xref: /openbmc/linux/sound/arm/pxa2xx-ac97-lib.c (revision 78c99ba1)
1 /*
2  * Based on sound/arm/pxa2xx-ac97.c and sound/soc/pxa/pxa2xx-ac97.c
3  * which contain:
4  *
5  * Author:	Nicolas Pitre
6  * Created:	Dec 02, 2004
7  * Copyright:	MontaVista Software Inc.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/platform_device.h>
16 #include <linux/interrupt.h>
17 #include <linux/clk.h>
18 #include <linux/delay.h>
19 
20 #include <sound/ac97_codec.h>
21 #include <sound/pxa2xx-lib.h>
22 
23 #include <asm/irq.h>
24 #include <mach/regs-ac97.h>
25 #include <mach/pxa2xx-gpio.h>
26 #include <mach/audio.h>
27 
28 static DEFINE_MUTEX(car_mutex);
29 static DECLARE_WAIT_QUEUE_HEAD(gsr_wq);
30 static volatile long gsr_bits;
31 static struct clk *ac97_clk;
32 static struct clk *ac97conf_clk;
33 static int reset_gpio;
34 
35 /*
36  * Beware PXA27x bugs:
37  *
38  *   o Slot 12 read from modem space will hang controller.
39  *   o CDONE, SDONE interrupt fails after any slot 12 IO.
40  *
41  * We therefore have an hybrid approach for waiting on SDONE (interrupt or
42  * 1 jiffy timeout if interrupt never comes).
43  */
44 
45 enum {
46 	RESETGPIO_FORCE_HIGH,
47 	RESETGPIO_FORCE_LOW,
48 	RESETGPIO_NORMAL_ALTFUNC
49 };
50 
51 /**
52  * set_resetgpio_mode - computes and sets the AC97_RESET gpio mode on PXA
53  * @mode: chosen action
54  *
55  * As the PXA27x CPUs suffer from a AC97 bug, a manual control of the reset line
56  * must be done to insure proper work of AC97 reset line.  This function
57  * computes the correct gpio_mode for further use by reset functions, and
58  * applied the change through pxa_gpio_mode.
59  */
60 static void set_resetgpio_mode(int resetgpio_action)
61 {
62 	int mode = 0;
63 
64 	if (reset_gpio)
65 		switch (resetgpio_action) {
66 		case RESETGPIO_NORMAL_ALTFUNC:
67 			if (reset_gpio == 113)
68 				mode = 113 | GPIO_ALT_FN_2_OUT;
69 			if (reset_gpio == 95)
70 				mode = 95 | GPIO_ALT_FN_1_OUT;
71 			break;
72 		case RESETGPIO_FORCE_LOW:
73 			mode = reset_gpio | GPIO_OUT | GPIO_DFLT_LOW;
74 			break;
75 		case RESETGPIO_FORCE_HIGH:
76 			mode = reset_gpio | GPIO_OUT | GPIO_DFLT_HIGH;
77 			break;
78 		};
79 
80 	if (mode)
81 		pxa_gpio_mode(mode);
82 }
83 
84 unsigned short pxa2xx_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
85 {
86 	unsigned short val = -1;
87 	volatile u32 *reg_addr;
88 
89 	mutex_lock(&car_mutex);
90 
91 	/* set up primary or secondary codec space */
92 	if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
93 		reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
94 	else
95 		reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
96 	reg_addr += (reg >> 1);
97 
98 	/* start read access across the ac97 link */
99 	GSR = GSR_CDONE | GSR_SDONE;
100 	gsr_bits = 0;
101 	val = *reg_addr;
102 	if (reg == AC97_GPIO_STATUS)
103 		goto out;
104 	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1) <= 0 &&
105 	    !((GSR | gsr_bits) & GSR_SDONE)) {
106 		printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n",
107 				__func__, reg, GSR | gsr_bits);
108 		val = -1;
109 		goto out;
110 	}
111 
112 	/* valid data now */
113 	GSR = GSR_CDONE | GSR_SDONE;
114 	gsr_bits = 0;
115 	val = *reg_addr;
116 	/* but we've just started another cycle... */
117 	wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1);
118 
119 out:	mutex_unlock(&car_mutex);
120 	return val;
121 }
122 EXPORT_SYMBOL_GPL(pxa2xx_ac97_read);
123 
124 void pxa2xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
125 			unsigned short val)
126 {
127 	volatile u32 *reg_addr;
128 
129 	mutex_lock(&car_mutex);
130 
131 	/* set up primary or secondary codec space */
132 	if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
133 		reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
134 	else
135 		reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
136 	reg_addr += (reg >> 1);
137 
138 	GSR = GSR_CDONE | GSR_SDONE;
139 	gsr_bits = 0;
140 	*reg_addr = val;
141 	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_CDONE, 1) <= 0 &&
142 	    !((GSR | gsr_bits) & GSR_CDONE))
143 		printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n",
144 				__func__, reg, GSR | gsr_bits);
145 
146 	mutex_unlock(&car_mutex);
147 }
148 EXPORT_SYMBOL_GPL(pxa2xx_ac97_write);
149 
150 #ifdef CONFIG_PXA25x
151 static inline void pxa_ac97_warm_pxa25x(void)
152 {
153 	gsr_bits = 0;
154 
155 	GCR |= GCR_WARM_RST | GCR_PRIRDY_IEN | GCR_SECRDY_IEN;
156 	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
157 }
158 
159 static inline void pxa_ac97_cold_pxa25x(void)
160 {
161 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
162 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
163 
164 	gsr_bits = 0;
165 
166 	GCR = GCR_COLD_RST;
167 	GCR |= GCR_CDONE_IE|GCR_SDONE_IE;
168 	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
169 }
170 #endif
171 
172 #ifdef CONFIG_PXA27x
173 static inline void pxa_ac97_warm_pxa27x(void)
174 {
175 	gsr_bits = 0;
176 
177 	/* warm reset broken on Bulverde,
178 	   so manually keep AC97 reset high */
179 	set_resetgpio_mode(RESETGPIO_FORCE_HIGH);
180 	udelay(10);
181 	GCR |= GCR_WARM_RST;
182 	set_resetgpio_mode(RESETGPIO_NORMAL_ALTFUNC);
183 	udelay(500);
184 }
185 
186 static inline void pxa_ac97_cold_pxa27x(void)
187 {
188 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
189 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
190 
191 	gsr_bits = 0;
192 
193 	/* PXA27x Developers Manual section 13.5.2.2.1 */
194 	clk_enable(ac97conf_clk);
195 	udelay(5);
196 	clk_disable(ac97conf_clk);
197 	GCR = GCR_COLD_RST;
198 	udelay(50);
199 }
200 #endif
201 
202 #ifdef CONFIG_PXA3xx
203 static inline void pxa_ac97_warm_pxa3xx(void)
204 {
205 	int timeout = 100;
206 
207 	gsr_bits = 0;
208 
209 	/* Can't use interrupts */
210 	GCR |= GCR_WARM_RST;
211 	while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
212 		mdelay(1);
213 }
214 
215 static inline void pxa_ac97_cold_pxa3xx(void)
216 {
217 	int timeout = 1000;
218 
219 	/* Hold CLKBPB for 100us */
220 	GCR = 0;
221 	GCR = GCR_CLKBPB;
222 	udelay(100);
223 	GCR = 0;
224 
225 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
226 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
227 
228 	gsr_bits = 0;
229 
230 	/* Can't use interrupts on PXA3xx */
231 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
232 
233 	GCR = GCR_WARM_RST | GCR_COLD_RST;
234 	while (!(GSR & (GSR_PCR | GSR_SCR)) && timeout--)
235 		mdelay(10);
236 }
237 #endif
238 
239 bool pxa2xx_ac97_try_warm_reset(struct snd_ac97 *ac97)
240 {
241 	unsigned long gsr;
242 
243 #ifdef CONFIG_PXA25x
244 	if (cpu_is_pxa25x())
245 		pxa_ac97_warm_pxa25x();
246 	else
247 #endif
248 #ifdef CONFIG_PXA27x
249 	if (cpu_is_pxa27x())
250 		pxa_ac97_warm_pxa27x();
251 	else
252 #endif
253 #ifdef CONFIG_PXA3xx
254 	if (cpu_is_pxa3xx())
255 		pxa_ac97_warm_pxa3xx();
256 	else
257 #endif
258 		BUG();
259 	gsr = GSR | gsr_bits;
260 	if (!(gsr & (GSR_PCR | GSR_SCR))) {
261 		printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
262 				 __func__, gsr);
263 
264 		return false;
265 	}
266 
267 	return true;
268 }
269 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_warm_reset);
270 
271 bool pxa2xx_ac97_try_cold_reset(struct snd_ac97 *ac97)
272 {
273 	unsigned long gsr;
274 
275 #ifdef CONFIG_PXA25x
276 	if (cpu_is_pxa25x())
277 		pxa_ac97_cold_pxa25x();
278 	else
279 #endif
280 #ifdef CONFIG_PXA27x
281 	if (cpu_is_pxa27x())
282 		pxa_ac97_cold_pxa27x();
283 	else
284 #endif
285 #ifdef CONFIG_PXA3xx
286 	if (cpu_is_pxa3xx())
287 		pxa_ac97_cold_pxa3xx();
288 	else
289 #endif
290 		BUG();
291 
292 	gsr = GSR | gsr_bits;
293 	if (!(gsr & (GSR_PCR | GSR_SCR))) {
294 		printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
295 				 __func__, gsr);
296 
297 		return false;
298 	}
299 
300 	return true;
301 }
302 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_cold_reset);
303 
304 
305 void pxa2xx_ac97_finish_reset(struct snd_ac97 *ac97)
306 {
307 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
308 	GCR |= GCR_SDONE_IE|GCR_CDONE_IE;
309 }
310 EXPORT_SYMBOL_GPL(pxa2xx_ac97_finish_reset);
311 
312 static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
313 {
314 	long status;
315 
316 	status = GSR;
317 	if (status) {
318 		GSR = status;
319 		gsr_bits |= status;
320 		wake_up(&gsr_wq);
321 
322 		/* Although we don't use those we still need to clear them
323 		   since they tend to spuriously trigger when MMC is used
324 		   (hardware bug? go figure)... */
325 		if (cpu_is_pxa27x()) {
326 			MISR = MISR_EOC;
327 			PISR = PISR_EOC;
328 			MCSR = MCSR_EOC;
329 		}
330 
331 		return IRQ_HANDLED;
332 	}
333 
334 	return IRQ_NONE;
335 }
336 
337 #ifdef CONFIG_PM
338 int pxa2xx_ac97_hw_suspend(void)
339 {
340 	GCR |= GCR_ACLINK_OFF;
341 	clk_disable(ac97_clk);
342 	return 0;
343 }
344 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_suspend);
345 
346 int pxa2xx_ac97_hw_resume(void)
347 {
348 	if (cpu_is_pxa25x() || cpu_is_pxa27x()) {
349 		pxa_gpio_mode(GPIO31_SYNC_AC97_MD);
350 		pxa_gpio_mode(GPIO30_SDATA_OUT_AC97_MD);
351 		pxa_gpio_mode(GPIO28_BITCLK_AC97_MD);
352 		pxa_gpio_mode(GPIO29_SDATA_IN_AC97_MD);
353 	}
354 	if (cpu_is_pxa27x()) {
355 		/* Use GPIO 113 or 95 as AC97 Reset on Bulverde */
356 		set_resetgpio_mode(RESETGPIO_NORMAL_ALTFUNC);
357 	}
358 	clk_enable(ac97_clk);
359 	return 0;
360 }
361 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
362 #endif
363 
364 int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev)
365 {
366 	int ret;
367 	pxa2xx_audio_ops_t *pdata = dev->dev.platform_data;
368 
369 	if (pdata) {
370 		switch (pdata->reset_gpio) {
371 		case 95:
372 		case 113:
373 			reset_gpio = pdata->reset_gpio;
374 			break;
375 		case 0:
376 			reset_gpio = 113;
377 			break;
378 		case -1:
379 			break;
380 		default:
381 			dev_err(&dev->dev, "Invalid reset GPIO %d\n",
382 				pdata->reset_gpio);
383 		}
384 	} else {
385 		if (cpu_is_pxa27x())
386 			reset_gpio = 113;
387 	}
388 
389 	if (cpu_is_pxa25x() || cpu_is_pxa27x()) {
390 		pxa_gpio_mode(GPIO31_SYNC_AC97_MD);
391 		pxa_gpio_mode(GPIO30_SDATA_OUT_AC97_MD);
392 		pxa_gpio_mode(GPIO28_BITCLK_AC97_MD);
393 		pxa_gpio_mode(GPIO29_SDATA_IN_AC97_MD);
394 	}
395 
396 	if (cpu_is_pxa27x()) {
397 		/* Use GPIO 113 as AC97 Reset on Bulverde */
398 		set_resetgpio_mode(RESETGPIO_NORMAL_ALTFUNC);
399 		ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
400 		if (IS_ERR(ac97conf_clk)) {
401 			ret = PTR_ERR(ac97conf_clk);
402 			ac97conf_clk = NULL;
403 			goto err_conf;
404 		}
405 	}
406 
407 	ac97_clk = clk_get(&dev->dev, "AC97CLK");
408 	if (IS_ERR(ac97_clk)) {
409 		ret = PTR_ERR(ac97_clk);
410 		ac97_clk = NULL;
411 		goto err_clk;
412 	}
413 
414 	ret = clk_enable(ac97_clk);
415 	if (ret)
416 		goto err_clk2;
417 
418 	ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, IRQF_DISABLED, "AC97", NULL);
419 	if (ret < 0)
420 		goto err_irq;
421 
422 	return 0;
423 
424 err_irq:
425 	GCR |= GCR_ACLINK_OFF;
426 err_clk2:
427 	clk_put(ac97_clk);
428 	ac97_clk = NULL;
429 err_clk:
430 	if (ac97conf_clk) {
431 		clk_put(ac97conf_clk);
432 		ac97conf_clk = NULL;
433 	}
434 err_conf:
435 	return ret;
436 }
437 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);
438 
439 void pxa2xx_ac97_hw_remove(struct platform_device *dev)
440 {
441 	GCR |= GCR_ACLINK_OFF;
442 	free_irq(IRQ_AC97, NULL);
443 	if (ac97conf_clk) {
444 		clk_put(ac97conf_clk);
445 		ac97conf_clk = NULL;
446 	}
447 	clk_disable(ac97_clk);
448 	clk_put(ac97_clk);
449 	ac97_clk = NULL;
450 }
451 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_remove);
452 
453 MODULE_AUTHOR("Nicolas Pitre");
454 MODULE_DESCRIPTION("Intel/Marvell PXA sound library");
455 MODULE_LICENSE("GPL");
456 
457