xref: /openbmc/linux/sound/soc/pxa/pxa2xx-i2s.c (revision 7bcae826) 
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 unsigned long pxa2xx_i2s_pcm_stereo_out_req = 3;
86 static struct snd_dmaengine_dai_dma_data pxa2xx_i2s_pcm_stereo_out = {
87 	.addr		= __PREG(SADR),
88 	.addr_width	= DMA_SLAVE_BUSWIDTH_4_BYTES,
89 	.maxburst	= 32,
90 	.filter_data	= &pxa2xx_i2s_pcm_stereo_out_req,
91 };
92 
93 static unsigned long pxa2xx_i2s_pcm_stereo_in_req = 2;
94 static struct snd_dmaengine_dai_dma_data pxa2xx_i2s_pcm_stereo_in = {
95 	.addr		= __PREG(SADR),
96 	.addr_width	= DMA_SLAVE_BUSWIDTH_4_BYTES,
97 	.maxburst	= 32,
98 	.filter_data	= &pxa2xx_i2s_pcm_stereo_in_req,
99 };
100 
101 static int pxa2xx_i2s_startup(struct snd_pcm_substream *substream,
102 			      struct snd_soc_dai *dai)
103 {
104 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
105 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
106 
107 	if (IS_ERR(clk_i2s))
108 		return PTR_ERR(clk_i2s);
109 
110 	if (!cpu_dai->active)
111 		SACR0 = 0;
112 
113 	return 0;
114 }
115 
116 /* wait for I2S controller to be ready */
117 static int pxa_i2s_wait(void)
118 {
119 	int i;
120 
121 	/* flush the Rx FIFO */
122 	for(i = 0; i < 16; i++)
123 		SADR;
124 	return 0;
125 }
126 
127 static int pxa2xx_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai,
128 		unsigned int fmt)
129 {
130 	/* interface format */
131 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
132 	case SND_SOC_DAIFMT_I2S:
133 		pxa_i2s.fmt = 0;
134 		break;
135 	case SND_SOC_DAIFMT_LEFT_J:
136 		pxa_i2s.fmt = SACR1_AMSL;
137 		break;
138 	}
139 
140 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
141 	case SND_SOC_DAIFMT_CBS_CFS:
142 		pxa_i2s.master = 1;
143 		break;
144 	case SND_SOC_DAIFMT_CBM_CFS:
145 		pxa_i2s.master = 0;
146 		break;
147 	default:
148 		break;
149 	}
150 	return 0;
151 }
152 
153 static int pxa2xx_i2s_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
154 		int clk_id, unsigned int freq, int dir)
155 {
156 	if (clk_id != PXA2XX_I2S_SYSCLK)
157 		return -ENODEV;
158 
159 	return 0;
160 }
161 
162 static int pxa2xx_i2s_hw_params(struct snd_pcm_substream *substream,
163 				struct snd_pcm_hw_params *params,
164 				struct snd_soc_dai *dai)
165 {
166 	struct snd_dmaengine_dai_dma_data *dma_data;
167 
168 	if (WARN_ON(IS_ERR(clk_i2s)))
169 		return -EINVAL;
170 	clk_prepare_enable(clk_i2s);
171 	clk_ena = 1;
172 	pxa_i2s_wait();
173 
174 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
175 		dma_data = &pxa2xx_i2s_pcm_stereo_out;
176 	else
177 		dma_data = &pxa2xx_i2s_pcm_stereo_in;
178 
179 	snd_soc_dai_set_dma_data(dai, substream, dma_data);
180 
181 	/* is port used by another stream */
182 	if (!(SACR0 & SACR0_ENB)) {
183 		SACR0 = 0;
184 		if (pxa_i2s.master)
185 			SACR0 |= SACR0_BCKD;
186 
187 		SACR0 |= SACR0_RFTH(14) | SACR0_TFTH(1);
188 		SACR1 |= pxa_i2s.fmt;
189 	}
190 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
191 		SAIMR |= SAIMR_TFS;
192 	else
193 		SAIMR |= SAIMR_RFS;
194 
195 	switch (params_rate(params)) {
196 	case 8000:
197 		SADIV = 0x48;
198 		break;
199 	case 11025:
200 		SADIV = 0x34;
201 		break;
202 	case 16000:
203 		SADIV = 0x24;
204 		break;
205 	case 22050:
206 		SADIV = 0x1a;
207 		break;
208 	case 44100:
209 		SADIV = 0xd;
210 		break;
211 	case 48000:
212 		SADIV = 0xc;
213 		break;
214 	case 96000: /* not in manual and possibly slightly inaccurate */
215 		SADIV = 0x6;
216 		break;
217 	}
218 
219 	return 0;
220 }
221 
222 static int pxa2xx_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
223 			      struct snd_soc_dai *dai)
224 {
225 	int ret = 0;
226 
227 	switch (cmd) {
228 	case SNDRV_PCM_TRIGGER_START:
229 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
230 			SACR1 &= ~SACR1_DRPL;
231 		else
232 			SACR1 &= ~SACR1_DREC;
233 		SACR0 |= SACR0_ENB;
234 		break;
235 	case SNDRV_PCM_TRIGGER_RESUME:
236 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
237 	case SNDRV_PCM_TRIGGER_STOP:
238 	case SNDRV_PCM_TRIGGER_SUSPEND:
239 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
240 		break;
241 	default:
242 		ret = -EINVAL;
243 	}
244 
245 	return ret;
246 }
247 
248 static void pxa2xx_i2s_shutdown(struct snd_pcm_substream *substream,
249 				struct snd_soc_dai *dai)
250 {
251 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
252 		SACR1 |= SACR1_DRPL;
253 		SAIMR &= ~SAIMR_TFS;
254 	} else {
255 		SACR1 |= SACR1_DREC;
256 		SAIMR &= ~SAIMR_RFS;
257 	}
258 
259 	if ((SACR1 & (SACR1_DREC | SACR1_DRPL)) == (SACR1_DREC | SACR1_DRPL)) {
260 		SACR0 &= ~SACR0_ENB;
261 		pxa_i2s_wait();
262 		if (clk_ena) {
263 			clk_disable_unprepare(clk_i2s);
264 			clk_ena = 0;
265 		}
266 	}
267 }
268 
269 #ifdef CONFIG_PM
270 static int pxa2xx_i2s_suspend(struct snd_soc_dai *dai)
271 {
272 	/* store registers */
273 	pxa_i2s.sacr0 = SACR0;
274 	pxa_i2s.sacr1 = SACR1;
275 	pxa_i2s.saimr = SAIMR;
276 	pxa_i2s.sadiv = SADIV;
277 
278 	/* deactivate link */
279 	SACR0 &= ~SACR0_ENB;
280 	pxa_i2s_wait();
281 	return 0;
282 }
283 
284 static int pxa2xx_i2s_resume(struct snd_soc_dai *dai)
285 {
286 	pxa_i2s_wait();
287 
288 	SACR0 = pxa_i2s.sacr0 & ~SACR0_ENB;
289 	SACR1 = pxa_i2s.sacr1;
290 	SAIMR = pxa_i2s.saimr;
291 	SADIV = pxa_i2s.sadiv;
292 
293 	SACR0 = pxa_i2s.sacr0;
294 
295 	return 0;
296 }
297 
298 #else
299 #define pxa2xx_i2s_suspend	NULL
300 #define pxa2xx_i2s_resume	NULL
301 #endif
302 
303 static int pxa2xx_i2s_probe(struct snd_soc_dai *dai)
304 {
305 	clk_i2s = clk_get(dai->dev, "I2SCLK");
306 	if (IS_ERR(clk_i2s))
307 		return PTR_ERR(clk_i2s);
308 
309 	/*
310 	 * PXA Developer's Manual:
311 	 * If SACR0[ENB] is toggled in the middle of a normal operation,
312 	 * the SACR0[RST] bit must also be set and cleared to reset all
313 	 * I2S controller registers.
314 	 */
315 	SACR0 = SACR0_RST;
316 	SACR0 = 0;
317 	/* Make sure RPL and REC are disabled */
318 	SACR1 = SACR1_DRPL | SACR1_DREC;
319 	/* Along with FIFO servicing */
320 	SAIMR &= ~(SAIMR_RFS | SAIMR_TFS);
321 
322 	snd_soc_dai_init_dma_data(dai, &pxa2xx_i2s_pcm_stereo_out,
323 		&pxa2xx_i2s_pcm_stereo_in);
324 
325 	return 0;
326 }
327 
328 static int  pxa2xx_i2s_remove(struct snd_soc_dai *dai)
329 {
330 	clk_put(clk_i2s);
331 	clk_i2s = ERR_PTR(-ENOENT);
332 	return 0;
333 }
334 
335 #define PXA2XX_I2S_RATES (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_11025 |\
336 		SNDRV_PCM_RATE_16000 | SNDRV_PCM_RATE_22050 | SNDRV_PCM_RATE_44100 | \
337 		SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_96000)
338 
339 static const struct snd_soc_dai_ops pxa_i2s_dai_ops = {
340 	.startup	= pxa2xx_i2s_startup,
341 	.shutdown	= pxa2xx_i2s_shutdown,
342 	.trigger	= pxa2xx_i2s_trigger,
343 	.hw_params	= pxa2xx_i2s_hw_params,
344 	.set_fmt	= pxa2xx_i2s_set_dai_fmt,
345 	.set_sysclk	= pxa2xx_i2s_set_dai_sysclk,
346 };
347 
348 static struct snd_soc_dai_driver pxa_i2s_dai = {
349 	.probe = pxa2xx_i2s_probe,
350 	.remove = pxa2xx_i2s_remove,
351 	.suspend = pxa2xx_i2s_suspend,
352 	.resume = pxa2xx_i2s_resume,
353 	.playback = {
354 		.channels_min = 2,
355 		.channels_max = 2,
356 		.rates = PXA2XX_I2S_RATES,
357 		.formats = SNDRV_PCM_FMTBIT_S16_LE,},
358 	.capture = {
359 		.channels_min = 2,
360 		.channels_max = 2,
361 		.rates = PXA2XX_I2S_RATES,
362 		.formats = SNDRV_PCM_FMTBIT_S16_LE,},
363 	.ops = &pxa_i2s_dai_ops,
364 	.symmetric_rates = 1,
365 };
366 
367 static const struct snd_soc_component_driver pxa_i2s_component = {
368 	.name		= "pxa-i2s",
369 };
370 
371 static int pxa2xx_i2s_drv_probe(struct platform_device *pdev)
372 {
373 	return devm_snd_soc_register_component(&pdev->dev, &pxa_i2s_component,
374 					       &pxa_i2s_dai, 1);
375 }
376 
377 static struct platform_driver pxa2xx_i2s_driver = {
378 	.probe = pxa2xx_i2s_drv_probe,
379 
380 	.driver = {
381 		.name = "pxa2xx-i2s",
382 	},
383 };
384 
385 static int __init pxa2xx_i2s_init(void)
386 {
387 	clk_i2s = ERR_PTR(-ENOENT);
388 	return platform_driver_register(&pxa2xx_i2s_driver);
389 }
390 
391 static void __exit pxa2xx_i2s_exit(void)
392 {
393 	platform_driver_unregister(&pxa2xx_i2s_driver);
394 }
395 
396 module_init(pxa2xx_i2s_init);
397 module_exit(pxa2xx_i2s_exit);
398 
399 /* Module information */
400 MODULE_AUTHOR("Liam Girdwood, lrg@slimlogic.co.uk");
401 MODULE_DESCRIPTION("pxa2xx I2S SoC Interface");
402 MODULE_LICENSE("GPL");
403 MODULE_ALIAS("platform:pxa2xx-i2s");
404