1// SPDX-License-Identifier: GPL-2.0-only
2//
3// tegra_audio_graph_card.c - Audio Graph based Tegra Machine Driver
4//
5// Copyright (c) 2020-2021 NVIDIA CORPORATION.  All rights reserved.
6
7#include <linux/math64.h>
8#include <linux/module.h>
9#include <linux/of_device.h>
10#include <linux/platform_device.h>
11#include <sound/graph_card.h>
12#include <sound/pcm_params.h>
13#include <sound/soc-dai.h>
14
15#define MAX_PLLA_OUT0_DIV 128
16
17#define simple_to_tegra_priv(simple) \
18		container_of(simple, struct tegra_audio_priv, simple)
19
20enum srate_type {
21	/*
22	 * Sample rates multiple of 8000 Hz and below are supported:
23	 * ( 8000, 16000, 32000, 48000, 96000, 192000 Hz )
24	 */
25	x8_RATE,
26
27	/*
28	 * Sample rates multiple of 11025 Hz and below are supported:
29	 * ( 11025, 22050, 44100, 88200, 176400 Hz )
30	 */
31	x11_RATE,
32
33	NUM_RATE_TYPE,
34};
35
36struct tegra_audio_priv {
37	struct asoc_simple_priv simple;
38	struct clk *clk_plla_out0;
39	struct clk *clk_plla;
40};
41
42/* Tegra audio chip data */
43struct tegra_audio_cdata {
44	unsigned int plla_rates[NUM_RATE_TYPE];
45	unsigned int plla_out0_rates[NUM_RATE_TYPE];
46};
47
48static bool need_clk_update(struct snd_soc_dai *dai)
49{
50	if (snd_soc_dai_is_dummy(dai) ||
51	    !dai->driver->ops ||
52	    !dai->driver->name)
53		return false;
54
55	if (strstr(dai->driver->name, "I2S") ||
56	    strstr(dai->driver->name, "DMIC") ||
57	    strstr(dai->driver->name, "DSPK"))
58		return true;
59
60	return false;
61}
62
63/* Setup PLL clock as per the given sample rate */
64static int tegra_audio_graph_update_pll(struct snd_pcm_substream *substream,
65					struct snd_pcm_hw_params *params)
66{
67	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
68	struct asoc_simple_priv *simple = snd_soc_card_get_drvdata(rtd->card);
69	struct tegra_audio_priv *priv = simple_to_tegra_priv(simple);
70	struct device *dev = rtd->card->dev;
71	const struct tegra_audio_cdata *data = of_device_get_match_data(dev);
72	unsigned int plla_rate, plla_out0_rate, bclk;
73	unsigned int srate = params_rate(params);
74	int err;
75
76	switch (srate) {
77	case 11025:
78	case 22050:
79	case 44100:
80	case 88200:
81	case 176400:
82		plla_out0_rate = data->plla_out0_rates[x11_RATE];
83		plla_rate = data->plla_rates[x11_RATE];
84		break;
85	case 8000:
86	case 16000:
87	case 32000:
88	case 48000:
89	case 96000:
90	case 192000:
91		plla_out0_rate = data->plla_out0_rates[x8_RATE];
92		plla_rate = data->plla_rates[x8_RATE];
93		break;
94	default:
95		dev_err(rtd->card->dev, "Unsupported sample rate %u\n",
96			srate);
97		return -EINVAL;
98	}
99
100	/*
101	 * Below is the clock relation:
102	 *
103	 *	PLLA
104	 *	  |
105	 *	  |--> PLLA_OUT0
106	 *		  |
107	 *		  |---> I2S modules
108	 *		  |
109	 *		  |---> DMIC modules
110	 *		  |
111	 *		  |---> DSPK modules
112	 *
113	 *
114	 * Default PLLA_OUT0 rate might be too high when I/O is running
115	 * at minimum PCM configurations. This may result in incorrect
116	 * clock rates and glitchy audio. The maximum divider is 128
117	 * and any thing higher than that won't work. Thus reduce PLLA_OUT0
118	 * to work for lower configurations.
119	 *
120	 * This problem is seen for I2S only, as DMIC and DSPK minimum
121	 * clock requirements are under allowed divider limits.
122	 */
123	bclk = srate * params_channels(params) * params_width(params);
124	if (div_u64(plla_out0_rate, bclk) > MAX_PLLA_OUT0_DIV)
125		plla_out0_rate >>= 1;
126
127	dev_dbg(rtd->card->dev,
128		"Update clock rates: PLLA(= %u Hz) and PLLA_OUT0(= %u Hz)\n",
129		plla_rate, plla_out0_rate);
130
131	/* Set PLLA rate */
132	err = clk_set_rate(priv->clk_plla, plla_rate);
133	if (err) {
134		dev_err(rtd->card->dev,
135			"Can't set plla rate for %u, err: %d\n",
136			plla_rate, err);
137		return err;
138	}
139
140	/* Set PLLA_OUT0 rate */
141	err = clk_set_rate(priv->clk_plla_out0, plla_out0_rate);
142	if (err) {
143		dev_err(rtd->card->dev,
144			"Can't set plla_out0 rate %u, err: %d\n",
145			plla_out0_rate, err);
146		return err;
147	}
148
149	return err;
150}
151
152static int tegra_audio_graph_hw_params(struct snd_pcm_substream *substream,
153				       struct snd_pcm_hw_params *params)
154{
155	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
156	struct snd_soc_dai *cpu_dai = asoc_rtd_to_cpu(rtd, 0);
157	int err;
158
159	if (need_clk_update(cpu_dai)) {
160		err = tegra_audio_graph_update_pll(substream, params);
161		if (err)
162			return err;
163	}
164
165	return asoc_simple_hw_params(substream, params);
166}
167
168static const struct snd_soc_ops tegra_audio_graph_ops = {
169	.startup	= asoc_simple_startup,
170	.shutdown	= asoc_simple_shutdown,
171	.hw_params	= tegra_audio_graph_hw_params,
172};
173
174static int tegra_audio_graph_card_probe(struct snd_soc_card *card)
175{
176	struct asoc_simple_priv *simple = snd_soc_card_get_drvdata(card);
177	struct tegra_audio_priv *priv = simple_to_tegra_priv(simple);
178
179	priv->clk_plla = devm_clk_get(card->dev, "pll_a");
180	if (IS_ERR(priv->clk_plla)) {
181		dev_err(card->dev, "Can't retrieve clk pll_a\n");
182		return PTR_ERR(priv->clk_plla);
183	}
184
185	priv->clk_plla_out0 = devm_clk_get(card->dev, "plla_out0");
186	if (IS_ERR(priv->clk_plla_out0)) {
187		dev_err(card->dev, "Can't retrieve clk plla_out0\n");
188		return PTR_ERR(priv->clk_plla_out0);
189	}
190
191	return asoc_graph_card_probe(card);
192}
193
194static int tegra_audio_graph_probe(struct platform_device *pdev)
195{
196	struct tegra_audio_priv *priv;
197	struct device *dev = &pdev->dev;
198	struct snd_soc_card *card;
199
200	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
201	if (!priv)
202		return -ENOMEM;
203
204	card = simple_priv_to_card(&priv->simple);
205	card->driver_name = "tegra-ape";
206
207	card->probe = tegra_audio_graph_card_probe;
208
209	/* audio_graph_parse_of() depends on below */
210	card->component_chaining = 1;
211	priv->simple.ops = &tegra_audio_graph_ops;
212	priv->simple.force_dpcm = 1;
213
214	return audio_graph_parse_of(&priv->simple, dev);
215}
216
217static const struct tegra_audio_cdata tegra210_data = {
218	/* PLLA */
219	.plla_rates[x8_RATE] = 368640000,
220	.plla_rates[x11_RATE] = 338688000,
221	/* PLLA_OUT0 */
222	.plla_out0_rates[x8_RATE] = 49152000,
223	.plla_out0_rates[x11_RATE] = 45158400,
224};
225
226static const struct tegra_audio_cdata tegra186_data = {
227	/* PLLA */
228	.plla_rates[x8_RATE] = 245760000,
229	.plla_rates[x11_RATE] = 270950400,
230	/* PLLA_OUT0 */
231	.plla_out0_rates[x8_RATE] = 49152000,
232	.plla_out0_rates[x11_RATE] = 45158400,
233};
234
235static const struct of_device_id graph_of_tegra_match[] = {
236	{ .compatible = "nvidia,tegra210-audio-graph-card",
237	  .data = &tegra210_data },
238	{ .compatible = "nvidia,tegra186-audio-graph-card",
239	  .data = &tegra186_data },
240	{},
241};
242MODULE_DEVICE_TABLE(of, graph_of_tegra_match);
243
244static struct platform_driver tegra_audio_graph_card = {
245	.driver = {
246		.name = "tegra-audio-graph-card",
247		.pm = &snd_soc_pm_ops,
248		.of_match_table = graph_of_tegra_match,
249	},
250	.probe = tegra_audio_graph_probe,
251	.remove = asoc_simple_remove,
252};
253module_platform_driver(tegra_audio_graph_card);
254
255MODULE_LICENSE("GPL v2");
256MODULE_DESCRIPTION("ASoC Tegra Audio Graph Sound Card");
257MODULE_AUTHOR("Sameer Pujar <spujar@nvidia.com>");
258