1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * i2sbus driver -- pcm routines
4 *
5 * Copyright 2006 Johannes Berg <johannes@sipsolutions.net>
6 */
7
8#include <linux/io.h>
9#include <linux/delay.h>
10#include <linux/slab.h>
11#include <sound/core.h>
12#include <asm/macio.h>
13#include <linux/pci.h>
14#include <linux/module.h>
15#include "../soundbus.h"
16#include "i2sbus.h"
17
18static inline void get_pcm_info(struct i2sbus_dev *i2sdev, int in,
19				struct pcm_info **pi, struct pcm_info **other)
20{
21	if (in) {
22		if (pi)
23			*pi = &i2sdev->in;
24		if (other)
25			*other = &i2sdev->out;
26	} else {
27		if (pi)
28			*pi = &i2sdev->out;
29		if (other)
30			*other = &i2sdev->in;
31	}
32}
33
34static int clock_and_divisors(int mclk, int sclk, int rate, int *out)
35{
36	/* sclk must be derived from mclk! */
37	if (mclk % sclk)
38		return -1;
39	/* derive sclk register value */
40	if (i2s_sf_sclkdiv(mclk / sclk, out))
41		return -1;
42
43	if (I2S_CLOCK_SPEED_18MHz % (rate * mclk) == 0) {
44		if (!i2s_sf_mclkdiv(I2S_CLOCK_SPEED_18MHz / (rate * mclk), out)) {
45			*out |= I2S_SF_CLOCK_SOURCE_18MHz;
46			return 0;
47		}
48	}
49	if (I2S_CLOCK_SPEED_45MHz % (rate * mclk) == 0) {
50		if (!i2s_sf_mclkdiv(I2S_CLOCK_SPEED_45MHz / (rate * mclk), out)) {
51			*out |= I2S_SF_CLOCK_SOURCE_45MHz;
52			return 0;
53		}
54	}
55	if (I2S_CLOCK_SPEED_49MHz % (rate * mclk) == 0) {
56		if (!i2s_sf_mclkdiv(I2S_CLOCK_SPEED_49MHz / (rate * mclk), out)) {
57			*out |= I2S_SF_CLOCK_SOURCE_49MHz;
58			return 0;
59		}
60	}
61	return -1;
62}
63
64#define CHECK_RATE(rate)						\
65	do { if (rates & SNDRV_PCM_RATE_ ##rate) {			\
66		int dummy;						\
67		if (clock_and_divisors(sysclock_factor,			\
68				       bus_factor, rate, &dummy))	\
69			rates &= ~SNDRV_PCM_RATE_ ##rate;		\
70	} } while (0)
71
72static int i2sbus_pcm_open(struct i2sbus_dev *i2sdev, int in)
73{
74	struct pcm_info *pi, *other;
75	struct soundbus_dev *sdev;
76	int masks_inited = 0, err;
77	struct codec_info_item *cii, *rev;
78	struct snd_pcm_hardware *hw;
79	u64 formats = 0;
80	unsigned int rates = 0;
81	struct transfer_info v;
82	int result = 0;
83	int bus_factor = 0, sysclock_factor = 0;
84	int found_this;
85
86	mutex_lock(&i2sdev->lock);
87
88	get_pcm_info(i2sdev, in, &pi, &other);
89
90	hw = &pi->substream->runtime->hw;
91	sdev = &i2sdev->sound;
92
93	if (pi->active) {
94		/* alsa messed up */
95		result = -EBUSY;
96		goto out_unlock;
97	}
98
99	/* we now need to assign the hw */
100	list_for_each_entry(cii, &sdev->codec_list, list) {
101		struct transfer_info *ti = cii->codec->transfers;
102		bus_factor = cii->codec->bus_factor;
103		sysclock_factor = cii->codec->sysclock_factor;
104		while (ti->formats && ti->rates) {
105			v = *ti;
106			if (ti->transfer_in == in
107			    && cii->codec->usable(cii, ti, &v)) {
108				if (masks_inited) {
109					formats &= v.formats;
110					rates &= v.rates;
111				} else {
112					formats = v.formats;
113					rates = v.rates;
114					masks_inited = 1;
115				}
116			}
117			ti++;
118		}
119	}
120	if (!masks_inited || !bus_factor || !sysclock_factor) {
121		result = -ENODEV;
122		goto out_unlock;
123	}
124	/* bus dependent stuff */
125	hw->info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
126		   SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_RESUME |
127		   SNDRV_PCM_INFO_JOINT_DUPLEX;
128
129	CHECK_RATE(5512);
130	CHECK_RATE(8000);
131	CHECK_RATE(11025);
132	CHECK_RATE(16000);
133	CHECK_RATE(22050);
134	CHECK_RATE(32000);
135	CHECK_RATE(44100);
136	CHECK_RATE(48000);
137	CHECK_RATE(64000);
138	CHECK_RATE(88200);
139	CHECK_RATE(96000);
140	CHECK_RATE(176400);
141	CHECK_RATE(192000);
142	hw->rates = rates;
143
144	/* well. the codec might want 24 bits only, and we'll
145	 * ever only transfer 24 bits, but they are top-aligned!
146	 * So for alsa, we claim that we're doing full 32 bit
147	 * while in reality we'll ignore the lower 8 bits of
148	 * that when doing playback (they're transferred as 0
149	 * as far as I know, no codecs we have are 32-bit capable
150	 * so I can't really test) and when doing recording we'll
151	 * always have those lower 8 bits recorded as 0 */
152	if (formats & SNDRV_PCM_FMTBIT_S24_BE)
153		formats |= SNDRV_PCM_FMTBIT_S32_BE;
154	if (formats & SNDRV_PCM_FMTBIT_U24_BE)
155		formats |= SNDRV_PCM_FMTBIT_U32_BE;
156	/* now mask off what we can support. I suppose we could
157	 * also support S24_3LE and some similar formats, but I
158	 * doubt there's a codec that would be able to use that,
159	 * so we don't support it here. */
160	hw->formats = formats & (SNDRV_PCM_FMTBIT_S16_BE |
161				 SNDRV_PCM_FMTBIT_U16_BE |
162				 SNDRV_PCM_FMTBIT_S32_BE |
163				 SNDRV_PCM_FMTBIT_U32_BE);
164
165	/* we need to set the highest and lowest rate possible.
166	 * These are the highest and lowest rates alsa can
167	 * support properly in its bitfield.
168	 * Below, we'll use that to restrict to the rate
169	 * currently in use (if any). */
170	hw->rate_min = 5512;
171	hw->rate_max = 192000;
172	/* if the other stream is active, then we can only
173	 * support what it is currently using.
174	 * FIXME: I lied. This comment is wrong. We can support
175	 * anything that works with the same serial format, ie.
176	 * when recording 24 bit sound we can well play 16 bit
177	 * sound at the same time iff using the same transfer mode.
178	 */
179	if (other->active) {
180		/* FIXME: is this guaranteed by the alsa api? */
181		hw->formats &= pcm_format_to_bits(i2sdev->format);
182		/* see above, restrict rates to the one we already have */
183		hw->rate_min = i2sdev->rate;
184		hw->rate_max = i2sdev->rate;
185	}
186
187	hw->channels_min = 2;
188	hw->channels_max = 2;
189	/* these are somewhat arbitrary */
190	hw->buffer_bytes_max = 131072;
191	hw->period_bytes_min = 256;
192	hw->period_bytes_max = 16384;
193	hw->periods_min = 3;
194	hw->periods_max = MAX_DBDMA_COMMANDS;
195	err = snd_pcm_hw_constraint_integer(pi->substream->runtime,
196					    SNDRV_PCM_HW_PARAM_PERIODS);
197	if (err < 0) {
198		result = err;
199		goto out_unlock;
200	}
201	list_for_each_entry(cii, &sdev->codec_list, list) {
202		if (cii->codec->open) {
203			err = cii->codec->open(cii, pi->substream);
204			if (err) {
205				result = err;
206				/* unwind */
207				found_this = 0;
208				list_for_each_entry_reverse(rev,
209				    &sdev->codec_list, list) {
210					if (found_this && rev->codec->close) {
211						rev->codec->close(rev,
212								pi->substream);
213					}
214					if (rev == cii)
215						found_this = 1;
216				}
217				goto out_unlock;
218			}
219		}
220	}
221
222 out_unlock:
223	mutex_unlock(&i2sdev->lock);
224	return result;
225}
226
227#undef CHECK_RATE
228
229static int i2sbus_pcm_close(struct i2sbus_dev *i2sdev, int in)
230{
231	struct codec_info_item *cii;
232	struct pcm_info *pi;
233	int err = 0, tmp;
234
235	mutex_lock(&i2sdev->lock);
236
237	get_pcm_info(i2sdev, in, &pi, NULL);
238
239	list_for_each_entry(cii, &i2sdev->sound.codec_list, list) {
240		if (cii->codec->close) {
241			tmp = cii->codec->close(cii, pi->substream);
242			if (tmp)
243				err = tmp;
244		}
245	}
246
247	pi->substream = NULL;
248	pi->active = 0;
249	mutex_unlock(&i2sdev->lock);
250	return err;
251}
252
253static void i2sbus_wait_for_stop(struct i2sbus_dev *i2sdev,
254				 struct pcm_info *pi)
255{
256	unsigned long flags;
257	DECLARE_COMPLETION_ONSTACK(done);
258	long timeout;
259
260	spin_lock_irqsave(&i2sdev->low_lock, flags);
261	if (pi->dbdma_ring.stopping) {
262		pi->stop_completion = &done;
263		spin_unlock_irqrestore(&i2sdev->low_lock, flags);
264		timeout = wait_for_completion_timeout(&done, HZ);
265		spin_lock_irqsave(&i2sdev->low_lock, flags);
266		pi->stop_completion = NULL;
267		if (timeout == 0) {
268			/* timeout expired, stop dbdma forcefully */
269			printk(KERN_ERR "i2sbus_wait_for_stop: timed out\n");
270			/* make sure RUN, PAUSE and S0 bits are cleared */
271			out_le32(&pi->dbdma->control, (RUN | PAUSE | 1) << 16);
272			pi->dbdma_ring.stopping = 0;
273			timeout = 10;
274			while (in_le32(&pi->dbdma->status) & ACTIVE) {
275				if (--timeout <= 0)
276					break;
277				udelay(1);
278			}
279		}
280	}
281	spin_unlock_irqrestore(&i2sdev->low_lock, flags);
282}
283
284#ifdef CONFIG_PM
285void i2sbus_wait_for_stop_both(struct i2sbus_dev *i2sdev)
286{
287	struct pcm_info *pi;
288
289	get_pcm_info(i2sdev, 0, &pi, NULL);
290	i2sbus_wait_for_stop(i2sdev, pi);
291	get_pcm_info(i2sdev, 1, &pi, NULL);
292	i2sbus_wait_for_stop(i2sdev, pi);
293}
294#endif
295
296static inline int i2sbus_hw_free(struct snd_pcm_substream *substream, int in)
297{
298	struct i2sbus_dev *i2sdev = snd_pcm_substream_chip(substream);
299	struct pcm_info *pi;
300
301	get_pcm_info(i2sdev, in, &pi, NULL);
302	if (pi->dbdma_ring.stopping)
303		i2sbus_wait_for_stop(i2sdev, pi);
304	return 0;
305}
306
307static int i2sbus_playback_hw_free(struct snd_pcm_substream *substream)
308{
309	return i2sbus_hw_free(substream, 0);
310}
311
312static int i2sbus_record_hw_free(struct snd_pcm_substream *substream)
313{
314	return i2sbus_hw_free(substream, 1);
315}
316
317static int i2sbus_pcm_prepare(struct i2sbus_dev *i2sdev, int in)
318{
319	/* whee. Hard work now. The user has selected a bitrate
320	 * and bit format, so now we have to program our
321	 * I2S controller appropriately. */
322	struct snd_pcm_runtime *runtime;
323	struct dbdma_cmd *command;
324	int i, periodsize, nperiods;
325	dma_addr_t offset;
326	struct bus_info bi;
327	struct codec_info_item *cii;
328	int sfr = 0;		/* serial format register */
329	int dws = 0;		/* data word sizes reg */
330	int input_16bit;
331	struct pcm_info *pi, *other;
332	int cnt;
333	int result = 0;
334	unsigned int cmd, stopaddr;
335
336	mutex_lock(&i2sdev->lock);
337
338	get_pcm_info(i2sdev, in, &pi, &other);
339
340	if (pi->dbdma_ring.running) {
341		result = -EBUSY;
342		goto out_unlock;
343	}
344	if (pi->dbdma_ring.stopping)
345		i2sbus_wait_for_stop(i2sdev, pi);
346
347	if (!pi->substream || !pi->substream->runtime) {
348		result = -EINVAL;
349		goto out_unlock;
350	}
351
352	runtime = pi->substream->runtime;
353	pi->active = 1;
354	if (other->active &&
355	    ((i2sdev->format != runtime->format)
356	     || (i2sdev->rate != runtime->rate))) {
357		result = -EINVAL;
358		goto out_unlock;
359	}
360
361	i2sdev->format = runtime->format;
362	i2sdev->rate = runtime->rate;
363
364	periodsize = snd_pcm_lib_period_bytes(pi->substream);
365	nperiods = pi->substream->runtime->periods;
366	pi->current_period = 0;
367
368	/* generate dbdma command ring first */
369	command = pi->dbdma_ring.cmds;
370	memset(command, 0, (nperiods + 2) * sizeof(struct dbdma_cmd));
371
372	/* commands to DMA to/from the ring */
373	/*
374	 * For input, we need to do a graceful stop; if we abort
375	 * the DMA, we end up with leftover bytes that corrupt
376	 * the next recording.  To do this we set the S0 status
377	 * bit and wait for the DMA controller to stop.  Each
378	 * command has a branch condition to
379	 * make it branch to a stop command if S0 is set.
380	 * On input we also need to wait for the S7 bit to be
381	 * set before turning off the DMA controller.
382	 * In fact we do the graceful stop for output as well.
383	 */
384	offset = runtime->dma_addr;
385	cmd = (in? INPUT_MORE: OUTPUT_MORE) | BR_IFSET | INTR_ALWAYS;
386	stopaddr = pi->dbdma_ring.bus_cmd_start +
387		(nperiods + 1) * sizeof(struct dbdma_cmd);
388	for (i = 0; i < nperiods; i++, command++, offset += periodsize) {
389		command->command = cpu_to_le16(cmd);
390		command->cmd_dep = cpu_to_le32(stopaddr);
391		command->phy_addr = cpu_to_le32(offset);
392		command->req_count = cpu_to_le16(periodsize);
393	}
394
395	/* branch back to beginning of ring */
396	command->command = cpu_to_le16(DBDMA_NOP | BR_ALWAYS);
397	command->cmd_dep = cpu_to_le32(pi->dbdma_ring.bus_cmd_start);
398	command++;
399
400	/* set stop command */
401	command->command = cpu_to_le16(DBDMA_STOP);
402
403	/* ok, let's set the serial format and stuff */
404	switch (runtime->format) {
405	/* 16 bit formats */
406	case SNDRV_PCM_FORMAT_S16_BE:
407	case SNDRV_PCM_FORMAT_U16_BE:
408		/* FIXME: if we add different bus factors we need to
409		 * do more here!! */
410		bi.bus_factor = 0;
411		list_for_each_entry(cii, &i2sdev->sound.codec_list, list) {
412			bi.bus_factor = cii->codec->bus_factor;
413			break;
414		}
415		if (!bi.bus_factor) {
416			result = -ENODEV;
417			goto out_unlock;
418		}
419		input_16bit = 1;
420		break;
421	case SNDRV_PCM_FORMAT_S32_BE:
422	case SNDRV_PCM_FORMAT_U32_BE:
423		/* force 64x bus speed, otherwise the data cannot be
424		 * transferred quickly enough! */
425		bi.bus_factor = 64;
426		input_16bit = 0;
427		break;
428	default:
429		result = -EINVAL;
430		goto out_unlock;
431	}
432	/* we assume all sysclocks are the same! */
433	list_for_each_entry(cii, &i2sdev->sound.codec_list, list) {
434		bi.sysclock_factor = cii->codec->sysclock_factor;
435		break;
436	}
437
438	if (clock_and_divisors(bi.sysclock_factor,
439			       bi.bus_factor,
440			       runtime->rate,
441			       &sfr) < 0) {
442		result = -EINVAL;
443		goto out_unlock;
444	}
445	switch (bi.bus_factor) {
446	case 32:
447		sfr |= I2S_SF_SERIAL_FORMAT_I2S_32X;
448		break;
449	case 64:
450		sfr |= I2S_SF_SERIAL_FORMAT_I2S_64X;
451		break;
452	}
453	/* FIXME: THIS ASSUMES MASTER ALL THE TIME */
454	sfr |= I2S_SF_SCLK_MASTER;
455
456	list_for_each_entry(cii, &i2sdev->sound.codec_list, list) {
457		int err = 0;
458		if (cii->codec->prepare)
459			err = cii->codec->prepare(cii, &bi, pi->substream);
460		if (err) {
461			result = err;
462			goto out_unlock;
463		}
464	}
465	/* codecs are fine with it, so set our clocks */
466	if (input_16bit)
467		dws =	(2 << I2S_DWS_NUM_CHANNELS_IN_SHIFT) |
468			(2 << I2S_DWS_NUM_CHANNELS_OUT_SHIFT) |
469			I2S_DWS_DATA_IN_16BIT | I2S_DWS_DATA_OUT_16BIT;
470	else
471		dws =	(2 << I2S_DWS_NUM_CHANNELS_IN_SHIFT) |
472			(2 << I2S_DWS_NUM_CHANNELS_OUT_SHIFT) |
473			I2S_DWS_DATA_IN_24BIT | I2S_DWS_DATA_OUT_24BIT;
474
475	/* early exit if already programmed correctly */
476	/* not locking these is fine since we touch them only in this function */
477	if (in_le32(&i2sdev->intfregs->serial_format) == sfr
478	 && in_le32(&i2sdev->intfregs->data_word_sizes) == dws)
479		goto out_unlock;
480
481	/* let's notify the codecs about clocks going away.
482	 * For now we only do mastering on the i2s cell... */
483	list_for_each_entry(cii, &i2sdev->sound.codec_list, list)
484		if (cii->codec->switch_clock)
485			cii->codec->switch_clock(cii, CLOCK_SWITCH_PREPARE_SLAVE);
486
487	i2sbus_control_enable(i2sdev->control, i2sdev);
488	i2sbus_control_cell(i2sdev->control, i2sdev, 1);
489
490	out_le32(&i2sdev->intfregs->intr_ctl, I2S_PENDING_CLOCKS_STOPPED);
491
492	i2sbus_control_clock(i2sdev->control, i2sdev, 0);
493
494	msleep(1);
495
496	/* wait for clock stopped. This can apparently take a while... */
497	cnt = 100;
498	while (cnt-- &&
499	    !(in_le32(&i2sdev->intfregs->intr_ctl) & I2S_PENDING_CLOCKS_STOPPED)) {
500		msleep(5);
501	}
502	out_le32(&i2sdev->intfregs->intr_ctl, I2S_PENDING_CLOCKS_STOPPED);
503
504	/* not locking these is fine since we touch them only in this function */
505	out_le32(&i2sdev->intfregs->serial_format, sfr);
506	out_le32(&i2sdev->intfregs->data_word_sizes, dws);
507
508        i2sbus_control_enable(i2sdev->control, i2sdev);
509        i2sbus_control_cell(i2sdev->control, i2sdev, 1);
510        i2sbus_control_clock(i2sdev->control, i2sdev, 1);
511	msleep(1);
512
513	list_for_each_entry(cii, &i2sdev->sound.codec_list, list)
514		if (cii->codec->switch_clock)
515			cii->codec->switch_clock(cii, CLOCK_SWITCH_SLAVE);
516
517 out_unlock:
518	mutex_unlock(&i2sdev->lock);
519	return result;
520}
521
522#ifdef CONFIG_PM
523void i2sbus_pcm_prepare_both(struct i2sbus_dev *i2sdev)
524{
525	i2sbus_pcm_prepare(i2sdev, 0);
526	i2sbus_pcm_prepare(i2sdev, 1);
527}
528#endif
529
530static int i2sbus_pcm_trigger(struct i2sbus_dev *i2sdev, int in, int cmd)
531{
532	struct codec_info_item *cii;
533	struct pcm_info *pi;
534	int result = 0;
535	unsigned long flags;
536
537	spin_lock_irqsave(&i2sdev->low_lock, flags);
538
539	get_pcm_info(i2sdev, in, &pi, NULL);
540
541	switch (cmd) {
542	case SNDRV_PCM_TRIGGER_START:
543	case SNDRV_PCM_TRIGGER_RESUME:
544		if (pi->dbdma_ring.running) {
545			result = -EALREADY;
546			goto out_unlock;
547		}
548		list_for_each_entry(cii, &i2sdev->sound.codec_list, list)
549			if (cii->codec->start)
550				cii->codec->start(cii, pi->substream);
551		pi->dbdma_ring.running = 1;
552
553		if (pi->dbdma_ring.stopping) {
554			/* Clear the S0 bit, then see if we stopped yet */
555			out_le32(&pi->dbdma->control, 1 << 16);
556			if (in_le32(&pi->dbdma->status) & ACTIVE) {
557				/* possible race here? */
558				udelay(10);
559				if (in_le32(&pi->dbdma->status) & ACTIVE) {
560					pi->dbdma_ring.stopping = 0;
561					goto out_unlock; /* keep running */
562				}
563			}
564		}
565
566		/* make sure RUN, PAUSE and S0 bits are cleared */
567		out_le32(&pi->dbdma->control, (RUN | PAUSE | 1) << 16);
568
569		/* set branch condition select register */
570		out_le32(&pi->dbdma->br_sel, (1 << 16) | 1);
571
572		/* write dma command buffer address to the dbdma chip */
573		out_le32(&pi->dbdma->cmdptr, pi->dbdma_ring.bus_cmd_start);
574
575		/* initialize the frame count and current period */
576		pi->current_period = 0;
577		pi->frame_count = in_le32(&i2sdev->intfregs->frame_count);
578
579		/* set the DMA controller running */
580		out_le32(&pi->dbdma->control, (RUN << 16) | RUN);
581
582		/* off you go! */
583		break;
584
585	case SNDRV_PCM_TRIGGER_STOP:
586	case SNDRV_PCM_TRIGGER_SUSPEND:
587		if (!pi->dbdma_ring.running) {
588			result = -EALREADY;
589			goto out_unlock;
590		}
591		pi->dbdma_ring.running = 0;
592
593		/* Set the S0 bit to make the DMA branch to the stop cmd */
594		out_le32(&pi->dbdma->control, (1 << 16) | 1);
595		pi->dbdma_ring.stopping = 1;
596
597		list_for_each_entry(cii, &i2sdev->sound.codec_list, list)
598			if (cii->codec->stop)
599				cii->codec->stop(cii, pi->substream);
600		break;
601	default:
602		result = -EINVAL;
603		goto out_unlock;
604	}
605
606 out_unlock:
607	spin_unlock_irqrestore(&i2sdev->low_lock, flags);
608	return result;
609}
610
611static snd_pcm_uframes_t i2sbus_pcm_pointer(struct i2sbus_dev *i2sdev, int in)
612{
613	struct pcm_info *pi;
614	u32 fc;
615
616	get_pcm_info(i2sdev, in, &pi, NULL);
617
618	fc = in_le32(&i2sdev->intfregs->frame_count);
619	fc = fc - pi->frame_count;
620
621	if (fc >= pi->substream->runtime->buffer_size)
622		fc %= pi->substream->runtime->buffer_size;
623	return fc;
624}
625
626static inline void handle_interrupt(struct i2sbus_dev *i2sdev, int in)
627{
628	struct pcm_info *pi;
629	u32 fc, nframes;
630	u32 status;
631	int timeout, i;
632	int dma_stopped = 0;
633	struct snd_pcm_runtime *runtime;
634
635	spin_lock(&i2sdev->low_lock);
636	get_pcm_info(i2sdev, in, &pi, NULL);
637	if (!pi->dbdma_ring.running && !pi->dbdma_ring.stopping)
638		goto out_unlock;
639
640	i = pi->current_period;
641	runtime = pi->substream->runtime;
642	while (pi->dbdma_ring.cmds[i].xfer_status) {
643		if (le16_to_cpu(pi->dbdma_ring.cmds[i].xfer_status) & BT)
644			/*
645			 * BT is the branch taken bit.  If it took a branch
646			 * it is because we set the S0 bit to make it
647			 * branch to the stop command.
648			 */
649			dma_stopped = 1;
650		pi->dbdma_ring.cmds[i].xfer_status = 0;
651
652		if (++i >= runtime->periods) {
653			i = 0;
654			pi->frame_count += runtime->buffer_size;
655		}
656		pi->current_period = i;
657
658		/*
659		 * Check the frame count.  The DMA tends to get a bit
660		 * ahead of the frame counter, which confuses the core.
661		 */
662		fc = in_le32(&i2sdev->intfregs->frame_count);
663		nframes = i * runtime->period_size;
664		if (fc < pi->frame_count + nframes)
665			pi->frame_count = fc - nframes;
666	}
667
668	if (dma_stopped) {
669		timeout = 1000;
670		for (;;) {
671			status = in_le32(&pi->dbdma->status);
672			if (!(status & ACTIVE) && (!in || (status & 0x80)))
673				break;
674			if (--timeout <= 0) {
675				printk(KERN_ERR "i2sbus: timed out "
676				       "waiting for DMA to stop!\n");
677				break;
678			}
679			udelay(1);
680		}
681
682		/* Turn off DMA controller, clear S0 bit */
683		out_le32(&pi->dbdma->control, (RUN | PAUSE | 1) << 16);
684
685		pi->dbdma_ring.stopping = 0;
686		if (pi->stop_completion)
687			complete(pi->stop_completion);
688	}
689
690	if (!pi->dbdma_ring.running)
691		goto out_unlock;
692	spin_unlock(&i2sdev->low_lock);
693	/* may call _trigger again, hence needs to be unlocked */
694	snd_pcm_period_elapsed(pi->substream);
695	return;
696
697 out_unlock:
698	spin_unlock(&i2sdev->low_lock);
699}
700
701irqreturn_t i2sbus_tx_intr(int irq, void *devid)
702{
703	handle_interrupt((struct i2sbus_dev *)devid, 0);
704	return IRQ_HANDLED;
705}
706
707irqreturn_t i2sbus_rx_intr(int irq, void *devid)
708{
709	handle_interrupt((struct i2sbus_dev *)devid, 1);
710	return IRQ_HANDLED;
711}
712
713static int i2sbus_playback_open(struct snd_pcm_substream *substream)
714{
715	struct i2sbus_dev *i2sdev = snd_pcm_substream_chip(substream);
716
717	if (!i2sdev)
718		return -EINVAL;
719	i2sdev->out.substream = substream;
720	return i2sbus_pcm_open(i2sdev, 0);
721}
722
723static int i2sbus_playback_close(struct snd_pcm_substream *substream)
724{
725	struct i2sbus_dev *i2sdev = snd_pcm_substream_chip(substream);
726	int err;
727
728	if (!i2sdev)
729		return -EINVAL;
730	if (i2sdev->out.substream != substream)
731		return -EINVAL;
732	err = i2sbus_pcm_close(i2sdev, 0);
733	if (!err)
734		i2sdev->out.substream = NULL;
735	return err;
736}
737
738static int i2sbus_playback_prepare(struct snd_pcm_substream *substream)
739{
740	struct i2sbus_dev *i2sdev = snd_pcm_substream_chip(substream);
741
742	if (!i2sdev)
743		return -EINVAL;
744	if (i2sdev->out.substream != substream)
745		return -EINVAL;
746	return i2sbus_pcm_prepare(i2sdev, 0);
747}
748
749static int i2sbus_playback_trigger(struct snd_pcm_substream *substream, int cmd)
750{
751	struct i2sbus_dev *i2sdev = snd_pcm_substream_chip(substream);
752
753	if (!i2sdev)
754		return -EINVAL;
755	if (i2sdev->out.substream != substream)
756		return -EINVAL;
757	return i2sbus_pcm_trigger(i2sdev, 0, cmd);
758}
759
760static snd_pcm_uframes_t i2sbus_playback_pointer(struct snd_pcm_substream
761						 *substream)
762{
763	struct i2sbus_dev *i2sdev = snd_pcm_substream_chip(substream);
764
765	if (!i2sdev)
766		return -EINVAL;
767	if (i2sdev->out.substream != substream)
768		return 0;
769	return i2sbus_pcm_pointer(i2sdev, 0);
770}
771
772static const struct snd_pcm_ops i2sbus_playback_ops = {
773	.open =		i2sbus_playback_open,
774	.close =	i2sbus_playback_close,
775	.hw_free =	i2sbus_playback_hw_free,
776	.prepare =	i2sbus_playback_prepare,
777	.trigger =	i2sbus_playback_trigger,
778	.pointer =	i2sbus_playback_pointer,
779};
780
781static int i2sbus_record_open(struct snd_pcm_substream *substream)
782{
783	struct i2sbus_dev *i2sdev = snd_pcm_substream_chip(substream);
784
785	if (!i2sdev)
786		return -EINVAL;
787	i2sdev->in.substream = substream;
788	return i2sbus_pcm_open(i2sdev, 1);
789}
790
791static int i2sbus_record_close(struct snd_pcm_substream *substream)
792{
793	struct i2sbus_dev *i2sdev = snd_pcm_substream_chip(substream);
794	int err;
795
796	if (!i2sdev)
797		return -EINVAL;
798	if (i2sdev->in.substream != substream)
799		return -EINVAL;
800	err = i2sbus_pcm_close(i2sdev, 1);
801	if (!err)
802		i2sdev->in.substream = NULL;
803	return err;
804}
805
806static int i2sbus_record_prepare(struct snd_pcm_substream *substream)
807{
808	struct i2sbus_dev *i2sdev = snd_pcm_substream_chip(substream);
809
810	if (!i2sdev)
811		return -EINVAL;
812	if (i2sdev->in.substream != substream)
813		return -EINVAL;
814	return i2sbus_pcm_prepare(i2sdev, 1);
815}
816
817static int i2sbus_record_trigger(struct snd_pcm_substream *substream, int cmd)
818{
819	struct i2sbus_dev *i2sdev = snd_pcm_substream_chip(substream);
820
821	if (!i2sdev)
822		return -EINVAL;
823	if (i2sdev->in.substream != substream)
824		return -EINVAL;
825	return i2sbus_pcm_trigger(i2sdev, 1, cmd);
826}
827
828static snd_pcm_uframes_t i2sbus_record_pointer(struct snd_pcm_substream
829					       *substream)
830{
831	struct i2sbus_dev *i2sdev = snd_pcm_substream_chip(substream);
832
833	if (!i2sdev)
834		return -EINVAL;
835	if (i2sdev->in.substream != substream)
836		return 0;
837	return i2sbus_pcm_pointer(i2sdev, 1);
838}
839
840static const struct snd_pcm_ops i2sbus_record_ops = {
841	.open =		i2sbus_record_open,
842	.close =	i2sbus_record_close,
843	.hw_free =	i2sbus_record_hw_free,
844	.prepare =	i2sbus_record_prepare,
845	.trigger =	i2sbus_record_trigger,
846	.pointer =	i2sbus_record_pointer,
847};
848
849static void i2sbus_private_free(struct snd_pcm *pcm)
850{
851	struct i2sbus_dev *i2sdev = snd_pcm_chip(pcm);
852	struct codec_info_item *p, *tmp;
853
854	i2sdev->sound.pcm = NULL;
855	i2sdev->out.created = 0;
856	i2sdev->in.created = 0;
857	list_for_each_entry_safe(p, tmp, &i2sdev->sound.codec_list, list) {
858		printk(KERN_ERR "i2sbus: a codec didn't unregister!\n");
859		list_del(&p->list);
860		module_put(p->codec->owner);
861		kfree(p);
862	}
863	soundbus_dev_put(&i2sdev->sound);
864	module_put(THIS_MODULE);
865}
866
867int
868i2sbus_attach_codec(struct soundbus_dev *dev, struct snd_card *card,
869		    struct codec_info *ci, void *data)
870{
871	int err, in = 0, out = 0;
872	struct transfer_info *tmp;
873	struct i2sbus_dev *i2sdev = soundbus_dev_to_i2sbus_dev(dev);
874	struct codec_info_item *cii;
875
876	if (!dev->pcmname || dev->pcmid == -1) {
877		printk(KERN_ERR "i2sbus: pcm name and id must be set!\n");
878		return -EINVAL;
879	}
880
881	list_for_each_entry(cii, &dev->codec_list, list) {
882		if (cii->codec_data == data)
883			return -EALREADY;
884	}
885
886	if (!ci->transfers || !ci->transfers->formats
887	    || !ci->transfers->rates || !ci->usable)
888		return -EINVAL;
889
890	/* we currently code the i2s transfer on the clock, and support only
891	 * 32 and 64 */
892	if (ci->bus_factor != 32 && ci->bus_factor != 64)
893		return -EINVAL;
894
895	/* If you want to fix this, you need to keep track of what transport infos
896	 * are to be used, which codecs they belong to, and then fix all the
897	 * sysclock/busclock stuff above to depend on which is usable */
898	list_for_each_entry(cii, &dev->codec_list, list) {
899		if (cii->codec->sysclock_factor != ci->sysclock_factor) {
900			printk(KERN_DEBUG
901			       "cannot yet handle multiple different sysclocks!\n");
902			return -EINVAL;
903		}
904		if (cii->codec->bus_factor != ci->bus_factor) {
905			printk(KERN_DEBUG
906			       "cannot yet handle multiple different bus clocks!\n");
907			return -EINVAL;
908		}
909	}
910
911	tmp = ci->transfers;
912	while (tmp->formats && tmp->rates) {
913		if (tmp->transfer_in)
914			in = 1;
915		else
916			out = 1;
917		tmp++;
918	}
919
920	cii = kzalloc(sizeof(struct codec_info_item), GFP_KERNEL);
921	if (!cii)
922		return -ENOMEM;
923
924	/* use the private data to point to the codec info */
925	cii->sdev = soundbus_dev_get(dev);
926	cii->codec = ci;
927	cii->codec_data = data;
928
929	if (!cii->sdev) {
930		printk(KERN_DEBUG
931		       "i2sbus: failed to get soundbus dev reference\n");
932		err = -ENODEV;
933		goto out_free_cii;
934	}
935
936	if (!try_module_get(THIS_MODULE)) {
937		printk(KERN_DEBUG "i2sbus: failed to get module reference!\n");
938		err = -EBUSY;
939		goto out_put_sdev;
940	}
941
942	if (!try_module_get(ci->owner)) {
943		printk(KERN_DEBUG
944		       "i2sbus: failed to get module reference to codec owner!\n");
945		err = -EBUSY;
946		goto out_put_this_module;
947	}
948
949	if (!dev->pcm) {
950		err = snd_pcm_new(card, dev->pcmname, dev->pcmid, 0, 0,
951				  &dev->pcm);
952		if (err) {
953			printk(KERN_DEBUG "i2sbus: failed to create pcm\n");
954			goto out_put_ci_module;
955		}
956	}
957
958	/* ALSA yet again sucks.
959	 * If it is ever fixed, remove this line. See below. */
960	out = in = 1;
961
962	if (!i2sdev->out.created && out) {
963		if (dev->pcm->card != card) {
964			/* eh? */
965			printk(KERN_ERR
966			       "Can't attach same bus to different cards!\n");
967			err = -EINVAL;
968			goto out_put_ci_module;
969		}
970		err = snd_pcm_new_stream(dev->pcm, SNDRV_PCM_STREAM_PLAYBACK, 1);
971		if (err)
972			goto out_put_ci_module;
973		snd_pcm_set_ops(dev->pcm, SNDRV_PCM_STREAM_PLAYBACK,
974				&i2sbus_playback_ops);
975		dev->pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].dev->parent =
976			&dev->ofdev.dev;
977		i2sdev->out.created = 1;
978	}
979
980	if (!i2sdev->in.created && in) {
981		if (dev->pcm->card != card) {
982			printk(KERN_ERR
983			       "Can't attach same bus to different cards!\n");
984			err = -EINVAL;
985			goto out_put_ci_module;
986		}
987		err = snd_pcm_new_stream(dev->pcm, SNDRV_PCM_STREAM_CAPTURE, 1);
988		if (err)
989			goto out_put_ci_module;
990		snd_pcm_set_ops(dev->pcm, SNDRV_PCM_STREAM_CAPTURE,
991				&i2sbus_record_ops);
992		dev->pcm->streams[SNDRV_PCM_STREAM_CAPTURE].dev->parent =
993			&dev->ofdev.dev;
994		i2sdev->in.created = 1;
995	}
996
997	/* so we have to register the pcm after adding any substream
998	 * to it because alsa doesn't create the devices for the
999	 * substreams when we add them later.
1000	 * Therefore, force in and out on both busses (above) and
1001	 * register the pcm now instead of just after creating it.
1002	 */
1003	err = snd_device_register(card, dev->pcm);
1004	if (err) {
1005		printk(KERN_ERR "i2sbus: error registering new pcm\n");
1006		goto out_put_ci_module;
1007	}
1008	/* no errors any more, so let's add this to our list */
1009	list_add(&cii->list, &dev->codec_list);
1010
1011	dev->pcm->private_data = i2sdev;
1012	dev->pcm->private_free = i2sbus_private_free;
1013
1014	/* well, we really should support scatter/gather DMA */
1015	snd_pcm_set_managed_buffer_all(
1016		dev->pcm, SNDRV_DMA_TYPE_DEV,
1017		&macio_get_pci_dev(i2sdev->macio)->dev,
1018		64 * 1024, 64 * 1024);
1019
1020	return 0;
1021 out_put_ci_module:
1022	module_put(ci->owner);
1023 out_put_this_module:
1024	module_put(THIS_MODULE);
1025 out_put_sdev:
1026	soundbus_dev_put(dev);
1027 out_free_cii:
1028	kfree(cii);
1029	return err;
1030}
1031
1032void i2sbus_detach_codec(struct soundbus_dev *dev, void *data)
1033{
1034	struct codec_info_item *cii = NULL, *i;
1035
1036	list_for_each_entry(i, &dev->codec_list, list) {
1037		if (i->codec_data == data) {
1038			cii = i;
1039			break;
1040		}
1041	}
1042	if (cii) {
1043		list_del(&cii->list);
1044		module_put(cii->codec->owner);
1045		kfree(cii);
1046	}
1047	/* no more codecs, but still a pcm? */
1048	if (list_empty(&dev->codec_list) && dev->pcm) {
1049		/* the actual cleanup is done by the callback above! */
1050		snd_device_free(dev->pcm->card, dev->pcm);
1051	}
1052}
1053