1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2010-2011,2013-2015 The Linux Foundation. All rights reserved.
4  *
5  * storm.c -- ALSA SoC machine driver for QTi ipq806x-based Storm board
6  */
7 
8 #include <linux/device.h>
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/mod_devicetable.h>
12 #include <linux/platform_device.h>
13 #include <sound/pcm.h>
14 #include <sound/pcm_params.h>
15 #include <sound/soc.h>
16 
17 #define STORM_SYSCLK_MULT			4
18 
storm_ops_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params)19 static int storm_ops_hw_params(struct snd_pcm_substream *substream,
20 		struct snd_pcm_hw_params *params)
21 {
22 	struct snd_soc_pcm_runtime *soc_runtime = asoc_substream_to_rtd(substream);
23 	struct snd_soc_card *card = soc_runtime->card;
24 	snd_pcm_format_t format = params_format(params);
25 	unsigned int rate = params_rate(params);
26 	unsigned int sysclk_freq;
27 	int bitwidth, ret;
28 
29 	bitwidth = snd_pcm_format_width(format);
30 	if (bitwidth < 0) {
31 		dev_err(card->dev, "invalid bit width given: %d\n", bitwidth);
32 		return bitwidth;
33 	}
34 
35 	/*
36 	 * as the CPU DAI is the I2S bus master and no system clock is needed by
37 	 * the MAX98357a DAC, simply set the system clock to be a constant
38 	 * multiple of the bit clock for the clock divider
39 	 */
40 	sysclk_freq = rate * bitwidth * 2 * STORM_SYSCLK_MULT;
41 
42 	ret = snd_soc_dai_set_sysclk(asoc_rtd_to_cpu(soc_runtime, 0), 0, sysclk_freq, 0);
43 	if (ret) {
44 		dev_err(card->dev, "error setting sysclk to %u: %d\n",
45 			sysclk_freq, ret);
46 		return ret;
47 	}
48 
49 	return 0;
50 }
51 
52 static const struct snd_soc_ops storm_soc_ops = {
53 	.hw_params	= storm_ops_hw_params,
54 };
55 
56 SND_SOC_DAILINK_DEFS(hifi,
57 	DAILINK_COMP_ARRAY(COMP_EMPTY()),
58 	DAILINK_COMP_ARRAY(COMP_CODEC(NULL, "HiFi")),
59 	DAILINK_COMP_ARRAY(COMP_EMPTY()));
60 
61 static struct snd_soc_dai_link storm_dai_link = {
62 	.name		= "Primary",
63 	.stream_name	= "Primary",
64 	.ops		= &storm_soc_ops,
65 	SND_SOC_DAILINK_REG(hifi),
66 };
67 
storm_parse_of(struct snd_soc_card * card)68 static int storm_parse_of(struct snd_soc_card *card)
69 {
70 	struct snd_soc_dai_link *dai_link = card->dai_link;
71 	struct device_node *np = card->dev->of_node;
72 
73 	dai_link->cpus->of_node = of_parse_phandle(np, "cpu", 0);
74 	if (!dai_link->cpus->of_node) {
75 		dev_err(card->dev, "error getting cpu phandle\n");
76 		return -EINVAL;
77 	}
78 	dai_link->platforms->of_node = dai_link->cpus->of_node;
79 
80 	dai_link->codecs->of_node = of_parse_phandle(np, "codec", 0);
81 	if (!dai_link->codecs->of_node) {
82 		dev_err(card->dev, "error getting codec phandle\n");
83 		return -EINVAL;
84 	}
85 
86 	return 0;
87 }
88 
storm_platform_probe(struct platform_device * pdev)89 static int storm_platform_probe(struct platform_device *pdev)
90 {
91 	struct snd_soc_card *card;
92 	int ret;
93 
94 	card = devm_kzalloc(&pdev->dev, sizeof(*card), GFP_KERNEL);
95 	if (!card)
96 		return -ENOMEM;
97 
98 	card->dev = &pdev->dev;
99 	card->owner = THIS_MODULE;
100 
101 	ret = snd_soc_of_parse_card_name(card, "qcom,model");
102 	if (ret) {
103 		dev_err(&pdev->dev, "error parsing card name: %d\n", ret);
104 		return ret;
105 	}
106 
107 	card->dai_link	= &storm_dai_link;
108 	card->num_links	= 1;
109 
110 	ret = storm_parse_of(card);
111 	if (ret) {
112 		dev_err(&pdev->dev, "error resolving dai links: %d\n", ret);
113 		return ret;
114 	}
115 
116 	ret = devm_snd_soc_register_card(&pdev->dev, card);
117 	if (ret)
118 		dev_err(&pdev->dev, "error registering soundcard: %d\n", ret);
119 
120 	return ret;
121 
122 }
123 
124 #ifdef CONFIG_OF
125 static const struct of_device_id storm_device_id[]  = {
126 	{ .compatible = "google,storm-audio" },
127 	{},
128 };
129 MODULE_DEVICE_TABLE(of, storm_device_id);
130 #endif
131 
132 static struct platform_driver storm_platform_driver = {
133 	.driver = {
134 		.name = "storm-audio",
135 		.of_match_table =
136 			of_match_ptr(storm_device_id),
137 	},
138 	.probe = storm_platform_probe,
139 };
140 module_platform_driver(storm_platform_driver);
141 
142 MODULE_DESCRIPTION("QTi IPQ806x-based Storm Machine Driver");
143 MODULE_LICENSE("GPL v2");
144