1 /*
2 * Copyright (c) 2010-2011,2013-2015 The Linux Foundation. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 and
6 * only version 2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * storm.c -- ALSA SoC machine driver for QTi ipq806x-based Storm board
14 */
15
16 #include <linux/device.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/mod_devicetable.h>
20 #include <linux/platform_device.h>
21 #include <sound/pcm.h>
22 #include <sound/pcm_params.h>
23 #include <sound/soc.h>
24
25 #define STORM_SYSCLK_MULT 4
26
storm_ops_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params)27 static int storm_ops_hw_params(struct snd_pcm_substream *substream,
28 struct snd_pcm_hw_params *params)
29 {
30 struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
31 struct snd_soc_card *card = soc_runtime->card;
32 snd_pcm_format_t format = params_format(params);
33 unsigned int rate = params_rate(params);
34 unsigned int sysclk_freq;
35 int bitwidth, ret;
36
37 bitwidth = snd_pcm_format_width(format);
38 if (bitwidth < 0) {
39 dev_err(card->dev, "invalid bit width given: %d\n", bitwidth);
40 return bitwidth;
41 }
42
43 /*
44 * as the CPU DAI is the I2S bus master and no system clock is needed by
45 * the MAX98357a DAC, simply set the system clock to be a constant
46 * multiple of the bit clock for the clock divider
47 */
48 sysclk_freq = rate * bitwidth * 2 * STORM_SYSCLK_MULT;
49
50 ret = snd_soc_dai_set_sysclk(soc_runtime->cpu_dai, 0, sysclk_freq, 0);
51 if (ret) {
52 dev_err(card->dev, "error setting sysclk to %u: %d\n",
53 sysclk_freq, ret);
54 return ret;
55 }
56
57 return 0;
58 }
59
60 static const struct snd_soc_ops storm_soc_ops = {
61 .hw_params = storm_ops_hw_params,
62 };
63
64 static struct snd_soc_dai_link storm_dai_link = {
65 .name = "Primary",
66 .stream_name = "Primary",
67 .codec_dai_name = "HiFi",
68 .ops = &storm_soc_ops,
69 };
70
storm_parse_of(struct snd_soc_card * card)71 static int storm_parse_of(struct snd_soc_card *card)
72 {
73 struct snd_soc_dai_link *dai_link = card->dai_link;
74 struct device_node *np = card->dev->of_node;
75
76 dai_link->cpu_of_node = of_parse_phandle(np, "cpu", 0);
77 if (!dai_link->cpu_of_node) {
78 dev_err(card->dev, "error getting cpu phandle\n");
79 return -EINVAL;
80 }
81 dai_link->platform_of_node = dai_link->cpu_of_node;
82
83 dai_link->codec_of_node = of_parse_phandle(np, "codec", 0);
84 if (!dai_link->codec_of_node) {
85 dev_err(card->dev, "error getting codec phandle\n");
86 return -EINVAL;
87 }
88
89 return 0;
90 }
91
storm_platform_probe(struct platform_device * pdev)92 static int storm_platform_probe(struct platform_device *pdev)
93 {
94 struct snd_soc_card *card;
95 int ret;
96
97 card = devm_kzalloc(&pdev->dev, sizeof(*card), GFP_KERNEL);
98 if (!card)
99 return -ENOMEM;
100
101 card->dev = &pdev->dev;
102
103 ret = snd_soc_of_parse_card_name(card, "qcom,model");
104 if (ret) {
105 dev_err(&pdev->dev, "error parsing card name: %d\n", ret);
106 return ret;
107 }
108
109 card->dai_link = &storm_dai_link;
110 card->num_links = 1;
111
112 ret = storm_parse_of(card);
113 if (ret) {
114 dev_err(&pdev->dev, "error resolving dai links: %d\n", ret);
115 return ret;
116 }
117
118 ret = devm_snd_soc_register_card(&pdev->dev, card);
119 if (ret)
120 dev_err(&pdev->dev, "error registering soundcard: %d\n", ret);
121
122 return ret;
123
124 }
125
126 #ifdef CONFIG_OF
127 static const struct of_device_id storm_device_id[] = {
128 { .compatible = "google,storm-audio" },
129 {},
130 };
131 MODULE_DEVICE_TABLE(of, storm_device_id);
132 #endif
133
134 static struct platform_driver storm_platform_driver = {
135 .driver = {
136 .name = "storm-audio",
137 .of_match_table =
138 of_match_ptr(storm_device_id),
139 },
140 .probe = storm_platform_probe,
141 };
142 module_platform_driver(storm_platform_driver);
143
144 MODULE_DESCRIPTION("QTi IPQ806x-based Storm Machine Driver");
145 MODULE_LICENSE("GPL v2");
146
