xref: /openbmc/linux/sound/soc/pxa/pxa2xx-i2s.c (revision ebd09753) 
1 /*
2  * pxa2xx-i2s.c  --  ALSA Soc Audio Layer
3  *
4  * Copyright 2005 Wolfson Microelectronics PLC.
5  * Author: Liam Girdwood
6  *         lrg@slimlogic.co.uk
7  *
8  *  This program is free software; you can redistribute  it and/or modify it
9  *  under  the terms of  the GNU General  Public License as published by the
10  *  Free Software Foundation;  either version 2 of the  License, or (at your
11  *  option) any later version.
12  */
13 
14 #include <linux/init.h>
15 #include <linux/module.h>
16 #include <linux/device.h>
17 #include <linux/delay.h>
18 #include <linux/clk.h>
19 #include <linux/platform_device.h>
20 #include <linux/io.h>
21 #include <sound/core.h>
22 #include <sound/pcm.h>
23 #include <sound/initval.h>
24 #include <sound/soc.h>
25 #include <sound/pxa2xx-lib.h>
26 #include <sound/dmaengine_pcm.h>
27 
28 #include <mach/hardware.h>
29 #include <mach/audio.h>
30 
31 #include "pxa2xx-i2s.h"
32 
33 /*
34  * I2S Controller Register and Bit Definitions
35  */
36 #define SACR0		__REG(0x40400000)  /* Global Control Register */
37 #define SACR1		__REG(0x40400004)  /* Serial Audio I 2 S/MSB-Justified Control Register */
38 #define SASR0		__REG(0x4040000C)  /* Serial Audio I 2 S/MSB-Justified Interface and FIFO Status Register */
39 #define SAIMR		__REG(0x40400014)  /* Serial Audio Interrupt Mask Register */
40 #define SAICR		__REG(0x40400018)  /* Serial Audio Interrupt Clear Register */
41 #define SADIV		__REG(0x40400060)  /* Audio Clock Divider Register. */
42 #define SADR		__REG(0x40400080)  /* Serial Audio Data Register (TX and RX FIFO access Register). */
43 
44 #define SACR0_RFTH(x)	((x) << 12)	/* Rx FIFO Interrupt or DMA Trigger Threshold */
45 #define SACR0_TFTH(x)	((x) << 8)	/* Tx FIFO Interrupt or DMA Trigger Threshold */
46 #define SACR0_STRF	(1 << 5)	/* FIFO Select for EFWR Special Function */
47 #define SACR0_EFWR	(1 << 4)	/* Enable EFWR Function  */
48 #define SACR0_RST	(1 << 3)	/* FIFO, i2s Register Reset */
49 #define SACR0_BCKD	(1 << 2)	/* Bit Clock Direction */
50 #define SACR0_ENB	(1 << 0)	/* Enable I2S Link */
51 #define SACR1_ENLBF	(1 << 5)	/* Enable Loopback */
52 #define SACR1_DRPL	(1 << 4)	/* Disable Replaying Function */
53 #define SACR1_DREC	(1 << 3)	/* Disable Recording Function */
54 #define SACR1_AMSL	(1 << 0)	/* Specify Alternate Mode */
55 
56 #define SASR0_I2SOFF	(1 << 7)	/* Controller Status */
57 #define SASR0_ROR	(1 << 6)	/* Rx FIFO Overrun */
58 #define SASR0_TUR	(1 << 5)	/* Tx FIFO Underrun */
59 #define SASR0_RFS	(1 << 4)	/* Rx FIFO Service Request */
60 #define SASR0_TFS	(1 << 3)	/* Tx FIFO Service Request */
61 #define SASR0_BSY	(1 << 2)	/* I2S Busy */
62 #define SASR0_RNE	(1 << 1)	/* Rx FIFO Not Empty */
63 #define SASR0_TNF	(1 << 0)	/* Tx FIFO Not Empty */
64 
65 #define SAICR_ROR	(1 << 6)	/* Clear Rx FIFO Overrun Interrupt */
66 #define SAICR_TUR	(1 << 5)	/* Clear Tx FIFO Underrun Interrupt */
67 
68 #define SAIMR_ROR	(1 << 6)	/* Enable Rx FIFO Overrun Condition Interrupt */
69 #define SAIMR_TUR	(1 << 5)	/* Enable Tx FIFO Underrun Condition Interrupt */
70 #define SAIMR_RFS	(1 << 4)	/* Enable Rx FIFO Service Interrupt */
71 #define SAIMR_TFS	(1 << 3)	/* Enable Tx FIFO Service Interrupt */
72 
73 struct pxa_i2s_port {
74 	u32 sadiv;
75 	u32 sacr0;
76 	u32 sacr1;
77 	u32 saimr;
78 	int master;
79 	u32 fmt;
80 };
81 static struct pxa_i2s_port pxa_i2s;
82 static struct clk *clk_i2s;
83 static int clk_ena = 0;
84 
85 static struct snd_dmaengine_dai_dma_data pxa2xx_i2s_pcm_stereo_out = {
86 	.addr		= __PREG(SADR),
87 	.addr_width	= DMA_SLAVE_BUSWIDTH_4_BYTES,
88 	.chan_name	= "tx",
89 	.maxburst	= 32,
90 };
91 
92 static struct snd_dmaengine_dai_dma_data pxa2xx_i2s_pcm_stereo_in = {
93 	.addr		= __PREG(SADR),
94 	.addr_width	= DMA_SLAVE_BUSWIDTH_4_BYTES,
95 	.chan_name	= "rx",
96 	.maxburst	= 32,
97 };
98 
99 static int pxa2xx_i2s_startup(struct snd_pcm_substream *substream,
100 			      struct snd_soc_dai *dai)
101 {
102 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
103 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
104 
105 	if (IS_ERR(clk_i2s))
106 		return PTR_ERR(clk_i2s);
107 
108 	if (!cpu_dai->active)
109 		SACR0 = 0;
110 
111 	return 0;
112 }
113 
114 /* wait for I2S controller to be ready */
115 static int pxa_i2s_wait(void)
116 {
117 	int i;
118 
119 	/* flush the Rx FIFO */
120 	for (i = 0; i < 16; i++)
121 		SADR;
122 	return 0;
123 }
124 
125 static int pxa2xx_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai,
126 		unsigned int fmt)
127 {
128 	/* interface format */
129 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
130 	case SND_SOC_DAIFMT_I2S:
131 		pxa_i2s.fmt = 0;
132 		break;
133 	case SND_SOC_DAIFMT_LEFT_J:
134 		pxa_i2s.fmt = SACR1_AMSL;
135 		break;
136 	}
137 
138 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
139 	case SND_SOC_DAIFMT_CBS_CFS:
140 		pxa_i2s.master = 1;
141 		break;
142 	case SND_SOC_DAIFMT_CBM_CFS:
143 		pxa_i2s.master = 0;
144 		break;
145 	default:
146 		break;
147 	}
148 	return 0;
149 }
150 
151 static int pxa2xx_i2s_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
152 		int clk_id, unsigned int freq, int dir)
153 {
154 	if (clk_id != PXA2XX_I2S_SYSCLK)
155 		return -ENODEV;
156 
157 	return 0;
158 }
159 
160 static int pxa2xx_i2s_hw_params(struct snd_pcm_substream *substream,
161 				struct snd_pcm_hw_params *params,
162 				struct snd_soc_dai *dai)
163 {
164 	struct snd_dmaengine_dai_dma_data *dma_data;
165 
166 	if (WARN_ON(IS_ERR(clk_i2s)))
167 		return -EINVAL;
168 	clk_prepare_enable(clk_i2s);
169 	clk_ena = 1;
170 	pxa_i2s_wait();
171 
172 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
173 		dma_data = &pxa2xx_i2s_pcm_stereo_out;
174 	else
175 		dma_data = &pxa2xx_i2s_pcm_stereo_in;
176 
177 	snd_soc_dai_set_dma_data(dai, substream, dma_data);
178 
179 	/* is port used by another stream */
180 	if (!(SACR0 & SACR0_ENB)) {
181 		SACR0 = 0;
182 		if (pxa_i2s.master)
183 			SACR0 |= SACR0_BCKD;
184 
185 		SACR0 |= SACR0_RFTH(14) | SACR0_TFTH(1);
186 		SACR1 |= pxa_i2s.fmt;
187 	}
188 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
189 		SAIMR |= SAIMR_TFS;
190 	else
191 		SAIMR |= SAIMR_RFS;
192 
193 	switch (params_rate(params)) {
194 	case 8000:
195 		SADIV = 0x48;
196 		break;
197 	case 11025:
198 		SADIV = 0x34;
199 		break;
200 	case 16000:
201 		SADIV = 0x24;
202 		break;
203 	case 22050:
204 		SADIV = 0x1a;
205 		break;
206 	case 44100:
207 		SADIV = 0xd;
208 		break;
209 	case 48000:
210 		SADIV = 0xc;
211 		break;
212 	case 96000: /* not in manual and possibly slightly inaccurate */
213 		SADIV = 0x6;
214 		break;
215 	}
216 
217 	return 0;
218 }
219 
220 static int pxa2xx_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
221 			      struct snd_soc_dai *dai)
222 {
223 	int ret = 0;
224 
225 	switch (cmd) {
226 	case SNDRV_PCM_TRIGGER_START:
227 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
228 			SACR1 &= ~SACR1_DRPL;
229 		else
230 			SACR1 &= ~SACR1_DREC;
231 		SACR0 |= SACR0_ENB;
232 		break;
233 	case SNDRV_PCM_TRIGGER_RESUME:
234 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
235 	case SNDRV_PCM_TRIGGER_STOP:
236 	case SNDRV_PCM_TRIGGER_SUSPEND:
237 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
238 		break;
239 	default:
240 		ret = -EINVAL;
241 	}
242 
243 	return ret;
244 }
245 
246 static void pxa2xx_i2s_shutdown(struct snd_pcm_substream *substream,
247 				struct snd_soc_dai *dai)
248 {
249 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
250 		SACR1 |= SACR1_DRPL;
251 		SAIMR &= ~SAIMR_TFS;
252 	} else {
253 		SACR1 |= SACR1_DREC;
254 		SAIMR &= ~SAIMR_RFS;
255 	}
256 
257 	if ((SACR1 & (SACR1_DREC | SACR1_DRPL)) == (SACR1_DREC | SACR1_DRPL)) {
258 		SACR0 &= ~SACR0_ENB;
259 		pxa_i2s_wait();
260 		if (clk_ena) {
261 			clk_disable_unprepare(clk_i2s);
262 			clk_ena = 0;
263 		}
264 	}
265 }
266 
267 #ifdef CONFIG_PM
268 static int pxa2xx_i2s_suspend(struct snd_soc_dai *dai)
269 {
270 	/* store registers */
271 	pxa_i2s.sacr0 = SACR0;
272 	pxa_i2s.sacr1 = SACR1;
273 	pxa_i2s.saimr = SAIMR;
274 	pxa_i2s.sadiv = SADIV;
275 
276 	/* deactivate link */
277 	SACR0 &= ~SACR0_ENB;
278 	pxa_i2s_wait();
279 	return 0;
280 }
281 
282 static int pxa2xx_i2s_resume(struct snd_soc_dai *dai)
283 {
284 	pxa_i2s_wait();
285 
286 	SACR0 = pxa_i2s.sacr0 & ~SACR0_ENB;
287 	SACR1 = pxa_i2s.sacr1;
288 	SAIMR = pxa_i2s.saimr;
289 	SADIV = pxa_i2s.sadiv;
290 
291 	SACR0 = pxa_i2s.sacr0;
292 
293 	return 0;
294 }
295 
296 #else
297 #define pxa2xx_i2s_suspend	NULL
298 #define pxa2xx_i2s_resume	NULL
299 #endif
300 
301 static int pxa2xx_i2s_probe(struct snd_soc_dai *dai)
302 {
303 	clk_i2s = clk_get(dai->dev, "I2SCLK");
304 	if (IS_ERR(clk_i2s))
305 		return PTR_ERR(clk_i2s);
306 
307 	/*
308 	 * PXA Developer's Manual:
309 	 * If SACR0[ENB] is toggled in the middle of a normal operation,
310 	 * the SACR0[RST] bit must also be set and cleared to reset all
311 	 * I2S controller registers.
312 	 */
313 	SACR0 = SACR0_RST;
314 	SACR0 = 0;
315 	/* Make sure RPL and REC are disabled */
316 	SACR1 = SACR1_DRPL | SACR1_DREC;
317 	/* Along with FIFO servicing */
318 	SAIMR &= ~(SAIMR_RFS | SAIMR_TFS);
319 
320 	snd_soc_dai_init_dma_data(dai, &pxa2xx_i2s_pcm_stereo_out,
321 		&pxa2xx_i2s_pcm_stereo_in);
322 
323 	return 0;
324 }
325 
326 static int  pxa2xx_i2s_remove(struct snd_soc_dai *dai)
327 {
328 	clk_put(clk_i2s);
329 	clk_i2s = ERR_PTR(-ENOENT);
330 	return 0;
331 }
332 
333 #define PXA2XX_I2S_RATES (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_11025 |\
334 		SNDRV_PCM_RATE_16000 | SNDRV_PCM_RATE_22050 | SNDRV_PCM_RATE_44100 | \
335 		SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_96000)
336 
337 static const struct snd_soc_dai_ops pxa_i2s_dai_ops = {
338 	.startup	= pxa2xx_i2s_startup,
339 	.shutdown	= pxa2xx_i2s_shutdown,
340 	.trigger	= pxa2xx_i2s_trigger,
341 	.hw_params	= pxa2xx_i2s_hw_params,
342 	.set_fmt	= pxa2xx_i2s_set_dai_fmt,
343 	.set_sysclk	= pxa2xx_i2s_set_dai_sysclk,
344 };
345 
346 static struct snd_soc_dai_driver pxa_i2s_dai = {
347 	.probe = pxa2xx_i2s_probe,
348 	.remove = pxa2xx_i2s_remove,
349 	.suspend = pxa2xx_i2s_suspend,
350 	.resume = pxa2xx_i2s_resume,
351 	.playback = {
352 		.channels_min = 2,
353 		.channels_max = 2,
354 		.rates = PXA2XX_I2S_RATES,
355 		.formats = SNDRV_PCM_FMTBIT_S16_LE,},
356 	.capture = {
357 		.channels_min = 2,
358 		.channels_max = 2,
359 		.rates = PXA2XX_I2S_RATES,
360 		.formats = SNDRV_PCM_FMTBIT_S16_LE,},
361 	.ops = &pxa_i2s_dai_ops,
362 	.symmetric_rates = 1,
363 };
364 
365 static const struct snd_soc_component_driver pxa_i2s_component = {
366 	.name		= "pxa-i2s",
367 	.ops		= &pxa2xx_pcm_ops,
368 	.pcm_new	= pxa2xx_soc_pcm_new,
369 	.pcm_free	= pxa2xx_pcm_free_dma_buffers,
370 };
371 
372 static int pxa2xx_i2s_drv_probe(struct platform_device *pdev)
373 {
374 	return devm_snd_soc_register_component(&pdev->dev, &pxa_i2s_component,
375 					       &pxa_i2s_dai, 1);
376 }
377 
378 static struct platform_driver pxa2xx_i2s_driver = {
379 	.probe = pxa2xx_i2s_drv_probe,
380 
381 	.driver = {
382 		.name = "pxa2xx-i2s",
383 	},
384 };
385 
386 static int __init pxa2xx_i2s_init(void)
387 {
388 	clk_i2s = ERR_PTR(-ENOENT);
389 	return platform_driver_register(&pxa2xx_i2s_driver);
390 }
391 
392 static void __exit pxa2xx_i2s_exit(void)
393 {
394 	platform_driver_unregister(&pxa2xx_i2s_driver);
395 }
396 
397 module_init(pxa2xx_i2s_init);
398 module_exit(pxa2xx_i2s_exit);
399 
400 /* Module information */
401 MODULE_AUTHOR("Liam Girdwood, lrg@slimlogic.co.uk");
402 MODULE_DESCRIPTION("pxa2xx I2S SoC Interface");
403 MODULE_LICENSE("GPL");
404 MODULE_ALIAS("platform:pxa2xx-i2s");
405