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(®s->ipcr_acr.ipcr) & 0x80) != 0)
196 ;
197 /* then wait for the transition to high */
198 while ((in_8(®s->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
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