xref: /openbmc/linux/sound/arm/pxa2xx-ac97-lib.c (revision e23feb16)
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 #include <linux/gpio.h>
22 
23 #include <sound/ac97_codec.h>
24 #include <sound/pxa2xx-lib.h>
25 
26 #include <mach/irqs.h>
27 #include <mach/regs-ac97.h>
28 #include <mach/audio.h>
29 
30 static DEFINE_MUTEX(car_mutex);
31 static DECLARE_WAIT_QUEUE_HEAD(gsr_wq);
32 static volatile long gsr_bits;
33 static struct clk *ac97_clk;
34 static struct clk *ac97conf_clk;
35 static int reset_gpio;
36 
37 extern void pxa27x_configure_ac97reset(int reset_gpio, bool to_gpio);
38 
39 /*
40  * Beware PXA27x bugs:
41  *
42  *   o Slot 12 read from modem space will hang controller.
43  *   o CDONE, SDONE interrupt fails after any slot 12 IO.
44  *
45  * We therefore have an hybrid approach for waiting on SDONE (interrupt or
46  * 1 jiffy timeout if interrupt never comes).
47  */
48 
49 unsigned short pxa2xx_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
50 {
51 	unsigned short val = -1;
52 	volatile u32 *reg_addr;
53 
54 	mutex_lock(&car_mutex);
55 
56 	/* set up primary or secondary codec space */
57 	if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
58 		reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
59 	else
60 		reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
61 	reg_addr += (reg >> 1);
62 
63 	/* start read access across the ac97 link */
64 	GSR = GSR_CDONE | GSR_SDONE;
65 	gsr_bits = 0;
66 	val = *reg_addr;
67 	if (reg == AC97_GPIO_STATUS)
68 		goto out;
69 	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1) <= 0 &&
70 	    !((GSR | gsr_bits) & GSR_SDONE)) {
71 		printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n",
72 				__func__, reg, GSR | gsr_bits);
73 		val = -1;
74 		goto out;
75 	}
76 
77 	/* valid data now */
78 	GSR = GSR_CDONE | GSR_SDONE;
79 	gsr_bits = 0;
80 	val = *reg_addr;
81 	/* but we've just started another cycle... */
82 	wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1);
83 
84 out:	mutex_unlock(&car_mutex);
85 	return val;
86 }
87 EXPORT_SYMBOL_GPL(pxa2xx_ac97_read);
88 
89 void pxa2xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
90 			unsigned short val)
91 {
92 	volatile u32 *reg_addr;
93 
94 	mutex_lock(&car_mutex);
95 
96 	/* set up primary or secondary codec space */
97 	if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
98 		reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
99 	else
100 		reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
101 	reg_addr += (reg >> 1);
102 
103 	GSR = GSR_CDONE | GSR_SDONE;
104 	gsr_bits = 0;
105 	*reg_addr = val;
106 	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_CDONE, 1) <= 0 &&
107 	    !((GSR | gsr_bits) & GSR_CDONE))
108 		printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n",
109 				__func__, reg, GSR | gsr_bits);
110 
111 	mutex_unlock(&car_mutex);
112 }
113 EXPORT_SYMBOL_GPL(pxa2xx_ac97_write);
114 
115 #ifdef CONFIG_PXA25x
116 static inline void pxa_ac97_warm_pxa25x(void)
117 {
118 	gsr_bits = 0;
119 
120 	GCR |= GCR_WARM_RST | GCR_PRIRDY_IEN | GCR_SECRDY_IEN;
121 	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
122 }
123 
124 static inline void pxa_ac97_cold_pxa25x(void)
125 {
126 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
127 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
128 
129 	gsr_bits = 0;
130 
131 	GCR = GCR_COLD_RST;
132 	GCR |= GCR_CDONE_IE|GCR_SDONE_IE;
133 	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
134 }
135 #endif
136 
137 #ifdef CONFIG_PXA27x
138 static inline void pxa_ac97_warm_pxa27x(void)
139 {
140 	gsr_bits = 0;
141 
142 	/* warm reset broken on Bulverde, so manually keep AC97 reset high */
143 	pxa27x_configure_ac97reset(reset_gpio, true);
144 	udelay(10);
145 	GCR |= GCR_WARM_RST;
146 	pxa27x_configure_ac97reset(reset_gpio, false);
147 	udelay(500);
148 }
149 
150 static inline void pxa_ac97_cold_pxa27x(void)
151 {
152 	unsigned int timeout;
153 
154 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
155 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
156 
157 	gsr_bits = 0;
158 
159 	/* PXA27x Developers Manual section 13.5.2.2.1 */
160 	clk_enable(ac97conf_clk);
161 	udelay(5);
162 	clk_disable(ac97conf_clk);
163 	GCR = GCR_COLD_RST | GCR_WARM_RST;
164 	timeout = 100;     /* wait for the codec-ready bit to be set */
165 	while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
166 		mdelay(1);
167 }
168 #endif
169 
170 #ifdef CONFIG_PXA3xx
171 static inline void pxa_ac97_warm_pxa3xx(void)
172 {
173 	int timeout = 100;
174 
175 	gsr_bits = 0;
176 
177 	/* Can't use interrupts */
178 	GCR |= GCR_WARM_RST;
179 	while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
180 		mdelay(1);
181 }
182 
183 static inline void pxa_ac97_cold_pxa3xx(void)
184 {
185 	int timeout = 1000;
186 
187 	/* Hold CLKBPB for 100us */
188 	GCR = 0;
189 	GCR = GCR_CLKBPB;
190 	udelay(100);
191 	GCR = 0;
192 
193 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
194 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
195 
196 	gsr_bits = 0;
197 
198 	/* Can't use interrupts on PXA3xx */
199 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
200 
201 	GCR = GCR_WARM_RST | GCR_COLD_RST;
202 	while (!(GSR & (GSR_PCR | GSR_SCR)) && timeout--)
203 		mdelay(10);
204 }
205 #endif
206 
207 bool pxa2xx_ac97_try_warm_reset(struct snd_ac97 *ac97)
208 {
209 	unsigned long gsr;
210 
211 #ifdef CONFIG_PXA25x
212 	if (cpu_is_pxa25x())
213 		pxa_ac97_warm_pxa25x();
214 	else
215 #endif
216 #ifdef CONFIG_PXA27x
217 	if (cpu_is_pxa27x())
218 		pxa_ac97_warm_pxa27x();
219 	else
220 #endif
221 #ifdef CONFIG_PXA3xx
222 	if (cpu_is_pxa3xx())
223 		pxa_ac97_warm_pxa3xx();
224 	else
225 #endif
226 		BUG();
227 	gsr = GSR | gsr_bits;
228 	if (!(gsr & (GSR_PCR | GSR_SCR))) {
229 		printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
230 				 __func__, gsr);
231 
232 		return false;
233 	}
234 
235 	return true;
236 }
237 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_warm_reset);
238 
239 bool pxa2xx_ac97_try_cold_reset(struct snd_ac97 *ac97)
240 {
241 	unsigned long gsr;
242 
243 #ifdef CONFIG_PXA25x
244 	if (cpu_is_pxa25x())
245 		pxa_ac97_cold_pxa25x();
246 	else
247 #endif
248 #ifdef CONFIG_PXA27x
249 	if (cpu_is_pxa27x())
250 		pxa_ac97_cold_pxa27x();
251 	else
252 #endif
253 #ifdef CONFIG_PXA3xx
254 	if (cpu_is_pxa3xx())
255 		pxa_ac97_cold_pxa3xx();
256 	else
257 #endif
258 		BUG();
259 
260 	gsr = GSR | gsr_bits;
261 	if (!(gsr & (GSR_PCR | GSR_SCR))) {
262 		printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
263 				 __func__, gsr);
264 
265 		return false;
266 	}
267 
268 	return true;
269 }
270 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_cold_reset);
271 
272 
273 void pxa2xx_ac97_finish_reset(struct snd_ac97 *ac97)
274 {
275 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
276 	GCR |= GCR_SDONE_IE|GCR_CDONE_IE;
277 }
278 EXPORT_SYMBOL_GPL(pxa2xx_ac97_finish_reset);
279 
280 static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
281 {
282 	long status;
283 
284 	status = GSR;
285 	if (status) {
286 		GSR = status;
287 		gsr_bits |= status;
288 		wake_up(&gsr_wq);
289 
290 		/* Although we don't use those we still need to clear them
291 		   since they tend to spuriously trigger when MMC is used
292 		   (hardware bug? go figure)... */
293 		if (cpu_is_pxa27x()) {
294 			MISR = MISR_EOC;
295 			PISR = PISR_EOC;
296 			MCSR = MCSR_EOC;
297 		}
298 
299 		return IRQ_HANDLED;
300 	}
301 
302 	return IRQ_NONE;
303 }
304 
305 #ifdef CONFIG_PM
306 int pxa2xx_ac97_hw_suspend(void)
307 {
308 	GCR |= GCR_ACLINK_OFF;
309 	clk_disable(ac97_clk);
310 	return 0;
311 }
312 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_suspend);
313 
314 int pxa2xx_ac97_hw_resume(void)
315 {
316 	clk_enable(ac97_clk);
317 	return 0;
318 }
319 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
320 #endif
321 
322 int pxa2xx_ac97_hw_probe(struct platform_device *dev)
323 {
324 	int ret;
325 	pxa2xx_audio_ops_t *pdata = dev->dev.platform_data;
326 
327 	if (pdata) {
328 		switch (pdata->reset_gpio) {
329 		case 95:
330 		case 113:
331 			reset_gpio = pdata->reset_gpio;
332 			break;
333 		case 0:
334 			reset_gpio = 113;
335 			break;
336 		case -1:
337 			break;
338 		default:
339 			dev_err(&dev->dev, "Invalid reset GPIO %d\n",
340 				pdata->reset_gpio);
341 		}
342 	} else {
343 		if (cpu_is_pxa27x())
344 			reset_gpio = 113;
345 	}
346 
347 	if (cpu_is_pxa27x()) {
348 		/*
349 		 * This gpio is needed for a work-around to a bug in the ac97
350 		 * controller during warm reset.  The direction and level is set
351 		 * here so that it is an output driven high when switching from
352 		 * AC97_nRESET alt function to generic gpio.
353 		 */
354 		ret = gpio_request_one(reset_gpio, GPIOF_OUT_INIT_HIGH,
355 				       "pxa27x ac97 reset");
356 		if (ret < 0) {
357 			pr_err("%s: gpio_request_one() failed: %d\n",
358 			       __func__, ret);
359 			goto err_conf;
360 		}
361 		pxa27x_configure_ac97reset(reset_gpio, false);
362 
363 		ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
364 		if (IS_ERR(ac97conf_clk)) {
365 			ret = PTR_ERR(ac97conf_clk);
366 			ac97conf_clk = NULL;
367 			goto err_conf;
368 		}
369 	}
370 
371 	ac97_clk = clk_get(&dev->dev, "AC97CLK");
372 	if (IS_ERR(ac97_clk)) {
373 		ret = PTR_ERR(ac97_clk);
374 		ac97_clk = NULL;
375 		goto err_clk;
376 	}
377 
378 	ret = clk_enable(ac97_clk);
379 	if (ret)
380 		goto err_clk2;
381 
382 	ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, 0, "AC97", NULL);
383 	if (ret < 0)
384 		goto err_irq;
385 
386 	return 0;
387 
388 err_irq:
389 	GCR |= GCR_ACLINK_OFF;
390 err_clk2:
391 	clk_put(ac97_clk);
392 	ac97_clk = NULL;
393 err_clk:
394 	if (ac97conf_clk) {
395 		clk_put(ac97conf_clk);
396 		ac97conf_clk = NULL;
397 	}
398 err_conf:
399 	return ret;
400 }
401 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);
402 
403 void pxa2xx_ac97_hw_remove(struct platform_device *dev)
404 {
405 	if (cpu_is_pxa27x())
406 		gpio_free(reset_gpio);
407 	GCR |= GCR_ACLINK_OFF;
408 	free_irq(IRQ_AC97, NULL);
409 	if (ac97conf_clk) {
410 		clk_put(ac97conf_clk);
411 		ac97conf_clk = NULL;
412 	}
413 	clk_disable(ac97_clk);
414 	clk_put(ac97_clk);
415 	ac97_clk = NULL;
416 }
417 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_remove);
418 
419 MODULE_AUTHOR("Nicolas Pitre");
420 MODULE_DESCRIPTION("Intel/Marvell PXA sound library");
421 MODULE_LICENSE("GPL");
422 
423