xref: /openbmc/linux/sound/arm/pxa2xx-ac97-lib.c (revision 95e9fd10)
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 #include <linux/module.h>
20 #include <linux/io.h>
21 
22 #include <sound/ac97_codec.h>
23 #include <sound/pxa2xx-lib.h>
24 
25 #include <mach/irqs.h>
26 #include <mach/regs-ac97.h>
27 #include <mach/audio.h>
28 
29 static DEFINE_MUTEX(car_mutex);
30 static DECLARE_WAIT_QUEUE_HEAD(gsr_wq);
31 static volatile long gsr_bits;
32 static struct clk *ac97_clk;
33 static struct clk *ac97conf_clk;
34 static int reset_gpio;
35 
36 extern void pxa27x_assert_ac97reset(int reset_gpio, int on);
37 
38 /*
39  * Beware PXA27x bugs:
40  *
41  *   o Slot 12 read from modem space will hang controller.
42  *   o CDONE, SDONE interrupt fails after any slot 12 IO.
43  *
44  * We therefore have an hybrid approach for waiting on SDONE (interrupt or
45  * 1 jiffy timeout if interrupt never comes).
46  */
47 
48 unsigned short pxa2xx_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
49 {
50 	unsigned short val = -1;
51 	volatile u32 *reg_addr;
52 
53 	mutex_lock(&car_mutex);
54 
55 	/* set up primary or secondary codec space */
56 	if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
57 		reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
58 	else
59 		reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
60 	reg_addr += (reg >> 1);
61 
62 	/* start read access across the ac97 link */
63 	GSR = GSR_CDONE | GSR_SDONE;
64 	gsr_bits = 0;
65 	val = *reg_addr;
66 	if (reg == AC97_GPIO_STATUS)
67 		goto out;
68 	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1) <= 0 &&
69 	    !((GSR | gsr_bits) & GSR_SDONE)) {
70 		printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n",
71 				__func__, reg, GSR | gsr_bits);
72 		val = -1;
73 		goto out;
74 	}
75 
76 	/* valid data now */
77 	GSR = GSR_CDONE | GSR_SDONE;
78 	gsr_bits = 0;
79 	val = *reg_addr;
80 	/* but we've just started another cycle... */
81 	wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1);
82 
83 out:	mutex_unlock(&car_mutex);
84 	return val;
85 }
86 EXPORT_SYMBOL_GPL(pxa2xx_ac97_read);
87 
88 void pxa2xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
89 			unsigned short val)
90 {
91 	volatile u32 *reg_addr;
92 
93 	mutex_lock(&car_mutex);
94 
95 	/* set up primary or secondary codec space */
96 	if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
97 		reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
98 	else
99 		reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
100 	reg_addr += (reg >> 1);
101 
102 	GSR = GSR_CDONE | GSR_SDONE;
103 	gsr_bits = 0;
104 	*reg_addr = val;
105 	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_CDONE, 1) <= 0 &&
106 	    !((GSR | gsr_bits) & GSR_CDONE))
107 		printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n",
108 				__func__, reg, GSR | gsr_bits);
109 
110 	mutex_unlock(&car_mutex);
111 }
112 EXPORT_SYMBOL_GPL(pxa2xx_ac97_write);
113 
114 #ifdef CONFIG_PXA25x
115 static inline void pxa_ac97_warm_pxa25x(void)
116 {
117 	gsr_bits = 0;
118 
119 	GCR |= GCR_WARM_RST | GCR_PRIRDY_IEN | GCR_SECRDY_IEN;
120 	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
121 }
122 
123 static inline void pxa_ac97_cold_pxa25x(void)
124 {
125 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
126 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
127 
128 	gsr_bits = 0;
129 
130 	GCR = GCR_COLD_RST;
131 	GCR |= GCR_CDONE_IE|GCR_SDONE_IE;
132 	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
133 }
134 #endif
135 
136 #ifdef CONFIG_PXA27x
137 static inline void pxa_ac97_warm_pxa27x(void)
138 {
139 	gsr_bits = 0;
140 
141 	/* warm reset broken on Bulverde, so manually keep AC97 reset high */
142 	pxa27x_assert_ac97reset(reset_gpio, 1);
143 	udelay(10);
144 	GCR |= GCR_WARM_RST;
145 	pxa27x_assert_ac97reset(reset_gpio, 0);
146 	udelay(500);
147 }
148 
149 static inline void pxa_ac97_cold_pxa27x(void)
150 {
151 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
152 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
153 
154 	gsr_bits = 0;
155 
156 	/* PXA27x Developers Manual section 13.5.2.2.1 */
157 	clk_enable(ac97conf_clk);
158 	udelay(5);
159 	clk_disable(ac97conf_clk);
160 	GCR = GCR_COLD_RST;
161 	udelay(50);
162 }
163 #endif
164 
165 #ifdef CONFIG_PXA3xx
166 static inline void pxa_ac97_warm_pxa3xx(void)
167 {
168 	int timeout = 100;
169 
170 	gsr_bits = 0;
171 
172 	/* Can't use interrupts */
173 	GCR |= GCR_WARM_RST;
174 	while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
175 		mdelay(1);
176 }
177 
178 static inline void pxa_ac97_cold_pxa3xx(void)
179 {
180 	int timeout = 1000;
181 
182 	/* Hold CLKBPB for 100us */
183 	GCR = 0;
184 	GCR = GCR_CLKBPB;
185 	udelay(100);
186 	GCR = 0;
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 	/* Can't use interrupts on PXA3xx */
194 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
195 
196 	GCR = GCR_WARM_RST | GCR_COLD_RST;
197 	while (!(GSR & (GSR_PCR | GSR_SCR)) && timeout--)
198 		mdelay(10);
199 }
200 #endif
201 
202 bool pxa2xx_ac97_try_warm_reset(struct snd_ac97 *ac97)
203 {
204 	unsigned long gsr;
205 
206 #ifdef CONFIG_PXA25x
207 	if (cpu_is_pxa25x())
208 		pxa_ac97_warm_pxa25x();
209 	else
210 #endif
211 #ifdef CONFIG_PXA27x
212 	if (cpu_is_pxa27x())
213 		pxa_ac97_warm_pxa27x();
214 	else
215 #endif
216 #ifdef CONFIG_PXA3xx
217 	if (cpu_is_pxa3xx())
218 		pxa_ac97_warm_pxa3xx();
219 	else
220 #endif
221 		BUG();
222 	gsr = GSR | gsr_bits;
223 	if (!(gsr & (GSR_PCR | GSR_SCR))) {
224 		printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
225 				 __func__, gsr);
226 
227 		return false;
228 	}
229 
230 	return true;
231 }
232 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_warm_reset);
233 
234 bool pxa2xx_ac97_try_cold_reset(struct snd_ac97 *ac97)
235 {
236 	unsigned long gsr;
237 
238 #ifdef CONFIG_PXA25x
239 	if (cpu_is_pxa25x())
240 		pxa_ac97_cold_pxa25x();
241 	else
242 #endif
243 #ifdef CONFIG_PXA27x
244 	if (cpu_is_pxa27x())
245 		pxa_ac97_cold_pxa27x();
246 	else
247 #endif
248 #ifdef CONFIG_PXA3xx
249 	if (cpu_is_pxa3xx())
250 		pxa_ac97_cold_pxa3xx();
251 	else
252 #endif
253 		BUG();
254 
255 	gsr = GSR | gsr_bits;
256 	if (!(gsr & (GSR_PCR | GSR_SCR))) {
257 		printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
258 				 __func__, gsr);
259 
260 		return false;
261 	}
262 
263 	return true;
264 }
265 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_cold_reset);
266 
267 
268 void pxa2xx_ac97_finish_reset(struct snd_ac97 *ac97)
269 {
270 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
271 	GCR |= GCR_SDONE_IE|GCR_CDONE_IE;
272 }
273 EXPORT_SYMBOL_GPL(pxa2xx_ac97_finish_reset);
274 
275 static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
276 {
277 	long status;
278 
279 	status = GSR;
280 	if (status) {
281 		GSR = status;
282 		gsr_bits |= status;
283 		wake_up(&gsr_wq);
284 
285 		/* Although we don't use those we still need to clear them
286 		   since they tend to spuriously trigger when MMC is used
287 		   (hardware bug? go figure)... */
288 		if (cpu_is_pxa27x()) {
289 			MISR = MISR_EOC;
290 			PISR = PISR_EOC;
291 			MCSR = MCSR_EOC;
292 		}
293 
294 		return IRQ_HANDLED;
295 	}
296 
297 	return IRQ_NONE;
298 }
299 
300 #ifdef CONFIG_PM
301 int pxa2xx_ac97_hw_suspend(void)
302 {
303 	GCR |= GCR_ACLINK_OFF;
304 	clk_disable(ac97_clk);
305 	return 0;
306 }
307 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_suspend);
308 
309 int pxa2xx_ac97_hw_resume(void)
310 {
311 	clk_enable(ac97_clk);
312 	return 0;
313 }
314 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
315 #endif
316 
317 int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev)
318 {
319 	int ret;
320 	pxa2xx_audio_ops_t *pdata = dev->dev.platform_data;
321 
322 	if (pdata) {
323 		switch (pdata->reset_gpio) {
324 		case 95:
325 		case 113:
326 			reset_gpio = pdata->reset_gpio;
327 			break;
328 		case 0:
329 			reset_gpio = 113;
330 			break;
331 		case -1:
332 			break;
333 		default:
334 			dev_err(&dev->dev, "Invalid reset GPIO %d\n",
335 				pdata->reset_gpio);
336 		}
337 	} else {
338 		if (cpu_is_pxa27x())
339 			reset_gpio = 113;
340 	}
341 
342 	if (cpu_is_pxa27x()) {
343 		/* Use GPIO 113 as AC97 Reset on Bulverde */
344 		pxa27x_assert_ac97reset(reset_gpio, 0);
345 		ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
346 		if (IS_ERR(ac97conf_clk)) {
347 			ret = PTR_ERR(ac97conf_clk);
348 			ac97conf_clk = NULL;
349 			goto err_conf;
350 		}
351 	}
352 
353 	ac97_clk = clk_get(&dev->dev, "AC97CLK");
354 	if (IS_ERR(ac97_clk)) {
355 		ret = PTR_ERR(ac97_clk);
356 		ac97_clk = NULL;
357 		goto err_clk;
358 	}
359 
360 	ret = clk_enable(ac97_clk);
361 	if (ret)
362 		goto err_clk2;
363 
364 	ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, 0, "AC97", NULL);
365 	if (ret < 0)
366 		goto err_irq;
367 
368 	return 0;
369 
370 err_irq:
371 	GCR |= GCR_ACLINK_OFF;
372 err_clk2:
373 	clk_put(ac97_clk);
374 	ac97_clk = NULL;
375 err_clk:
376 	if (ac97conf_clk) {
377 		clk_put(ac97conf_clk);
378 		ac97conf_clk = NULL;
379 	}
380 err_conf:
381 	return ret;
382 }
383 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);
384 
385 void pxa2xx_ac97_hw_remove(struct platform_device *dev)
386 {
387 	GCR |= GCR_ACLINK_OFF;
388 	free_irq(IRQ_AC97, NULL);
389 	if (ac97conf_clk) {
390 		clk_put(ac97conf_clk);
391 		ac97conf_clk = NULL;
392 	}
393 	clk_disable(ac97_clk);
394 	clk_put(ac97_clk);
395 	ac97_clk = NULL;
396 }
397 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_remove);
398 
399 MODULE_AUTHOR("Nicolas Pitre");
400 MODULE_DESCRIPTION("Intel/Marvell PXA sound library");
401 MODULE_LICENSE("GPL");
402 
403