xref: /openbmc/linux/sound/soc/meson/aiu-fifo-i2s.c (revision c29b9772)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (c) 2020 BayLibre, SAS.
4 // Author: Jerome Brunet <jbrunet@baylibre.com>
5 
6 #include <linux/bitfield.h>
7 #include <linux/clk.h>
8 #include <sound/pcm_params.h>
9 #include <sound/soc.h>
10 #include <sound/soc-dai.h>
11 
12 #include "aiu.h"
13 #include "aiu-fifo.h"
14 
15 #define AIU_I2S_SOURCE_DESC_MODE_8CH	BIT(0)
16 #define AIU_I2S_SOURCE_DESC_MODE_24BIT	BIT(5)
17 #define AIU_I2S_SOURCE_DESC_MODE_32BIT	BIT(9)
18 #define AIU_I2S_SOURCE_DESC_MODE_SPLIT	BIT(11)
19 #define AIU_MEM_I2S_MASKS_IRQ_BLOCK	GENMASK(31, 16)
20 #define AIU_MEM_I2S_CONTROL_MODE_16BIT	BIT(6)
21 #define AIU_MEM_I2S_BUF_CNTL_INIT	BIT(0)
22 #define AIU_RST_SOFT_I2S_FAST		BIT(0)
23 #define AIU_I2S_MISC_HOLD_EN		BIT(2)
24 #define AIU_I2S_MISC_FORCE_LEFT_RIGHT	BIT(4)
25 
26 #define AIU_FIFO_I2S_BLOCK		256
27 
28 static struct snd_pcm_hardware fifo_i2s_pcm = {
29 	.info = (SNDRV_PCM_INFO_INTERLEAVED |
30 		 SNDRV_PCM_INFO_MMAP |
31 		 SNDRV_PCM_INFO_MMAP_VALID |
32 		 SNDRV_PCM_INFO_PAUSE),
33 	.formats = AIU_FORMATS,
34 	.rate_min = 5512,
35 	.rate_max = 192000,
36 	.channels_min = 2,
37 	.channels_max = 8,
38 	.period_bytes_min = AIU_FIFO_I2S_BLOCK,
39 	.period_bytes_max = AIU_FIFO_I2S_BLOCK * USHRT_MAX,
40 	.periods_min = 2,
41 	.periods_max = UINT_MAX,
42 
43 	/* No real justification for this */
44 	.buffer_bytes_max = 1 * 1024 * 1024,
45 };
46 
47 static int aiu_fifo_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
48 				struct snd_soc_dai *dai)
49 {
50 	struct snd_soc_component *component = dai->component;
51 
52 	switch (cmd) {
53 	case SNDRV_PCM_TRIGGER_START:
54 	case SNDRV_PCM_TRIGGER_RESUME:
55 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
56 		snd_soc_component_write(component, AIU_RST_SOFT,
57 					AIU_RST_SOFT_I2S_FAST);
58 		snd_soc_component_read(component, AIU_I2S_SYNC);
59 		break;
60 	}
61 
62 	return aiu_fifo_trigger(substream, cmd, dai);
63 }
64 
65 static int aiu_fifo_i2s_prepare(struct snd_pcm_substream *substream,
66 				struct snd_soc_dai *dai)
67 {
68 	struct snd_soc_component *component = dai->component;
69 	int ret;
70 
71 	ret = aiu_fifo_prepare(substream, dai);
72 	if (ret)
73 		return ret;
74 
75 	snd_soc_component_update_bits(component,
76 				      AIU_MEM_I2S_BUF_CNTL,
77 				      AIU_MEM_I2S_BUF_CNTL_INIT,
78 				      AIU_MEM_I2S_BUF_CNTL_INIT);
79 	snd_soc_component_update_bits(component,
80 				      AIU_MEM_I2S_BUF_CNTL,
81 				      AIU_MEM_I2S_BUF_CNTL_INIT, 0);
82 
83 	return 0;
84 }
85 
86 static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream,
87 				  struct snd_pcm_hw_params *params,
88 				  struct snd_soc_dai *dai)
89 {
90 	struct snd_soc_component *component = dai->component;
91 	struct aiu_fifo *fifo = snd_soc_dai_dma_data_get_playback(dai);
92 	unsigned int val;
93 	int ret;
94 
95 	snd_soc_component_update_bits(component, AIU_I2S_MISC,
96 				      AIU_I2S_MISC_HOLD_EN,
97 				      AIU_I2S_MISC_HOLD_EN);
98 
99 	ret = aiu_fifo_hw_params(substream, params, dai);
100 	if (ret)
101 		return ret;
102 
103 	switch (params_physical_width(params)) {
104 	case 16:
105 		val = AIU_MEM_I2S_CONTROL_MODE_16BIT;
106 		break;
107 	case 32:
108 		val = 0;
109 		break;
110 	default:
111 		dev_err(dai->dev, "Unsupported physical width %u\n",
112 			params_physical_width(params));
113 		return -EINVAL;
114 	}
115 
116 	snd_soc_component_update_bits(component, AIU_MEM_I2S_CONTROL,
117 				      AIU_MEM_I2S_CONTROL_MODE_16BIT,
118 				      val);
119 
120 	/* Setup the irq periodicity */
121 	val = params_period_bytes(params) / fifo->fifo_block;
122 	val = FIELD_PREP(AIU_MEM_I2S_MASKS_IRQ_BLOCK, val);
123 	snd_soc_component_update_bits(component, AIU_MEM_I2S_MASKS,
124 				      AIU_MEM_I2S_MASKS_IRQ_BLOCK, val);
125 
126 	/*
127 	 * Most (all?) supported SoCs have this bit set by default. The vendor
128 	 * driver however sets it manually (depending on the version either
129 	 * while un-setting AIU_I2S_MISC_HOLD_EN or right before that). Follow
130 	 * the same approach for consistency with the vendor driver.
131 	 */
132 	snd_soc_component_update_bits(component, AIU_I2S_MISC,
133 				      AIU_I2S_MISC_FORCE_LEFT_RIGHT,
134 				      AIU_I2S_MISC_FORCE_LEFT_RIGHT);
135 
136 	snd_soc_component_update_bits(component, AIU_I2S_MISC,
137 				      AIU_I2S_MISC_HOLD_EN, 0);
138 
139 	return 0;
140 }
141 
142 const struct snd_soc_dai_ops aiu_fifo_i2s_dai_ops = {
143 	.trigger	= aiu_fifo_i2s_trigger,
144 	.prepare	= aiu_fifo_i2s_prepare,
145 	.hw_params	= aiu_fifo_i2s_hw_params,
146 	.startup	= aiu_fifo_startup,
147 	.shutdown	= aiu_fifo_shutdown,
148 };
149 
150 int aiu_fifo_i2s_dai_probe(struct snd_soc_dai *dai)
151 {
152 	struct snd_soc_component *component = dai->component;
153 	struct aiu *aiu = snd_soc_component_get_drvdata(component);
154 	struct aiu_fifo *fifo;
155 	int ret;
156 
157 	ret = aiu_fifo_dai_probe(dai);
158 	if (ret)
159 		return ret;
160 
161 	fifo = snd_soc_dai_dma_data_get_playback(dai);
162 
163 	fifo->pcm = &fifo_i2s_pcm;
164 	fifo->mem_offset = AIU_MEM_I2S_START;
165 	fifo->fifo_block = AIU_FIFO_I2S_BLOCK;
166 	fifo->pclk = aiu->i2s.clks[PCLK].clk;
167 	fifo->irq = aiu->i2s.irq;
168 
169 	return 0;
170 }
171