xref: /linux/sound/soc/fsl/mpc5200_psc_i2s.c (revision 40d269c000bda9fcd276a0412a9cebd3f6e344c5)
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 
36 static 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  */
86 static 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  */
106 static 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  */
124 static 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 
130 static 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 
149 static 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  */
159 static 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 
212 static 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 */
219 static const struct of_device_id psc_i2s_match[] = {
220 	{ .compatible = "fsl,mpc5200-psc-i2s", },
221 	{ .compatible = "fsl,mpc5200b-psc-i2s", },
222 	{}
223 };
224 MODULE_DEVICE_TABLE(of, psc_i2s_match);
225 
226 static 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 
235 module_platform_driver(psc_i2s_driver);
236 
237 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
238 MODULE_DESCRIPTION("Freescale MPC5200 PSC in I2S mode ASoC Driver");
239 MODULE_LICENSE("GPL");
240 
241