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  1/*
  2 * Copyright (c) 2010 Nuvoton technology corporation.
  3 *
  4 * Wan ZongShun <mcuos.com@gmail.com>
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License as published by
  8 * the Free Software Foundation;version 2 of the License.
  9 *
 10 */
 11
 12#include <linux/module.h>
 13#include <linux/init.h>
 14#include <linux/io.h>
 15#include <linux/platform_device.h>
 16#include <linux/slab.h>
 17#include <linux/dma-mapping.h>
 18
 19#include <sound/core.h>
 20#include <sound/pcm.h>
 21#include <sound/pcm_params.h>
 22#include <sound/soc.h>
 23
 24#include <mach/hardware.h>
 25
 26#include "nuc900-audio.h"
 27
 28static const struct snd_pcm_hardware nuc900_pcm_hardware = {
 29	.info			= SNDRV_PCM_INFO_INTERLEAVED |
 30					SNDRV_PCM_INFO_BLOCK_TRANSFER |
 31					SNDRV_PCM_INFO_MMAP |
 32					SNDRV_PCM_INFO_MMAP_VALID |
 33					SNDRV_PCM_INFO_PAUSE |
 34					SNDRV_PCM_INFO_RESUME,
 35	.buffer_bytes_max	= 4*1024,
 36	.period_bytes_min	= 1*1024,
 37	.period_bytes_max	= 4*1024,
 38	.periods_min		= 1,
 39	.periods_max		= 1024,
 40};
 41
 42static int nuc900_dma_hw_params(struct snd_pcm_substream *substream,
 43	struct snd_pcm_hw_params *params)
 44{
 45	struct snd_pcm_runtime *runtime = substream->runtime;
 46	struct nuc900_audio *nuc900_audio = runtime->private_data;
 47	unsigned long flags;
 48	int ret = 0;
 49
 50	ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
 51	if (ret < 0)
 52		return ret;
 53
 54	spin_lock_irqsave(&nuc900_audio->lock, flags);
 55
 56	nuc900_audio->substream = substream;
 57	nuc900_audio->dma_addr[substream->stream] = runtime->dma_addr;
 58	nuc900_audio->buffersize[substream->stream] =
 59						params_buffer_bytes(params);
 60
 61	spin_unlock_irqrestore(&nuc900_audio->lock, flags);
 62
 63	return ret;
 64}
 65
 66static void nuc900_update_dma_register(struct snd_pcm_substream *substream,
 67				dma_addr_t dma_addr, size_t count)
 68{
 69	struct snd_pcm_runtime *runtime = substream->runtime;
 70	struct nuc900_audio *nuc900_audio = runtime->private_data;
 71	void __iomem *mmio_addr, *mmio_len;
 72
 73	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 74		mmio_addr = nuc900_audio->mmio + ACTL_PDSTB;
 75		mmio_len = nuc900_audio->mmio + ACTL_PDST_LENGTH;
 76	} else {
 77		mmio_addr = nuc900_audio->mmio + ACTL_RDSTB;
 78		mmio_len = nuc900_audio->mmio + ACTL_RDST_LENGTH;
 79	}
 80
 81	AUDIO_WRITE(mmio_addr, dma_addr);
 82	AUDIO_WRITE(mmio_len, count);
 83}
 84
 85static void nuc900_dma_start(struct snd_pcm_substream *substream)
 86{
 87	struct snd_pcm_runtime *runtime = substream->runtime;
 88	struct nuc900_audio *nuc900_audio = runtime->private_data;
 89	unsigned long val;
 90
 91	val = AUDIO_READ(nuc900_audio->mmio + ACTL_CON);
 92	val |= (T_DMA_IRQ | R_DMA_IRQ);
 93	AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val);
 94}
 95
 96static void nuc900_dma_stop(struct snd_pcm_substream *substream)
 97{
 98	struct snd_pcm_runtime *runtime = substream->runtime;
 99	struct nuc900_audio *nuc900_audio = runtime->private_data;
100	unsigned long val;
101
102	val = AUDIO_READ(nuc900_audio->mmio + ACTL_CON);
103	val &= ~(T_DMA_IRQ | R_DMA_IRQ);
104	AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val);
105}
106
107static irqreturn_t nuc900_dma_interrupt(int irq, void *dev_id)
108{
109	struct snd_pcm_substream *substream = dev_id;
110	struct nuc900_audio *nuc900_audio = substream->runtime->private_data;
111	unsigned long val;
112
113	spin_lock(&nuc900_audio->lock);
114
115	val = AUDIO_READ(nuc900_audio->mmio + ACTL_CON);
116
117	if (val & R_DMA_IRQ) {
118		AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val | R_DMA_IRQ);
119
120		val = AUDIO_READ(nuc900_audio->mmio + ACTL_RSR);
121
122		if (val & R_DMA_MIDDLE_IRQ) {
123			val |= R_DMA_MIDDLE_IRQ;
124			AUDIO_WRITE(nuc900_audio->mmio + ACTL_RSR, val);
125		}
126
127		if (val & R_DMA_END_IRQ) {
128			val |= R_DMA_END_IRQ;
129			AUDIO_WRITE(nuc900_audio->mmio + ACTL_RSR, val);
130		}
131	} else if (val & T_DMA_IRQ) {
132		AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val | T_DMA_IRQ);
133
134		val = AUDIO_READ(nuc900_audio->mmio + ACTL_PSR);
135
136		if (val & P_DMA_MIDDLE_IRQ) {
137			val |= P_DMA_MIDDLE_IRQ;
138			AUDIO_WRITE(nuc900_audio->mmio + ACTL_PSR, val);
139		}
140
141		if (val & P_DMA_END_IRQ) {
142			val |= P_DMA_END_IRQ;
143			AUDIO_WRITE(nuc900_audio->mmio + ACTL_PSR, val);
144		}
145	} else {
146		dev_err(nuc900_audio->dev, "Wrong DMA interrupt status!\n");
147		spin_unlock(&nuc900_audio->lock);
148		return IRQ_HANDLED;
149	}
150
151	spin_unlock(&nuc900_audio->lock);
152
153	snd_pcm_period_elapsed(substream);
154
155	return IRQ_HANDLED;
156}
157
158static int nuc900_dma_hw_free(struct snd_pcm_substream *substream)
159{
160	snd_pcm_lib_free_pages(substream);
161	return 0;
162}
163
164static int nuc900_dma_prepare(struct snd_pcm_substream *substream)
165{
166	struct snd_pcm_runtime *runtime = substream->runtime;
167	struct nuc900_audio *nuc900_audio = runtime->private_data;
168	unsigned long flags, val;
169	int ret = 0;
170
171	spin_lock_irqsave(&nuc900_audio->lock, flags);
172
173	nuc900_update_dma_register(substream,
174				nuc900_audio->dma_addr[substream->stream],
175				nuc900_audio->buffersize[substream->stream]);
176
177	val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
178
179	switch (runtime->channels) {
180	case 1:
181		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
182			val &= ~(PLAY_LEFT_CHNNEL | PLAY_RIGHT_CHNNEL);
183			val |= PLAY_RIGHT_CHNNEL;
184		} else {
185			val &= ~(RECORD_LEFT_CHNNEL | RECORD_RIGHT_CHNNEL);
186			val |= RECORD_RIGHT_CHNNEL;
187		}
188		AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);
189		break;
190	case 2:
191		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
192			val |= (PLAY_LEFT_CHNNEL | PLAY_RIGHT_CHNNEL);
193		else
194			val |= (RECORD_LEFT_CHNNEL | RECORD_RIGHT_CHNNEL);
195		AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);
196		break;
197	default:
198		ret = -EINVAL;
199	}
200	spin_unlock_irqrestore(&nuc900_audio->lock, flags);
201	return ret;
202}
203
204static int nuc900_dma_trigger(struct snd_pcm_substream *substream, int cmd)
205{
206	int ret = 0;
207
208	switch (cmd) {
209	case SNDRV_PCM_TRIGGER_START:
210	case SNDRV_PCM_TRIGGER_RESUME:
211		nuc900_dma_start(substream);
212		break;
213
214	case SNDRV_PCM_TRIGGER_STOP:
215	case SNDRV_PCM_TRIGGER_SUSPEND:
216		nuc900_dma_stop(substream);
217		break;
218
219	default:
220		ret = -EINVAL;
221		break;
222	}
223
224	return ret;
225}
226
227static int nuc900_dma_getposition(struct snd_pcm_substream *substream,
228					dma_addr_t *src, dma_addr_t *dst)
229{
230	struct snd_pcm_runtime *runtime = substream->runtime;
231	struct nuc900_audio *nuc900_audio = runtime->private_data;
232
233	if (src != NULL)
234		*src = AUDIO_READ(nuc900_audio->mmio + ACTL_PDSTC);
235
236	if (dst != NULL)
237		*dst = AUDIO_READ(nuc900_audio->mmio + ACTL_RDSTC);
238
239	return 0;
240}
241
242static snd_pcm_uframes_t nuc900_dma_pointer(struct snd_pcm_substream *substream)
243{
244	struct snd_pcm_runtime *runtime = substream->runtime;
245	dma_addr_t src, dst;
246	unsigned long res;
247
248	nuc900_dma_getposition(substream, &src, &dst);
249
250	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
251		res = dst - runtime->dma_addr;
252	else
253		res = src - runtime->dma_addr;
254
255	return bytes_to_frames(substream->runtime, res);
256}
257
258static int nuc900_dma_open(struct snd_pcm_substream *substream)
259{
260	struct snd_pcm_runtime *runtime = substream->runtime;
261	struct nuc900_audio *nuc900_audio;
262
263	snd_soc_set_runtime_hwparams(substream, &nuc900_pcm_hardware);
264
265	nuc900_audio = nuc900_ac97_data;
266
267	if (request_irq(nuc900_audio->irq_num, nuc900_dma_interrupt,
268			0, "nuc900-dma", substream))
269		return -EBUSY;
270
271	runtime->private_data = nuc900_audio;
272
273	return 0;
274}
275
276static int nuc900_dma_close(struct snd_pcm_substream *substream)
277{
278	struct snd_pcm_runtime *runtime = substream->runtime;
279	struct nuc900_audio *nuc900_audio = runtime->private_data;
280
281	free_irq(nuc900_audio->irq_num, substream);
282
283	return 0;
284}
285
286static int nuc900_dma_mmap(struct snd_pcm_substream *substream,
287	struct vm_area_struct *vma)
288{
289	struct snd_pcm_runtime *runtime = substream->runtime;
290
291	return dma_mmap_writecombine(substream->pcm->card->dev, vma,
292					runtime->dma_area,
293					runtime->dma_addr,
294					runtime->dma_bytes);
295}
296
297static struct snd_pcm_ops nuc900_dma_ops = {
298	.open		= nuc900_dma_open,
299	.close		= nuc900_dma_close,
300	.ioctl		= snd_pcm_lib_ioctl,
301	.hw_params	= nuc900_dma_hw_params,
302	.hw_free	= nuc900_dma_hw_free,
303	.prepare	= nuc900_dma_prepare,
304	.trigger	= nuc900_dma_trigger,
305	.pointer	= nuc900_dma_pointer,
306	.mmap		= nuc900_dma_mmap,
307};
308
309static void nuc900_dma_free_dma_buffers(struct snd_pcm *pcm)
310{
311	snd_pcm_lib_preallocate_free_for_all(pcm);
312}
313
314static int nuc900_dma_new(struct snd_soc_pcm_runtime *rtd)
315{
316	struct snd_card *card = rtd->card->snd_card;
317	struct snd_pcm *pcm = rtd->pcm;
318	int ret;
319
320	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
321	if (ret)
322		return ret;
323
324	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
325		card->dev, 4 * 1024, (4 * 1024) - 1);
326
327	return 0;
328}
329
330static struct snd_soc_platform_driver nuc900_soc_platform = {
331	.ops		= &nuc900_dma_ops,
332	.pcm_new	= nuc900_dma_new,
333	.pcm_free	= nuc900_dma_free_dma_buffers,
334};
335
336static int nuc900_soc_platform_probe(struct platform_device *pdev)
337{
338	return snd_soc_register_platform(&pdev->dev, &nuc900_soc_platform);
339}
340
341static int nuc900_soc_platform_remove(struct platform_device *pdev)
342{
343	snd_soc_unregister_platform(&pdev->dev);
344	return 0;
345}
346
347static struct platform_driver nuc900_pcm_driver = {
348	.driver = {
349			.name = "nuc900-pcm-audio",
350			.owner = THIS_MODULE,
351	},
352
353	.probe = nuc900_soc_platform_probe,
354	.remove = nuc900_soc_platform_remove,
355};
356
357module_platform_driver(nuc900_pcm_driver);
358
359MODULE_AUTHOR("Wan ZongShun, <mcuos.com@gmail.com>");
360MODULE_DESCRIPTION("nuc900 Audio DMA module");
361MODULE_LICENSE("GPL");