storm.c

  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
 19static 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 = snd_soc_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(snd_soc_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
 52static const struct snd_soc_ops storm_soc_ops = {
 53	.hw_params	= storm_ops_hw_params,
 54};
 55
 56SND_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
 61static 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
 68static 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
 89static 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
125static const struct of_device_id storm_device_id[]  = {
126	{ .compatible = "google,storm-audio" },
127	{},
128};
129MODULE_DEVICE_TABLE(of, storm_device_id);
130#endif
131
132static 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};
140module_platform_driver(storm_platform_driver);
141
142MODULE_DESCRIPTION("QTi IPQ806x-based Storm Machine Driver");
143MODULE_LICENSE("GPL");