aboutsummaryrefslogtreecommitdiffstats
path: root/sound/arm/pxa2xx-ac97-lib.c
blob: d1aa4218f1299ebccb813d0b8ef6c6fb9d8c3479 (plain) (blame)
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
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
/*
 * Based on sound/arm/pxa2xx-ac97.c and sound/soc/pxa/pxa2xx-ac97.c
 * which contain:
 *
 * Author:	Nicolas Pitre
 * Created:	Dec 02, 2004
 * Copyright:	MontaVista Software Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/module.h>

#include <sound/ac97_codec.h>
#include <sound/pxa2xx-lib.h>

#include <asm/irq.h>
#include <mach/regs-ac97.h>
#include <mach/audio.h>

static DEFINE_MUTEX(car_mutex);
static DECLARE_WAIT_QUEUE_HEAD(gsr_wq);
static volatile long gsr_bits;
static struct clk *ac97_clk;
static struct clk *ac97conf_clk;
static int reset_gpio;

extern void pxa27x_assert_ac97reset(int reset_gpio, int on);

/*
 * Beware PXA27x bugs:
 *
 *   o Slot 12 read from modem space will hang controller.
 *   o CDONE, SDONE interrupt fails after any slot 12 IO.
 *
 * We therefore have an hybrid approach for waiting on SDONE (interrupt or
 * 1 jiffy timeout if interrupt never comes).
 */

unsigned short pxa2xx_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
{
	unsigned short val = -1;
	volatile u32 *reg_addr;

	mutex_lock(&car_mutex);

	/* set up primary or secondary codec space */
	if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
		reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
	else
		reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
	reg_addr += (reg >> 1);

	/* start read access across the ac97 link */
	GSR = GSR_CDONE | GSR_SDONE;
	gsr_bits = 0;
	val = *reg_addr;
	if (reg == AC97_GPIO_STATUS)
		goto out;
	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1) <= 0 &&
	    !((GSR | gsr_bits) & GSR_SDONE)) {
		printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n",
				__func__, reg, GSR | gsr_bits);
		val = -1;
		goto out;
	}

	/* valid data now */
	GSR = GSR_CDONE | GSR_SDONE;
	gsr_bits = 0;
	val = *reg_addr;
	/* but we've just started another cycle... */
	wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1);

out:	mutex_unlock(&car_mutex);
	return val;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_read);

void pxa2xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
			unsigned short val)
{
	volatile u32 *reg_addr;

	mutex_lock(&car_mutex);

	/* set up primary or secondary codec space */
	if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
		reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
	else
		reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
	reg_addr += (reg >> 1);

	GSR = GSR_CDONE | GSR_SDONE;
	gsr_bits = 0;
	*reg_addr = val;
	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_CDONE, 1) <= 0 &&
	    !((GSR | gsr_bits) & GSR_CDONE))
		printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n",
				__func__, reg, GSR | gsr_bits);

	mutex_unlock(&car_mutex);
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_write);

#ifdef CONFIG_PXA25x
static inline void pxa_ac97_warm_pxa25x(void)
{
	gsr_bits = 0;

	GCR |= GCR_WARM_RST | GCR_PRIRDY_IEN | GCR_SECRDY_IEN;
	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
}

static inline void pxa_ac97_cold_pxa25x(void)
{
	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */

	gsr_bits = 0;

	GCR = GCR_COLD_RST;
	GCR |= GCR_CDONE_IE|GCR_SDONE_IE;
	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
}
#endif

#ifdef CONFIG_PXA27x
static inline void pxa_ac97_warm_pxa27x(void)
{
	gsr_bits = 0;

	/* warm reset broken on Bulverde, so manually keep AC97 reset high */
	pxa27x_assert_ac97reset(reset_gpio, 1);
	udelay(10);
	GCR |= GCR_WARM_RST;
	pxa27x_assert_ac97reset(reset_gpio, 0);
	udelay(500);
}

static inline void pxa_ac97_cold_pxa27x(void)
{
	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */

	gsr_bits = 0;

	/* PXA27x Developers Manual section 13.5.2.2.1 */
	clk_enable(ac97conf_clk);
	udelay(5);
	clk_disable(ac97conf_clk);
	GCR = GCR_COLD_RST;
	udelay(50);
}
#endif

#ifdef CONFIG_PXA3xx
static inline void pxa_ac97_warm_pxa3xx(void)
{
	int timeout = 100;

	gsr_bits = 0;

	/* Can't use interrupts */
	GCR |= GCR_WARM_RST;
	while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
		mdelay(1);
}

static inline void pxa_ac97_cold_pxa3xx(void)
{
	int timeout = 1000;

	/* Hold CLKBPB for 100us */
	GCR = 0;
	GCR = GCR_CLKBPB;
	udelay(100);
	GCR = 0;

	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */

	gsr_bits = 0;

	/* Can't use interrupts on PXA3xx */
	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);

	GCR = GCR_WARM_RST | GCR_COLD_RST;
	while (!(GSR & (GSR_PCR | GSR_SCR)) && timeout--)
		mdelay(10);
}
#endif

bool pxa2xx_ac97_try_warm_reset(struct snd_ac97 *ac97)
{
	unsigned long gsr;

#ifdef CONFIG_PXA25x
	if (cpu_is_pxa25x())
		pxa_ac97_warm_pxa25x();
	else
#endif
#ifdef CONFIG_PXA27x
	if (cpu_is_pxa27x())
		pxa_ac97_warm_pxa27x();
	else
#endif
#ifdef CONFIG_PXA3xx
	if (cpu_is_pxa3xx())
		pxa_ac97_warm_pxa3xx();
	else
#endif
		BUG();
	gsr = GSR | gsr_bits;
	if (!(gsr & (GSR_PCR | GSR_SCR))) {
		printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
				 __func__, gsr);

		return false;
	}

	return true;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_warm_reset);

bool pxa2xx_ac97_try_cold_reset(struct snd_ac97 *ac97)
{
	unsigned long gsr;

#ifdef CONFIG_PXA25x
	if (cpu_is_pxa25x())
		pxa_ac97_cold_pxa25x();
	else
#endif
#ifdef CONFIG_PXA27x
	if (cpu_is_pxa27x())
		pxa_ac97_cold_pxa27x();
	else
#endif
#ifdef CONFIG_PXA3xx
	if (cpu_is_pxa3xx())
		pxa_ac97_cold_pxa3xx();
	else
#endif
		BUG();

	gsr = GSR | gsr_bits;
	if (!(gsr & (GSR_PCR | GSR_SCR))) {
		printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
				 __func__, gsr);

		return false;
	}

	return true;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_cold_reset);


void pxa2xx_ac97_finish_reset(struct snd_ac97 *ac97)
{
	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
	GCR |= GCR_SDONE_IE|GCR_CDONE_IE;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_finish_reset);

static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
{
	long status;

	status = GSR;
	if (status) {
		GSR = status;
		gsr_bits |= status;
		wake_up(&gsr_wq);

		/* Although we don't use those we still need to clear them
		   since they tend to spuriously trigger when MMC is used
		   (hardware bug? go figure)... */
		if (cpu_is_pxa27x()) {
			MISR = MISR_EOC;
			PISR = PISR_EOC;
			MCSR = MCSR_EOC;
		}

		return IRQ_HANDLED;
	}

	return IRQ_NONE;
}

#ifdef CONFIG_PM
int pxa2xx_ac97_hw_suspend(void)
{
	GCR |= GCR_ACLINK_OFF;
	clk_disable(ac97_clk);
	return 0;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_suspend);

int pxa2xx_ac97_hw_resume(void)
{
	clk_enable(ac97_clk);
	return 0;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
#endif

int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev)
{
	int ret;
	pxa2xx_audio_ops_t *pdata = dev->dev.platform_data;

	if (pdata) {
		switch (pdata->reset_gpio) {
		case 95:
		case 113:
			reset_gpio = pdata->reset_gpio;
			break;
		case 0:
			reset_gpio = 113;
			break;
		case -1:
			break;
		default:
			dev_err(&dev->dev, "Invalid reset GPIO %d\n",
				pdata->reset_gpio);
		}
	} else {
		if (cpu_is_pxa27x())
			reset_gpio = 113;
	}

	if (cpu_is_pxa27x()) {
		/* Use GPIO 113 as AC97 Reset on Bulverde */
		pxa27x_assert_ac97reset(reset_gpio, 0);
		ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
		if (IS_ERR(ac97conf_clk)) {
			ret = PTR_ERR(ac97conf_clk);
			ac97conf_clk = NULL;
			goto err_conf;
		}
	}

	ac97_clk = clk_get(&dev->dev, "AC97CLK");
	if (IS_ERR(ac97_clk)) {
		ret = PTR_ERR(ac97_clk);
		ac97_clk = NULL;
		goto err_clk;
	}

	ret = clk_enable(ac97_clk);
	if (ret)
		goto err_clk2;

	ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, 0, "AC97", NULL);
	if (ret < 0)
		goto err_irq;

	return 0;

err_irq:
	GCR |= GCR_ACLINK_OFF;
err_clk2:
	clk_put(ac97_clk);
	ac97_clk = NULL;
err_clk:
	if (ac97conf_clk) {
		clk_put(ac97conf_clk);
		ac97conf_clk = NULL;
	}
err_conf:
	return ret;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);

void pxa2xx_ac97_hw_remove(struct platform_device *dev)
{
	GCR |= GCR_ACLINK_OFF;
	free_irq(IRQ_AC97, NULL);
	if (ac97conf_clk) {
		clk_put(ac97conf_clk);
		ac97conf_clk = NULL;
	}
	clk_disable(ac97_clk);
	clk_put(ac97_clk);
	ac97_clk = NULL;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_remove);

MODULE_AUTHOR("Nicolas Pitre");
MODULE_DESCRIPTION("Intel/Marvell PXA sound library");
MODULE_LICENSE("GPL");