xref: /linux/sound/soc/au1x/dbdma2.c (revision 958e792c7c8f06a9e666adb0ed94fff2cf90156f)
1 /*
2  * Au12x0/Au1550 PSC ALSA ASoC audio support.
3  *
4  * (c) 2007-2008 MSC Vertriebsges.m.b.H.,
5  *	Manuel Lauss <mano@roarinelk.homelinux.net>
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 	unsigned long dma_area;		/* address of queued DMA area */
55 	unsigned long 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,
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_flags(cd->ddma_chan,
98 				(void *)phys_to_virt(cd->dma_area),
99 				cd->period_bytes, DDMA_FLAGS_IE);
100 
101 	/* update next-to-queue period */
102 	++cd->q_period;
103 	cd->dma_area += cd->period_bytes;
104 	if (cd->q_period >= cd->periods) {
105 		cd->q_period = 0;
106 		cd->dma_area = cd->dma_area_s;
107 	}
108 }
109 
110 static void au1x_pcm_queue_rx(struct au1xpsc_audio_dmadata *cd)
111 {
112 	au1xxx_dbdma_put_dest_flags(cd->ddma_chan,
113 				(void *)phys_to_virt(cd->dma_area),
114 				cd->period_bytes, DDMA_FLAGS_IE);
115 
116 	/* update next-to-queue period */
117 	++cd->q_period;
118 	cd->dma_area += cd->period_bytes;
119 	if (cd->q_period >= cd->periods) {
120 		cd->q_period = 0;
121 		cd->dma_area = cd->dma_area_s;
122 	}
123 }
124 
125 static void au1x_pcm_dmatx_cb(int irq, void *dev_id)
126 {
127 	struct au1xpsc_audio_dmadata *cd = dev_id;
128 
129 	cd->pos += cd->period_bytes;
130 	if (++cd->curr_period >= cd->periods) {
131 		cd->pos = 0;
132 		cd->curr_period = 0;
133 	}
134 	snd_pcm_period_elapsed(cd->substream);
135 	au1x_pcm_queue_tx(cd);
136 }
137 
138 static void au1x_pcm_dmarx_cb(int irq, void *dev_id)
139 {
140 	struct au1xpsc_audio_dmadata *cd = dev_id;
141 
142 	cd->pos += cd->period_bytes;
143 	if (++cd->curr_period >= cd->periods) {
144 		cd->pos = 0;
145 		cd->curr_period = 0;
146 	}
147 	snd_pcm_period_elapsed(cd->substream);
148 	au1x_pcm_queue_rx(cd);
149 }
150 
151 static void au1x_pcm_dbdma_free(struct au1xpsc_audio_dmadata *pcd)
152 {
153 	if (pcd->ddma_chan) {
154 		au1xxx_dbdma_stop(pcd->ddma_chan);
155 		au1xxx_dbdma_reset(pcd->ddma_chan);
156 		au1xxx_dbdma_chan_free(pcd->ddma_chan);
157 		pcd->ddma_chan = 0;
158 		pcd->msbits = 0;
159 	}
160 }
161 
162 /* in case of missing DMA ring or changed TX-source / RX-dest bit widths,
163  * allocate (or reallocate) a 2-descriptor DMA ring with bit depth according
164  * to ALSA-supplied sample depth.  This is due to limitations in the dbdma api
165  * (cannot adjust source/dest widths of already allocated descriptor ring).
166  */
167 static int au1x_pcm_dbdma_realloc(struct au1xpsc_audio_dmadata *pcd,
168 				 int stype, int msbits)
169 {
170 	/* DMA only in 8/16/32 bit widths */
171 	if (msbits == 24)
172 		msbits = 32;
173 
174 	/* check current config: correct bits and descriptors allocated? */
175 	if ((pcd->ddma_chan) && (msbits == pcd->msbits))
176 		goto out;	/* all ok! */
177 
178 	au1x_pcm_dbdma_free(pcd);
179 
180 	if (stype == PCM_RX)
181 		pcd->ddma_chan = au1xxx_dbdma_chan_alloc(pcd->ddma_id,
182 					DSCR_CMD0_ALWAYS,
183 					au1x_pcm_dmarx_cb, (void *)pcd);
184 	else
185 		pcd->ddma_chan = au1xxx_dbdma_chan_alloc(DSCR_CMD0_ALWAYS,
186 					pcd->ddma_id,
187 					au1x_pcm_dmatx_cb, (void *)pcd);
188 
189 	if (!pcd->ddma_chan)
190 		return -ENOMEM;;
191 
192 	au1xxx_dbdma_set_devwidth(pcd->ddma_chan, msbits);
193 	au1xxx_dbdma_ring_alloc(pcd->ddma_chan, 2);
194 
195 	pcd->msbits = msbits;
196 
197 	au1xxx_dbdma_stop(pcd->ddma_chan);
198 	au1xxx_dbdma_reset(pcd->ddma_chan);
199 
200 out:
201 	return 0;
202 }
203 
204 static int au1xpsc_pcm_hw_params(struct snd_pcm_substream *substream,
205 				 struct snd_pcm_hw_params *params)
206 {
207 	struct snd_pcm_runtime *runtime = substream->runtime;
208 	struct au1xpsc_audio_dmadata *pcd;
209 	int stype, ret;
210 
211 	ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
212 	if (ret < 0)
213 		goto out;
214 
215 	stype = SUBSTREAM_TYPE(substream);
216 	pcd = au1xpsc_audio_pcmdma[stype];
217 
218 	DBG("runtime->dma_area = 0x%08lx dma_addr_t = 0x%08lx dma_size = %d "
219 	    "runtime->min_align %d\n",
220 		(unsigned long)runtime->dma_area,
221 		(unsigned long)runtime->dma_addr, runtime->dma_bytes,
222 		runtime->min_align);
223 
224 	DBG("bits %d  frags %d  frag_bytes %d  is_rx %d\n", params->msbits,
225 		params_periods(params), params_period_bytes(params), stype);
226 
227 	ret = au1x_pcm_dbdma_realloc(pcd, stype, params->msbits);
228 	if (ret) {
229 		MSG("DDMA channel (re)alloc failed!\n");
230 		goto out;
231 	}
232 
233 	pcd->substream = substream;
234 	pcd->period_bytes = params_period_bytes(params);
235 	pcd->periods = params_periods(params);
236 	pcd->dma_area_s = pcd->dma_area = (unsigned long)runtime->dma_addr;
237 	pcd->q_period = 0;
238 	pcd->curr_period = 0;
239 	pcd->pos = 0;
240 
241 	ret = 0;
242 out:
243 	return ret;
244 }
245 
246 static int au1xpsc_pcm_hw_free(struct snd_pcm_substream *substream)
247 {
248 	snd_pcm_lib_free_pages(substream);
249 	return 0;
250 }
251 
252 static int au1xpsc_pcm_prepare(struct snd_pcm_substream *substream)
253 {
254 	struct au1xpsc_audio_dmadata *pcd =
255 			au1xpsc_audio_pcmdma[SUBSTREAM_TYPE(substream)];
256 
257 	au1xxx_dbdma_reset(pcd->ddma_chan);
258 
259 	if (SUBSTREAM_TYPE(substream) == PCM_RX) {
260 		au1x_pcm_queue_rx(pcd);
261 		au1x_pcm_queue_rx(pcd);
262 	} else {
263 		au1x_pcm_queue_tx(pcd);
264 		au1x_pcm_queue_tx(pcd);
265 	}
266 
267 	return 0;
268 }
269 
270 static int au1xpsc_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
271 {
272 	u32 c = au1xpsc_audio_pcmdma[SUBSTREAM_TYPE(substream)]->ddma_chan;
273 
274 	switch (cmd) {
275 	case SNDRV_PCM_TRIGGER_START:
276 	case SNDRV_PCM_TRIGGER_RESUME:
277 		au1xxx_dbdma_start(c);
278 		break;
279 	case SNDRV_PCM_TRIGGER_STOP:
280 	case SNDRV_PCM_TRIGGER_SUSPEND:
281 		au1xxx_dbdma_stop(c);
282 		break;
283 	default:
284 		return -EINVAL;
285 	}
286 	return 0;
287 }
288 
289 static snd_pcm_uframes_t
290 au1xpsc_pcm_pointer(struct snd_pcm_substream *substream)
291 {
292 	return bytes_to_frames(substream->runtime,
293 		au1xpsc_audio_pcmdma[SUBSTREAM_TYPE(substream)]->pos);
294 }
295 
296 static int au1xpsc_pcm_open(struct snd_pcm_substream *substream)
297 {
298 	snd_soc_set_runtime_hwparams(substream, &au1xpsc_pcm_hardware);
299 	return 0;
300 }
301 
302 static int au1xpsc_pcm_close(struct snd_pcm_substream *substream)
303 {
304 	au1x_pcm_dbdma_free(au1xpsc_audio_pcmdma[SUBSTREAM_TYPE(substream)]);
305 	return 0;
306 }
307 
308 struct snd_pcm_ops au1xpsc_pcm_ops = {
309 	.open		= au1xpsc_pcm_open,
310 	.close		= au1xpsc_pcm_close,
311 	.ioctl		= snd_pcm_lib_ioctl,
312 	.hw_params	= au1xpsc_pcm_hw_params,
313 	.hw_free	= au1xpsc_pcm_hw_free,
314 	.prepare	= au1xpsc_pcm_prepare,
315 	.trigger	= au1xpsc_pcm_trigger,
316 	.pointer	= au1xpsc_pcm_pointer,
317 };
318 
319 static void au1xpsc_pcm_free_dma_buffers(struct snd_pcm *pcm)
320 {
321 	snd_pcm_lib_preallocate_free_for_all(pcm);
322 }
323 
324 static int au1xpsc_pcm_new(struct snd_card *card,
325 			   struct snd_soc_dai *dai,
326 			   struct snd_pcm *pcm)
327 {
328 	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
329 		card->dev, AU1XPSC_BUFFER_MIN_BYTES, (4096 * 1024) - 1);
330 
331 	return 0;
332 }
333 
334 static int au1xpsc_pcm_probe(struct platform_device *pdev)
335 {
336 	struct resource *r;
337 	int ret;
338 
339 	if (au1xpsc_audio_pcmdma[PCM_TX] || au1xpsc_audio_pcmdma[PCM_RX])
340 		return -EBUSY;
341 
342 	/* TX DMA */
343 	au1xpsc_audio_pcmdma[PCM_TX]
344 		= kzalloc(sizeof(struct au1xpsc_audio_dmadata), GFP_KERNEL);
345 	if (!au1xpsc_audio_pcmdma[PCM_TX])
346 		return -ENOMEM;
347 
348 	r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
349 	if (!r) {
350 		ret = -ENODEV;
351 		goto out1;
352 	}
353 	(au1xpsc_audio_pcmdma[PCM_TX])->ddma_id = r->start;
354 
355 	/* RX DMA */
356 	au1xpsc_audio_pcmdma[PCM_RX]
357 		= kzalloc(sizeof(struct au1xpsc_audio_dmadata), GFP_KERNEL);
358 	if (!au1xpsc_audio_pcmdma[PCM_RX])
359 		return -ENOMEM;
360 
361 	r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
362 	if (!r) {
363 		ret = -ENODEV;
364 		goto out2;
365 	}
366 	(au1xpsc_audio_pcmdma[PCM_RX])->ddma_id = r->start;
367 
368 	return 0;
369 
370 out2:
371 	kfree(au1xpsc_audio_pcmdma[PCM_RX]);
372 	au1xpsc_audio_pcmdma[PCM_RX] = NULL;
373 out1:
374 	kfree(au1xpsc_audio_pcmdma[PCM_TX]);
375 	au1xpsc_audio_pcmdma[PCM_TX] = NULL;
376 	return ret;
377 }
378 
379 static int au1xpsc_pcm_remove(struct platform_device *pdev)
380 {
381 	int i;
382 
383 	for (i = 0; i < 2; i++) {
384 		if (au1xpsc_audio_pcmdma[i]) {
385 			au1x_pcm_dbdma_free(au1xpsc_audio_pcmdma[i]);
386 			kfree(au1xpsc_audio_pcmdma[i]);
387 			au1xpsc_audio_pcmdma[i] = NULL;
388 		}
389 	}
390 
391 	return 0;
392 }
393 
394 /* au1xpsc audio platform */
395 struct snd_soc_platform au1xpsc_soc_platform = {
396 	.name		= "au1xpsc-pcm-dbdma",
397 	.probe		= au1xpsc_pcm_probe,
398 	.remove		= au1xpsc_pcm_remove,
399 	.pcm_ops 	= &au1xpsc_pcm_ops,
400 	.pcm_new	= au1xpsc_pcm_new,
401 	.pcm_free	= au1xpsc_pcm_free_dma_buffers,
402 };
403 EXPORT_SYMBOL_GPL(au1xpsc_soc_platform);
404 
405 static int __init au1xpsc_audio_dbdma_init(void)
406 {
407 	au1xpsc_audio_pcmdma[PCM_TX] = NULL;
408 	au1xpsc_audio_pcmdma[PCM_RX] = NULL;
409 	return snd_soc_register_platform(&au1xpsc_soc_platform);
410 }
411 
412 static void __exit au1xpsc_audio_dbdma_exit(void)
413 {
414 	snd_soc_unregister_platform(&au1xpsc_soc_platform);
415 }
416 
417 module_init(au1xpsc_audio_dbdma_init);
418 module_exit(au1xpsc_audio_dbdma_exit);
419 
420 MODULE_LICENSE("GPL");
421 MODULE_DESCRIPTION("Au12x0/Au1550 PSC Audio DMA driver");
422 MODULE_AUTHOR("Manuel Lauss <mano@roarinelk.homelinux.net>");
423