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
27static 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, "%s() invalid bit width given: %d\n",
40				__func__, bitwidth);
41		return bitwidth;
42	}
43
44	/*
45	 * as the CPU DAI is the I2S bus master and no system clock is needed by
46	 * the MAX98357a DAC, simply set the system clock to be a constant
47	 * multiple of the bit clock for the clock divider
48	 */
49	sysclk_freq = rate * bitwidth * 2 * STORM_SYSCLK_MULT;
50
51	ret = snd_soc_dai_set_sysclk(soc_runtime->cpu_dai, 0, sysclk_freq, 0);
52	if (ret) {
53		dev_err(card->dev, "%s() error setting sysclk to %u: %d\n",
54				__func__, sysclk_freq, ret);
55		return ret;
56	}
57
58	return 0;
59}
60
61static struct snd_soc_ops storm_soc_ops = {
62	.hw_params	= storm_ops_hw_params,
63};
64
65static struct snd_soc_dai_link storm_dai_link = {
66	.name		= "Primary",
67	.stream_name	= "Primary",
68	.codec_dai_name	= "HiFi",
69	.ops		= &storm_soc_ops,
70};
71
72static struct snd_soc_card storm_soc_card = {
73	.name	= "ipq806x-storm",
74	.dev	= NULL,
75};
76
77static int storm_parse_of(struct snd_soc_card *card)
78{
79	struct snd_soc_dai_link *dai_link = card->dai_link;
80	struct device_node *np = card->dev->of_node;
81
82	dai_link->cpu_of_node = of_parse_phandle(np, "cpu", 0);
83	if (!dai_link->cpu_of_node) {
84		dev_err(card->dev, "%s() error getting cpu phandle\n",
85				__func__);
86		return -EINVAL;
87	}
88	dai_link->platform_of_node = dai_link->cpu_of_node;
89
90	dai_link->codec_of_node = of_parse_phandle(np, "codec", 0);
91	if (!dai_link->codec_of_node) {
92		dev_err(card->dev, "%s() error getting codec phandle\n",
93				__func__);
94		return -EINVAL;
95	}
96
97	return 0;
98}
99
100static int storm_platform_probe(struct platform_device *pdev)
101{
102	struct snd_soc_card *card = &storm_soc_card;
103	int ret;
104
105	if (card->dev) {
106		dev_err(&pdev->dev, "%s() error, existing soundcard\n",
107				__func__);
108		return -ENODEV;
109	}
110	card->dev = &pdev->dev;
111	platform_set_drvdata(pdev, card);
112
113	ret = snd_soc_of_parse_card_name(card, "qcom,model");
114	if (ret) {
115		dev_err(&pdev->dev, "%s() error parsing card name: %d\n",
116				__func__, ret);
117		return ret;
118	}
119
120	card->dai_link	= &storm_dai_link;
121	card->num_links	= 1;
122
123	ret = storm_parse_of(card);
124	if (ret) {
125		dev_err(&pdev->dev, "%s() error resolving dai links: %d\n",
126				__func__, ret);
127		return ret;
128	}
129
130	ret = devm_snd_soc_register_card(&pdev->dev, card);
131	if (ret == -EPROBE_DEFER) {
132		card->dev = NULL;
133		return ret;
134	} else if (ret) {
135		dev_err(&pdev->dev, "%s() error registering soundcard: %d\n",
136				__func__, ret);
137		return ret;
138	}
139
140	return 0;
141}
142
143#ifdef CONFIG_OF
144static const struct of_device_id storm_device_id[]  = {
145	{ .compatible = "google,storm-audio" },
146	{},
147};
148MODULE_DEVICE_TABLE(of, storm_device_id);
149#endif
150
151static struct platform_driver storm_platform_driver = {
152	.driver = {
153		.name = "storm-audio",
154		.of_match_table =
155			of_match_ptr(storm_device_id),
156	},
157	.probe = storm_platform_probe,
158};
159module_platform_driver(storm_platform_driver);
160
161MODULE_DESCRIPTION("QTi IPQ806x-based Storm Machine Driver");
162MODULE_LICENSE("GPL v2");
163