summaryrefslogtreecommitdiffstats
path: root/sound/soc/adi/axi-i2s.c
blob: 4c23381727a1ed1c53406b596ff04d9cd2e68577 (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
/*
 * Copyright (C) 2012-2013, Analog Devices Inc.
 * Author: Lars-Peter Clausen <lars@metafoo.de>
 *
 * Licensed under the GPL-2.
 */

#include <linux/clk.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>

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

#define AXI_I2S_REG_RESET	0x00
#define AXI_I2S_REG_CTRL	0x04
#define AXI_I2S_REG_CLK_CTRL	0x08
#define AXI_I2S_REG_STATUS	0x10

#define AXI_I2S_REG_RX_FIFO	0x28
#define AXI_I2S_REG_TX_FIFO	0x2C

#define AXI_I2S_RESET_GLOBAL	BIT(0)
#define AXI_I2S_RESET_TX_FIFO	BIT(1)
#define AXI_I2S_RESET_RX_FIFO	BIT(2)

#define AXI_I2S_CTRL_TX_EN	BIT(0)
#define AXI_I2S_CTRL_RX_EN	BIT(1)

/* The frame size is configurable, but for now we always set it 64 bit */
#define AXI_I2S_BITS_PER_FRAME 64

struct axi_i2s {
	struct regmap *regmap;
	struct clk *clk;
	struct clk *clk_ref;

	struct snd_soc_dai_driver dai_driver;

	struct snd_dmaengine_dai_dma_data capture_dma_data;
	struct snd_dmaengine_dai_dma_data playback_dma_data;

	struct snd_ratnum ratnum;
	struct snd_pcm_hw_constraint_ratnums rate_constraints;
};

static int axi_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
	struct snd_soc_dai *dai)
{
	struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
	unsigned int mask, val;

	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
		mask = AXI_I2S_CTRL_RX_EN;
	else
		mask = AXI_I2S_CTRL_TX_EN;

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
		val = mask;
		break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
		val = 0;
		break;
	default:
		return -EINVAL;
	}

	regmap_update_bits(i2s->regmap, AXI_I2S_REG_CTRL, mask, val);

	return 0;
}

static int axi_i2s_hw_params(struct snd_pcm_substream *substream,
	struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
{
	struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
	unsigned int bclk_div, word_size;
	unsigned int bclk_rate;

	bclk_rate = params_rate(params) * AXI_I2S_BITS_PER_FRAME;

	word_size = AXI_I2S_BITS_PER_FRAME / 2 - 1;
	bclk_div = DIV_ROUND_UP(clk_get_rate(i2s->clk_ref), bclk_rate) / 2 - 1;

	regmap_write(i2s->regmap, AXI_I2S_REG_CLK_CTRL, (word_size << 16) |
		bclk_div);

	return 0;
}

static int axi_i2s_startup(struct snd_pcm_substream *substream,
	struct snd_soc_dai *dai)
{
	struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
	uint32_t mask;
	int ret;

	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
		mask = AXI_I2S_RESET_RX_FIFO;
	else
		mask = AXI_I2S_RESET_TX_FIFO;

	regmap_write(i2s->regmap, AXI_I2S_REG_RESET, mask);

	ret = snd_pcm_hw_constraint_ratnums(substream->runtime, 0,
			   SNDRV_PCM_HW_PARAM_RATE,
			   &i2s->rate_constraints);
	if (ret)
		return ret;

	return clk_prepare_enable(i2s->clk_ref);
}

static void axi_i2s_shutdown(struct snd_pcm_substream *substream,
	struct snd_soc_dai *dai)
{
	struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);

	clk_disable_unprepare(i2s->clk_ref);
}

static int axi_i2s_dai_probe(struct snd_soc_dai *dai)
{
	struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);

	snd_soc_dai_init_dma_data(dai, &i2s->playback_dma_data,
		&i2s->capture_dma_data);

	return 0;
}

static const struct snd_soc_dai_ops axi_i2s_dai_ops = {
	.startup = axi_i2s_startup,
	.shutdown = axi_i2s_shutdown,
	.trigger = axi_i2s_trigger,
	.hw_params = axi_i2s_hw_params,
};

static struct snd_soc_dai_driver axi_i2s_dai = {
	.probe = axi_i2s_dai_probe,
	.playback = {
		.channels_min = 2,
		.channels_max = 2,
		.rates = SNDRV_PCM_RATE_KNOT,
		.formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE,
	},
	.capture = {
		.channels_min = 2,
		.channels_max = 2,
		.rates = SNDRV_PCM_RATE_KNOT,
		.formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE,
	},
	.ops = &axi_i2s_dai_ops,
	.symmetric_rates = 1,
};

static const struct snd_soc_component_driver axi_i2s_component = {
	.name = "axi-i2s",
};

static const struct regmap_config axi_i2s_regmap_config = {
	.reg_bits = 32,
	.reg_stride = 4,
	.val_bits = 32,
	.max_register = AXI_I2S_REG_STATUS,
};

static int axi_i2s_probe(struct platform_device *pdev)
{
	struct resource *res;
	struct axi_i2s *i2s;
	void __iomem *base;
	int ret;

	i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
	if (!i2s)
		return -ENOMEM;

	platform_set_drvdata(pdev, i2s);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(base))
		return PTR_ERR(base);

	i2s->regmap = devm_regmap_init_mmio(&pdev->dev, base,
		&axi_i2s_regmap_config);
	if (IS_ERR(i2s->regmap))
		return PTR_ERR(i2s->regmap);

	i2s->clk = devm_clk_get(&pdev->dev, "axi");
	if (IS_ERR(i2s->clk))
		return PTR_ERR(i2s->clk);

	i2s->clk_ref = devm_clk_get(&pdev->dev, "ref");
	if (IS_ERR(i2s->clk_ref))
		return PTR_ERR(i2s->clk_ref);

	ret = clk_prepare_enable(i2s->clk);
	if (ret)
		return ret;

	i2s->playback_dma_data.addr = res->start + AXI_I2S_REG_TX_FIFO;
	i2s->playback_dma_data.addr_width = 4;
	i2s->playback_dma_data.maxburst = 1;

	i2s->capture_dma_data.addr = res->start + AXI_I2S_REG_RX_FIFO;
	i2s->capture_dma_data.addr_width = 4;
	i2s->capture_dma_data.maxburst = 1;

	i2s->ratnum.num = clk_get_rate(i2s->clk_ref) / 2 / AXI_I2S_BITS_PER_FRAME;
	i2s->ratnum.den_step = 1;
	i2s->ratnum.den_min = 1;
	i2s->ratnum.den_max = 64;

	i2s->rate_constraints.rats = &i2s->ratnum;
	i2s->rate_constraints.nrats = 1;

	regmap_write(i2s->regmap, AXI_I2S_REG_RESET, AXI_I2S_RESET_GLOBAL);

	ret = devm_snd_soc_register_component(&pdev->dev, &axi_i2s_component,
					 &axi_i2s_dai, 1);
	if (ret)
		goto err_clk_disable;

	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
	if (ret)
		goto err_clk_disable;

	return 0;

err_clk_disable:
	clk_disable_unprepare(i2s->clk);
	return ret;
}

static int axi_i2s_dev_remove(struct platform_device *pdev)
{
	struct axi_i2s *i2s = platform_get_drvdata(pdev);

	clk_disable_unprepare(i2s->clk);

	return 0;
}

static const struct of_device_id axi_i2s_of_match[] = {
	{ .compatible = "adi,axi-i2s-1.00.a", },
	{},
};
MODULE_DEVICE_TABLE(of, axi_i2s_of_match);

static struct platform_driver axi_i2s_driver = {
	.driver = {
		.name = "axi-i2s",
		.of_match_table = axi_i2s_of_match,
	},
	.probe = axi_i2s_probe,
	.remove = axi_i2s_dev_remove,
};
module_platform_driver(axi_i2s_driver);

MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
MODULE_DESCRIPTION("AXI I2S driver");
MODULE_LICENSE("GPL");