xref: /openbmc/linux/sound/soc/fsl/mpc5200_psc_i2s.c (revision 12eb4683)
1 /*
2  * Freescale MPC5200 PSC in I2S mode
3  * ALSA SoC Digital Audio Interface (DAI) driver
4  *
5  * Copyright (C) 2008 Secret Lab Technologies Ltd.
6  * Copyright (C) 2009 Jon Smirl, Digispeaker
7  */
8 
9 #include <linux/module.h>
10 #include <linux/of_device.h>
11 #include <linux/of_platform.h>
12 
13 #include <sound/pcm.h>
14 #include <sound/pcm_params.h>
15 #include <sound/soc.h>
16 
17 #include <asm/mpc52xx_psc.h>
18 
19 #include "mpc5200_dma.h"
20 
21 /**
22  * PSC_I2S_RATES: sample rates supported by the I2S
23  *
24  * This driver currently only supports the PSC running in I2S slave mode,
25  * which means the codec determines the sample rate.  Therefore, we tell
26  * ALSA that we support all rates and let the codec driver decide what rates
27  * are really supported.
28  */
29 #define PSC_I2S_RATES (SNDRV_PCM_RATE_5512 | SNDRV_PCM_RATE_8000_192000 | \
30 			SNDRV_PCM_RATE_CONTINUOUS)
31 
32 /**
33  * PSC_I2S_FORMATS: audio formats supported by the PSC I2S mode
34  */
35 #define PSC_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | \
36 			 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE)
37 
38 static int psc_i2s_hw_params(struct snd_pcm_substream *substream,
39 				 struct snd_pcm_hw_params *params,
40 				 struct snd_soc_dai *dai)
41 {
42 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
43 	struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai);
44 	u32 mode;
45 
46 	dev_dbg(psc_dma->dev, "%s(substream=%p) p_size=%i p_bytes=%i"
47 		" periods=%i buffer_size=%i  buffer_bytes=%i\n",
48 		__func__, substream, params_period_size(params),
49 		params_period_bytes(params), params_periods(params),
50 		params_buffer_size(params), params_buffer_bytes(params));
51 
52 	switch (params_format(params)) {
53 	case SNDRV_PCM_FORMAT_S8:
54 		mode = MPC52xx_PSC_SICR_SIM_CODEC_8;
55 		break;
56 	case SNDRV_PCM_FORMAT_S16_BE:
57 		mode = MPC52xx_PSC_SICR_SIM_CODEC_16;
58 		break;
59 	case SNDRV_PCM_FORMAT_S24_BE:
60 		mode = MPC52xx_PSC_SICR_SIM_CODEC_24;
61 		break;
62 	case SNDRV_PCM_FORMAT_S32_BE:
63 		mode = MPC52xx_PSC_SICR_SIM_CODEC_32;
64 		break;
65 	default:
66 		dev_dbg(psc_dma->dev, "invalid format\n");
67 		return -EINVAL;
68 	}
69 	out_be32(&psc_dma->psc_regs->sicr, psc_dma->sicr | mode);
70 
71 	return 0;
72 }
73 
74 /**
75  * psc_i2s_set_sysclk: set the clock frequency and direction
76  *
77  * This function is called by the machine driver to tell us what the clock
78  * frequency and direction are.
79  *
80  * Currently, we only support operating as a clock slave (SND_SOC_CLOCK_IN),
81  * and we don't care about the frequency.  Return an error if the direction
82  * is not SND_SOC_CLOCK_IN.
83  *
84  * @clk_id: reserved, should be zero
85  * @freq: the frequency of the given clock ID, currently ignored
86  * @dir: SND_SOC_CLOCK_IN (clock slave) or SND_SOC_CLOCK_OUT (clock master)
87  */
88 static int psc_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
89 			      int clk_id, unsigned int freq, int dir)
90 {
91 	struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(cpu_dai);
92 	dev_dbg(psc_dma->dev, "psc_i2s_set_sysclk(cpu_dai=%p, dir=%i)\n",
93 				cpu_dai, dir);
94 	return (dir == SND_SOC_CLOCK_IN) ? 0 : -EINVAL;
95 }
96 
97 /**
98  * psc_i2s_set_fmt: set the serial format.
99  *
100  * This function is called by the machine driver to tell us what serial
101  * format to use.
102  *
103  * This driver only supports I2S mode.  Return an error if the format is
104  * not SND_SOC_DAIFMT_I2S.
105  *
106  * @format: one of SND_SOC_DAIFMT_xxx
107  */
108 static int psc_i2s_set_fmt(struct snd_soc_dai *cpu_dai, unsigned int format)
109 {
110 	struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(cpu_dai);
111 	dev_dbg(psc_dma->dev, "psc_i2s_set_fmt(cpu_dai=%p, format=%i)\n",
112 				cpu_dai, format);
113 	return (format == SND_SOC_DAIFMT_I2S) ? 0 : -EINVAL;
114 }
115 
116 /* ---------------------------------------------------------------------
117  * ALSA SoC Bindings
118  *
119  * - Digital Audio Interface (DAI) template
120  * - create/destroy dai hooks
121  */
122 
123 /**
124  * psc_i2s_dai_template: template CPU Digital Audio Interface
125  */
126 static const struct snd_soc_dai_ops psc_i2s_dai_ops = {
127 	.hw_params	= psc_i2s_hw_params,
128 	.set_sysclk	= psc_i2s_set_sysclk,
129 	.set_fmt	= psc_i2s_set_fmt,
130 };
131 
132 static struct snd_soc_dai_driver psc_i2s_dai[] = {{
133 	.name = "mpc5200-psc-i2s.0",
134 	.playback = {
135 		.stream_name = "I2S Playback",
136 		.channels_min = 2,
137 		.channels_max = 2,
138 		.rates = PSC_I2S_RATES,
139 		.formats = PSC_I2S_FORMATS,
140 	},
141 	.capture = {
142 		.stream_name = "I2S Capture",
143 		.channels_min = 2,
144 		.channels_max = 2,
145 		.rates = PSC_I2S_RATES,
146 		.formats = PSC_I2S_FORMATS,
147 	},
148 	.ops = &psc_i2s_dai_ops,
149 } };
150 
151 static const struct snd_soc_component_driver psc_i2s_component = {
152 	.name		= "mpc5200-i2s",
153 };
154 
155 /* ---------------------------------------------------------------------
156  * OF platform bus binding code:
157  * - Probe/remove operations
158  * - OF device match table
159  */
160 static int psc_i2s_of_probe(struct platform_device *op)
161 {
162 	int rc;
163 	struct psc_dma *psc_dma;
164 	struct mpc52xx_psc __iomem *regs;
165 
166 	rc = mpc5200_audio_dma_create(op);
167 	if (rc != 0)
168 		return rc;
169 
170 	rc = snd_soc_register_component(&op->dev, &psc_i2s_component,
171 					psc_i2s_dai, ARRAY_SIZE(psc_i2s_dai));
172 	if (rc != 0) {
173 		pr_err("Failed to register DAI\n");
174 		return rc;
175 	}
176 
177 	psc_dma = dev_get_drvdata(&op->dev);
178 	regs = psc_dma->psc_regs;
179 
180 	/* Configure the serial interface mode; defaulting to CODEC8 mode */
181 	psc_dma->sicr = MPC52xx_PSC_SICR_DTS1 | MPC52xx_PSC_SICR_I2S |
182 			MPC52xx_PSC_SICR_CLKPOL;
183 	out_be32(&psc_dma->psc_regs->sicr,
184 		 psc_dma->sicr | MPC52xx_PSC_SICR_SIM_CODEC_8);
185 
186 	/* Check for the codec handle.  If it is not present then we
187 	 * are done */
188 	if (!of_get_property(op->dev.of_node, "codec-handle", NULL))
189 		return 0;
190 
191 	/* Due to errata in the dma mode; need to line up enabling
192 	 * the transmitter with a transition on the frame sync
193 	 * line */
194 
195 	/* first make sure it is low */
196 	while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) != 0)
197 		;
198 	/* then wait for the transition to high */
199 	while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) == 0)
200 		;
201 	/* Finally, enable the PSC.
202 	 * Receiver must always be enabled; even when we only want
203 	 * transmit.  (see 15.3.2.3 of MPC5200B User's Guide) */
204 
205 	/* Go */
206 	out_8(&psc_dma->psc_regs->command,
207 			MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
208 
209 	return 0;
210 
211 }
212 
213 static int psc_i2s_of_remove(struct platform_device *op)
214 {
215 	mpc5200_audio_dma_destroy(op);
216 	snd_soc_unregister_component(&op->dev);
217 	return 0;
218 }
219 
220 /* Match table for of_platform binding */
221 static struct of_device_id psc_i2s_match[] = {
222 	{ .compatible = "fsl,mpc5200-psc-i2s", },
223 	{ .compatible = "fsl,mpc5200b-psc-i2s", },
224 	{}
225 };
226 MODULE_DEVICE_TABLE(of, psc_i2s_match);
227 
228 static struct platform_driver psc_i2s_driver = {
229 	.probe = psc_i2s_of_probe,
230 	.remove = psc_i2s_of_remove,
231 	.driver = {
232 		.name = "mpc5200-psc-i2s",
233 		.owner = THIS_MODULE,
234 		.of_match_table = psc_i2s_match,
235 	},
236 };
237 
238 module_platform_driver(psc_i2s_driver);
239 
240 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
241 MODULE_DESCRIPTION("Freescale MPC5200 PSC in I2S mode ASoC Driver");
242 MODULE_LICENSE("GPL");
243 
244