1/*
2 * omap-mcpdm.c  --  OMAP ALSA SoC DAI driver using McPDM port
3 *
4 * Copyright (C) 2009 - 2011 Texas Instruments
5 *
6 * Author: Misael Lopez Cruz <misael.lopez@ti.com>
7 * Contact: Jorge Eduardo Candelaria <x0107209@ti.com>
8 *          Margarita Olaya <magi.olaya@ti.com>
9 *          Peter Ujfalusi <peter.ujfalusi@ti.com>
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * version 2 as published by the Free Software Foundation.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
23 * 02110-1301 USA
24 *
25 */
26
27#include <linux/init.h>
28#include <linux/module.h>
29#include <linux/platform_device.h>
30#include <linux/interrupt.h>
31#include <linux/err.h>
32#include <linux/io.h>
33#include <linux/irq.h>
34#include <linux/slab.h>
35#include <linux/pm_runtime.h>
36#include <linux/of_device.h>
37
38#include <sound/core.h>
39#include <sound/pcm.h>
40#include <sound/pcm_params.h>
41#include <sound/soc.h>
42#include <sound/dmaengine_pcm.h>
43#include <sound/omap-pcm.h>
44
45#include "omap-mcpdm.h"
46
47struct mcpdm_link_config {
48	u32 link_mask; /* channel mask for the direction */
49	u32 threshold; /* FIFO threshold */
50};
51
52struct omap_mcpdm {
53	struct device *dev;
54	unsigned long phys_base;
55	void __iomem *io_base;
56	int irq;
57
58	struct mutex mutex;
59
60	/* Playback/Capture configuration */
61	struct mcpdm_link_config config[2];
62
63	/* McPDM dn offsets for rx1, and 2 channels */
64	u32 dn_rx_offset;
65
66	/* McPDM needs to be restarted due to runtime reconfiguration */
67	bool restart;
68
69	struct snd_dmaengine_dai_dma_data dma_data[2];
70};
71
72/*
73 * Stream DMA parameters
74 */
75
76static inline void omap_mcpdm_write(struct omap_mcpdm *mcpdm, u16 reg, u32 val)
77{
78	writel_relaxed(val, mcpdm->io_base + reg);
79}
80
81static inline int omap_mcpdm_read(struct omap_mcpdm *mcpdm, u16 reg)
82{
83	return readl_relaxed(mcpdm->io_base + reg);
84}
85
86#ifdef DEBUG
87static void omap_mcpdm_reg_dump(struct omap_mcpdm *mcpdm)
88{
89	dev_dbg(mcpdm->dev, "***********************\n");
90	dev_dbg(mcpdm->dev, "IRQSTATUS_RAW:  0x%04x\n",
91			omap_mcpdm_read(mcpdm, MCPDM_REG_IRQSTATUS_RAW));
92	dev_dbg(mcpdm->dev, "IRQSTATUS:  0x%04x\n",
93			omap_mcpdm_read(mcpdm, MCPDM_REG_IRQSTATUS));
94	dev_dbg(mcpdm->dev, "IRQENABLE_SET:  0x%04x\n",
95			omap_mcpdm_read(mcpdm, MCPDM_REG_IRQENABLE_SET));
96	dev_dbg(mcpdm->dev, "IRQENABLE_CLR:  0x%04x\n",
97			omap_mcpdm_read(mcpdm, MCPDM_REG_IRQENABLE_CLR));
98	dev_dbg(mcpdm->dev, "IRQWAKE_EN: 0x%04x\n",
99			omap_mcpdm_read(mcpdm, MCPDM_REG_IRQWAKE_EN));
100	dev_dbg(mcpdm->dev, "DMAENABLE_SET: 0x%04x\n",
101			omap_mcpdm_read(mcpdm, MCPDM_REG_DMAENABLE_SET));
102	dev_dbg(mcpdm->dev, "DMAENABLE_CLR:  0x%04x\n",
103			omap_mcpdm_read(mcpdm, MCPDM_REG_DMAENABLE_CLR));
104	dev_dbg(mcpdm->dev, "DMAWAKEEN:  0x%04x\n",
105			omap_mcpdm_read(mcpdm, MCPDM_REG_DMAWAKEEN));
106	dev_dbg(mcpdm->dev, "CTRL:  0x%04x\n",
107			omap_mcpdm_read(mcpdm, MCPDM_REG_CTRL));
108	dev_dbg(mcpdm->dev, "DN_DATA:  0x%04x\n",
109			omap_mcpdm_read(mcpdm, MCPDM_REG_DN_DATA));
110	dev_dbg(mcpdm->dev, "UP_DATA: 0x%04x\n",
111			omap_mcpdm_read(mcpdm, MCPDM_REG_UP_DATA));
112	dev_dbg(mcpdm->dev, "FIFO_CTRL_DN: 0x%04x\n",
113			omap_mcpdm_read(mcpdm, MCPDM_REG_FIFO_CTRL_DN));
114	dev_dbg(mcpdm->dev, "FIFO_CTRL_UP:  0x%04x\n",
115			omap_mcpdm_read(mcpdm, MCPDM_REG_FIFO_CTRL_UP));
116	dev_dbg(mcpdm->dev, "***********************\n");
117}
118#else
119static void omap_mcpdm_reg_dump(struct omap_mcpdm *mcpdm) {}
120#endif
121
122/*
123 * Enables the transfer through the PDM interface to/from the Phoenix
124 * codec by enabling the corresponding UP or DN channels.
125 */
126static void omap_mcpdm_start(struct omap_mcpdm *mcpdm)
127{
128	u32 ctrl = omap_mcpdm_read(mcpdm, MCPDM_REG_CTRL);
129	u32 link_mask = mcpdm->config[0].link_mask | mcpdm->config[1].link_mask;
130
131	ctrl |= (MCPDM_SW_DN_RST | MCPDM_SW_UP_RST);
132	omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl);
133
134	ctrl |= link_mask;
135	omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl);
136
137	ctrl &= ~(MCPDM_SW_DN_RST | MCPDM_SW_UP_RST);
138	omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl);
139}
140
141/*
142 * Disables the transfer through the PDM interface to/from the Phoenix
143 * codec by disabling the corresponding UP or DN channels.
144 */
145static void omap_mcpdm_stop(struct omap_mcpdm *mcpdm)
146{
147	u32 ctrl = omap_mcpdm_read(mcpdm, MCPDM_REG_CTRL);
148	u32 link_mask = MCPDM_PDM_DN_MASK | MCPDM_PDM_UP_MASK;
149
150	ctrl |= (MCPDM_SW_DN_RST | MCPDM_SW_UP_RST);
151	omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl);
152
153	ctrl &= ~(link_mask);
154	omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl);
155
156	ctrl &= ~(MCPDM_SW_DN_RST | MCPDM_SW_UP_RST);
157	omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl);
158
159}
160
161/*
162 * Is the physical McPDM interface active.
163 */
164static inline int omap_mcpdm_active(struct omap_mcpdm *mcpdm)
165{
166	return omap_mcpdm_read(mcpdm, MCPDM_REG_CTRL) &
167					(MCPDM_PDM_DN_MASK | MCPDM_PDM_UP_MASK);
168}
169
170/*
171 * Configures McPDM uplink, and downlink for audio.
172 * This function should be called before omap_mcpdm_start.
173 */
174static void omap_mcpdm_open_streams(struct omap_mcpdm *mcpdm)
175{
176	omap_mcpdm_write(mcpdm, MCPDM_REG_IRQENABLE_SET,
177			MCPDM_DN_IRQ_EMPTY | MCPDM_DN_IRQ_FULL |
178			MCPDM_UP_IRQ_EMPTY | MCPDM_UP_IRQ_FULL);
179
180	/* Enable DN RX1/2 offset cancellation feature, if configured */
181	if (mcpdm->dn_rx_offset) {
182		u32 dn_offset = mcpdm->dn_rx_offset;
183
184		omap_mcpdm_write(mcpdm, MCPDM_REG_DN_OFFSET, dn_offset);
185		dn_offset |= (MCPDM_DN_OFST_RX1_EN | MCPDM_DN_OFST_RX2_EN);
186		omap_mcpdm_write(mcpdm, MCPDM_REG_DN_OFFSET, dn_offset);
187	}
188
189	omap_mcpdm_write(mcpdm, MCPDM_REG_FIFO_CTRL_DN,
190			 mcpdm->config[SNDRV_PCM_STREAM_PLAYBACK].threshold);
191	omap_mcpdm_write(mcpdm, MCPDM_REG_FIFO_CTRL_UP,
192			 mcpdm->config[SNDRV_PCM_STREAM_CAPTURE].threshold);
193
194	omap_mcpdm_write(mcpdm, MCPDM_REG_DMAENABLE_SET,
195			MCPDM_DMA_DN_ENABLE | MCPDM_DMA_UP_ENABLE);
196}
197
198/*
199 * Cleans McPDM uplink, and downlink configuration.
200 * This function should be called when the stream is closed.
201 */
202static void omap_mcpdm_close_streams(struct omap_mcpdm *mcpdm)
203{
204	/* Disable irq request generation for downlink */
205	omap_mcpdm_write(mcpdm, MCPDM_REG_IRQENABLE_CLR,
206			MCPDM_DN_IRQ_EMPTY | MCPDM_DN_IRQ_FULL);
207
208	/* Disable DMA request generation for downlink */
209	omap_mcpdm_write(mcpdm, MCPDM_REG_DMAENABLE_CLR, MCPDM_DMA_DN_ENABLE);
210
211	/* Disable irq request generation for uplink */
212	omap_mcpdm_write(mcpdm, MCPDM_REG_IRQENABLE_CLR,
213			MCPDM_UP_IRQ_EMPTY | MCPDM_UP_IRQ_FULL);
214
215	/* Disable DMA request generation for uplink */
216	omap_mcpdm_write(mcpdm, MCPDM_REG_DMAENABLE_CLR, MCPDM_DMA_UP_ENABLE);
217
218	/* Disable RX1/2 offset cancellation */
219	if (mcpdm->dn_rx_offset)
220		omap_mcpdm_write(mcpdm, MCPDM_REG_DN_OFFSET, 0);
221}
222
223static irqreturn_t omap_mcpdm_irq_handler(int irq, void *dev_id)
224{
225	struct omap_mcpdm *mcpdm = dev_id;
226	int irq_status;
227
228	irq_status = omap_mcpdm_read(mcpdm, MCPDM_REG_IRQSTATUS);
229
230	/* Acknowledge irq event */
231	omap_mcpdm_write(mcpdm, MCPDM_REG_IRQSTATUS, irq_status);
232
233	if (irq_status & MCPDM_DN_IRQ_FULL)
234		dev_dbg(mcpdm->dev, "DN (playback) FIFO Full\n");
235
236	if (irq_status & MCPDM_DN_IRQ_EMPTY)
237		dev_dbg(mcpdm->dev, "DN (playback) FIFO Empty\n");
238
239	if (irq_status & MCPDM_DN_IRQ)
240		dev_dbg(mcpdm->dev, "DN (playback) write request\n");
241
242	if (irq_status & MCPDM_UP_IRQ_FULL)
243		dev_dbg(mcpdm->dev, "UP (capture) FIFO Full\n");
244
245	if (irq_status & MCPDM_UP_IRQ_EMPTY)
246		dev_dbg(mcpdm->dev, "UP (capture) FIFO Empty\n");
247
248	if (irq_status & MCPDM_UP_IRQ)
249		dev_dbg(mcpdm->dev, "UP (capture) write request\n");
250
251	return IRQ_HANDLED;
252}
253
254static int omap_mcpdm_dai_startup(struct snd_pcm_substream *substream,
255				  struct snd_soc_dai *dai)
256{
257	struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(dai);
258
259	mutex_lock(&mcpdm->mutex);
260
261	if (!dai->active) {
262		u32 ctrl = omap_mcpdm_read(mcpdm, MCPDM_REG_CTRL);
263
264		omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, ctrl | MCPDM_WD_EN);
265		omap_mcpdm_open_streams(mcpdm);
266	}
267	mutex_unlock(&mcpdm->mutex);
268
269	return 0;
270}
271
272static void omap_mcpdm_dai_shutdown(struct snd_pcm_substream *substream,
273				  struct snd_soc_dai *dai)
274{
275	struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(dai);
276
277	mutex_lock(&mcpdm->mutex);
278
279	if (!dai->active) {
280		if (omap_mcpdm_active(mcpdm)) {
281			omap_mcpdm_stop(mcpdm);
282			omap_mcpdm_close_streams(mcpdm);
283			mcpdm->config[0].link_mask = 0;
284			mcpdm->config[1].link_mask = 0;
285		}
286	}
287
288	mutex_unlock(&mcpdm->mutex);
289}
290
291static int omap_mcpdm_dai_hw_params(struct snd_pcm_substream *substream,
292				    struct snd_pcm_hw_params *params,
293				    struct snd_soc_dai *dai)
294{
295	struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(dai);
296	int stream = substream->stream;
297	struct snd_dmaengine_dai_dma_data *dma_data;
298	u32 threshold;
299	int channels;
300	int link_mask = 0;
301
302	channels = params_channels(params);
303	switch (channels) {
304	case 5:
305		if (stream == SNDRV_PCM_STREAM_CAPTURE)
306			/* up to 3 channels for capture */
307			return -EINVAL;
308		link_mask |= 1 << 4;
309	case 4:
310		if (stream == SNDRV_PCM_STREAM_CAPTURE)
311			/* up to 3 channels for capture */
312			return -EINVAL;
313		link_mask |= 1 << 3;
314	case 3:
315		link_mask |= 1 << 2;
316	case 2:
317		link_mask |= 1 << 1;
318	case 1:
319		link_mask |= 1 << 0;
320		break;
321	default:
322		/* unsupported number of channels */
323		return -EINVAL;
324	}
325
326	dma_data = snd_soc_dai_get_dma_data(dai, substream);
327
328	threshold = mcpdm->config[stream].threshold;
329	/* Configure McPDM channels, and DMA packet size */
330	if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
331		link_mask <<= 3;
332
333		/* If capture is not running assume a stereo stream to come */
334		if (!mcpdm->config[!stream].link_mask)
335			mcpdm->config[!stream].link_mask = 0x3;
336
337		dma_data->maxburst =
338				(MCPDM_DN_THRES_MAX - threshold) * channels;
339	} else {
340		/* If playback is not running assume a stereo stream to come */
341		if (!mcpdm->config[!stream].link_mask)
342			mcpdm->config[!stream].link_mask = (0x3 << 3);
343
344		dma_data->maxburst = threshold * channels;
345	}
346
347	/* Check if we need to restart McPDM with this stream */
348	if (mcpdm->config[stream].link_mask &&
349	    mcpdm->config[stream].link_mask != link_mask)
350		mcpdm->restart = true;
351
352	mcpdm->config[stream].link_mask = link_mask;
353
354	return 0;
355}
356
357static int omap_mcpdm_prepare(struct snd_pcm_substream *substream,
358				  struct snd_soc_dai *dai)
359{
360	struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(dai);
361
362	if (!omap_mcpdm_active(mcpdm)) {
363		omap_mcpdm_start(mcpdm);
364		omap_mcpdm_reg_dump(mcpdm);
365	} else if (mcpdm->restart) {
366		omap_mcpdm_stop(mcpdm);
367		omap_mcpdm_start(mcpdm);
368		mcpdm->restart = false;
369		omap_mcpdm_reg_dump(mcpdm);
370	}
371
372	return 0;
373}
374
375static const struct snd_soc_dai_ops omap_mcpdm_dai_ops = {
376	.startup	= omap_mcpdm_dai_startup,
377	.shutdown	= omap_mcpdm_dai_shutdown,
378	.hw_params	= omap_mcpdm_dai_hw_params,
379	.prepare	= omap_mcpdm_prepare,
380};
381
382static int omap_mcpdm_probe(struct snd_soc_dai *dai)
383{
384	struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(dai);
385	int ret;
386
387	pm_runtime_enable(mcpdm->dev);
388
389	/* Disable lines while request is ongoing */
390	pm_runtime_get_sync(mcpdm->dev);
391	omap_mcpdm_write(mcpdm, MCPDM_REG_CTRL, 0x00);
392
393	ret = devm_request_irq(mcpdm->dev, mcpdm->irq, omap_mcpdm_irq_handler,
394				0, "McPDM", (void *)mcpdm);
395
396	pm_runtime_put_sync(mcpdm->dev);
397
398	if (ret) {
399		dev_err(mcpdm->dev, "Request for IRQ failed\n");
400		pm_runtime_disable(mcpdm->dev);
401	}
402
403	/* Configure McPDM threshold values */
404	mcpdm->config[SNDRV_PCM_STREAM_PLAYBACK].threshold = 2;
405	mcpdm->config[SNDRV_PCM_STREAM_CAPTURE].threshold =
406							MCPDM_UP_THRES_MAX - 3;
407
408	snd_soc_dai_init_dma_data(dai,
409				  &mcpdm->dma_data[SNDRV_PCM_STREAM_PLAYBACK],
410				  &mcpdm->dma_data[SNDRV_PCM_STREAM_CAPTURE]);
411
412	return ret;
413}
414
415static int omap_mcpdm_remove(struct snd_soc_dai *dai)
416{
417	struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(dai);
418
419	pm_runtime_disable(mcpdm->dev);
420
421	return 0;
422}
423
424#define OMAP_MCPDM_RATES	(SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000)
425#define OMAP_MCPDM_FORMATS	SNDRV_PCM_FMTBIT_S32_LE
426
427static struct snd_soc_dai_driver omap_mcpdm_dai = {
428	.probe = omap_mcpdm_probe,
429	.remove = omap_mcpdm_remove,
430	.probe_order = SND_SOC_COMP_ORDER_LATE,
431	.remove_order = SND_SOC_COMP_ORDER_EARLY,
432	.playback = {
433		.channels_min = 1,
434		.channels_max = 5,
435		.rates = OMAP_MCPDM_RATES,
436		.formats = OMAP_MCPDM_FORMATS,
437		.sig_bits = 24,
438	},
439	.capture = {
440		.channels_min = 1,
441		.channels_max = 3,
442		.rates = OMAP_MCPDM_RATES,
443		.formats = OMAP_MCPDM_FORMATS,
444		.sig_bits = 24,
445	},
446	.ops = &omap_mcpdm_dai_ops,
447};
448
449static const struct snd_soc_component_driver omap_mcpdm_component = {
450	.name		= "omap-mcpdm",
451};
452
453void omap_mcpdm_configure_dn_offsets(struct snd_soc_pcm_runtime *rtd,
454				    u8 rx1, u8 rx2)
455{
456	struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(rtd->cpu_dai);
457
458	mcpdm->dn_rx_offset = MCPDM_DNOFST_RX1(rx1) | MCPDM_DNOFST_RX2(rx2);
459}
460EXPORT_SYMBOL_GPL(omap_mcpdm_configure_dn_offsets);
461
462static int asoc_mcpdm_probe(struct platform_device *pdev)
463{
464	struct omap_mcpdm *mcpdm;
465	struct resource *res;
466	int ret;
467
468	mcpdm = devm_kzalloc(&pdev->dev, sizeof(struct omap_mcpdm), GFP_KERNEL);
469	if (!mcpdm)
470		return -ENOMEM;
471
472	platform_set_drvdata(pdev, mcpdm);
473
474	mutex_init(&mcpdm->mutex);
475
476	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dma");
477	if (res == NULL)
478		return -ENOMEM;
479
480	mcpdm->dma_data[0].addr = res->start + MCPDM_REG_DN_DATA;
481	mcpdm->dma_data[1].addr = res->start + MCPDM_REG_UP_DATA;
482
483	mcpdm->dma_data[0].filter_data = "dn_link";
484	mcpdm->dma_data[1].filter_data = "up_link";
485
486	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mpu");
487	mcpdm->io_base = devm_ioremap_resource(&pdev->dev, res);
488	if (IS_ERR(mcpdm->io_base))
489		return PTR_ERR(mcpdm->io_base);
490
491	mcpdm->irq = platform_get_irq(pdev, 0);
492	if (mcpdm->irq < 0)
493		return mcpdm->irq;
494
495	mcpdm->dev = &pdev->dev;
496
497	ret =  devm_snd_soc_register_component(&pdev->dev,
498					       &omap_mcpdm_component,
499					       &omap_mcpdm_dai, 1);
500	if (ret)
501		return ret;
502
503	return omap_pcm_platform_register(&pdev->dev);
504}
505
506static const struct of_device_id omap_mcpdm_of_match[] = {
507	{ .compatible = "ti,omap4-mcpdm", },
508	{ }
509};
510MODULE_DEVICE_TABLE(of, omap_mcpdm_of_match);
511
512static struct platform_driver asoc_mcpdm_driver = {
513	.driver = {
514		.name	= "omap-mcpdm",
515		.of_match_table = omap_mcpdm_of_match,
516	},
517
518	.probe	= asoc_mcpdm_probe,
519};
520
521module_platform_driver(asoc_mcpdm_driver);
522
523MODULE_ALIAS("platform:omap-mcpdm");
524MODULE_AUTHOR("Misael Lopez Cruz <misael.lopez@ti.com>");
525MODULE_DESCRIPTION("OMAP PDM SoC Interface");
526MODULE_LICENSE("GPL");
527