1// SPDX-License-Identifier: GPL-2.0-only
2//
3// Freescale MPC5200 PSC in I2S mode
4// ALSA SoC Digital Audio Interface (DAI) driver
5//
6// Copyright (C) 2008 Secret Lab Technologies Ltd.
7// Copyright (C) 2009 Jon Smirl, Digispeaker
8
9#include <linux/module.h>
10#include <linux/of.h>
11
12#include <sound/pcm.h>
13#include <sound/pcm_params.h>
14#include <sound/soc.h>
15
16#include <asm/mpc52xx_psc.h>
17
18#include "mpc5200_dma.h"
19
20/**
21 * PSC_I2S_RATES: sample rates supported by the I2S
22 *
23 * This driver currently only supports the PSC running in I2S slave mode,
24 * which means the codec determines the sample rate.  Therefore, we tell
25 * ALSA that we support all rates and let the codec driver decide what rates
26 * are really supported.
27 */
28#define PSC_I2S_RATES SNDRV_PCM_RATE_CONTINUOUS
29
30/**
31 * PSC_I2S_FORMATS: audio formats supported by the PSC I2S mode
32 */
33#define PSC_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | \
34			 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE)
35
36static int psc_i2s_hw_params(struct snd_pcm_substream *substream,
37				 struct snd_pcm_hw_params *params,
38				 struct snd_soc_dai *dai)
39{
40	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
41	struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));
42	u32 mode;
43
44	dev_dbg(psc_dma->dev, "%s(substream=%p) p_size=%i p_bytes=%i"
45		" periods=%i buffer_size=%i  buffer_bytes=%i\n",
46		__func__, substream, params_period_size(params),
47		params_period_bytes(params), params_periods(params),
48		params_buffer_size(params), params_buffer_bytes(params));
49
50	switch (params_format(params)) {
51	case SNDRV_PCM_FORMAT_S8:
52		mode = MPC52xx_PSC_SICR_SIM_CODEC_8;
53		break;
54	case SNDRV_PCM_FORMAT_S16_BE:
55		mode = MPC52xx_PSC_SICR_SIM_CODEC_16;
56		break;
57	case SNDRV_PCM_FORMAT_S24_BE:
58		mode = MPC52xx_PSC_SICR_SIM_CODEC_24;
59		break;
60	case SNDRV_PCM_FORMAT_S32_BE:
61		mode = MPC52xx_PSC_SICR_SIM_CODEC_32;
62		break;
63	default:
64		dev_dbg(psc_dma->dev, "invalid format\n");
65		return -EINVAL;
66	}
67	out_be32(&psc_dma->psc_regs->sicr, psc_dma->sicr | mode);
68
69	return 0;
70}
71
72/**
73 * psc_i2s_set_sysclk: set the clock frequency and direction
74 *
75 * This function is called by the machine driver to tell us what the clock
76 * frequency and direction are.
77 *
78 * Currently, we only support operating as a clock slave (SND_SOC_CLOCK_IN),
79 * and we don't care about the frequency.  Return an error if the direction
80 * is not SND_SOC_CLOCK_IN.
81 *
82 * @clk_id: reserved, should be zero
83 * @freq: the frequency of the given clock ID, currently ignored
84 * @dir: SND_SOC_CLOCK_IN (clock slave) or SND_SOC_CLOCK_OUT (clock master)
85 */
86static int psc_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
87			      int clk_id, unsigned int freq, int dir)
88{
89	struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(cpu_dai);
90	dev_dbg(psc_dma->dev, "psc_i2s_set_sysclk(cpu_dai=%p, dir=%i)\n",
91				cpu_dai, dir);
92	return (dir == SND_SOC_CLOCK_IN) ? 0 : -EINVAL;
93}
94
95/**
96 * psc_i2s_set_fmt: set the serial format.
97 *
98 * This function is called by the machine driver to tell us what serial
99 * format to use.
100 *
101 * This driver only supports I2S mode.  Return an error if the format is
102 * not SND_SOC_DAIFMT_I2S.
103 *
104 * @format: one of SND_SOC_DAIFMT_xxx
105 */
106static int psc_i2s_set_fmt(struct snd_soc_dai *cpu_dai, unsigned int format)
107{
108	struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(cpu_dai);
109	dev_dbg(psc_dma->dev, "psc_i2s_set_fmt(cpu_dai=%p, format=%i)\n",
110				cpu_dai, format);
111	return (format == SND_SOC_DAIFMT_I2S) ? 0 : -EINVAL;
112}
113
114/* ---------------------------------------------------------------------
115 * ALSA SoC Bindings
116 *
117 * - Digital Audio Interface (DAI) template
118 * - create/destroy dai hooks
119 */
120
121/**
122 * psc_i2s_dai_template: template CPU Digital Audio Interface
123 */
124static const struct snd_soc_dai_ops psc_i2s_dai_ops = {
125	.hw_params	= psc_i2s_hw_params,
126	.set_sysclk	= psc_i2s_set_sysclk,
127	.set_fmt	= psc_i2s_set_fmt,
128};
129
130static struct snd_soc_dai_driver psc_i2s_dai[] = {{
131	.name = "mpc5200-psc-i2s.0",
132	.playback = {
133		.stream_name = "I2S Playback",
134		.channels_min = 2,
135		.channels_max = 2,
136		.rates = PSC_I2S_RATES,
137		.formats = PSC_I2S_FORMATS,
138	},
139	.capture = {
140		.stream_name = "I2S Capture",
141		.channels_min = 2,
142		.channels_max = 2,
143		.rates = PSC_I2S_RATES,
144		.formats = PSC_I2S_FORMATS,
145	},
146	.ops = &psc_i2s_dai_ops,
147} };
148
149static const struct snd_soc_component_driver psc_i2s_component = {
150	.name			= "mpc5200-i2s",
151	.legacy_dai_naming	= 1,
152};
153
154/* ---------------------------------------------------------------------
155 * OF platform bus binding code:
156 * - Probe/remove operations
157 * - OF device match table
158 */
159static int psc_i2s_of_probe(struct platform_device *op)
160{
161	int rc;
162	struct psc_dma *psc_dma;
163	struct mpc52xx_psc __iomem *regs;
164
165	rc = mpc5200_audio_dma_create(op);
166	if (rc != 0)
167		return rc;
168
169	rc = snd_soc_register_component(&op->dev, &psc_i2s_component,
170					psc_i2s_dai, ARRAY_SIZE(psc_i2s_dai));
171	if (rc != 0) {
172		pr_err("Failed to register DAI\n");
173		return rc;
174	}
175
176	psc_dma = dev_get_drvdata(&op->dev);
177	regs = psc_dma->psc_regs;
178
179	/* Configure the serial interface mode; defaulting to CODEC8 mode */
180	psc_dma->sicr = MPC52xx_PSC_SICR_DTS1 | MPC52xx_PSC_SICR_I2S |
181			MPC52xx_PSC_SICR_CLKPOL;
182	out_be32(&psc_dma->psc_regs->sicr,
183		 psc_dma->sicr | MPC52xx_PSC_SICR_SIM_CODEC_8);
184
185	/* Check for the codec handle.  If it is not present then we
186	 * are done */
187	if (!of_get_property(op->dev.of_node, "codec-handle", NULL))
188		return 0;
189
190	/* Due to errata in the dma mode; need to line up enabling
191	 * the transmitter with a transition on the frame sync
192	 * line */
193
194	/* first make sure it is low */
195	while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) != 0)
196		;
197	/* then wait for the transition to high */
198	while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) == 0)
199		;
200	/* Finally, enable the PSC.
201	 * Receiver must always be enabled; even when we only want
202	 * transmit.  (see 15.3.2.3 of MPC5200B User's Guide) */
203
204	/* Go */
205	out_8(&psc_dma->psc_regs->command,
206			MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
207
208	return 0;
209
210}
211
212static void psc_i2s_of_remove(struct platform_device *op)
213{
214	mpc5200_audio_dma_destroy(op);
215	snd_soc_unregister_component(&op->dev);
216}
217
218/* Match table for of_platform binding */
219static const struct of_device_id psc_i2s_match[] = {
220	{ .compatible = "fsl,mpc5200-psc-i2s", },
221	{ .compatible = "fsl,mpc5200b-psc-i2s", },
222	{}
223};
224MODULE_DEVICE_TABLE(of, psc_i2s_match);
225
226static struct platform_driver psc_i2s_driver = {
227	.probe = psc_i2s_of_probe,
228	.remove_new = psc_i2s_of_remove,
229	.driver = {
230		.name = "mpc5200-psc-i2s",
231		.of_match_table = psc_i2s_match,
232	},
233};
234
235module_platform_driver(psc_i2s_driver);
236
237MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
238MODULE_DESCRIPTION("Freescale MPC5200 PSC in I2S mode ASoC Driver");
239MODULE_LICENSE("GPL");
240
241