1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * tegra_pcm.c - Tegra PCM driver
4  *
5  * Author: Stephen Warren <swarren@nvidia.com>
6  * Copyright (C) 2010,2012 - NVIDIA, Inc.
7  *
8  * Based on code copyright/by:
9  *
10  * Copyright (c) 2009-2010, NVIDIA Corporation.
11  * Scott Peterson <speterson@nvidia.com>
12  * Vijay Mali <vmali@nvidia.com>
13  *
14  * Copyright (C) 2010 Google, Inc.
15  * Iliyan Malchev <malchev@google.com>
16  */
17 
18 #include <linux/module.h>
19 #include <linux/dma-mapping.h>
20 #include <sound/core.h>
21 #include <sound/pcm.h>
22 #include <sound/pcm_params.h>
23 #include <sound/soc.h>
24 #include <sound/dmaengine_pcm.h>
25 #include "tegra_pcm.h"
26 
27 static const struct snd_pcm_hardware tegra_pcm_hardware = {
28 	.info			= SNDRV_PCM_INFO_MMAP |
29 				  SNDRV_PCM_INFO_MMAP_VALID |
30 				  SNDRV_PCM_INFO_INTERLEAVED,
31 	.period_bytes_min	= 1024,
32 	.period_bytes_max	= PAGE_SIZE,
33 	.periods_min		= 2,
34 	.periods_max		= 8,
35 	.buffer_bytes_max	= PAGE_SIZE * 8,
36 	.fifo_size		= 4,
37 };
38 
39 static const struct snd_dmaengine_pcm_config tegra_dmaengine_pcm_config = {
40 	.pcm_hardware = &tegra_pcm_hardware,
41 	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
42 	.prealloc_buffer_size = PAGE_SIZE * 8,
43 };
44 
tegra_pcm_platform_register(struct device * dev)45 int tegra_pcm_platform_register(struct device *dev)
46 {
47 	return snd_dmaengine_pcm_register(dev, &tegra_dmaengine_pcm_config, 0);
48 }
49 EXPORT_SYMBOL_GPL(tegra_pcm_platform_register);
50 
devm_tegra_pcm_platform_register(struct device * dev)51 int devm_tegra_pcm_platform_register(struct device *dev)
52 {
53 	return devm_snd_dmaengine_pcm_register(dev, &tegra_dmaengine_pcm_config, 0);
54 }
55 EXPORT_SYMBOL_GPL(devm_tegra_pcm_platform_register);
56 
tegra_pcm_platform_register_with_chan_names(struct device * dev,struct snd_dmaengine_pcm_config * config,char * txdmachan,char * rxdmachan)57 int tegra_pcm_platform_register_with_chan_names(struct device *dev,
58 				struct snd_dmaengine_pcm_config *config,
59 				char *txdmachan, char *rxdmachan)
60 {
61 	*config = tegra_dmaengine_pcm_config;
62 	config->dma_dev = dev->parent;
63 	config->chan_names[0] = txdmachan;
64 	config->chan_names[1] = rxdmachan;
65 
66 	return snd_dmaengine_pcm_register(dev, config, 0);
67 }
68 EXPORT_SYMBOL_GPL(tegra_pcm_platform_register_with_chan_names);
69 
tegra_pcm_platform_unregister(struct device * dev)70 void tegra_pcm_platform_unregister(struct device *dev)
71 {
72 	return snd_dmaengine_pcm_unregister(dev);
73 }
74 EXPORT_SYMBOL_GPL(tegra_pcm_platform_unregister);
75 
tegra_pcm_open(struct snd_soc_component * component,struct snd_pcm_substream * substream)76 int tegra_pcm_open(struct snd_soc_component *component,
77 		   struct snd_pcm_substream *substream)
78 {
79 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
80 	struct snd_dmaengine_dai_dma_data *dmap;
81 	struct dma_chan *chan;
82 	struct snd_soc_dai *cpu_dai = asoc_rtd_to_cpu(rtd, 0);
83 	int ret;
84 
85 	if (rtd->dai_link->no_pcm)
86 		return 0;
87 
88 	dmap = snd_soc_dai_get_dma_data(cpu_dai, substream);
89 
90 	/* Set HW params now that initialization is complete */
91 	snd_soc_set_runtime_hwparams(substream, &tegra_pcm_hardware);
92 
93 	/* Ensure period size is multiple of 8 */
94 	ret = snd_pcm_hw_constraint_step(substream->runtime, 0,
95 					 SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 0x8);
96 	if (ret) {
97 		dev_err(rtd->dev, "failed to set constraint %d\n", ret);
98 		return ret;
99 	}
100 
101 	chan = dma_request_slave_channel(cpu_dai->dev, dmap->chan_name);
102 	if (!chan) {
103 		dev_err(cpu_dai->dev,
104 			"dmaengine request slave channel failed! (%s)\n",
105 			dmap->chan_name);
106 		return -ENODEV;
107 	}
108 
109 	ret = snd_dmaengine_pcm_open(substream, chan);
110 	if (ret) {
111 		dev_err(rtd->dev,
112 			"dmaengine pcm open failed with err %d (%s)\n", ret,
113 			dmap->chan_name);
114 
115 		dma_release_channel(chan);
116 
117 		return ret;
118 	}
119 
120 	return 0;
121 }
122 EXPORT_SYMBOL_GPL(tegra_pcm_open);
123 
tegra_pcm_close(struct snd_soc_component * component,struct snd_pcm_substream * substream)124 int tegra_pcm_close(struct snd_soc_component *component,
125 		    struct snd_pcm_substream *substream)
126 {
127 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
128 
129 	if (rtd->dai_link->no_pcm)
130 		return 0;
131 
132 	snd_dmaengine_pcm_close_release_chan(substream);
133 
134 	return 0;
135 }
136 EXPORT_SYMBOL_GPL(tegra_pcm_close);
137 
tegra_pcm_hw_params(struct snd_soc_component * component,struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params)138 int tegra_pcm_hw_params(struct snd_soc_component *component,
139 			struct snd_pcm_substream *substream,
140 			struct snd_pcm_hw_params *params)
141 {
142 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
143 	struct snd_dmaengine_dai_dma_data *dmap;
144 	struct dma_slave_config slave_config;
145 	struct dma_chan *chan;
146 	int ret;
147 
148 	if (rtd->dai_link->no_pcm)
149 		return 0;
150 
151 	dmap = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
152 	if (!dmap)
153 		return 0;
154 
155 	chan = snd_dmaengine_pcm_get_chan(substream);
156 
157 	ret = snd_hwparams_to_dma_slave_config(substream, params,
158 					       &slave_config);
159 	if (ret) {
160 		dev_err(rtd->dev, "hw params config failed with err %d\n", ret);
161 		return ret;
162 	}
163 
164 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
165 		slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
166 		slave_config.dst_addr = dmap->addr;
167 		slave_config.dst_maxburst = 8;
168 	} else {
169 		slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
170 		slave_config.src_addr = dmap->addr;
171 		slave_config.src_maxburst = 8;
172 	}
173 
174 	ret = dmaengine_slave_config(chan, &slave_config);
175 	if (ret < 0) {
176 		dev_err(rtd->dev, "dma slave config failed with err %d\n", ret);
177 		return ret;
178 	}
179 
180 	return 0;
181 }
182 EXPORT_SYMBOL_GPL(tegra_pcm_hw_params);
183 
tegra_pcm_pointer(struct snd_soc_component * component,struct snd_pcm_substream * substream)184 snd_pcm_uframes_t tegra_pcm_pointer(struct snd_soc_component *component,
185 				    struct snd_pcm_substream *substream)
186 {
187 	return snd_dmaengine_pcm_pointer(substream);
188 }
189 EXPORT_SYMBOL_GPL(tegra_pcm_pointer);
190 
tegra_pcm_dma_allocate(struct device * dev,struct snd_soc_pcm_runtime * rtd,size_t size)191 static int tegra_pcm_dma_allocate(struct device *dev, struct snd_soc_pcm_runtime *rtd,
192 				  size_t size)
193 {
194 	struct snd_pcm *pcm = rtd->pcm;
195 	int ret;
196 
197 	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
198 	if (ret < 0)
199 		return ret;
200 
201 	return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV_WC, dev, size);
202 }
203 
tegra_pcm_construct(struct snd_soc_component * component,struct snd_soc_pcm_runtime * rtd)204 int tegra_pcm_construct(struct snd_soc_component *component,
205 			struct snd_soc_pcm_runtime *rtd)
206 {
207 	struct device *dev = component->dev;
208 
209 	/*
210 	 * Fallback for backwards-compatibility with older device trees that
211 	 * have the iommus property in the virtual, top-level "sound" node.
212 	 */
213 	if (!of_get_property(dev->of_node, "iommus", NULL))
214 		dev = rtd->card->snd_card->dev;
215 
216 	return tegra_pcm_dma_allocate(dev, rtd, tegra_pcm_hardware.buffer_bytes_max);
217 }
218 EXPORT_SYMBOL_GPL(tegra_pcm_construct);
219 
220 MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");
221 MODULE_DESCRIPTION("Tegra PCM ASoC driver");
222 MODULE_LICENSE("GPL");
223