xref: /openbmc/linux/sound/arm/pxa2xx-ac97-lib.c (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
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_OUT | GPIO_DFLT_LOW;
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 #ifdef CONFIG_PXA25x
242 	if (cpu_is_pxa25x())
243 		pxa_ac97_warm_pxa25x();
244 	else
245 #endif
246 #ifdef CONFIG_PXA27x
247 	if (cpu_is_pxa27x())
248 		pxa_ac97_warm_pxa27x();
249 	else
250 #endif
251 #ifdef CONFIG_PXA3xx
252 	if (cpu_is_pxa3xx())
253 		pxa_ac97_warm_pxa3xx();
254 	else
255 #endif
256 		BUG();
257 
258 	if (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR))) {
259 		printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
260 				 __func__, gsr_bits);
261 
262 		return false;
263 	}
264 
265 	return true;
266 }
267 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_warm_reset);
268 
269 bool pxa2xx_ac97_try_cold_reset(struct snd_ac97 *ac97)
270 {
271 #ifdef CONFIG_PXA25x
272 	if (cpu_is_pxa25x())
273 		pxa_ac97_cold_pxa25x();
274 	else
275 #endif
276 #ifdef CONFIG_PXA27x
277 	if (cpu_is_pxa27x())
278 		pxa_ac97_cold_pxa27x();
279 	else
280 #endif
281 #ifdef CONFIG_PXA3xx
282 	if (cpu_is_pxa3xx())
283 		pxa_ac97_cold_pxa3xx();
284 	else
285 #endif
286 		BUG();
287 
288 	if (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR))) {
289 		printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
290 				 __func__, gsr_bits);
291 
292 		return false;
293 	}
294 
295 	return true;
296 }
297 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_cold_reset);
298 
299 
300 void pxa2xx_ac97_finish_reset(struct snd_ac97 *ac97)
301 {
302 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
303 	GCR |= GCR_SDONE_IE|GCR_CDONE_IE;
304 }
305 EXPORT_SYMBOL_GPL(pxa2xx_ac97_finish_reset);
306 
307 static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
308 {
309 	long status;
310 
311 	status = GSR;
312 	if (status) {
313 		GSR = status;
314 		gsr_bits |= status;
315 		wake_up(&gsr_wq);
316 
317 		/* Although we don't use those we still need to clear them
318 		   since they tend to spuriously trigger when MMC is used
319 		   (hardware bug? go figure)... */
320 		if (cpu_is_pxa27x()) {
321 			MISR = MISR_EOC;
322 			PISR = PISR_EOC;
323 			MCSR = MCSR_EOC;
324 		}
325 
326 		return IRQ_HANDLED;
327 	}
328 
329 	return IRQ_NONE;
330 }
331 
332 #ifdef CONFIG_PM
333 int pxa2xx_ac97_hw_suspend(void)
334 {
335 	GCR |= GCR_ACLINK_OFF;
336 	clk_disable(ac97_clk);
337 	return 0;
338 }
339 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_suspend);
340 
341 int pxa2xx_ac97_hw_resume(void)
342 {
343 	if (cpu_is_pxa25x() || cpu_is_pxa27x()) {
344 		pxa_gpio_mode(GPIO31_SYNC_AC97_MD);
345 		pxa_gpio_mode(GPIO30_SDATA_OUT_AC97_MD);
346 		pxa_gpio_mode(GPIO28_BITCLK_AC97_MD);
347 		pxa_gpio_mode(GPIO29_SDATA_IN_AC97_MD);
348 	}
349 	if (cpu_is_pxa27x()) {
350 		/* Use GPIO 113 or 95 as AC97 Reset on Bulverde */
351 		set_resetgpio_mode(RESETGPIO_NORMAL_ALTFUNC);
352 	}
353 	clk_enable(ac97_clk);
354 	return 0;
355 }
356 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
357 #endif
358 
359 int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev)
360 {
361 	int ret;
362 	struct pxa2xx_ac97_platform_data *pdata = dev->dev.platform_data;
363 
364 	if (pdata) {
365 		switch (pdata->reset_gpio) {
366 		case 95:
367 		case 113:
368 			reset_gpio = pdata->reset_gpio;
369 			break;
370 		case 0:
371 			reset_gpio = 113;
372 			break;
373 		case -1:
374 			break;
375 		default:
376 			dev_err(&dev->dev, "Invalid reset GPIO %d\n",
377 				pdata->reset_gpio);
378 		}
379 	} else {
380 		if (cpu_is_pxa27x())
381 			reset_gpio = 113;
382 	}
383 
384 	if (cpu_is_pxa25x() || cpu_is_pxa27x()) {
385 		pxa_gpio_mode(GPIO31_SYNC_AC97_MD);
386 		pxa_gpio_mode(GPIO30_SDATA_OUT_AC97_MD);
387 		pxa_gpio_mode(GPIO28_BITCLK_AC97_MD);
388 		pxa_gpio_mode(GPIO29_SDATA_IN_AC97_MD);
389 	}
390 
391 	if (cpu_is_pxa27x()) {
392 		/* Use GPIO 113 as AC97 Reset on Bulverde */
393 		set_resetgpio_mode(RESETGPIO_NORMAL_ALTFUNC);
394 		ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
395 		if (IS_ERR(ac97conf_clk)) {
396 			ret = PTR_ERR(ac97conf_clk);
397 			ac97conf_clk = NULL;
398 			goto err_conf;
399 		}
400 	}
401 
402 	ac97_clk = clk_get(&dev->dev, "AC97CLK");
403 	if (IS_ERR(ac97_clk)) {
404 		ret = PTR_ERR(ac97_clk);
405 		ac97_clk = NULL;
406 		goto err_clk;
407 	}
408 
409 	ret = clk_enable(ac97_clk);
410 	if (ret)
411 		goto err_clk2;
412 
413 	ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, IRQF_DISABLED, "AC97", NULL);
414 	if (ret < 0)
415 		goto err_irq;
416 
417 	return 0;
418 
419 err_irq:
420 	GCR |= GCR_ACLINK_OFF;
421 err_clk2:
422 	clk_put(ac97_clk);
423 	ac97_clk = NULL;
424 err_clk:
425 	if (ac97conf_clk) {
426 		clk_put(ac97conf_clk);
427 		ac97conf_clk = NULL;
428 	}
429 err_conf:
430 	return ret;
431 }
432 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);
433 
434 void pxa2xx_ac97_hw_remove(struct platform_device *dev)
435 {
436 	GCR |= GCR_ACLINK_OFF;
437 	free_irq(IRQ_AC97, NULL);
438 	if (ac97conf_clk) {
439 		clk_put(ac97conf_clk);
440 		ac97conf_clk = NULL;
441 	}
442 	clk_disable(ac97_clk);
443 	clk_put(ac97_clk);
444 	ac97_clk = NULL;
445 }
446 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_remove);
447 
448 MODULE_AUTHOR("Nicolas Pitre");
449 MODULE_DESCRIPTION("Intel/Marvell PXA sound library");
450 MODULE_LICENSE("GPL");
451 
452