xref: /openbmc/linux/sound/soc/pxa/pxa2xx-i2s.c (revision 5bd8e16d) 
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 	BUG_ON(IS_ERR(clk_i2s));
169 	clk_prepare_enable(clk_i2s);
170 	clk_ena = 1;
171 	pxa_i2s_wait();
172 
173 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
174 		dma_data = &pxa2xx_i2s_pcm_stereo_out;
175 	else
176 		dma_data = &pxa2xx_i2s_pcm_stereo_in;
177 
178 	snd_soc_dai_set_dma_data(dai, substream, dma_data);
179 
180 	/* is port used by another stream */
181 	if (!(SACR0 & SACR0_ENB)) {
182 		SACR0 = 0;
183 		if (pxa_i2s.master)
184 			SACR0 |= SACR0_BCKD;
185 
186 		SACR0 |= SACR0_RFTH(14) | SACR0_TFTH(1);
187 		SACR1 |= pxa_i2s.fmt;
188 	}
189 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
190 		SAIMR |= SAIMR_TFS;
191 	else
192 		SAIMR |= SAIMR_RFS;
193 
194 	switch (params_rate(params)) {
195 	case 8000:
196 		SADIV = 0x48;
197 		break;
198 	case 11025:
199 		SADIV = 0x34;
200 		break;
201 	case 16000:
202 		SADIV = 0x24;
203 		break;
204 	case 22050:
205 		SADIV = 0x1a;
206 		break;
207 	case 44100:
208 		SADIV = 0xd;
209 		break;
210 	case 48000:
211 		SADIV = 0xc;
212 		break;
213 	case 96000: /* not in manual and possibly slightly inaccurate */
214 		SADIV = 0x6;
215 		break;
216 	}
217 
218 	return 0;
219 }
220 
221 static int pxa2xx_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
222 			      struct snd_soc_dai *dai)
223 {
224 	int ret = 0;
225 
226 	switch (cmd) {
227 	case SNDRV_PCM_TRIGGER_START:
228 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
229 			SACR1 &= ~SACR1_DRPL;
230 		else
231 			SACR1 &= ~SACR1_DREC;
232 		SACR0 |= SACR0_ENB;
233 		break;
234 	case SNDRV_PCM_TRIGGER_RESUME:
235 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
236 	case SNDRV_PCM_TRIGGER_STOP:
237 	case SNDRV_PCM_TRIGGER_SUSPEND:
238 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
239 		break;
240 	default:
241 		ret = -EINVAL;
242 	}
243 
244 	return ret;
245 }
246 
247 static void pxa2xx_i2s_shutdown(struct snd_pcm_substream *substream,
248 				struct snd_soc_dai *dai)
249 {
250 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
251 		SACR1 |= SACR1_DRPL;
252 		SAIMR &= ~SAIMR_TFS;
253 	} else {
254 		SACR1 |= SACR1_DREC;
255 		SAIMR &= ~SAIMR_RFS;
256 	}
257 
258 	if ((SACR1 & (SACR1_DREC | SACR1_DRPL)) == (SACR1_DREC | SACR1_DRPL)) {
259 		SACR0 &= ~SACR0_ENB;
260 		pxa_i2s_wait();
261 		if (clk_ena) {
262 			clk_disable_unprepare(clk_i2s);
263 			clk_ena = 0;
264 		}
265 	}
266 }
267 
268 #ifdef CONFIG_PM
269 static int pxa2xx_i2s_suspend(struct snd_soc_dai *dai)
270 {
271 	/* store registers */
272 	pxa_i2s.sacr0 = SACR0;
273 	pxa_i2s.sacr1 = SACR1;
274 	pxa_i2s.saimr = SAIMR;
275 	pxa_i2s.sadiv = SADIV;
276 
277 	/* deactivate link */
278 	SACR0 &= ~SACR0_ENB;
279 	pxa_i2s_wait();
280 	return 0;
281 }
282 
283 static int pxa2xx_i2s_resume(struct snd_soc_dai *dai)
284 {
285 	pxa_i2s_wait();
286 
287 	SACR0 = pxa_i2s.sacr0 & ~SACR0_ENB;
288 	SACR1 = pxa_i2s.sacr1;
289 	SAIMR = pxa_i2s.saimr;
290 	SADIV = pxa_i2s.sadiv;
291 
292 	SACR0 = pxa_i2s.sacr0;
293 
294 	return 0;
295 }
296 
297 #else
298 #define pxa2xx_i2s_suspend	NULL
299 #define pxa2xx_i2s_resume	NULL
300 #endif
301 
302 static int pxa2xx_i2s_probe(struct snd_soc_dai *dai)
303 {
304 	clk_i2s = clk_get(dai->dev, "I2SCLK");
305 	if (IS_ERR(clk_i2s))
306 		return PTR_ERR(clk_i2s);
307 
308 	/*
309 	 * PXA Developer's Manual:
310 	 * If SACR0[ENB] is toggled in the middle of a normal operation,
311 	 * the SACR0[RST] bit must also be set and cleared to reset all
312 	 * I2S controller registers.
313 	 */
314 	SACR0 = SACR0_RST;
315 	SACR0 = 0;
316 	/* Make sure RPL and REC are disabled */
317 	SACR1 = SACR1_DRPL | SACR1_DREC;
318 	/* Along with FIFO servicing */
319 	SAIMR &= ~(SAIMR_RFS | SAIMR_TFS);
320 
321 	return 0;
322 }
323 
324 static int  pxa2xx_i2s_remove(struct snd_soc_dai *dai)
325 {
326 	clk_put(clk_i2s);
327 	clk_i2s = ERR_PTR(-ENOENT);
328 	return 0;
329 }
330 
331 #define PXA2XX_I2S_RATES (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_11025 |\
332 		SNDRV_PCM_RATE_16000 | SNDRV_PCM_RATE_22050 | SNDRV_PCM_RATE_44100 | \
333 		SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_96000)
334 
335 static const struct snd_soc_dai_ops pxa_i2s_dai_ops = {
336 	.startup	= pxa2xx_i2s_startup,
337 	.shutdown	= pxa2xx_i2s_shutdown,
338 	.trigger	= pxa2xx_i2s_trigger,
339 	.hw_params	= pxa2xx_i2s_hw_params,
340 	.set_fmt	= pxa2xx_i2s_set_dai_fmt,
341 	.set_sysclk	= pxa2xx_i2s_set_dai_sysclk,
342 };
343 
344 static struct snd_soc_dai_driver pxa_i2s_dai = {
345 	.probe = pxa2xx_i2s_probe,
346 	.remove = pxa2xx_i2s_remove,
347 	.suspend = pxa2xx_i2s_suspend,
348 	.resume = pxa2xx_i2s_resume,
349 	.playback = {
350 		.channels_min = 2,
351 		.channels_max = 2,
352 		.rates = PXA2XX_I2S_RATES,
353 		.formats = SNDRV_PCM_FMTBIT_S16_LE,},
354 	.capture = {
355 		.channels_min = 2,
356 		.channels_max = 2,
357 		.rates = PXA2XX_I2S_RATES,
358 		.formats = SNDRV_PCM_FMTBIT_S16_LE,},
359 	.ops = &pxa_i2s_dai_ops,
360 	.symmetric_rates = 1,
361 };
362 
363 static const struct snd_soc_component_driver pxa_i2s_component = {
364 	.name		= "pxa-i2s",
365 };
366 
367 static int pxa2xx_i2s_drv_probe(struct platform_device *pdev)
368 {
369 	return snd_soc_register_component(&pdev->dev, &pxa_i2s_component,
370 					  &pxa_i2s_dai, 1);
371 }
372 
373 static int pxa2xx_i2s_drv_remove(struct platform_device *pdev)
374 {
375 	snd_soc_unregister_component(&pdev->dev);
376 	return 0;
377 }
378 
379 static struct platform_driver pxa2xx_i2s_driver = {
380 	.probe = pxa2xx_i2s_drv_probe,
381 	.remove = pxa2xx_i2s_drv_remove,
382 
383 	.driver = {
384 		.name = "pxa2xx-i2s",
385 		.owner = THIS_MODULE,
386 	},
387 };
388 
389 static int __init pxa2xx_i2s_init(void)
390 {
391 	clk_i2s = ERR_PTR(-ENOENT);
392 	return platform_driver_register(&pxa2xx_i2s_driver);
393 }
394 
395 static void __exit pxa2xx_i2s_exit(void)
396 {
397 	platform_driver_unregister(&pxa2xx_i2s_driver);
398 }
399 
400 module_init(pxa2xx_i2s_init);
401 module_exit(pxa2xx_i2s_exit);
402 
403 /* Module information */
404 MODULE_AUTHOR("Liam Girdwood, lrg@slimlogic.co.uk");
405 MODULE_DESCRIPTION("pxa2xx I2S SoC Interface");
406 MODULE_LICENSE("GPL");
407 MODULE_ALIAS("platform:pxa2xx-i2s");
408