xref: /openbmc/linux/sound/arm/pxa2xx-ac97-lib.c (revision 9cfc5c90)
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;
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 }
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_configure_ac97reset(reset_gpio, true);
141 	udelay(10);
142 	GCR |= GCR_WARM_RST;
143 	pxa27x_configure_ac97reset(reset_gpio, false);
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_prepare_enable(ac97conf_clk);
156 	udelay(5);
157 	clk_disable_unprepare(ac97conf_clk);
158 	GCR = GCR_COLD_RST | GCR_WARM_RST;
159 }
160 #endif
161 
162 #ifdef CONFIG_PXA3xx
163 static inline void pxa_ac97_warm_pxa3xx(void)
164 {
165 	gsr_bits = 0;
166 
167 	/* Can't use interrupts */
168 	GCR |= GCR_WARM_RST;
169 }
170 
171 static inline void pxa_ac97_cold_pxa3xx(void)
172 {
173 	/* Hold CLKBPB for 100us */
174 	GCR = 0;
175 	GCR = GCR_CLKBPB;
176 	udelay(100);
177 	GCR = 0;
178 
179 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
180 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
181 
182 	gsr_bits = 0;
183 
184 	/* Can't use interrupts on PXA3xx */
185 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
186 
187 	GCR = GCR_WARM_RST | GCR_COLD_RST;
188 }
189 #endif
190 
191 bool pxa2xx_ac97_try_warm_reset(struct snd_ac97 *ac97)
192 {
193 	unsigned long gsr;
194 	unsigned int timeout = 100;
195 
196 #ifdef CONFIG_PXA25x
197 	if (cpu_is_pxa25x())
198 		pxa_ac97_warm_pxa25x();
199 	else
200 #endif
201 #ifdef CONFIG_PXA27x
202 	if (cpu_is_pxa27x())
203 		pxa_ac97_warm_pxa27x();
204 	else
205 #endif
206 #ifdef CONFIG_PXA3xx
207 	if (cpu_is_pxa3xx())
208 		pxa_ac97_warm_pxa3xx();
209 	else
210 #endif
211 		snd_BUG();
212 
213 	while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
214 		mdelay(1);
215 
216 	gsr = GSR | gsr_bits;
217 	if (!(gsr & (GSR_PCR | GSR_SCR))) {
218 		printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
219 				 __func__, gsr);
220 
221 		return false;
222 	}
223 
224 	return true;
225 }
226 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_warm_reset);
227 
228 bool pxa2xx_ac97_try_cold_reset(struct snd_ac97 *ac97)
229 {
230 	unsigned long gsr;
231 	unsigned int timeout = 1000;
232 
233 #ifdef CONFIG_PXA25x
234 	if (cpu_is_pxa25x())
235 		pxa_ac97_cold_pxa25x();
236 	else
237 #endif
238 #ifdef CONFIG_PXA27x
239 	if (cpu_is_pxa27x())
240 		pxa_ac97_cold_pxa27x();
241 	else
242 #endif
243 #ifdef CONFIG_PXA3xx
244 	if (cpu_is_pxa3xx())
245 		pxa_ac97_cold_pxa3xx();
246 	else
247 #endif
248 		snd_BUG();
249 
250 	while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
251 		mdelay(1);
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_unprepare(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_prepare_enable(ac97_clk);
310 	return 0;
311 }
312 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
313 #endif
314 
315 int 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 		/*
342 		 * This gpio is needed for a work-around to a bug in the ac97
343 		 * controller during warm reset.  The direction and level is set
344 		 * here so that it is an output driven high when switching from
345 		 * AC97_nRESET alt function to generic gpio.
346 		 */
347 		ret = gpio_request_one(reset_gpio, GPIOF_OUT_INIT_HIGH,
348 				       "pxa27x ac97 reset");
349 		if (ret < 0) {
350 			pr_err("%s: gpio_request_one() failed: %d\n",
351 			       __func__, ret);
352 			goto err_conf;
353 		}
354 		pxa27x_configure_ac97reset(reset_gpio, false);
355 
356 		ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
357 		if (IS_ERR(ac97conf_clk)) {
358 			ret = PTR_ERR(ac97conf_clk);
359 			ac97conf_clk = NULL;
360 			goto err_conf;
361 		}
362 	}
363 
364 	ac97_clk = clk_get(&dev->dev, "AC97CLK");
365 	if (IS_ERR(ac97_clk)) {
366 		ret = PTR_ERR(ac97_clk);
367 		ac97_clk = NULL;
368 		goto err_clk;
369 	}
370 
371 	ret = clk_prepare_enable(ac97_clk);
372 	if (ret)
373 		goto err_clk2;
374 
375 	ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, 0, "AC97", NULL);
376 	if (ret < 0)
377 		goto err_irq;
378 
379 	return 0;
380 
381 err_irq:
382 	GCR |= GCR_ACLINK_OFF;
383 err_clk2:
384 	clk_put(ac97_clk);
385 	ac97_clk = NULL;
386 err_clk:
387 	if (ac97conf_clk) {
388 		clk_put(ac97conf_clk);
389 		ac97conf_clk = NULL;
390 	}
391 err_conf:
392 	return ret;
393 }
394 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);
395 
396 void pxa2xx_ac97_hw_remove(struct platform_device *dev)
397 {
398 	if (cpu_is_pxa27x())
399 		gpio_free(reset_gpio);
400 	GCR |= GCR_ACLINK_OFF;
401 	free_irq(IRQ_AC97, NULL);
402 	if (ac97conf_clk) {
403 		clk_put(ac97conf_clk);
404 		ac97conf_clk = NULL;
405 	}
406 	clk_disable_unprepare(ac97_clk);
407 	clk_put(ac97_clk);
408 	ac97_clk = NULL;
409 }
410 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_remove);
411 
412 MODULE_AUTHOR("Nicolas Pitre");
413 MODULE_DESCRIPTION("Intel/Marvell PXA sound library");
414 MODULE_LICENSE("GPL");
415 
416