summaryrefslogtreecommitdiffstats
path: root/sound/drivers/pcsp/pcsp_lib.c
blob: 40f95f549d2bb5739a7e777e1b27c3acdda3a3f0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
/*
 * PC-Speaker driver for Linux
 *
 * Copyright (C) 1993-1997  Michael Beck
 * Copyright (C) 1997-2001  David Woodhouse
 * Copyright (C) 2001-2008  Stas Sergeev
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/interrupt.h>
#include <sound/pcm.h>
#include <asm/io.h>
#include "pcsp.h"

static int nforce_wa;
module_param(nforce_wa, bool, 0444);
MODULE_PARM_DESC(nforce_wa, "Apply NForce chipset workaround "
		"(expect bad sound)");

#define DMIX_WANTS_S16	1

/*
 * Call snd_pcm_period_elapsed in a tasklet
 * This avoids spinlock messes and long-running irq contexts
 */
static void pcsp_call_pcm_elapsed(unsigned long priv)
{
	if (atomic_read(&pcsp_chip.timer_active)) {
		struct snd_pcm_substream *substream;
		substream = pcsp_chip.playback_substream;
		if (substream)
			snd_pcm_period_elapsed(substream);
	}
}

static DECLARE_TASKLET(pcsp_pcm_tasklet, pcsp_call_pcm_elapsed, 0);

enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle)
{
	unsigned char timer_cnt, val;
	int fmt_size, periods_elapsed;
	u64 ns;
	size_t period_bytes, buffer_bytes;
	struct snd_pcm_substream *substream;
	struct snd_pcm_runtime *runtime;
	struct snd_pcsp *chip = container_of(handle, struct snd_pcsp, timer);
	unsigned long flags;

	if (chip->thalf) {
		outb(chip->val61, 0x61);
		chip->thalf = 0;
		if (!atomic_read(&chip->timer_active))
			goto stop;
		hrtimer_forward(&chip->timer, chip->timer.expires,
				ktime_set(0, chip->ns_rem));
		return HRTIMER_RESTART;
	}

	if (!atomic_read(&chip->timer_active))
		goto stop;
	substream = chip->playback_substream;
	if (!substream)
		goto stop;

	runtime = substream->runtime;
	fmt_size = snd_pcm_format_physical_width(runtime->format) >> 3;
	/* assume it is mono! */
	val = runtime->dma_area[chip->playback_ptr + fmt_size - 1];
	if (snd_pcm_format_signed(runtime->format))
		val ^= 0x80;
	timer_cnt = val * CUR_DIV() / 256;

	if (timer_cnt && chip->enable) {
		spin_lock(&i8253_lock);
		if (!nforce_wa) {
			outb_p(chip->val61, 0x61);
			outb_p(timer_cnt, 0x42);
			outb(chip->val61 ^ 1, 0x61);
		} else {
			outb(chip->val61 ^ 2, 0x61);
			chip->thalf = 1;
		}
		spin_unlock(&i8253_lock);
	}

	period_bytes = snd_pcm_lib_period_bytes(substream);
	buffer_bytes = snd_pcm_lib_buffer_bytes(substream);

	spin_lock_irqsave(&chip->substream_lock, flags);
	chip->playback_ptr += PCSP_INDEX_INC() * fmt_size;
	periods_elapsed = chip->playback_ptr - chip->period_ptr;
	if (periods_elapsed < 0) {
#if PCSP_DEBUG
		printk(KERN_INFO "PCSP: buffer_bytes mod period_bytes != 0 ? "
			"(%zi %zi %zi)\n",
			chip->playback_ptr, period_bytes, buffer_bytes);
#endif
		periods_elapsed += buffer_bytes;
	}
	periods_elapsed /= period_bytes;
	/* wrap the pointer _before_ calling snd_pcm_period_elapsed(),
	 * or ALSA will BUG on us. */
	chip->playback_ptr %= buffer_bytes;

	if (periods_elapsed) {
		chip->period_ptr += periods_elapsed * period_bytes;
		chip->period_ptr %= buffer_bytes;
		tasklet_schedule(&pcsp_pcm_tasklet);
	}
	spin_unlock_irqrestore(&chip->substream_lock, flags);

	if (!atomic_read(&chip->timer_active))
		goto stop;

	chip->ns_rem = PCSP_PERIOD_NS();
	ns = (chip->thalf ? PCSP_CALC_NS(timer_cnt) : chip->ns_rem);
	chip->ns_rem -= ns;
	hrtimer_forward(&chip->timer, chip->timer.expires, ktime_set(0, ns));
	return HRTIMER_RESTART;

 stop:
	return HRTIMER_NORESTART;
}

static void pcsp_start_playing(struct snd_pcsp *chip)
{
#if PCSP_DEBUG
	printk(KERN_INFO "PCSP: start_playing called\n");
#endif
	if (atomic_read(&chip->timer_active)) {
		printk(KERN_ERR "PCSP: Timer already active\n");
		return;
	}

	spin_lock(&i8253_lock);
	chip->val61 = inb(0x61) | 0x03;
	outb_p(0x92, 0x43);	/* binary, mode 1, LSB only, ch 2 */
	spin_unlock(&i8253_lock);
	atomic_set(&chip->timer_active, 1);
	chip->thalf = 0;

	hrtimer_start(&pcsp_chip.timer, ktime_set(0, 0), HRTIMER_MODE_REL);
}

static void pcsp_stop_playing(struct snd_pcsp *chip)
{
#if PCSP_DEBUG
	printk(KERN_INFO "PCSP: stop_playing called\n");
#endif
	if (!atomic_read(&chip->timer_active))
		return;

	atomic_set(&chip->timer_active, 0);
	spin_lock(&i8253_lock);
	/* restore the timer */
	outb_p(0xb6, 0x43);	/* binary, mode 3, LSB/MSB, ch 2 */
	outb(chip->val61 & 0xFC, 0x61);
	spin_unlock(&i8253_lock);
}

/*
 * Force to stop and sync the stream
 */
void pcsp_sync_stop(struct snd_pcsp *chip)
{
	local_irq_disable();
	pcsp_stop_playing(chip);
	local_irq_enable();
	hrtimer_cancel(&chip->timer);
	tasklet_kill(&pcsp_pcm_tasklet);
}

static int snd_pcsp_playback_close(struct snd_pcm_substream *substream)
{
	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
#if PCSP_DEBUG
	printk(KERN_INFO "PCSP: close called\n");
#endif
	pcsp_sync_stop(chip);
	chip->playback_substream = NULL;
	return 0;
}

static int snd_pcsp_playback_hw_params(struct snd_pcm_substream *substream,
				       struct snd_pcm_hw_params *hw_params)
{
	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
	int err;
	pcsp_sync_stop(chip);
	err = snd_pcm_lib_malloc_pages(substream,
				      params_buffer_bytes(hw_params));
	if (err < 0)
		return err;
	return 0;
}

static int snd_pcsp_playback_hw_free(struct snd_pcm_substream *substream)
{
	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
#if PCSP_DEBUG
	printk(KERN_INFO "PCSP: hw_free called\n");
#endif
	pcsp_sync_stop(chip);
	return snd_pcm_lib_free_pages(substream);
}

static int snd_pcsp_playback_prepare(struct snd_pcm_substream *substream)
{
	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
#if PCSP_DEBUG
	printk(KERN_INFO "PCSP: prepare called, "
			"size=%zi psize=%zi f=%zi f1=%i\n",
			snd_pcm_lib_buffer_bytes(substream),
			snd_pcm_lib_period_bytes(substream),
			snd_pcm_lib_buffer_bytes(substream) /
			snd_pcm_lib_period_bytes(substream),
			substream->runtime->periods);
#endif
	pcsp_sync_stop(chip);
	chip->playback_ptr = 0;
	chip->period_ptr = 0;
	return 0;
}

static int snd_pcsp_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
#if PCSP_DEBUG
	printk(KERN_INFO "PCSP: trigger called\n");
#endif
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
		pcsp_start_playing(chip);
		break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
		pcsp_stop_playing(chip);
		break;
	default:
		return -EINVAL;
	}
	return 0;
}

static snd_pcm_uframes_t snd_pcsp_playback_pointer(struct snd_pcm_substream
						   *substream)
{
	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
	unsigned int pos;
	spin_lock(&chip->substream_lock);
	pos = chip->playback_ptr;
	spin_unlock(&chip->substream_lock);
	return bytes_to_frames(substream->runtime, pos);
}

static struct snd_pcm_hardware snd_pcsp_playback = {
	.info = (SNDRV_PCM_INFO_INTERLEAVED |
		 SNDRV_PCM_INFO_HALF_DUPLEX |
		 SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID),
	.formats = (SNDRV_PCM_FMTBIT_U8
#if DMIX_WANTS_S16
		    | SNDRV_PCM_FMTBIT_S16_LE
#endif
	    ),
	.rates = SNDRV_PCM_RATE_KNOT,
	.rate_min = PCSP_DEFAULT_SRATE,
	.rate_max = PCSP_DEFAULT_SRATE,
	.channels_min = 1,
	.channels_max = 1,
	.buffer_bytes_max = PCSP_BUFFER_SIZE,
	.period_bytes_min = 64,
	.period_bytes_max = PCSP_MAX_PERIOD_SIZE,
	.periods_min = 2,
	.periods_max = PCSP_MAX_PERIODS,
	.fifo_size = 0,
};

static int snd_pcsp_playback_open(struct snd_pcm_substream *substream)
{
	struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
#if PCSP_DEBUG
	printk(KERN_INFO "PCSP: open called\n");
#endif
	if (atomic_read(&chip->timer_active)) {
		printk(KERN_ERR "PCSP: still active!!\n");
		return -EBUSY;
	}
	runtime->hw = snd_pcsp_playback;
	chip->playback_substream = substream;
	return 0;
}

static struct snd_pcm_ops snd_pcsp_playback_ops = {
	.open = snd_pcsp_playback_open,
	.close = snd_pcsp_playback_close,
	.ioctl = snd_pcm_lib_ioctl,
	.hw_params = snd_pcsp_playback_hw_params,
	.hw_free = snd_pcsp_playback_hw_free,
	.prepare = snd_pcsp_playback_prepare,
	.trigger = snd_pcsp_trigger,
	.pointer = snd_pcsp_playback_pointer,
};

int __devinit snd_pcsp_new_pcm(struct snd_pcsp *chip)
{
	int err;

	err = snd_pcm_new(chip->card, "pcspeaker", 0, 1, 0, &chip->pcm);
	if (err < 0)
		return err;

	snd_pcm_set_ops(chip->pcm, SNDRV_PCM_STREAM_PLAYBACK,
			&snd_pcsp_playback_ops);

	chip->pcm->private_data = chip;
	chip->pcm->info_flags = SNDRV_PCM_INFO_HALF_DUPLEX;
	strcpy(chip->pcm->name, "pcsp");

	snd_pcm_lib_preallocate_pages_for_all(chip->pcm,
					      SNDRV_DMA_TYPE_CONTINUOUS,
					      snd_dma_continuous_data
					      (GFP_KERNEL), PCSP_BUFFER_SIZE,
					      PCSP_BUFFER_SIZE);

	return 0;
}