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_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_CONTINUOUS
30
31 /**
32 * PSC_I2S_FORMATS: audio formats supported by the PSC I2S mode
33 */
34 #define PSC_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | \
35 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE)
36
psc_i2s_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params,struct snd_soc_dai * dai)37 static int psc_i2s_hw_params(struct snd_pcm_substream *substream,
38 struct snd_pcm_hw_params *params,
39 struct snd_soc_dai *dai)
40 {
41 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
42 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
43 u32 mode;
44
45 dev_dbg(psc_dma->dev, "%s(substream=%p) p_size=%i p_bytes=%i"
46 " periods=%i buffer_size=%i buffer_bytes=%i\n",
47 __func__, substream, params_period_size(params),
48 params_period_bytes(params), params_periods(params),
49 params_buffer_size(params), params_buffer_bytes(params));
50
51 switch (params_format(params)) {
52 case SNDRV_PCM_FORMAT_S8:
53 mode = MPC52xx_PSC_SICR_SIM_CODEC_8;
54 break;
55 case SNDRV_PCM_FORMAT_S16_BE:
56 mode = MPC52xx_PSC_SICR_SIM_CODEC_16;
57 break;
58 case SNDRV_PCM_FORMAT_S24_BE:
59 mode = MPC52xx_PSC_SICR_SIM_CODEC_24;
60 break;
61 case SNDRV_PCM_FORMAT_S32_BE:
62 mode = MPC52xx_PSC_SICR_SIM_CODEC_32;
63 break;
64 default:
65 dev_dbg(psc_dma->dev, "invalid format\n");
66 return -EINVAL;
67 }
68 out_be32(&psc_dma->psc_regs->sicr, psc_dma->sicr | mode);
69
70 return 0;
71 }
72
73 /**
74 * psc_i2s_set_sysclk: set the clock frequency and direction
75 *
76 * This function is called by the machine driver to tell us what the clock
77 * frequency and direction are.
78 *
79 * Currently, we only support operating as a clock slave (SND_SOC_CLOCK_IN),
80 * and we don't care about the frequency. Return an error if the direction
81 * is not SND_SOC_CLOCK_IN.
82 *
83 * @clk_id: reserved, should be zero
84 * @freq: the frequency of the given clock ID, currently ignored
85 * @dir: SND_SOC_CLOCK_IN (clock slave) or SND_SOC_CLOCK_OUT (clock master)
86 */
psc_i2s_set_sysclk(struct snd_soc_dai * cpu_dai,int clk_id,unsigned int freq,int dir)87 static int psc_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
88 int clk_id, unsigned int freq, int dir)
89 {
90 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(cpu_dai);
91 dev_dbg(psc_dma->dev, "psc_i2s_set_sysclk(cpu_dai=%p, dir=%i)\n",
92 cpu_dai, dir);
93 return (dir == SND_SOC_CLOCK_IN) ? 0 : -EINVAL;
94 }
95
96 /**
97 * psc_i2s_set_fmt: set the serial format.
98 *
99 * This function is called by the machine driver to tell us what serial
100 * format to use.
101 *
102 * This driver only supports I2S mode. Return an error if the format is
103 * not SND_SOC_DAIFMT_I2S.
104 *
105 * @format: one of SND_SOC_DAIFMT_xxx
106 */
psc_i2s_set_fmt(struct snd_soc_dai * cpu_dai,unsigned int format)107 static int psc_i2s_set_fmt(struct snd_soc_dai *cpu_dai, unsigned int format)
108 {
109 struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(cpu_dai);
110 dev_dbg(psc_dma->dev, "psc_i2s_set_fmt(cpu_dai=%p, format=%i)\n",
111 cpu_dai, format);
112 return (format == SND_SOC_DAIFMT_I2S) ? 0 : -EINVAL;
113 }
114
115 /* ---------------------------------------------------------------------
116 * ALSA SoC Bindings
117 *
118 * - Digital Audio Interface (DAI) template
119 * - create/destroy dai hooks
120 */
121
122 /**
123 * psc_i2s_dai_template: template CPU Digital Audio Interface
124 */
125 static const struct snd_soc_dai_ops psc_i2s_dai_ops = {
126 .hw_params = psc_i2s_hw_params,
127 .set_sysclk = psc_i2s_set_sysclk,
128 .set_fmt = psc_i2s_set_fmt,
129 };
130
131 static struct snd_soc_dai_driver psc_i2s_dai[] = {{
132 .name = "mpc5200-psc-i2s.0",
133 .playback = {
134 .stream_name = "I2S Playback",
135 .channels_min = 2,
136 .channels_max = 2,
137 .rates = PSC_I2S_RATES,
138 .formats = PSC_I2S_FORMATS,
139 },
140 .capture = {
141 .stream_name = "I2S Capture",
142 .channels_min = 2,
143 .channels_max = 2,
144 .rates = PSC_I2S_RATES,
145 .formats = PSC_I2S_FORMATS,
146 },
147 .ops = &psc_i2s_dai_ops,
148 } };
149
150 static const struct snd_soc_component_driver psc_i2s_component = {
151 .name = "mpc5200-i2s",
152 .legacy_dai_naming = 1,
153 };
154
155 /* ---------------------------------------------------------------------
156 * OF platform bus binding code:
157 * - Probe/remove operations
158 * - OF device match table
159 */
psc_i2s_of_probe(struct platform_device * op)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(®s->ipcr_acr.ipcr) & 0x80) != 0)
197 ;
198 /* then wait for the transition to high */
199 while ((in_8(®s->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
psc_i2s_of_remove(struct platform_device * op)213 static void psc_i2s_of_remove(struct platform_device *op)
214 {
215 mpc5200_audio_dma_destroy(op);
216 snd_soc_unregister_component(&op->dev);
217 }
218
219 /* Match table for of_platform binding */
220 static const struct of_device_id psc_i2s_match[] = {
221 { .compatible = "fsl,mpc5200-psc-i2s", },
222 { .compatible = "fsl,mpc5200b-psc-i2s", },
223 {}
224 };
225 MODULE_DEVICE_TABLE(of, psc_i2s_match);
226
227 static struct platform_driver psc_i2s_driver = {
228 .probe = psc_i2s_of_probe,
229 .remove_new = psc_i2s_of_remove,
230 .driver = {
231 .name = "mpc5200-psc-i2s",
232 .of_match_table = psc_i2s_match,
233 },
234 };
235
236 module_platform_driver(psc_i2s_driver);
237
238 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
239 MODULE_DESCRIPTION("Freescale MPC5200 PSC in I2S mode ASoC Driver");
240 MODULE_LICENSE("GPL");
241
242