[deliverable/linux.git] / sound / soc / kirkwood / kirkwood-dma.c

/*
 * kirkwood-dma.c
 *
 * (c) 2010 Arnaud Patard <apatard@mandriva.com>
 *
 *  This program is free software; you can redistribute  it and/or modify it
 *  under  the terms of  the GNU General  Public License as published by the
 *  Free Software Foundation;  either version 2 of the  License, or (at your
 *  option) any later version.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <linux/mbus.h>
#include <sound/soc.h>
#include "kirkwood-dma.h"
#include "kirkwood.h"

#define KIRKWOOD_RATES \
	(SNDRV_PCM_RATE_44100 | \
	 SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_96000)
#define KIRKWOOD_FORMATS \
	(SNDRV_PCM_FMTBIT_S16_LE | \
	 SNDRV_PCM_FMTBIT_S24_LE | \
	 SNDRV_PCM_FMTBIT_S32_LE)

struct kirkwood_dma_priv {
	struct snd_pcm_substream *play_stream;
	struct snd_pcm_substream *rec_stream;
	struct kirkwood_dma_data *data;
};

static struct snd_pcm_hardware kirkwood_dma_snd_hw = {
	.info = (SNDRV_PCM_INFO_INTERLEAVED |
		 SNDRV_PCM_INFO_MMAP |
		 SNDRV_PCM_INFO_MMAP_VALID |
		 SNDRV_PCM_INFO_BLOCK_TRANSFER |
		 SNDRV_PCM_INFO_PAUSE),
	.formats		= KIRKWOOD_FORMATS,
	.rates			= KIRKWOOD_RATES,
	.rate_min		= 44100,
	.rate_max		= 96000,
	.channels_min		= 1,
	.channels_max		= 2,
	.buffer_bytes_max	= KIRKWOOD_SND_MAX_PERIOD_BYTES * KIRKWOOD_SND_MAX_PERIODS,
	.period_bytes_min	= KIRKWOOD_SND_MIN_PERIOD_BYTES,
	.period_bytes_max	= KIRKWOOD_SND_MAX_PERIOD_BYTES,
	.periods_min		= KIRKWOOD_SND_MIN_PERIODS,
	.periods_max		= KIRKWOOD_SND_MAX_PERIODS,
	.fifo_size		= 0,
};

static u64 kirkwood_dma_dmamask = 0xFFFFFFFFUL;

static irqreturn_t kirkwood_dma_irq(int irq, void *dev_id)
{
	struct kirkwood_dma_priv *prdata = dev_id;
	struct kirkwood_dma_data *priv = prdata->data;
	unsigned long mask, status, cause;

	mask = readl(priv->io + KIRKWOOD_INT_MASK);
	status = readl(priv->io + KIRKWOOD_INT_CAUSE) & mask;

	cause = readl(priv->io + KIRKWOOD_ERR_CAUSE);
	if (unlikely(cause)) {
		printk(KERN_WARNING "%s: got err interrupt 0x%lx\n",
				__func__, cause);
		writel(cause, priv->io + KIRKWOOD_ERR_CAUSE);
		return IRQ_HANDLED;
	}

	/* we've enabled only bytes interrupts ... */
	if (status & ~(KIRKWOOD_INT_CAUSE_PLAY_BYTES | \
			KIRKWOOD_INT_CAUSE_REC_BYTES)) {
		printk(KERN_WARNING "%s: unexpected interrupt %lx\n",
			__func__, status);
		return IRQ_NONE;
	}

	/* ack int */
	writel(status, priv->io + KIRKWOOD_INT_CAUSE);

	if (status & KIRKWOOD_INT_CAUSE_PLAY_BYTES)
		snd_pcm_period_elapsed(prdata->play_stream);

	if (status & KIRKWOOD_INT_CAUSE_REC_BYTES)
		snd_pcm_period_elapsed(prdata->rec_stream);

	return IRQ_HANDLED;
}

static void kirkwood_dma_conf_mbus_windows(void __iomem *base, int win,
					unsigned long dma,
					struct mbus_dram_target_info *dram)
{
	int i;

	/* First disable and clear windows */
	writel(0, base + KIRKWOOD_AUDIO_WIN_CTRL_REG(win));
	writel(0, base + KIRKWOOD_AUDIO_WIN_BASE_REG(win));

	/* try to find matching cs for current dma address */
	for (i = 0; i < dram->num_cs; i++) {
		struct mbus_dram_window *cs = dram->cs + i;
		if ((cs->base & 0xffff0000) < (dma & 0xffff0000)) {
			writel(cs->base & 0xffff0000,
				base + KIRKWOOD_AUDIO_WIN_BASE_REG(win));
			writel(((cs->size - 1) & 0xffff0000) |
				(cs->mbus_attr << 8) |
				(dram->mbus_dram_target_id << 4) | 1,
				base + KIRKWOOD_AUDIO_WIN_CTRL_REG(win));
		}
	}
}

static int kirkwood_dma_open(struct snd_pcm_substream *substream)
{
	int err;
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
	struct snd_soc_dai *cpu_dai = soc_runtime->dai->cpu_dai;
	struct kirkwood_dma_data *priv;
	struct kirkwood_dma_priv *prdata = cpu_dai->private_data;
	unsigned long addr;

	priv = snd_soc_dai_get_dma_data(cpu_dai, substream);
	snd_soc_set_runtime_hwparams(substream, &kirkwood_dma_snd_hw);

	/* Ensure that all constraints linked to dma burst are fullfilled */
	err = snd_pcm_hw_constraint_minmax(runtime,
			SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
			priv->burst * 2,
			KIRKWOOD_AUDIO_BUF_MAX-1);
	if (err < 0)
		return err;

	err = snd_pcm_hw_constraint_step(runtime, 0,
			SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
			priv->burst);
	if (err < 0)
		return err;

	err = snd_pcm_hw_constraint_step(substream->runtime, 0,
			 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
			 priv->burst);
	if (err < 0)
		return err;

	if (soc_runtime->dai->cpu_dai->private_data == NULL) {
		prdata = kzalloc(sizeof(struct kirkwood_dma_priv), GFP_KERNEL);
		if (prdata == NULL)
			return -ENOMEM;

		prdata->data = priv;

		err = request_irq(priv->irq, kirkwood_dma_irq, IRQF_SHARED,
				  "kirkwood-i2s", prdata);
		if (err) {
			kfree(prdata);
			return -EBUSY;
		}

		soc_runtime->dai->cpu_dai->private_data = prdata;

		/*
		 * Enable Error interrupts. We're only ack'ing them but
		 * it's usefull for diagnostics
		 */
		writel((unsigned long)-1, priv->io + KIRKWOOD_ERR_MASK);
	}

	addr = virt_to_phys(substream->dma_buffer.area);
	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
		prdata->play_stream = substream;
		kirkwood_dma_conf_mbus_windows(priv->io,
			KIRKWOOD_PLAYBACK_WIN, addr, priv->dram);
	} else {
		prdata->rec_stream = substream;
		kirkwood_dma_conf_mbus_windows(priv->io,
			KIRKWOOD_RECORD_WIN, addr, priv->dram);
	}

	return 0;
}

static int kirkwood_dma_close(struct snd_pcm_substream *substream)
{
	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
	struct snd_soc_dai *cpu_dai = soc_runtime->dai->cpu_dai;
	struct kirkwood_dma_priv *prdata = cpu_dai->private_data;
	struct kirkwood_dma_data *priv;

	priv = snd_soc_dai_get_dma_data(cpu_dai, substream);

	if (!prdata || !priv)
		return 0;

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
		prdata->play_stream = NULL;
	else
		prdata->rec_stream = NULL;

	if (!prdata->play_stream && !prdata->rec_stream) {
		writel(0, priv->io + KIRKWOOD_ERR_MASK);
		free_irq(priv->irq, prdata);
		kfree(prdata);
		soc_runtime->dai->cpu_dai->private_data = NULL;
	}

	return 0;
}

static int kirkwood_dma_hw_params(struct snd_pcm_substream *substream,
				struct snd_pcm_hw_params *params)
{
	struct snd_pcm_runtime *runtime = substream->runtime;

	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
	runtime->dma_bytes = params_buffer_bytes(params);

	return 0;
}

static int kirkwood_dma_hw_free(struct snd_pcm_substream *substream)
{
	snd_pcm_set_runtime_buffer(substream, NULL);
	return 0;
}

static int kirkwood_dma_prepare(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
	struct snd_soc_dai *cpu_dai = soc_runtime->dai->cpu_dai;
	struct kirkwood_dma_data *priv;
	unsigned long size, count;

	priv = snd_soc_dai_get_dma_data(cpu_dai, substream);

	/* compute buffer size in term of "words" as requested in specs */
	size = frames_to_bytes(runtime, runtime->buffer_size);
	size = (size>>2)-1;
	count = snd_pcm_lib_period_bytes(substream);

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
		writel(count, priv->io + KIRKWOOD_PLAY_BYTE_INT_COUNT);
		writel(runtime->dma_addr, priv->io + KIRKWOOD_PLAY_BUF_ADDR);
		writel(size, priv->io + KIRKWOOD_PLAY_BUF_SIZE);
	} else {
		writel(count, priv->io + KIRKWOOD_REC_BYTE_INT_COUNT);
		writel(runtime->dma_addr, priv->io + KIRKWOOD_REC_BUF_ADDR);
		writel(size, priv->io + KIRKWOOD_REC_BUF_SIZE);
	}


	return 0;
}

static snd_pcm_uframes_t kirkwood_dma_pointer(struct snd_pcm_substream
						*substream)
{
	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
	struct snd_soc_dai *cpu_dai = soc_runtime->dai->cpu_dai;
	struct kirkwood_dma_data *priv;
	snd_pcm_uframes_t count;

	priv = snd_soc_dai_get_dma_data(cpu_dai, substream);

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
		count = bytes_to_frames(substream->runtime,
			readl(priv->io + KIRKWOOD_PLAY_BYTE_COUNT));
	else
		count = bytes_to_frames(substream->runtime,
			readl(priv->io + KIRKWOOD_REC_BYTE_COUNT));

	return count;
}

struct snd_pcm_ops kirkwood_dma_ops = {
	.open =		kirkwood_dma_open,
	.close =        kirkwood_dma_close,
	.ioctl =	snd_pcm_lib_ioctl,
	.hw_params =	kirkwood_dma_hw_params,
	.hw_free =      kirkwood_dma_hw_free,
	.prepare =      kirkwood_dma_prepare,
	.pointer =	kirkwood_dma_pointer,
};

static int kirkwood_dma_preallocate_dma_buffer(struct snd_pcm *pcm,
		int stream)
{
	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
	struct snd_dma_buffer *buf = &substream->dma_buffer;
	size_t size = kirkwood_dma_snd_hw.buffer_bytes_max;

	buf->dev.type = SNDRV_DMA_TYPE_DEV;
	buf->dev.dev = pcm->card->dev;
	buf->area = dma_alloc_coherent(pcm->card->dev, size,
			&buf->addr, GFP_KERNEL);
	if (!buf->area)
		return -ENOMEM;
	buf->bytes = size;
	buf->private_data = NULL;

	return 0;
}

static int kirkwood_dma_new(struct snd_card *card,
		struct snd_soc_dai *dai, struct snd_pcm *pcm)
{
	int ret;

	if (!card->dev->dma_mask)
		card->dev->dma_mask = &kirkwood_dma_dmamask;
	if (!card->dev->coherent_dma_mask)
		card->dev->coherent_dma_mask = 0xffffffff;

	if (dai->playback.channels_min) {
		ret = kirkwood_dma_preallocate_dma_buffer(pcm,
				SNDRV_PCM_STREAM_PLAYBACK);
		if (ret)
			return ret;
	}

	if (dai->capture.channels_min) {
		ret = kirkwood_dma_preallocate_dma_buffer(pcm,
				SNDRV_PCM_STREAM_CAPTURE);
		if (ret)
			return ret;
	}

	return 0;
}

static void kirkwood_dma_free_dma_buffers(struct snd_pcm *pcm)
{
	struct snd_pcm_substream *substream;
	struct snd_dma_buffer *buf;
	int stream;

	for (stream = 0; stream < 2; stream++) {
		substream = pcm->streams[stream].substream;
		if (!substream)
			continue;
		buf = &substream->dma_buffer;
		if (!buf->area)
			continue;

		dma_free_coherent(pcm->card->dev, buf->bytes,
				buf->area, buf->addr);
		buf->area = NULL;
	}
}

struct snd_soc_platform kirkwood_soc_platform = {
	.name		= "kirkwood-dma",
	.pcm_ops	= &kirkwood_dma_ops,
	.pcm_new	= kirkwood_dma_new,
	.pcm_free	= kirkwood_dma_free_dma_buffers,
};
EXPORT_SYMBOL_GPL(kirkwood_soc_platform);

static int __init kirkwood_soc_platform_init(void)
{
	return snd_soc_register_platform(&kirkwood_soc_platform);
}
module_init(kirkwood_soc_platform_init);

static void __exit kirkwood_soc_platform_exit(void)
{
	snd_soc_unregister_platform(&kirkwood_soc_platform);
}
module_exit(kirkwood_soc_platform_exit);

MODULE_AUTHOR("Arnaud Patard <apatard@mandriva.com>");
MODULE_DESCRIPTION("Marvell Kirkwood Audio DMA module");
MODULE_LICENSE("GPL");
Commit	Line	Data
f9b95980	1	/*
	2	* kirkwood-dma.c
	3	*
	4	* (c) 2010 Arnaud Patard <apatard@mandriva.com>
	5	*
	6	* This program is free software; you can redistribute it and/or modify it
	7	* under the terms of the GNU General Public License as published by the
	8	* Free Software Foundation; either version 2 of the License, or (at your
	9	* option) any later version.
	10	*/
	11
	12	#include <linux/init.h>
	13	#include <linux/module.h>
	14	#include <linux/device.h>
	15	#include <linux/io.h>
	16	#include <linux/slab.h>
	17	#include <linux/interrupt.h>
	18	#include <linux/dma-mapping.h>
	19	#include <linux/mbus.h>
	20	#include <sound/soc.h>
	21	#include "kirkwood-dma.h"
	22	#include "kirkwood.h"
	23
	24	#define KIRKWOOD_RATES \
	25	(SNDRV_PCM_RATE_44100 \| \
	26	SNDRV_PCM_RATE_48000 \| SNDRV_PCM_RATE_96000)
	27	#define KIRKWOOD_FORMATS \
	28	(SNDRV_PCM_FMTBIT_S16_LE \| \
	29	SNDRV_PCM_FMTBIT_S24_LE \| \
	30	SNDRV_PCM_FMTBIT_S32_LE)
	31
	32	struct kirkwood_dma_priv {
	33	struct snd_pcm_substream *play_stream;
	34	struct snd_pcm_substream *rec_stream;
	35	struct kirkwood_dma_data *data;
	36	};
	37
	38	static struct snd_pcm_hardware kirkwood_dma_snd_hw = {
	39	.info = (SNDRV_PCM_INFO_INTERLEAVED \|
	40	SNDRV_PCM_INFO_MMAP \|
	41	SNDRV_PCM_INFO_MMAP_VALID \|
	42	SNDRV_PCM_INFO_BLOCK_TRANSFER \|
	43	SNDRV_PCM_INFO_PAUSE),
	44	.formats = KIRKWOOD_FORMATS,
	45	.rates = KIRKWOOD_RATES,
	46	.rate_min = 44100,
	47	.rate_max = 96000,
	48	.channels_min = 1,
	49	.channels_max = 2,
	50	.buffer_bytes_max = KIRKWOOD_SND_MAX_PERIOD_BYTES * KIRKWOOD_SND_MAX_PERIODS,
	51	.period_bytes_min = KIRKWOOD_SND_MIN_PERIOD_BYTES,
	52	.period_bytes_max = KIRKWOOD_SND_MAX_PERIOD_BYTES,
	53	.periods_min = KIRKWOOD_SND_MIN_PERIODS,
	54	.periods_max = KIRKWOOD_SND_MAX_PERIODS,
	55	.fifo_size = 0,
	56	};
	57
	58	static u64 kirkwood_dma_dmamask = 0xFFFFFFFFUL;
	59
	60	static irqreturn_t kirkwood_dma_irq(int irq, void *dev_id)
	61	{
	62	struct kirkwood_dma_priv *prdata = dev_id;
	63	struct kirkwood_dma_data *priv = prdata->data;
	64	unsigned long mask, status, cause;
65
66	mask = readl(priv->io + KIRKWOOD_INT_MASK);
67	status = readl(priv->io + KIRKWOOD_INT_CAUSE) & mask;
68
69	cause = readl(priv->io + KIRKWOOD_ERR_CAUSE);
70	if (unlikely(cause)) {
71	printk(KERN_WARNING "%s: got err interrupt 0x%lx\n",
72	__func__, cause);
73	writel(cause, priv->io + KIRKWOOD_ERR_CAUSE);
74	return IRQ_HANDLED;
75	}
76
77	/* we've enabled only bytes interrupts ... */
78	if (status & ~(KIRKWOOD_INT_CAUSE_PLAY_BYTES \| \
79	KIRKWOOD_INT_CAUSE_REC_BYTES)) {
80	printk(KERN_WARNING "%s: unexpected interrupt %lx\n",
81	__func__, status);
82	return IRQ_NONE;
83	}
84
85	/* ack int */
86	writel(status, priv->io + KIRKWOOD_INT_CAUSE);
87
88	if (status & KIRKWOOD_INT_CAUSE_PLAY_BYTES)
89	snd_pcm_period_elapsed(prdata->play_stream);
90
91	if (status & KIRKWOOD_INT_CAUSE_REC_BYTES)
92	snd_pcm_period_elapsed(prdata->rec_stream);
93
94	return IRQ_HANDLED;
95	}
96
97	static void kirkwood_dma_conf_mbus_windows(void __iomem *base, int win,
98	unsigned long dma,
99	struct mbus_dram_target_info *dram)
100	{
101	int i;
102
103	/* First disable and clear windows */
104	writel(0, base + KIRKWOOD_AUDIO_WIN_CTRL_REG(win));
105	writel(0, base + KIRKWOOD_AUDIO_WIN_BASE_REG(win));
106
107	/* try to find matching cs for current dma address */
108	for (i = 0; i < dram->num_cs; i++) {
109	struct mbus_dram_window *cs = dram->cs + i;
110	if ((cs->base & 0xffff0000) < (dma & 0xffff0000)) {
111	writel(cs->base & 0xffff0000,
112	base + KIRKWOOD_AUDIO_WIN_BASE_REG(win));
113	writel(((cs->size - 1) & 0xffff0000) \|
114	(cs->mbus_attr << 8) \|
115	(dram->mbus_dram_target_id << 4) \| 1,
116	base + KIRKWOOD_AUDIO_WIN_CTRL_REG(win));
117	}
118	}
119	}
120
121	static int kirkwood_dma_open(struct snd_pcm_substream *substream)
122	{
123	int err;
124	struct snd_pcm_runtime *runtime = substream->runtime;
125	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
126	struct snd_soc_dai *cpu_dai = soc_runtime->dai->cpu_dai;
127	struct kirkwood_dma_data *priv;
128	struct kirkwood_dma_priv *prdata = cpu_dai->private_data;
129	unsigned long addr;
130
131	priv = snd_soc_dai_get_dma_data(cpu_dai, substream);
132	snd_soc_set_runtime_hwparams(substream, &kirkwood_dma_snd_hw);
133
134	/* Ensure that all constraints linked to dma burst are fullfilled */
135	err = snd_pcm_hw_constraint_minmax(runtime,
136	SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
137	priv->burst * 2,
138	KIRKWOOD_AUDIO_BUF_MAX-1);
139	if (err < 0)
140	return err;
141
142	err = snd_pcm_hw_constraint_step(runtime, 0,
143	SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
144	priv->burst);
145	if (err < 0)
146	return err;
147
148	err = snd_pcm_hw_constraint_step(substream->runtime, 0,
149	SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
150	priv->burst);
151	if (err < 0)
152	return err;
153
154	if (soc_runtime->dai->cpu_dai->private_data == NULL) {
155	prdata = kzalloc(sizeof(struct kirkwood_dma_priv), GFP_KERNEL);
156	if (prdata == NULL)
157	return -ENOMEM;
158
159	prdata->data = priv;
160
161	err = request_irq(priv->irq, kirkwood_dma_irq, IRQF_SHARED,
162	"kirkwood-i2s", prdata);
163	if (err) {
164	kfree(prdata);
165	return -EBUSY;
166	}
167
168	soc_runtime->dai->cpu_dai->private_data = prdata;
169
170	/*
171	* Enable Error interrupts. We're only ack'ing them but
172	* it's usefull for diagnostics
173	*/
174	writel((unsigned long)-1, priv->io + KIRKWOOD_ERR_MASK);
175	}
176
177	addr = virt_to_phys(substream->dma_buffer.area);
178	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
179	prdata->play_stream = substream;
180	kirkwood_dma_conf_mbus_windows(priv->io,
181	KIRKWOOD_PLAYBACK_WIN, addr, priv->dram);
182	} else {
183	prdata->rec_stream = substream;
184	kirkwood_dma_conf_mbus_windows(priv->io,
185	KIRKWOOD_RECORD_WIN, addr, priv->dram);
186	}
187
188	return 0;
189	}
190
191	static int kirkwood_dma_close(struct snd_pcm_substream *substream)
192	{
193	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
194	struct snd_soc_dai *cpu_dai = soc_runtime->dai->cpu_dai;
195	struct kirkwood_dma_priv *prdata = cpu_dai->private_data;
196	struct kirkwood_dma_data *priv;
197
198	priv = snd_soc_dai_get_dma_data(cpu_dai, substream);
199
200	if (!prdata \|\| !priv)
201	return 0;
202
203	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
204	prdata->play_stream = NULL;
205	else
206	prdata->rec_stream = NULL;
207
208	if (!prdata->play_stream && !prdata->rec_stream) {
209	writel(0, priv->io + KIRKWOOD_ERR_MASK);
210	free_irq(priv->irq, prdata);
211	kfree(prdata);
212	soc_runtime->dai->cpu_dai->private_data = NULL;
213	}
214
215	return 0;
216	}
217
218	static int kirkwood_dma_hw_params(struct snd_pcm_substream *substream,
219	struct snd_pcm_hw_params *params)
220	{
221	struct snd_pcm_runtime *runtime = substream->runtime;
222
223	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
224	runtime->dma_bytes = params_buffer_bytes(params);
225
226	return 0;
227	}
228
229	static int kirkwood_dma_hw_free(struct snd_pcm_substream *substream)
230	{
231	snd_pcm_set_runtime_buffer(substream, NULL);
232	return 0;
233	}
234
235	static int kirkwood_dma_prepare(struct snd_pcm_substream *substream)
236	{
237	struct snd_pcm_runtime *runtime = substream->runtime;
238	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
239	struct snd_soc_dai *cpu_dai = soc_runtime->dai->cpu_dai;
240	struct kirkwood_dma_data *priv;
241	unsigned long size, count;
242
243	priv = snd_soc_dai_get_dma_data(cpu_dai, substream);
244
245	/* compute buffer size in term of "words" as requested in specs */
246	size = frames_to_bytes(runtime, runtime->buffer_size);
247	size = (size>>2)-1;
248	count = snd_pcm_lib_period_bytes(substream);
249
250	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
251	writel(count, priv->io + KIRKWOOD_PLAY_BYTE_INT_COUNT);
252	writel(runtime->dma_addr, priv->io + KIRKWOOD_PLAY_BUF_ADDR);
253	writel(size, priv->io + KIRKWOOD_PLAY_BUF_SIZE);
254	} else {
255	writel(count, priv->io + KIRKWOOD_REC_BYTE_INT_COUNT);
256	writel(runtime->dma_addr, priv->io + KIRKWOOD_REC_BUF_ADDR);
257	writel(size, priv->io + KIRKWOOD_REC_BUF_SIZE);
258	}
259
260
261	return 0;
262	}
263
264	static snd_pcm_uframes_t kirkwood_dma_pointer(struct snd_pcm_substream
265	*substream)
266	{
267	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
268	struct snd_soc_dai *cpu_dai = soc_runtime->dai->cpu_dai;
269	struct kirkwood_dma_data *priv;
270	snd_pcm_uframes_t count;
271
272	priv = snd_soc_dai_get_dma_data(cpu_dai, substream);
273
274	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
275	count = bytes_to_frames(substream->runtime,
276	readl(priv->io + KIRKWOOD_PLAY_BYTE_COUNT));
277	else
278	count = bytes_to_frames(substream->runtime,
279	readl(priv->io + KIRKWOOD_REC_BYTE_COUNT));
280
281	return count;
282	}
283
284	struct snd_pcm_ops kirkwood_dma_ops = {
285	.open = kirkwood_dma_open,
286	.close = kirkwood_dma_close,
287	.ioctl = snd_pcm_lib_ioctl,
288	.hw_params = kirkwood_dma_hw_params,
289	.hw_free = kirkwood_dma_hw_free,
290	.prepare = kirkwood_dma_prepare,
291	.pointer = kirkwood_dma_pointer,
292	};
293
294	static int kirkwood_dma_preallocate_dma_buffer(struct snd_pcm *pcm,
295	int stream)
296	{
297	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
298	struct snd_dma_buffer *buf = &substream->dma_buffer;
299	size_t size = kirkwood_dma_snd_hw.buffer_bytes_max;
300
301	buf->dev.type = SNDRV_DMA_TYPE_DEV;
302	buf->dev.dev = pcm->card->dev;
303	buf->area = dma_alloc_coherent(pcm->card->dev, size,
304	&buf->addr, GFP_KERNEL);
305	if (!buf->area)
306	return -ENOMEM;
307	buf->bytes = size;
308	buf->private_data = NULL;
309
310	return 0;
311	}
312
313	static int kirkwood_dma_new(struct snd_card *card,
314	struct snd_soc_dai dai, struct snd_pcm pcm)
315	{
316	int ret;
317
318	if (!card->dev->dma_mask)
319	card->dev->dma_mask = &kirkwood_dma_dmamask;
320	if (!card->dev->coherent_dma_mask)
321	card->dev->coherent_dma_mask = 0xffffffff;
322
323	if (dai->playback.channels_min) {
324	ret = kirkwood_dma_preallocate_dma_buffer(pcm,
325	SNDRV_PCM_STREAM_PLAYBACK);
326	if (ret)
327	return ret;
328	}
329
330	if (dai->capture.channels_min) {
331	ret = kirkwood_dma_preallocate_dma_buffer(pcm,
332	SNDRV_PCM_STREAM_CAPTURE);
333	if (ret)
334	return ret;
335	}
336
337	return 0;
338	}
339
340	static void kirkwood_dma_free_dma_buffers(struct snd_pcm *pcm)
341	{
342	struct snd_pcm_substream *substream;
343	struct snd_dma_buffer *buf;
344	int stream;
345
346	for (stream = 0; stream < 2; stream++) {
347	substream = pcm->streams[stream].substream;
348	if (!substream)
349	continue;
350	buf = &substream->dma_buffer;
351	if (!buf->area)
352	continue;
353
354	dma_free_coherent(pcm->card->dev, buf->bytes,
355	buf->area, buf->addr);
356	buf->area = NULL;
357	}
358	}
359
360	struct snd_soc_platform kirkwood_soc_platform = {
361	.name = "kirkwood-dma",
362	.pcm_ops = &kirkwood_dma_ops,
363	.pcm_new = kirkwood_dma_new,
364	.pcm_free = kirkwood_dma_free_dma_buffers,
365	};
366	EXPORT_SYMBOL_GPL(kirkwood_soc_platform);
367
368	static int __init kirkwood_soc_platform_init(void)
369	{
370	return snd_soc_register_platform(&kirkwood_soc_platform);
371	}
372	module_init(kirkwood_soc_platform_init);
373
374	static void __exit kirkwood_soc_platform_exit(void)
375	{
376	snd_soc_unregister_platform(&kirkwood_soc_platform);
377	}
378	module_exit(kirkwood_soc_platform_exit);
379
380	MODULE_AUTHOR("Arnaud Patard <apatard@mandriva.com>");
381	MODULE_DESCRIPTION("Marvell Kirkwood Audio DMA module");
382	MODULE_LICENSE("GPL");
383