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	return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
46}
47
48static void nuc900_update_dma_register(struct snd_pcm_substream *substream)
49{
50	struct snd_pcm_runtime *runtime = substream->runtime;
51	struct nuc900_audio *nuc900_audio = runtime->private_data;
52	void __iomem *mmio_addr, *mmio_len;
53
54	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
55		mmio_addr = nuc900_audio->mmio + ACTL_PDSTB;
56		mmio_len = nuc900_audio->mmio + ACTL_PDST_LENGTH;
57	} else {
58		mmio_addr = nuc900_audio->mmio + ACTL_RDSTB;
59		mmio_len = nuc900_audio->mmio + ACTL_RDST_LENGTH;
60	}
61
62	AUDIO_WRITE(mmio_addr, runtime->dma_addr);
63	AUDIO_WRITE(mmio_len, runtime->dma_bytes);
64}
65
66static void nuc900_dma_start(struct snd_pcm_substream *substream)
67{
68	struct snd_pcm_runtime *runtime = substream->runtime;
69	struct nuc900_audio *nuc900_audio = runtime->private_data;
70	unsigned long val;
71
72	val = AUDIO_READ(nuc900_audio->mmio + ACTL_CON);
73	val |= (T_DMA_IRQ | R_DMA_IRQ);
74	AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val);
75}
76
77static void nuc900_dma_stop(struct snd_pcm_substream *substream)
78{
79	struct snd_pcm_runtime *runtime = substream->runtime;
80	struct nuc900_audio *nuc900_audio = runtime->private_data;
81	unsigned long val;
82
83	val = AUDIO_READ(nuc900_audio->mmio + ACTL_CON);
84	val &= ~(T_DMA_IRQ | R_DMA_IRQ);
85	AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val);
86}
87
88static irqreturn_t nuc900_dma_interrupt(int irq, void *dev_id)
89{
90	struct snd_pcm_substream *substream = dev_id;
91	struct nuc900_audio *nuc900_audio = substream->runtime->private_data;
92	unsigned long val;
93
94	spin_lock(&nuc900_audio->lock);
95
96	val = AUDIO_READ(nuc900_audio->mmio + ACTL_CON);
97
98	if (val & R_DMA_IRQ) {
99		AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val | R_DMA_IRQ);
100
101		val = AUDIO_READ(nuc900_audio->mmio + ACTL_RSR);
102
103		if (val & R_DMA_MIDDLE_IRQ) {
104			val |= R_DMA_MIDDLE_IRQ;
105			AUDIO_WRITE(nuc900_audio->mmio + ACTL_RSR, val);
106		}
107
108		if (val & R_DMA_END_IRQ) {
109			val |= R_DMA_END_IRQ;
110			AUDIO_WRITE(nuc900_audio->mmio + ACTL_RSR, val);
111		}
112	} else if (val & T_DMA_IRQ) {
113		AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val | T_DMA_IRQ);
114
115		val = AUDIO_READ(nuc900_audio->mmio + ACTL_PSR);
116
117		if (val & P_DMA_MIDDLE_IRQ) {
118			val |= P_DMA_MIDDLE_IRQ;
119			AUDIO_WRITE(nuc900_audio->mmio + ACTL_PSR, val);
120		}
121
122		if (val & P_DMA_END_IRQ) {
123			val |= P_DMA_END_IRQ;
124			AUDIO_WRITE(nuc900_audio->mmio + ACTL_PSR, val);
125		}
126	} else {
127		dev_err(nuc900_audio->dev, "Wrong DMA interrupt status!\n");
128		spin_unlock(&nuc900_audio->lock);
129		return IRQ_HANDLED;
130	}
131
132	spin_unlock(&nuc900_audio->lock);
133
134	snd_pcm_period_elapsed(substream);
135
136	return IRQ_HANDLED;
137}
138
139static int nuc900_dma_hw_free(struct snd_pcm_substream *substream)
140{
141	snd_pcm_lib_free_pages(substream);
142	return 0;
143}
144
145static int nuc900_dma_prepare(struct snd_pcm_substream *substream)
146{
147	struct snd_pcm_runtime *runtime = substream->runtime;
148	struct nuc900_audio *nuc900_audio = runtime->private_data;
149	unsigned long flags, val;
150	int ret = 0;
151
152	spin_lock_irqsave(&nuc900_audio->lock, flags);
153
154	nuc900_update_dma_register(substream);
155
156	val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
157
158	switch (runtime->channels) {
159	case 1:
160		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
161			val &= ~(PLAY_LEFT_CHNNEL | PLAY_RIGHT_CHNNEL);
162			val |= PLAY_RIGHT_CHNNEL;
163		} else {
164			val &= ~(RECORD_LEFT_CHNNEL | RECORD_RIGHT_CHNNEL);
165			val |= RECORD_RIGHT_CHNNEL;
166		}
167		AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);
168		break;
169	case 2:
170		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
171			val |= (PLAY_LEFT_CHNNEL | PLAY_RIGHT_CHNNEL);
172		else
173			val |= (RECORD_LEFT_CHNNEL | RECORD_RIGHT_CHNNEL);
174		AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);
175		break;
176	default:
177		ret = -EINVAL;
178	}
179	spin_unlock_irqrestore(&nuc900_audio->lock, flags);
180	return ret;
181}
182
183static int nuc900_dma_trigger(struct snd_pcm_substream *substream, int cmd)
184{
185	int ret = 0;
186
187	switch (cmd) {
188	case SNDRV_PCM_TRIGGER_START:
189	case SNDRV_PCM_TRIGGER_RESUME:
190		nuc900_dma_start(substream);
191		break;
192
193	case SNDRV_PCM_TRIGGER_STOP:
194	case SNDRV_PCM_TRIGGER_SUSPEND:
195		nuc900_dma_stop(substream);
196		break;
197
198	default:
199		ret = -EINVAL;
200		break;
201	}
202
203	return ret;
204}
205
206static int nuc900_dma_getposition(struct snd_pcm_substream *substream,
207					dma_addr_t *src, dma_addr_t *dst)
208{
209	struct snd_pcm_runtime *runtime = substream->runtime;
210	struct nuc900_audio *nuc900_audio = runtime->private_data;
211
212	if (src != NULL)
213		*src = AUDIO_READ(nuc900_audio->mmio + ACTL_PDSTC);
214
215	if (dst != NULL)
216		*dst = AUDIO_READ(nuc900_audio->mmio + ACTL_RDSTC);
217
218	return 0;
219}
220
221static snd_pcm_uframes_t nuc900_dma_pointer(struct snd_pcm_substream *substream)
222{
223	struct snd_pcm_runtime *runtime = substream->runtime;
224	dma_addr_t src, dst;
225	unsigned long res;
226
227	nuc900_dma_getposition(substream, &src, &dst);
228
229	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
230		res = dst - runtime->dma_addr;
231	else
232		res = src - runtime->dma_addr;
233
234	return bytes_to_frames(substream->runtime, res);
235}
236
237static int nuc900_dma_open(struct snd_pcm_substream *substream)
238{
239	struct snd_pcm_runtime *runtime = substream->runtime;
240	struct nuc900_audio *nuc900_audio;
241
242	snd_soc_set_runtime_hwparams(substream, &nuc900_pcm_hardware);
243
244	nuc900_audio = nuc900_ac97_data;
245
246	if (request_irq(nuc900_audio->irq_num, nuc900_dma_interrupt,
247			0, "nuc900-dma", substream))
248		return -EBUSY;
249
250	runtime->private_data = nuc900_audio;
251
252	return 0;
253}
254
255static int nuc900_dma_close(struct snd_pcm_substream *substream)
256{
257	struct snd_pcm_runtime *runtime = substream->runtime;
258	struct nuc900_audio *nuc900_audio = runtime->private_data;
259
260	free_irq(nuc900_audio->irq_num, substream);
261
262	return 0;
263}
264
265static int nuc900_dma_mmap(struct snd_pcm_substream *substream,
266	struct vm_area_struct *vma)
267{
268	struct snd_pcm_runtime *runtime = substream->runtime;
269
270	return dma_mmap_writecombine(substream->pcm->card->dev, vma,
271					runtime->dma_area,
272					runtime->dma_addr,
273					runtime->dma_bytes);
274}
275
276static struct snd_pcm_ops nuc900_dma_ops = {
277	.open		= nuc900_dma_open,
278	.close		= nuc900_dma_close,
279	.ioctl		= snd_pcm_lib_ioctl,
280	.hw_params	= nuc900_dma_hw_params,
281	.hw_free	= nuc900_dma_hw_free,
282	.prepare	= nuc900_dma_prepare,
283	.trigger	= nuc900_dma_trigger,
284	.pointer	= nuc900_dma_pointer,
285	.mmap		= nuc900_dma_mmap,
286};
287
288static int nuc900_dma_new(struct snd_soc_pcm_runtime *rtd)
289{
290	struct snd_card *card = rtd->card->snd_card;
291	struct snd_pcm *pcm = rtd->pcm;
292	int ret;
293
294	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
295	if (ret)
296		return ret;
297
298	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
299		card->dev, 4 * 1024, (4 * 1024) - 1);
300
301	return 0;
302}
303
304static struct snd_soc_platform_driver nuc900_soc_platform = {
305	.ops		= &nuc900_dma_ops,
306	.pcm_new	= nuc900_dma_new,
307};
308
309static int nuc900_soc_platform_probe(struct platform_device *pdev)
310{
311	return snd_soc_register_platform(&pdev->dev, &nuc900_soc_platform);
312}
313
314static int nuc900_soc_platform_remove(struct platform_device *pdev)
315{
316	snd_soc_unregister_platform(&pdev->dev);
317	return 0;
318}
319
320static struct platform_driver nuc900_pcm_driver = {
321	.driver = {
322			.name = "nuc900-pcm-audio",
323	},
324
325	.probe = nuc900_soc_platform_probe,
326	.remove = nuc900_soc_platform_remove,
327};
328
329module_platform_driver(nuc900_pcm_driver);
330
331MODULE_AUTHOR("Wan ZongShun, <mcuos.com@gmail.com>");
332MODULE_DESCRIPTION("nuc900 Audio DMA module");
333MODULE_LICENSE("GPL");
334