this PSC */
	u32 ddma_chan;			/* DDMA context */

	/* PCM context (for irq handlers) */
	struct snd_pcm_substream *substream;
	unsigned long curr_period;	/* current segment DDMA is working on */
	unsigned long q_period;		/* queue period(s) */
	dma_addr_t dma_area;		/* address of queued DMA area */
	dma_addr_t dma_area_s;		/* start address of DMA area */
	unsigned long pos;		/* current byte position being played */
	unsigned long periods;		/* number of SG segments in total */
	unsigned long period_bytes;	/* size in bytes of one SG segment */

	/* runtime data */
	int msbits;
};

/*
 * These settings are somewhat okay, at least on my machine audio plays
 * almost skip-free. Especially the 64kB buffer seems to help a LOT.
 */
#define AU1XPSC_PERIOD_MIN_BYTES	1024
#define AU1XPSC_BUFFER_MIN_BYTES	65536

/* PCM hardware DMA capabilities - platform specific */
static const struct snd_pcm_hardware au1xpsc_pcm_hardware = {
	.info		  = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
			    SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH,
	.period_bytes_min = AU1XPSC_PERIOD_MIN_BYTES,
	.period_bytes_max = 4096 * 1024 - 1,
	.periods_min	  = 2,
	.periods_max	  = 4096,	/* 2 to as-much-as-you-like */
	.buffer_bytes_max = 4096 * 1024 - 1,
	.fifo_size	  = 16,		/* fifo entries of AC97/I2S PSC */
};

static void au1x_pcm_queue_tx(struct au1xpsc_audio_dmadata *cd)
{
	au1xxx_dbdma_put_source(cd->ddma_chan, cd->dma_area,
				cd->period_bytes, DDMA_FLAGS_IE);

	/* update next-to-queue period */
	++cd->q_period;
	cd->dma_area += cd->period_bytes;
	if (cd->q_period >= cd->periods) {
		cd->q_period = 0;
		cd->dma_area = cd->dma_area_s;
	}
}

static void au1x_pcm_queue_rx(struct au1xpsc_audio_dmadata *cd)
{
	au1xxx_dbdma_put_dest(cd->ddma_chan, cd->dma_area,
			      cd->period_bytes, DDMA_FLAGS_IE);

	/* update next-to-queue period */
	++cd->q_period;
	cd->dma_area += cd->period_bytes;
	if (cd->q_period >= cd->periods) {
		cd->q_period = 0;
		cd->dma_area = cd->dma_area_s;
	}
}

static void au1x_pcm_dmatx_cb(int irq, void *dev_id)
{
	struct au1xpsc_audio_dmadata *cd = dev_id;

	cd->pos += cd->period_bytes;
	if (++cd->curr_period >= cd->periods) {
		cd->pos = 0;
		cd->curr_period = 0;
	}
	snd_pcm_period_elapsed(cd->substream);
	au1x_pcm_queue_tx(cd);
}

static void au1x_pcm_dmarx_cb(int irq, void *dev_id)
{
	struct au1xpsc_audio_dmadata *cd = dev_id;

	cd->pos += cd->period_bytes;
	if (++cd->curr_period >= cd->periods) {
		cd->pos = 0;
		cd->curr_period = 0;
	}
	snd_pcm_period_elapsed(cd->substream);
	au1x_pcm_queue_rx(cd);
}

static void au1x_pcm_dbdma_free(struct au1xpsc_audio_dmadata *pcd)
{
	if (pcd->ddma_chan) {
		au1xxx_dbdma_stop(pcd->ddma_chan);
		au1xxx_dbdma_reset(pcd->ddma_chan);
		au1xxx_dbdma_chan_free(pcd->ddma_chan);
		pcd->ddma_chan = 0;
		pcd->msbits = 0;
	}
}

/* in case of missing DMA ring or changed TX-source / RX-dest bit widths,
 * allocate (or reallocate) a 2-descriptor DMA ring with bit depth according
 * to ALSA-supplied sample depth.  This is due to limitations in the dbdma api
 * (cannot adjust source/dest widths of already allocated descriptor ring).
 */
static int au1x_pcm_dbdma_realloc(struct au1xpsc_audio_dmadata *pcd,
				 int stype, int msbits)
{
	/* DMA only in 8/16/32 bit widths */
	if (msbits == 24)
		msbits = 32;

	/* check current config: correct bits and descriptors allocated? */
	if ((pcd->ddma_chan) && (msbits == pcd->msbits))
		goto out;	/* all ok! */

	au1x_pcm_dbdma_free(pcd);

	if (stype == SNDRV_PCM_STREAM_CAPTURE)
		pcd->ddma_chan = au1xxx_dbdma_chan_alloc(pcd->ddma_id,
					DSCR_CMD0_ALWAYS,
					au1x_pcm_dmarx_cb, (void *)pcd);
	else
		pcd->ddma_chan = au1xxx_dbdma_chan_alloc(DSCR_CMD0_ALWAYS,
					pcd->ddma_id,
					au1x_pcm_dmatx_cb, (void *)pcd);

	if (!pcd->ddma_chan)
		return -ENOMEM;

	au1xxx_dbdma_set_devwidth(pcd->ddma_chan, msbits);
	au1xxx_dbdma_ring_alloc(pcd->ddma_chan, 2);

	pcd->msbits = msbits;

	au1xxx_dbdma_stop(pcd->ddma_chan);
	au1xxx_dbdma_reset(pcd->ddma_chan);

out:
	return 0;
}

static inline struct au1xpsc_audio_dmadata *to_dmadata(struct snd_pcm_substream *ss,
						       struct snd_soc_component *component)
{
	struct au1xpsc_audio_dmadata *pcd = snd_soc_component_get_drvdata(component);
	return &pcd[ss->stream];
}

static int au1xpsc_pcm_hw_params(struct snd_soc_component *component,
				 struct snd_pcm_substream *substream,
				 struct snd_pcm_hw_params *params)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct au1xpsc_audio_dmadata *pcd;
	int stype, ret;

	stype = substream->stream;
	pcd = to_dmadata(substream, component);

	DBG("runtime->dma_area = 0x%08lx dma_addr_t = 0x%08lx dma_size = %zu "
	    "runtime->min_align %lu\n",
		(unsigned long)runtime->dma_area,
		(unsigned long)runtime->dma_addr, runtime->dma_bytes,
		runtime->min_align);

	DBG("bits %d  frags %d  frag_bytes %d  is_rx %d\n", params->msbits,
		params_periods(params), params_period_bytes(params), stype);

	ret = au1x_pcm_dbdma_realloc(pcd, stype, params->msbits);
	if (ret) {
		MSG("DDMA channel (re)alloc failed!\n");
		goto out;
	}

	pcd->substream = substream;
	pcd->period_bytes = params_period_bytes(params);
	pcd->periods = params_periods(params);
	pcd->dma_area_s = pcd->dma_area = runtime->dma_addr;
	pcd->q_period = 0;
	pcd->curr_period = 0;
	pcd->pos = 0;

	ret = 0;
out:
	return ret;
}

static int au1xpsc_pcm_prepare(struct snd_soc_component *component,
			       struct snd_pcm_substream *substream)
{
	struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream, component);

	au1xxx_dbdma_reset(pcd->ddma_chan);

	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
		au1x_pcm_queue_rx(pcd);
		au1x_pcm_queue_rx(pcd);
	} else {
		au1x_pcm_queue_tx(pcd);
		au1x_pcm_queue_tx(pcd);
	}

	return 0;
}

static int au1xpsc_pcm_trigger(struct snd_soc_component *component,
			       struct snd_pcm_substream *substream, int cmd)
{
	u32 c = to_dmadata(substream, component)->ddma_chan;

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
		au1xxx_dbdma_start(c);
		break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
		au1xxx_dbdma_stop(c);
		break;
	default:
		return -EINVAL;
	}
	return 0;
}

static snd_pcm_uframes_t
au1xpsc_pcm_pointer(struct snd_soc_component *component,
		    struct snd_pcm_substream *substream)
{
	return bytes_to_frames(substream->runtime,
			       to_dmadata(substream, component)->pos);
}

static int au1xpsc_pcm_open(struct snd_soc_component *component,
			    struct snd_pcm_substream *substream)
{
	struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream, component);
	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
	int stype = substream->stream, *dmaids;

	dmaids = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
	if (!dmaids)
		return -ENODEV;	/* whoa, has ordering changed? */

	pcd->ddma_id = dmaids[stype];

	snd_soc_set_runtime_hwparams(substream, &au1xpsc_pcm_hardware);
	return 0;
}

static int au1xpsc_pcm_close(struct snd_soc_component *component,
			     struct snd_pcm_substream *substream)
{
	au1x_pcm_dbdma_free(to_dmadata(substream, component));
	return 0;
}

static int au1xpsc_pcm_new(struct snd_soc_component *component,
			   struct snd_soc_pcm_runtime *rtd)
{
	struct snd_card *card = rtd->card->snd_card;
	struct snd_pcm *pcm = rtd->pcm;

	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
		card->dev, AU1XPSC_BUFFER_MIN_BYTES, (4096 * 1024) - 1);

	return 0;
}

/* au1xpsc audio platform */
static struct snd_soc_component_driver au1xpsc_soc_component = {
	.name		= DRV_NAME,
	.open		= au1xpsc_pcm_open,
	.close		= au1xpsc_pcm_close,
	.hw_params	= au1xpsc_pcm_hw_params,
	.prepare	= au1xpsc_pcm_prepare,
	.trigger	= au1xpsc_pcm_trigger,
	.pointer	= au1xpsc_pcm_pointer,
	.pcm_construct	= au1xpsc_pcm_new,
};

static int au1xpsc_pcm_drvprobe(struct platform_device *pdev)
{
	struct au1xpsc_audio_dmadata *dmadata;

	dmadata = devm_kcalloc(&pdev->dev,
			       2, sizeof(struct au1xpsc_audio_dmadata),
			       GFP_KERNEL);
	if (!dmadata)
		return -ENOMEM;

	platform_set_drvdata(pdev, dmadata);

	return devm_snd_soc_register_component(&pdev->dev,
					&au1xpsc_soc_component, NULL, 0);
}

static struct platform_driver au1xpsc_pcm_driver = {
	.driver	= {
		.name	= "au1xpsc-pcm",
	},
	.probe		= au1xpsc_pcm_drvprobe,
};

module_platform_driver(au1xpsc_pcm_driver);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Au12x0/Au1550 PSC Audio DMA driver");
MODULE_AUTHOR("Manuel Lauss");