xref: /openbmc/linux/sound/arm/pxa2xx-ac97-lib.c (revision cfbb9be8)
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/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_configure_ac97reset(int reset_gpio, bool to_gpio);
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 int pxa2xx_ac97_read(int slot, unsigned short reg)
49 {
50 	int val = -ENODEV;
51 	volatile u32 *reg_addr;
52 
53 	if (slot > 0)
54 		return -ENODEV;
55 
56 	mutex_lock(&car_mutex);
57 
58 	/* set up primary or secondary codec space */
59 	if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
60 		reg_addr = slot ? &SMC_REG_BASE : &PMC_REG_BASE;
61 	else
62 		reg_addr = slot ? &SAC_REG_BASE : &PAC_REG_BASE;
63 	reg_addr += (reg >> 1);
64 
65 	/* start read access across the ac97 link */
66 	GSR = GSR_CDONE | GSR_SDONE;
67 	gsr_bits = 0;
68 	val = (*reg_addr & 0xffff);
69 	if (reg == AC97_GPIO_STATUS)
70 		goto out;
71 	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1) <= 0 &&
72 	    !((GSR | gsr_bits) & GSR_SDONE)) {
73 		printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n",
74 				__func__, reg, GSR | gsr_bits);
75 		val = -ETIMEDOUT;
76 		goto out;
77 	}
78 
79 	/* valid data now */
80 	GSR = GSR_CDONE | GSR_SDONE;
81 	gsr_bits = 0;
82 	val = (*reg_addr & 0xffff);
83 	/* but we've just started another cycle... */
84 	wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1);
85 
86 out:	mutex_unlock(&car_mutex);
87 	return val;
88 }
89 EXPORT_SYMBOL_GPL(pxa2xx_ac97_read);
90 
91 int pxa2xx_ac97_write(int slot, unsigned short reg, unsigned short val)
92 {
93 	volatile u32 *reg_addr;
94 	int ret = 0;
95 
96 	mutex_lock(&car_mutex);
97 
98 	/* set up primary or secondary codec space */
99 	if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
100 		reg_addr = slot ? &SMC_REG_BASE : &PMC_REG_BASE;
101 	else
102 		reg_addr = slot ? &SAC_REG_BASE : &PAC_REG_BASE;
103 	reg_addr += (reg >> 1);
104 
105 	GSR = GSR_CDONE | GSR_SDONE;
106 	gsr_bits = 0;
107 	*reg_addr = val;
108 	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_CDONE, 1) <= 0 &&
109 	    !((GSR | gsr_bits) & GSR_CDONE)) {
110 		printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n",
111 				__func__, reg, GSR | gsr_bits);
112 		ret = -EIO;
113 	}
114 
115 	mutex_unlock(&car_mutex);
116 	return ret;
117 }
118 EXPORT_SYMBOL_GPL(pxa2xx_ac97_write);
119 
120 #ifdef CONFIG_PXA25x
121 static inline void pxa_ac97_warm_pxa25x(void)
122 {
123 	gsr_bits = 0;
124 
125 	GCR |= GCR_WARM_RST;
126 }
127 
128 static inline void pxa_ac97_cold_pxa25x(void)
129 {
130 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
131 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
132 
133 	gsr_bits = 0;
134 
135 	GCR = GCR_COLD_RST;
136 }
137 #endif
138 
139 #ifdef CONFIG_PXA27x
140 static inline void pxa_ac97_warm_pxa27x(void)
141 {
142 	gsr_bits = 0;
143 
144 	/* warm reset broken on Bulverde, so manually keep AC97 reset high */
145 	pxa27x_configure_ac97reset(reset_gpio, true);
146 	udelay(10);
147 	GCR |= GCR_WARM_RST;
148 	pxa27x_configure_ac97reset(reset_gpio, false);
149 	udelay(500);
150 }
151 
152 static inline void pxa_ac97_cold_pxa27x(void)
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_prepare_enable(ac97conf_clk);
161 	udelay(5);
162 	clk_disable_unprepare(ac97conf_clk);
163 	GCR = GCR_COLD_RST | GCR_WARM_RST;
164 }
165 #endif
166 
167 #ifdef CONFIG_PXA3xx
168 static inline void pxa_ac97_warm_pxa3xx(void)
169 {
170 	gsr_bits = 0;
171 
172 	/* Can't use interrupts */
173 	GCR |= GCR_WARM_RST;
174 }
175 
176 static inline void pxa_ac97_cold_pxa3xx(void)
177 {
178 	/* Hold CLKBPB for 100us */
179 	GCR = 0;
180 	GCR = GCR_CLKBPB;
181 	udelay(100);
182 	GCR = 0;
183 
184 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
185 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */
186 
187 	gsr_bits = 0;
188 
189 	/* Can't use interrupts on PXA3xx */
190 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
191 
192 	GCR = GCR_WARM_RST | GCR_COLD_RST;
193 }
194 #endif
195 
196 bool pxa2xx_ac97_try_warm_reset(void)
197 {
198 	unsigned long gsr;
199 	unsigned int timeout = 100;
200 
201 #ifdef CONFIG_PXA25x
202 	if (cpu_is_pxa25x())
203 		pxa_ac97_warm_pxa25x();
204 	else
205 #endif
206 #ifdef CONFIG_PXA27x
207 	if (cpu_is_pxa27x())
208 		pxa_ac97_warm_pxa27x();
209 	else
210 #endif
211 #ifdef CONFIG_PXA3xx
212 	if (cpu_is_pxa3xx())
213 		pxa_ac97_warm_pxa3xx();
214 	else
215 #endif
216 		snd_BUG();
217 
218 	while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
219 		mdelay(1);
220 
221 	gsr = GSR | gsr_bits;
222 	if (!(gsr & (GSR_PCR | GSR_SCR))) {
223 		printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
224 				 __func__, gsr);
225 
226 		return false;
227 	}
228 
229 	return true;
230 }
231 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_warm_reset);
232 
233 bool pxa2xx_ac97_try_cold_reset(void)
234 {
235 	unsigned long gsr;
236 	unsigned int timeout = 1000;
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 		snd_BUG();
254 
255 	while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
256 		mdelay(1);
257 
258 	gsr = GSR | gsr_bits;
259 	if (!(gsr & (GSR_PCR | GSR_SCR))) {
260 		printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
261 				 __func__, gsr);
262 
263 		return false;
264 	}
265 
266 	return true;
267 }
268 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_cold_reset);
269 
270 
271 void pxa2xx_ac97_finish_reset(void)
272 {
273 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
274 	GCR |= GCR_SDONE_IE|GCR_CDONE_IE;
275 }
276 EXPORT_SYMBOL_GPL(pxa2xx_ac97_finish_reset);
277 
278 static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
279 {
280 	long status;
281 
282 	status = GSR;
283 	if (status) {
284 		GSR = status;
285 		gsr_bits |= status;
286 		wake_up(&gsr_wq);
287 
288 		/* Although we don't use those we still need to clear them
289 		   since they tend to spuriously trigger when MMC is used
290 		   (hardware bug? go figure)... */
291 		if (cpu_is_pxa27x()) {
292 			MISR = MISR_EOC;
293 			PISR = PISR_EOC;
294 			MCSR = MCSR_EOC;
295 		}
296 
297 		return IRQ_HANDLED;
298 	}
299 
300 	return IRQ_NONE;
301 }
302 
303 #ifdef CONFIG_PM
304 int pxa2xx_ac97_hw_suspend(void)
305 {
306 	GCR |= GCR_ACLINK_OFF;
307 	clk_disable_unprepare(ac97_clk);
308 	return 0;
309 }
310 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_suspend);
311 
312 int pxa2xx_ac97_hw_resume(void)
313 {
314 	clk_prepare_enable(ac97_clk);
315 	return 0;
316 }
317 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
318 #endif
319 
320 int pxa2xx_ac97_hw_probe(struct platform_device *dev)
321 {
322 	int ret;
323 	pxa2xx_audio_ops_t *pdata = dev->dev.platform_data;
324 
325 	if (pdata) {
326 		switch (pdata->reset_gpio) {
327 		case 95:
328 		case 113:
329 			reset_gpio = pdata->reset_gpio;
330 			break;
331 		case 0:
332 			reset_gpio = 113;
333 			break;
334 		case -1:
335 			break;
336 		default:
337 			dev_err(&dev->dev, "Invalid reset GPIO %d\n",
338 				pdata->reset_gpio);
339 		}
340 	} else {
341 		if (cpu_is_pxa27x())
342 			reset_gpio = 113;
343 	}
344 
345 	if (cpu_is_pxa27x()) {
346 		/*
347 		 * This gpio is needed for a work-around to a bug in the ac97
348 		 * controller during warm reset.  The direction and level is set
349 		 * here so that it is an output driven high when switching from
350 		 * AC97_nRESET alt function to generic gpio.
351 		 */
352 		ret = gpio_request_one(reset_gpio, GPIOF_OUT_INIT_HIGH,
353 				       "pxa27x ac97 reset");
354 		if (ret < 0) {
355 			pr_err("%s: gpio_request_one() failed: %d\n",
356 			       __func__, ret);
357 			goto err_conf;
358 		}
359 		pxa27x_configure_ac97reset(reset_gpio, false);
360 
361 		ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
362 		if (IS_ERR(ac97conf_clk)) {
363 			ret = PTR_ERR(ac97conf_clk);
364 			ac97conf_clk = NULL;
365 			goto err_conf;
366 		}
367 	}
368 
369 	ac97_clk = clk_get(&dev->dev, "AC97CLK");
370 	if (IS_ERR(ac97_clk)) {
371 		ret = PTR_ERR(ac97_clk);
372 		ac97_clk = NULL;
373 		goto err_clk;
374 	}
375 
376 	ret = clk_prepare_enable(ac97_clk);
377 	if (ret)
378 		goto err_clk2;
379 
380 	ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, 0, "AC97", NULL);
381 	if (ret < 0)
382 		goto err_irq;
383 
384 	return 0;
385 
386 err_irq:
387 	GCR |= GCR_ACLINK_OFF;
388 err_clk2:
389 	clk_put(ac97_clk);
390 	ac97_clk = NULL;
391 err_clk:
392 	if (ac97conf_clk) {
393 		clk_put(ac97conf_clk);
394 		ac97conf_clk = NULL;
395 	}
396 err_conf:
397 	return ret;
398 }
399 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);
400 
401 void pxa2xx_ac97_hw_remove(struct platform_device *dev)
402 {
403 	if (cpu_is_pxa27x())
404 		gpio_free(reset_gpio);
405 	GCR |= GCR_ACLINK_OFF;
406 	free_irq(IRQ_AC97, NULL);
407 	if (ac97conf_clk) {
408 		clk_put(ac97conf_clk);
409 		ac97conf_clk = NULL;
410 	}
411 	clk_disable_unprepare(ac97_clk);
412 	clk_put(ac97_clk);
413 	ac97_clk = NULL;
414 }
415 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_remove);
416 
417 MODULE_AUTHOR("Nicolas Pitre");
418 MODULE_DESCRIPTION("Intel/Marvell PXA sound library");
419 MODULE_LICENSE("GPL");
420 
421