xref: /openbmc/linux/sound/soc/au1x/dbdma2.c (revision 1fa6ac37)
1 /*
2  * Au12x0/Au1550 PSC ALSA ASoC audio support.
3  *
4  * (c) 2007-2008 MSC Vertriebsges.m.b.H.,
5  *	Manuel Lauss <manuel.lauss@gmail.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * DMA glue for Au1x-PSC audio.
12  *
13  * NOTE: all of these drivers can only work with a SINGLE instance
14  *	 of a PSC. Multiple independent audio devices are impossible
15  *	 with ASoC v1.
16  */
17 
18 
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/platform_device.h>
22 #include <linux/slab.h>
23 #include <linux/dma-mapping.h>
24 
25 #include <sound/core.h>
26 #include <sound/pcm.h>
27 #include <sound/pcm_params.h>
28 #include <sound/soc.h>
29 
30 #include <asm/mach-au1x00/au1000.h>
31 #include <asm/mach-au1x00/au1xxx_dbdma.h>
32 #include <asm/mach-au1x00/au1xxx_psc.h>
33 
34 #include "psc.h"
35 
36 /*#define PCM_DEBUG*/
37 
38 #define MSG(x...)	printk(KERN_INFO "au1xpsc_pcm: " x)
39 #ifdef PCM_DEBUG
40 #define DBG		MSG
41 #else
42 #define DBG(x...)	do {} while (0)
43 #endif
44 
45 struct au1xpsc_audio_dmadata {
46 	/* DDMA control data */
47 	unsigned int ddma_id;		/* DDMA direction ID for this PSC */
48 	u32 ddma_chan;			/* DDMA context */
49 
50 	/* PCM context (for irq handlers) */
51 	struct snd_pcm_substream *substream;
52 	unsigned long curr_period;	/* current segment DDMA is working on */
53 	unsigned long q_period;		/* queue period(s) */
54 	dma_addr_t dma_area;		/* address of queued DMA area */
55 	dma_addr_t dma_area_s;		/* start address of DMA area */
56 	unsigned long pos;		/* current byte position being played */
57 	unsigned long periods;		/* number of SG segments in total */
58 	unsigned long period_bytes;	/* size in bytes of one SG segment */
59 
60 	/* runtime data */
61 	int msbits;
62 };
63 
64 /* instance data. There can be only one, MacLeod!!!! */
65 static struct au1xpsc_audio_dmadata *au1xpsc_audio_pcmdma[2];
66 
67 /*
68  * These settings are somewhat okay, at least on my machine audio plays
69  * almost skip-free. Especially the 64kB buffer seems to help a LOT.
70  */
71 #define AU1XPSC_PERIOD_MIN_BYTES	1024
72 #define AU1XPSC_BUFFER_MIN_BYTES	65536
73 
74 #define AU1XPSC_PCM_FMTS					\
75 	(SNDRV_PCM_FMTBIT_S8     | SNDRV_PCM_FMTBIT_U8 |	\
76 	 SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S16_BE |	\
77 	 SNDRV_PCM_FMTBIT_U16_LE | SNDRV_PCM_FMTBIT_U16_BE |	\
78 	 SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S32_BE |	\
79 	 SNDRV_PCM_FMTBIT_U32_LE | SNDRV_PCM_FMTBIT_U32_BE |	\
80 	 0)
81 
82 /* PCM hardware DMA capabilities - platform specific */
83 static const struct snd_pcm_hardware au1xpsc_pcm_hardware = {
84 	.info		  = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
85 			    SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH,
86 	.formats	  = AU1XPSC_PCM_FMTS,
87 	.period_bytes_min = AU1XPSC_PERIOD_MIN_BYTES,
88 	.period_bytes_max = 4096 * 1024 - 1,
89 	.periods_min	  = 2,
90 	.periods_max	  = 4096,	/* 2 to as-much-as-you-like */
91 	.buffer_bytes_max = 4096 * 1024 - 1,
92 	.fifo_size	  = 16,		/* fifo entries of AC97/I2S PSC */
93 };
94 
95 static void au1x_pcm_queue_tx(struct au1xpsc_audio_dmadata *cd)
96 {
97 	au1xxx_dbdma_put_source(cd->ddma_chan, cd->dma_area,
98 				cd->period_bytes, DDMA_FLAGS_IE);
99 
100 	/* update next-to-queue period */
101 	++cd->q_period;
102 	cd->dma_area += cd->period_bytes;
103 	if (cd->q_period >= cd->periods) {
104 		cd->q_period = 0;
105 		cd->dma_area = cd->dma_area_s;
106 	}
107 }
108 
109 static void au1x_pcm_queue_rx(struct au1xpsc_audio_dmadata *cd)
110 {
111 	au1xxx_dbdma_put_dest(cd->ddma_chan, cd->dma_area,
112 			      cd->period_bytes, DDMA_FLAGS_IE);
113 
114 	/* update next-to-queue period */
115 	++cd->q_period;
116 	cd->dma_area += cd->period_bytes;
117 	if (cd->q_period >= cd->periods) {
118 		cd->q_period = 0;
119 		cd->dma_area = cd->dma_area_s;
120 	}
121 }
122 
123 static void au1x_pcm_dmatx_cb(int irq, void *dev_id)
124 {
125 	struct au1xpsc_audio_dmadata *cd = dev_id;
126 
127 	cd->pos += cd->period_bytes;
128 	if (++cd->curr_period >= cd->periods) {
129 		cd->pos = 0;
130 		cd->curr_period = 0;
131 	}
132 	snd_pcm_period_elapsed(cd->substream);
133 	au1x_pcm_queue_tx(cd);
134 }
135 
136 static void au1x_pcm_dmarx_cb(int irq, void *dev_id)
137 {
138 	struct au1xpsc_audio_dmadata *cd = dev_id;
139 
140 	cd->pos += cd->period_bytes;
141 	if (++cd->curr_period >= cd->periods) {
142 		cd->pos = 0;
143 		cd->curr_period = 0;
144 	}
145 	snd_pcm_period_elapsed(cd->substream);
146 	au1x_pcm_queue_rx(cd);
147 }
148 
149 static void au1x_pcm_dbdma_free(struct au1xpsc_audio_dmadata *pcd)
150 {
151 	if (pcd->ddma_chan) {
152 		au1xxx_dbdma_stop(pcd->ddma_chan);
153 		au1xxx_dbdma_reset(pcd->ddma_chan);
154 		au1xxx_dbdma_chan_free(pcd->ddma_chan);
155 		pcd->ddma_chan = 0;
156 		pcd->msbits = 0;
157 	}
158 }
159 
160 /* in case of missing DMA ring or changed TX-source / RX-dest bit widths,
161  * allocate (or reallocate) a 2-descriptor DMA ring with bit depth according
162  * to ALSA-supplied sample depth.  This is due to limitations in the dbdma api
163  * (cannot adjust source/dest widths of already allocated descriptor ring).
164  */
165 static int au1x_pcm_dbdma_realloc(struct au1xpsc_audio_dmadata *pcd,
166 				 int stype, int msbits)
167 {
168 	/* DMA only in 8/16/32 bit widths */
169 	if (msbits == 24)
170 		msbits = 32;
171 
172 	/* check current config: correct bits and descriptors allocated? */
173 	if ((pcd->ddma_chan) && (msbits == pcd->msbits))
174 		goto out;	/* all ok! */
175 
176 	au1x_pcm_dbdma_free(pcd);
177 
178 	if (stype == PCM_RX)
179 		pcd->ddma_chan = au1xxx_dbdma_chan_alloc(pcd->ddma_id,
180 					DSCR_CMD0_ALWAYS,
181 					au1x_pcm_dmarx_cb, (void *)pcd);
182 	else
183 		pcd->ddma_chan = au1xxx_dbdma_chan_alloc(DSCR_CMD0_ALWAYS,
184 					pcd->ddma_id,
185 					au1x_pcm_dmatx_cb, (void *)pcd);
186 
187 	if (!pcd->ddma_chan)
188 		return -ENOMEM;
189 
190 	au1xxx_dbdma_set_devwidth(pcd->ddma_chan, msbits);
191 	au1xxx_dbdma_ring_alloc(pcd->ddma_chan, 2);
192 
193 	pcd->msbits = msbits;
194 
195 	au1xxx_dbdma_stop(pcd->ddma_chan);
196 	au1xxx_dbdma_reset(pcd->ddma_chan);
197 
198 out:
199 	return 0;
200 }
201 
202 static int au1xpsc_pcm_hw_params(struct snd_pcm_substream *substream,
203 				 struct snd_pcm_hw_params *params)
204 {
205 	struct snd_pcm_runtime *runtime = substream->runtime;
206 	struct au1xpsc_audio_dmadata *pcd;
207 	int stype, ret;
208 
209 	ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
210 	if (ret < 0)
211 		goto out;
212 
213 	stype = SUBSTREAM_TYPE(substream);
214 	pcd = au1xpsc_audio_pcmdma[stype];
215 
216 	DBG("runtime->dma_area = 0x%08lx dma_addr_t = 0x%08lx dma_size = %d "
217 	    "runtime->min_align %d\n",
218 		(unsigned long)runtime->dma_area,
219 		(unsigned long)runtime->dma_addr, runtime->dma_bytes,
220 		runtime->min_align);
221 
222 	DBG("bits %d  frags %d  frag_bytes %d  is_rx %d\n", params->msbits,
223 		params_periods(params), params_period_bytes(params), stype);
224 
225 	ret = au1x_pcm_dbdma_realloc(pcd, stype, params->msbits);
226 	if (ret) {
227 		MSG("DDMA channel (re)alloc failed!\n");
228 		goto out;
229 	}
230 
231 	pcd->substream = substream;
232 	pcd->period_bytes = params_period_bytes(params);
233 	pcd->periods = params_periods(params);
234 	pcd->dma_area_s = pcd->dma_area = runtime->dma_addr;
235 	pcd->q_period = 0;
236 	pcd->curr_period = 0;
237 	pcd->pos = 0;
238 
239 	ret = 0;
240 out:
241 	return ret;
242 }
243 
244 static int au1xpsc_pcm_hw_free(struct snd_pcm_substream *substream)
245 {
246 	snd_pcm_lib_free_pages(substream);
247 	return 0;
248 }
249 
250 static int au1xpsc_pcm_prepare(struct snd_pcm_substream *substream)
251 {
252 	struct au1xpsc_audio_dmadata *pcd =
253 			au1xpsc_audio_pcmdma[SUBSTREAM_TYPE(substream)];
254 
255 	au1xxx_dbdma_reset(pcd->ddma_chan);
256 
257 	if (SUBSTREAM_TYPE(substream) == PCM_RX) {
258 		au1x_pcm_queue_rx(pcd);
259 		au1x_pcm_queue_rx(pcd);
260 	} else {
261 		au1x_pcm_queue_tx(pcd);
262 		au1x_pcm_queue_tx(pcd);
263 	}
264 
265 	return 0;
266 }
267 
268 static int au1xpsc_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
269 {
270 	u32 c = au1xpsc_audio_pcmdma[SUBSTREAM_TYPE(substream)]->ddma_chan;
271 
272 	switch (cmd) {
273 	case SNDRV_PCM_TRIGGER_START:
274 	case SNDRV_PCM_TRIGGER_RESUME:
275 		au1xxx_dbdma_start(c);
276 		break;
277 	case SNDRV_PCM_TRIGGER_STOP:
278 	case SNDRV_PCM_TRIGGER_SUSPEND:
279 		au1xxx_dbdma_stop(c);
280 		break;
281 	default:
282 		return -EINVAL;
283 	}
284 	return 0;
285 }
286 
287 static snd_pcm_uframes_t
288 au1xpsc_pcm_pointer(struct snd_pcm_substream *substream)
289 {
290 	return bytes_to_frames(substream->runtime,
291 		au1xpsc_audio_pcmdma[SUBSTREAM_TYPE(substream)]->pos);
292 }
293 
294 static int au1xpsc_pcm_open(struct snd_pcm_substream *substream)
295 {
296 	snd_soc_set_runtime_hwparams(substream, &au1xpsc_pcm_hardware);
297 	return 0;
298 }
299 
300 static int au1xpsc_pcm_close(struct snd_pcm_substream *substream)
301 {
302 	au1x_pcm_dbdma_free(au1xpsc_audio_pcmdma[SUBSTREAM_TYPE(substream)]);
303 	return 0;
304 }
305 
306 static struct snd_pcm_ops au1xpsc_pcm_ops = {
307 	.open		= au1xpsc_pcm_open,
308 	.close		= au1xpsc_pcm_close,
309 	.ioctl		= snd_pcm_lib_ioctl,
310 	.hw_params	= au1xpsc_pcm_hw_params,
311 	.hw_free	= au1xpsc_pcm_hw_free,
312 	.prepare	= au1xpsc_pcm_prepare,
313 	.trigger	= au1xpsc_pcm_trigger,
314 	.pointer	= au1xpsc_pcm_pointer,
315 };
316 
317 static void au1xpsc_pcm_free_dma_buffers(struct snd_pcm *pcm)
318 {
319 	snd_pcm_lib_preallocate_free_for_all(pcm);
320 }
321 
322 static int au1xpsc_pcm_new(struct snd_card *card,
323 			   struct snd_soc_dai *dai,
324 			   struct snd_pcm *pcm)
325 {
326 	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
327 		card->dev, AU1XPSC_BUFFER_MIN_BYTES, (4096 * 1024) - 1);
328 
329 	return 0;
330 }
331 
332 static int au1xpsc_pcm_probe(struct platform_device *pdev)
333 {
334 	if (!au1xpsc_audio_pcmdma[PCM_TX] || !au1xpsc_audio_pcmdma[PCM_RX])
335 		return -ENODEV;
336 
337 	return 0;
338 }
339 
340 static int au1xpsc_pcm_remove(struct platform_device *pdev)
341 {
342 	return 0;
343 }
344 
345 /* au1xpsc audio platform */
346 struct snd_soc_platform au1xpsc_soc_platform = {
347 	.name		= "au1xpsc-pcm-dbdma",
348 	.probe		= au1xpsc_pcm_probe,
349 	.remove		= au1xpsc_pcm_remove,
350 	.pcm_ops 	= &au1xpsc_pcm_ops,
351 	.pcm_new	= au1xpsc_pcm_new,
352 	.pcm_free	= au1xpsc_pcm_free_dma_buffers,
353 };
354 EXPORT_SYMBOL_GPL(au1xpsc_soc_platform);
355 
356 static int __devinit au1xpsc_pcm_drvprobe(struct platform_device *pdev)
357 {
358 	struct resource *r;
359 	int ret;
360 
361 	if (au1xpsc_audio_pcmdma[PCM_TX] || au1xpsc_audio_pcmdma[PCM_RX])
362 		return -EBUSY;
363 
364 	/* TX DMA */
365 	au1xpsc_audio_pcmdma[PCM_TX]
366 		= kzalloc(sizeof(struct au1xpsc_audio_dmadata), GFP_KERNEL);
367 	if (!au1xpsc_audio_pcmdma[PCM_TX])
368 		return -ENOMEM;
369 
370 	r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
371 	if (!r) {
372 		ret = -ENODEV;
373 		goto out1;
374 	}
375 	(au1xpsc_audio_pcmdma[PCM_TX])->ddma_id = r->start;
376 
377 	/* RX DMA */
378 	au1xpsc_audio_pcmdma[PCM_RX]
379 		= kzalloc(sizeof(struct au1xpsc_audio_dmadata), GFP_KERNEL);
380 	if (!au1xpsc_audio_pcmdma[PCM_RX])
381 		return -ENOMEM;
382 
383 	r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
384 	if (!r) {
385 		ret = -ENODEV;
386 		goto out2;
387 	}
388 	(au1xpsc_audio_pcmdma[PCM_RX])->ddma_id = r->start;
389 
390 	ret = snd_soc_register_platform(&au1xpsc_soc_platform);
391 	if (!ret)
392 		return ret;
393 
394 out2:
395 	kfree(au1xpsc_audio_pcmdma[PCM_RX]);
396 	au1xpsc_audio_pcmdma[PCM_RX] = NULL;
397 out1:
398 	kfree(au1xpsc_audio_pcmdma[PCM_TX]);
399 	au1xpsc_audio_pcmdma[PCM_TX] = NULL;
400 	return ret;
401 }
402 
403 static int __devexit au1xpsc_pcm_drvremove(struct platform_device *pdev)
404 {
405 	int i;
406 
407 	snd_soc_unregister_platform(&au1xpsc_soc_platform);
408 
409 	for (i = 0; i < 2; i++) {
410 		if (au1xpsc_audio_pcmdma[i]) {
411 			au1x_pcm_dbdma_free(au1xpsc_audio_pcmdma[i]);
412 			kfree(au1xpsc_audio_pcmdma[i]);
413 			au1xpsc_audio_pcmdma[i] = NULL;
414 		}
415 	}
416 
417 	return 0;
418 }
419 
420 static struct platform_driver au1xpsc_pcm_driver = {
421 	.driver	= {
422 		.name	= "au1xpsc-pcm",
423 		.owner	= THIS_MODULE,
424 	},
425 	.probe		= au1xpsc_pcm_drvprobe,
426 	.remove		= __devexit_p(au1xpsc_pcm_drvremove),
427 };
428 
429 static int __init au1xpsc_audio_dbdma_load(void)
430 {
431 	au1xpsc_audio_pcmdma[PCM_TX] = NULL;
432 	au1xpsc_audio_pcmdma[PCM_RX] = NULL;
433 	return platform_driver_register(&au1xpsc_pcm_driver);
434 }
435 
436 static void __exit au1xpsc_audio_dbdma_unload(void)
437 {
438 	platform_driver_unregister(&au1xpsc_pcm_driver);
439 }
440 
441 module_init(au1xpsc_audio_dbdma_load);
442 module_exit(au1xpsc_audio_dbdma_unload);
443 
444 
445 struct platform_device *au1xpsc_pcm_add(struct platform_device *pdev)
446 {
447 	struct resource *res, *r;
448 	struct platform_device *pd;
449 	int id[2];
450 	int ret;
451 
452 	r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
453 	if (!r)
454 		return NULL;
455 	id[0] = r->start;
456 
457 	r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
458 	if (!r)
459 		return NULL;
460 	id[1] = r->start;
461 
462 	res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
463 	if (!res)
464 		return NULL;
465 
466 	res[0].start = res[0].end = id[0];
467 	res[1].start = res[1].end = id[1];
468 	res[0].flags = res[1].flags = IORESOURCE_DMA;
469 
470 	pd = platform_device_alloc("au1xpsc-pcm", -1);
471 	if (!pd)
472 		goto out;
473 
474 	pd->resource = res;
475 	pd->num_resources = 2;
476 
477 	ret = platform_device_add(pd);
478 	if (!ret)
479 		return pd;
480 
481 	platform_device_put(pd);
482 out:
483 	kfree(res);
484 	return NULL;
485 }
486 EXPORT_SYMBOL_GPL(au1xpsc_pcm_add);
487 
488 void au1xpsc_pcm_destroy(struct platform_device *dmapd)
489 {
490 	if (dmapd)
491 		platform_device_unregister(dmapd);
492 }
493 EXPORT_SYMBOL_GPL(au1xpsc_pcm_destroy);
494 
495 MODULE_LICENSE("GPL");
496 MODULE_DESCRIPTION("Au12x0/Au1550 PSC Audio DMA driver");
497 MODULE_AUTHOR("Manuel Lauss");
498