1/*
2 * linux/sound/arm/pxa2xx-pcm.c -- ALSA PCM interface for the Intel PXA2xx chip
3 *
4 * Author:	Nicolas Pitre
5 * Created:	Nov 30, 2004
6 * Copyright:	(C) 2004 MontaVista Software, Inc.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/module.h>
14#include <linux/init.h>
15#include <linux/platform_device.h>
16#include <linux/slab.h>
17#include <linux/dma-mapping.h>
18
19#include <sound/driver.h>
20#include <sound/core.h>
21#include <sound/pcm.h>
22#include <sound/pcm_params.h>
23#include <sound/soc.h>
24
25#include <asm/dma.h>
26#include <asm/hardware.h>
27#include <asm/arch/pxa-regs.h>
28#include <asm/arch/audio.h>
29
30#include "pxa2xx-pcm.h"
31
32static const struct snd_pcm_hardware pxa2xx_pcm_hardware = {
33	.info			= SNDRV_PCM_INFO_MMAP |
34				  SNDRV_PCM_INFO_MMAP_VALID |
35				  SNDRV_PCM_INFO_INTERLEAVED |
36				  SNDRV_PCM_INFO_PAUSE |
37				  SNDRV_PCM_INFO_RESUME,
38	.formats		= SNDRV_PCM_FMTBIT_S16_LE |
39					SNDRV_PCM_FMTBIT_S24_LE |
40					SNDRV_PCM_FMTBIT_S32_LE,
41	.period_bytes_min	= 32,
42	.period_bytes_max	= 8192 - 32,
43	.periods_min		= 1,
44	.periods_max		= PAGE_SIZE/sizeof(pxa_dma_desc),
45	.buffer_bytes_max	= 128 * 1024,
46	.fifo_size		= 32,
47};
48
49struct pxa2xx_runtime_data {
50	int dma_ch;
51	struct pxa2xx_pcm_dma_params *params;
52	pxa_dma_desc *dma_desc_array;
53	dma_addr_t dma_desc_array_phys;
54};
55
56static void pxa2xx_pcm_dma_irq(int dma_ch, void *dev_id)
57{
58	struct snd_pcm_substream *substream = dev_id;
59	struct pxa2xx_runtime_data *prtd = substream->runtime->private_data;
60	int dcsr;
61
62	dcsr = DCSR(dma_ch);
63	DCSR(dma_ch) = dcsr & ~DCSR_STOPIRQEN;
64
65	if (dcsr & DCSR_ENDINTR) {
66		snd_pcm_period_elapsed(substream);
67	} else {
68		printk( KERN_ERR "%s: DMA error on channel %d (DCSR=%#x)\n",
69			prtd->params->name, dma_ch, dcsr );
70	}
71}
72
73static int pxa2xx_pcm_hw_params(struct snd_pcm_substream *substream,
74	struct snd_pcm_hw_params *params)
75{
76	struct snd_pcm_runtime *runtime = substream->runtime;
77	struct pxa2xx_runtime_data *prtd = runtime->private_data;
78	struct snd_soc_pcm_runtime *rtd = substream->private_data;
79	struct pxa2xx_pcm_dma_params *dma = rtd->dai->cpu_dai->dma_data;
80	size_t totsize = params_buffer_bytes(params);
81	size_t period = params_period_bytes(params);
82	pxa_dma_desc *dma_desc;
83	dma_addr_t dma_buff_phys, next_desc_phys;
84	int ret;
85
86	 if (!dma)
87	 	return 0;
88
89	/* this may get called several times by oss emulation
90	 * with different params */
91	if (prtd->params == NULL) {
92		prtd->params = dma;
93		ret = pxa_request_dma(prtd->params->name, DMA_PRIO_LOW,
94			      pxa2xx_pcm_dma_irq, substream);
95		if (ret < 0)
96			return ret;
97		prtd->dma_ch = ret;
98	} else if (prtd->params != dma) {
99		pxa_free_dma(prtd->dma_ch);
100		prtd->params = dma;
101		ret = pxa_request_dma(prtd->params->name, DMA_PRIO_LOW,
102			      pxa2xx_pcm_dma_irq, substream);
103		if (ret < 0)
104			return ret;
105		prtd->dma_ch = ret;
106	}
107
108	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
109	runtime->dma_bytes = totsize;
110
111	dma_desc = prtd->dma_desc_array;
112	next_desc_phys = prtd->dma_desc_array_phys;
113	dma_buff_phys = runtime->dma_addr;
114	do {
115		next_desc_phys += sizeof(pxa_dma_desc);
116		dma_desc->ddadr = next_desc_phys;
117		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
118			dma_desc->dsadr = dma_buff_phys;
119			dma_desc->dtadr = prtd->params->dev_addr;
120		} else {
121			dma_desc->dsadr = prtd->params->dev_addr;
122			dma_desc->dtadr = dma_buff_phys;
123		}
124		if (period > totsize)
125			period = totsize;
126		dma_desc->dcmd = prtd->params->dcmd | period | DCMD_ENDIRQEN;
127		dma_desc++;
128		dma_buff_phys += period;
129	} while (totsize -= period);
130	dma_desc[-1].ddadr = prtd->dma_desc_array_phys;
131
132	return 0;
133}
134
135static int pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream)
136{
137	struct pxa2xx_runtime_data *prtd = substream->runtime->private_data;
138
139	if (prtd && prtd->params)
140		*prtd->params->drcmr = 0;
141
142	if (prtd->dma_ch) {
143		snd_pcm_set_runtime_buffer(substream, NULL);
144		pxa_free_dma(prtd->dma_ch);
145		prtd->dma_ch = 0;
146	}
147
148	return 0;
149}
150
151static int pxa2xx_pcm_prepare(struct snd_pcm_substream *substream)
152{
153	struct pxa2xx_runtime_data *prtd = substream->runtime->private_data;
154
155	DCSR(prtd->dma_ch) &= ~DCSR_RUN;
156	DCSR(prtd->dma_ch) = 0;
157	DCMD(prtd->dma_ch) = 0;
158	*prtd->params->drcmr = prtd->dma_ch | DRCMR_MAPVLD;
159
160	return 0;
161}
162
163static int pxa2xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
164{
165	struct pxa2xx_runtime_data *prtd = substream->runtime->private_data;
166	int ret = 0;
167
168	switch (cmd) {
169	case SNDRV_PCM_TRIGGER_START:
170		DDADR(prtd->dma_ch) = prtd->dma_desc_array_phys;
171		DCSR(prtd->dma_ch) = DCSR_RUN;
172		break;
173
174	case SNDRV_PCM_TRIGGER_STOP:
175	case SNDRV_PCM_TRIGGER_SUSPEND:
176	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
177		DCSR(prtd->dma_ch) &= ~DCSR_RUN;
178		break;
179
180	case SNDRV_PCM_TRIGGER_RESUME:
181		DCSR(prtd->dma_ch) |= DCSR_RUN;
182		break;
183	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
184		DDADR(prtd->dma_ch) = prtd->dma_desc_array_phys;
185		DCSR(prtd->dma_ch) |= DCSR_RUN;
186		break;
187
188	default:
189		ret = -EINVAL;
190	}
191
192	return ret;
193}
194
195static snd_pcm_uframes_t
196pxa2xx_pcm_pointer(struct snd_pcm_substream *substream)
197{
198	struct snd_pcm_runtime *runtime = substream->runtime;
199	struct pxa2xx_runtime_data *prtd = runtime->private_data;
200
201	dma_addr_t ptr = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
202			 DSADR(prtd->dma_ch) : DTADR(prtd->dma_ch);
203	snd_pcm_uframes_t x = bytes_to_frames(runtime, ptr - runtime->dma_addr);
204
205	if (x == runtime->buffer_size)
206		x = 0;
207	return x;
208}
209
210static int pxa2xx_pcm_open(struct snd_pcm_substream *substream)
211{
212	struct snd_pcm_runtime *runtime = substream->runtime;
213	struct pxa2xx_runtime_data *prtd;
214	int ret;
215
216	snd_soc_set_runtime_hwparams(substream, &pxa2xx_pcm_hardware);
217
218	/*
219	 * For mysterious reasons (and despite what the manual says)
220	 * playback samples are lost if the DMA count is not a multiple
221	 * of the DMA burst size.  Let's add a rule to enforce that.
222	 */
223	ret = snd_pcm_hw_constraint_step(runtime, 0,
224		SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 32);
225	if (ret)
226		goto out;
227
228	ret = snd_pcm_hw_constraint_step(runtime, 0,
229		SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 32);
230	if (ret)
231		goto out;
232
233	ret = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
234	if (ret < 0)
235		goto out;
236
237	prtd = kzalloc(sizeof(struct pxa2xx_runtime_data), GFP_KERNEL);
238	if (prtd == NULL) {
239		ret = -ENOMEM;
240		goto out;
241	}
242
243	prtd->dma_desc_array =
244		dma_alloc_writecombine(substream->pcm->card->dev, PAGE_SIZE,
245				       &prtd->dma_desc_array_phys, GFP_KERNEL);
246	if (!prtd->dma_desc_array) {
247		ret = -ENOMEM;
248		goto err1;
249	}
250
251	runtime->private_data = prtd;
252	return 0;
253
254 err1:
255	kfree(prtd);
256 out:
257	return ret;
258}
259
260static int pxa2xx_pcm_close(struct snd_pcm_substream *substream)
261{
262	struct snd_pcm_runtime *runtime = substream->runtime;
263	struct pxa2xx_runtime_data *prtd = runtime->private_data;
264
265	dma_free_writecombine(substream->pcm->card->dev, PAGE_SIZE,
266			      prtd->dma_desc_array, prtd->dma_desc_array_phys);
267	kfree(prtd);
268	return 0;
269}
270
271static int pxa2xx_pcm_mmap(struct snd_pcm_substream *substream,
272	struct vm_area_struct *vma)
273{
274	struct snd_pcm_runtime *runtime = substream->runtime;
275	return dma_mmap_writecombine(substream->pcm->card->dev, vma,
276				     runtime->dma_area,
277				     runtime->dma_addr,
278				     runtime->dma_bytes);
279}
280
281struct snd_pcm_ops pxa2xx_pcm_ops = {
282	.open		= pxa2xx_pcm_open,
283	.close		= pxa2xx_pcm_close,
284	.ioctl		= snd_pcm_lib_ioctl,
285	.hw_params	= pxa2xx_pcm_hw_params,
286	.hw_free	= pxa2xx_pcm_hw_free,
287	.prepare	= pxa2xx_pcm_prepare,
288	.trigger	= pxa2xx_pcm_trigger,
289	.pointer	= pxa2xx_pcm_pointer,
290	.mmap		= pxa2xx_pcm_mmap,
291};
292
293static int pxa2xx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
294{
295	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
296	struct snd_dma_buffer *buf = &substream->dma_buffer;
297	size_t size = pxa2xx_pcm_hardware.buffer_bytes_max;
298	buf->dev.type = SNDRV_DMA_TYPE_DEV;
299	buf->dev.dev = pcm->card->dev;
300	buf->private_data = NULL;
301	buf->area = dma_alloc_writecombine(pcm->card->dev, size,
302					   &buf->addr, GFP_KERNEL);
303	if (!buf->area)
304		return -ENOMEM;
305	buf->bytes = size;
306	return 0;
307}
308
309static void pxa2xx_pcm_free_dma_buffers(struct snd_pcm *pcm)
310{
311	struct snd_pcm_substream *substream;
312	struct snd_dma_buffer *buf;
313	int stream;
314
315	for (stream = 0; stream < 2; stream++) {
316		substream = pcm->streams[stream].substream;
317		if (!substream)
318			continue;
319
320		buf = &substream->dma_buffer;
321		if (!buf->area)
322			continue;
323
324		dma_free_writecombine(pcm->card->dev, buf->bytes,
325				      buf->area, buf->addr);
326		buf->area = NULL;
327	}
328}
329
330static u64 pxa2xx_pcm_dmamask = DMA_32BIT_MASK;
331
332int pxa2xx_pcm_new(struct snd_card *card, struct snd_soc_codec_dai *dai,
333	struct snd_pcm *pcm)
334{
335	int ret = 0;
336
337	if (!card->dev->dma_mask)
338		card->dev->dma_mask = &pxa2xx_pcm_dmamask;
339	if (!card->dev->coherent_dma_mask)
340		card->dev->coherent_dma_mask = DMA_32BIT_MASK;
341
342	if (dai->playback.channels_min) {
343		ret = pxa2xx_pcm_preallocate_dma_buffer(pcm,
344			SNDRV_PCM_STREAM_PLAYBACK);
345		if (ret)
346			goto out;
347	}
348
349	if (dai->capture.channels_min) {
350		ret = pxa2xx_pcm_preallocate_dma_buffer(pcm,
351			SNDRV_PCM_STREAM_CAPTURE);
352		if (ret)
353			goto out;
354	}
355 out:
356	return ret;
357}
358
359struct snd_soc_platform pxa2xx_soc_platform = {
360	.name		= "pxa2xx-audio",
361	.pcm_ops 	= &pxa2xx_pcm_ops,
362	.pcm_new	= pxa2xx_pcm_new,
363	.pcm_free	= pxa2xx_pcm_free_dma_buffers,
364};
365
366EXPORT_SYMBOL_GPL(pxa2xx_soc_platform);
367
368MODULE_AUTHOR("Nicolas Pitre");
369MODULE_DESCRIPTION("Intel PXA2xx PCM DMA module");
370MODULE_LICENSE("GPL");
371