xref: /openbmc/linux/sound/arm/pxa2xx-ac97-lib.c (revision 3a9a231d)
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/audio.h>
26 
27 static DEFINE_MUTEX(car_mutex);
28 static DECLARE_WAIT_QUEUE_HEAD(gsr_wq);
29 static volatile long gsr_bits;
30 static struct clk *ac97_clk;
31 static struct clk *ac97conf_clk;
32 static int reset_gpio;
33 
34 extern void pxa27x_assert_ac97reset(int reset_gpio, int on);
35 
36 /*
37  * Beware PXA27x bugs:
38  *
39  *   o Slot 12 read from modem space will hang controller.
40  *   o CDONE, SDONE interrupt fails after any slot 12 IO.
41  *
42  * We therefore have an hybrid approach for waiting on SDONE (interrupt or
43  * 1 jiffy timeout if interrupt never comes).
44  */
45 
46 unsigned short pxa2xx_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
47 {
48 	unsigned short val = -1;
49 	volatile u32 *reg_addr;
50 
51 	mutex_lock(&car_mutex);
52 
53 	/* set up primary or secondary codec space */
54 	if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
55 		reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
56 	else
57 		reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
58 	reg_addr += (reg >> 1);
59 
60 	/* start read access across the ac97 link */
61 	GSR = GSR_CDONE | GSR_SDONE;
62 	gsr_bits = 0;
63 	val = *reg_addr;
64 	if (reg == AC97_GPIO_STATUS)
65 		goto out;
66 	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1) <= 0 &&
67 	    !((GSR | gsr_bits) & GSR_SDONE)) {
68 		printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n",
69 				__func__, reg, GSR | gsr_bits);
70 		val = -1;
71 		goto out;
72 	}
73 
74 	/* valid data now */
75 	GSR = GSR_CDONE | GSR_SDONE;
76 	gsr_bits = 0;
77 	val = *reg_addr;
78 	/* but we've just started another cycle... */
79 	wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1);
80 
81 out:	mutex_unlock(&car_mutex);
82 	return val;
83 }
84 EXPORT_SYMBOL_GPL(pxa2xx_ac97_read);
85 
86 void pxa2xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
87 			unsigned short val)
88 {
89 	volatile u32 *reg_addr;
90 
91 	mutex_lock(&car_mutex);
92 
93 	/* set up primary or secondary codec space */
94 	if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
95 		reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
96 	else
97 		reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
98 	reg_addr += (reg >> 1);
99 
100 	GSR = GSR_CDONE | GSR_SDONE;
101 	gsr_bits = 0;
102 	*reg_addr = val;
103 	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_CDONE, 1) <= 0 &&
104 	    !((GSR | gsr_bits) & GSR_CDONE))
105 		printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n",
106 				__func__, reg, GSR | gsr_bits);
107 
108 	mutex_unlock(&car_mutex);
109 }
110 EXPORT_SYMBOL_GPL(pxa2xx_ac97_write);
111 
112 #ifdef CONFIG_PXA25x
113 static inline void pxa_ac97_warm_pxa25x(void)
114 {
115 	gsr_bits = 0;
116 
117 	GCR |= GCR_WARM_RST | GCR_PRIRDY_IEN | GCR_SECRDY_IEN;
118 	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
119 }
120 
121 static inline void pxa_ac97_cold_pxa25x(void)
122 {
123 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
124 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
125 
126 	gsr_bits = 0;
127 
128 	GCR = GCR_COLD_RST;
129 	GCR |= GCR_CDONE_IE|GCR_SDONE_IE;
130 	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
131 }
132 #endif
133 
134 #ifdef CONFIG_PXA27x
135 static inline void pxa_ac97_warm_pxa27x(void)
136 {
137 	gsr_bits = 0;
138 
139 	/* warm reset broken on Bulverde, so manually keep AC97 reset high */
140 	pxa27x_assert_ac97reset(reset_gpio, 1);
141 	udelay(10);
142 	GCR |= GCR_WARM_RST;
143 	pxa27x_assert_ac97reset(reset_gpio, 0);
144 	udelay(500);
145 }
146 
147 static inline void pxa_ac97_cold_pxa27x(void)
148 {
149 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
150 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
151 
152 	gsr_bits = 0;
153 
154 	/* PXA27x Developers Manual section 13.5.2.2.1 */
155 	clk_enable(ac97conf_clk);
156 	udelay(5);
157 	clk_disable(ac97conf_clk);
158 	GCR = GCR_COLD_RST;
159 	udelay(50);
160 }
161 #endif
162 
163 #ifdef CONFIG_PXA3xx
164 static inline void pxa_ac97_warm_pxa3xx(void)
165 {
166 	int timeout = 100;
167 
168 	gsr_bits = 0;
169 
170 	/* Can't use interrupts */
171 	GCR |= GCR_WARM_RST;
172 	while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
173 		mdelay(1);
174 }
175 
176 static inline void pxa_ac97_cold_pxa3xx(void)
177 {
178 	int timeout = 1000;
179 
180 	/* Hold CLKBPB for 100us */
181 	GCR = 0;
182 	GCR = GCR_CLKBPB;
183 	udelay(100);
184 	GCR = 0;
185 
186 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
187 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
188 
189 	gsr_bits = 0;
190 
191 	/* Can't use interrupts on PXA3xx */
192 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
193 
194 	GCR = GCR_WARM_RST | GCR_COLD_RST;
195 	while (!(GSR & (GSR_PCR | GSR_SCR)) && timeout--)
196 		mdelay(10);
197 }
198 #endif
199 
200 bool pxa2xx_ac97_try_warm_reset(struct snd_ac97 *ac97)
201 {
202 	unsigned long gsr;
203 
204 #ifdef CONFIG_PXA25x
205 	if (cpu_is_pxa25x())
206 		pxa_ac97_warm_pxa25x();
207 	else
208 #endif
209 #ifdef CONFIG_PXA27x
210 	if (cpu_is_pxa27x())
211 		pxa_ac97_warm_pxa27x();
212 	else
213 #endif
214 #ifdef CONFIG_PXA3xx
215 	if (cpu_is_pxa3xx())
216 		pxa_ac97_warm_pxa3xx();
217 	else
218 #endif
219 		BUG();
220 	gsr = GSR | gsr_bits;
221 	if (!(gsr & (GSR_PCR | GSR_SCR))) {
222 		printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
223 				 __func__, gsr);
224 
225 		return false;
226 	}
227 
228 	return true;
229 }
230 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_warm_reset);
231 
232 bool pxa2xx_ac97_try_cold_reset(struct snd_ac97 *ac97)
233 {
234 	unsigned long gsr;
235 
236 #ifdef CONFIG_PXA25x
237 	if (cpu_is_pxa25x())
238 		pxa_ac97_cold_pxa25x();
239 	else
240 #endif
241 #ifdef CONFIG_PXA27x
242 	if (cpu_is_pxa27x())
243 		pxa_ac97_cold_pxa27x();
244 	else
245 #endif
246 #ifdef CONFIG_PXA3xx
247 	if (cpu_is_pxa3xx())
248 		pxa_ac97_cold_pxa3xx();
249 	else
250 #endif
251 		BUG();
252 
253 	gsr = GSR | gsr_bits;
254 	if (!(gsr & (GSR_PCR | GSR_SCR))) {
255 		printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
256 				 __func__, gsr);
257 
258 		return false;
259 	}
260 
261 	return true;
262 }
263 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_cold_reset);
264 
265 
266 void pxa2xx_ac97_finish_reset(struct snd_ac97 *ac97)
267 {
268 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
269 	GCR |= GCR_SDONE_IE|GCR_CDONE_IE;
270 }
271 EXPORT_SYMBOL_GPL(pxa2xx_ac97_finish_reset);
272 
273 static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
274 {
275 	long status;
276 
277 	status = GSR;
278 	if (status) {
279 		GSR = status;
280 		gsr_bits |= status;
281 		wake_up(&gsr_wq);
282 
283 		/* Although we don't use those we still need to clear them
284 		   since they tend to spuriously trigger when MMC is used
285 		   (hardware bug? go figure)... */
286 		if (cpu_is_pxa27x()) {
287 			MISR = MISR_EOC;
288 			PISR = PISR_EOC;
289 			MCSR = MCSR_EOC;
290 		}
291 
292 		return IRQ_HANDLED;
293 	}
294 
295 	return IRQ_NONE;
296 }
297 
298 #ifdef CONFIG_PM
299 int pxa2xx_ac97_hw_suspend(void)
300 {
301 	GCR |= GCR_ACLINK_OFF;
302 	clk_disable(ac97_clk);
303 	return 0;
304 }
305 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_suspend);
306 
307 int pxa2xx_ac97_hw_resume(void)
308 {
309 	clk_enable(ac97_clk);
310 	return 0;
311 }
312 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
313 #endif
314 
315 int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev)
316 {
317 	int ret;
318 	pxa2xx_audio_ops_t *pdata = dev->dev.platform_data;
319 
320 	if (pdata) {
321 		switch (pdata->reset_gpio) {
322 		case 95:
323 		case 113:
324 			reset_gpio = pdata->reset_gpio;
325 			break;
326 		case 0:
327 			reset_gpio = 113;
328 			break;
329 		case -1:
330 			break;
331 		default:
332 			dev_err(&dev->dev, "Invalid reset GPIO %d\n",
333 				pdata->reset_gpio);
334 		}
335 	} else {
336 		if (cpu_is_pxa27x())
337 			reset_gpio = 113;
338 	}
339 
340 	if (cpu_is_pxa27x()) {
341 		/* Use GPIO 113 as AC97 Reset on Bulverde */
342 		pxa27x_assert_ac97reset(reset_gpio, 0);
343 		ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
344 		if (IS_ERR(ac97conf_clk)) {
345 			ret = PTR_ERR(ac97conf_clk);
346 			ac97conf_clk = NULL;
347 			goto err_conf;
348 		}
349 	}
350 
351 	ac97_clk = clk_get(&dev->dev, "AC97CLK");
352 	if (IS_ERR(ac97_clk)) {
353 		ret = PTR_ERR(ac97_clk);
354 		ac97_clk = NULL;
355 		goto err_clk;
356 	}
357 
358 	ret = clk_enable(ac97_clk);
359 	if (ret)
360 		goto err_clk2;
361 
362 	ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, 0, "AC97", NULL);
363 	if (ret < 0)
364 		goto err_irq;
365 
366 	return 0;
367 
368 err_irq:
369 	GCR |= GCR_ACLINK_OFF;
370 err_clk2:
371 	clk_put(ac97_clk);
372 	ac97_clk = NULL;
373 err_clk:
374 	if (ac97conf_clk) {
375 		clk_put(ac97conf_clk);
376 		ac97conf_clk = NULL;
377 	}
378 err_conf:
379 	return ret;
380 }
381 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);
382 
383 void pxa2xx_ac97_hw_remove(struct platform_device *dev)
384 {
385 	GCR |= GCR_ACLINK_OFF;
386 	free_irq(IRQ_AC97, NULL);
387 	if (ac97conf_clk) {
388 		clk_put(ac97conf_clk);
389 		ac97conf_clk = NULL;
390 	}
391 	clk_disable(ac97_clk);
392 	clk_put(ac97_clk);
393 	ac97_clk = NULL;
394 }
395 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_remove);
396 
397 MODULE_AUTHOR("Nicolas Pitre");
398 MODULE_DESCRIPTION("Intel/Marvell PXA sound library");
399 MODULE_LICENSE("GPL");
400 
401