libata: fix NULL sdev dereference race in atapi_qc_complete()
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / sound / arm / pxa2xx-ac97-lib.c
blob6fdca97186e769ae485f5b4bdf4332e69aa373f8
1 /*
2 * Based on sound/arm/pxa2xx-ac97.c and sound/soc/pxa/pxa2xx-ac97.c
3 * which contain:
5 * Author: Nicolas Pitre
6 * Created: Dec 02, 2004
7 * Copyright: MontaVista Software Inc.
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.
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>
20 #include <sound/ac97_codec.h>
21 #include <sound/pxa2xx-lib.h>
23 #include <asm/irq.h>
24 #include <mach/regs-ac97.h>
25 #include <mach/pxa2xx-gpio.h>
26 #include <mach/audio.h>
28 static DEFINE_MUTEX(car_mutex);
29 static DECLARE_WAIT_QUEUE_HEAD(gsr_wq);
30 static volatile long gsr_bits;
31 static struct clk *ac97_clk;
32 static struct clk *ac97conf_clk;
33 static int reset_gpio;
36 * Beware PXA27x bugs:
38 * o Slot 12 read from modem space will hang controller.
39 * o CDONE, SDONE interrupt fails after any slot 12 IO.
41 * We therefore have an hybrid approach for waiting on SDONE (interrupt or
42 * 1 jiffy timeout if interrupt never comes).
45 enum {
46 RESETGPIO_FORCE_HIGH,
47 RESETGPIO_FORCE_LOW,
48 RESETGPIO_NORMAL_ALTFUNC
51 /**
52 * set_resetgpio_mode - computes and sets the AC97_RESET gpio mode on PXA
53 * @mode: chosen action
55 * As the PXA27x CPUs suffer from a AC97 bug, a manual control of the reset line
56 * must be done to insure proper work of AC97 reset line. This function
57 * computes the correct gpio_mode for further use by reset functions, and
58 * applied the change through pxa_gpio_mode.
60 static void set_resetgpio_mode(int resetgpio_action)
62 int mode = 0;
64 if (reset_gpio)
65 switch (resetgpio_action) {
66 case RESETGPIO_NORMAL_ALTFUNC:
67 if (reset_gpio == 113)
68 mode = 113 | GPIO_ALT_FN_2_OUT;
69 if (reset_gpio == 95)
70 mode = 95 | GPIO_ALT_FN_1_OUT;
71 break;
72 case RESETGPIO_FORCE_LOW:
73 mode = reset_gpio | GPIO_OUT | GPIO_DFLT_LOW;
74 break;
75 case RESETGPIO_FORCE_HIGH:
76 mode = reset_gpio | GPIO_OUT | GPIO_DFLT_HIGH;
77 break;
80 if (mode)
81 pxa_gpio_mode(mode);
84 unsigned short pxa2xx_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
86 unsigned short val = -1;
87 volatile u32 *reg_addr;
89 mutex_lock(&car_mutex);
91 /* set up primary or secondary codec space */
92 if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
93 reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
94 else
95 reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
96 reg_addr += (reg >> 1);
98 /* start read access across the ac97 link */
99 GSR = GSR_CDONE | GSR_SDONE;
100 gsr_bits = 0;
101 val = *reg_addr;
102 if (reg == AC97_GPIO_STATUS)
103 goto out;
104 if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1) <= 0 &&
105 !((GSR | gsr_bits) & GSR_SDONE)) {
106 printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n",
107 __func__, reg, GSR | gsr_bits);
108 val = -1;
109 goto out;
112 /* valid data now */
113 GSR = GSR_CDONE | GSR_SDONE;
114 gsr_bits = 0;
115 val = *reg_addr;
116 /* but we've just started another cycle... */
117 wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1);
119 out: mutex_unlock(&car_mutex);
120 return val;
122 EXPORT_SYMBOL_GPL(pxa2xx_ac97_read);
124 void pxa2xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
125 unsigned short val)
127 volatile u32 *reg_addr;
129 mutex_lock(&car_mutex);
131 /* set up primary or secondary codec space */
132 if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
133 reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
134 else
135 reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
136 reg_addr += (reg >> 1);
138 GSR = GSR_CDONE | GSR_SDONE;
139 gsr_bits = 0;
140 *reg_addr = val;
141 if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_CDONE, 1) <= 0 &&
142 !((GSR | gsr_bits) & GSR_CDONE))
143 printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n",
144 __func__, reg, GSR | gsr_bits);
146 mutex_unlock(&car_mutex);
148 EXPORT_SYMBOL_GPL(pxa2xx_ac97_write);
150 #ifdef CONFIG_PXA25x
151 static inline void pxa_ac97_warm_pxa25x(void)
153 gsr_bits = 0;
155 GCR |= GCR_WARM_RST | GCR_PRIRDY_IEN | GCR_SECRDY_IEN;
156 wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
159 static inline void pxa_ac97_cold_pxa25x(void)
161 GCR &= GCR_COLD_RST; /* clear everything but nCRST */
162 GCR &= ~GCR_COLD_RST; /* then assert nCRST */
164 gsr_bits = 0;
166 GCR = GCR_COLD_RST;
167 GCR |= GCR_CDONE_IE|GCR_SDONE_IE;
168 wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
170 #endif
172 #ifdef CONFIG_PXA27x
173 static inline void pxa_ac97_warm_pxa27x(void)
175 gsr_bits = 0;
177 /* warm reset broken on Bulverde,
178 so manually keep AC97 reset high */
179 set_resetgpio_mode(RESETGPIO_FORCE_HIGH);
180 udelay(10);
181 GCR |= GCR_WARM_RST;
182 set_resetgpio_mode(RESETGPIO_NORMAL_ALTFUNC);
183 udelay(500);
186 static inline void pxa_ac97_cold_pxa27x(void)
188 GCR &= GCR_COLD_RST; /* clear everything but nCRST */
189 GCR &= ~GCR_COLD_RST; /* then assert nCRST */
191 gsr_bits = 0;
193 /* PXA27x Developers Manual section 13.5.2.2.1 */
194 clk_enable(ac97conf_clk);
195 udelay(5);
196 clk_disable(ac97conf_clk);
197 GCR = GCR_COLD_RST;
198 udelay(50);
200 #endif
202 #ifdef CONFIG_PXA3xx
203 static inline void pxa_ac97_warm_pxa3xx(void)
205 int timeout = 100;
207 gsr_bits = 0;
209 /* Can't use interrupts */
210 GCR |= GCR_WARM_RST;
211 while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
212 mdelay(1);
215 static inline void pxa_ac97_cold_pxa3xx(void)
217 int timeout = 1000;
219 /* Hold CLKBPB for 100us */
220 GCR = 0;
221 GCR = GCR_CLKBPB;
222 udelay(100);
223 GCR = 0;
225 GCR &= GCR_COLD_RST; /* clear everything but nCRST */
226 GCR &= ~GCR_COLD_RST; /* then assert nCRST */
228 gsr_bits = 0;
230 /* Can't use interrupts on PXA3xx */
231 GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
233 GCR = GCR_WARM_RST | GCR_COLD_RST;
234 while (!(GSR & (GSR_PCR | GSR_SCR)) && timeout--)
235 mdelay(10);
237 #endif
239 bool pxa2xx_ac97_try_warm_reset(struct snd_ac97 *ac97)
241 unsigned long gsr;
243 #ifdef CONFIG_PXA25x
244 if (cpu_is_pxa25x())
245 pxa_ac97_warm_pxa25x();
246 else
247 #endif
248 #ifdef CONFIG_PXA27x
249 if (cpu_is_pxa27x())
250 pxa_ac97_warm_pxa27x();
251 else
252 #endif
253 #ifdef CONFIG_PXA3xx
254 if (cpu_is_pxa3xx())
255 pxa_ac97_warm_pxa3xx();
256 else
257 #endif
258 BUG();
259 gsr = GSR | gsr_bits;
260 if (!(gsr & (GSR_PCR | GSR_SCR))) {
261 printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
262 __func__, gsr);
264 return false;
267 return true;
269 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_warm_reset);
271 bool pxa2xx_ac97_try_cold_reset(struct snd_ac97 *ac97)
273 unsigned long gsr;
275 #ifdef CONFIG_PXA25x
276 if (cpu_is_pxa25x())
277 pxa_ac97_cold_pxa25x();
278 else
279 #endif
280 #ifdef CONFIG_PXA27x
281 if (cpu_is_pxa27x())
282 pxa_ac97_cold_pxa27x();
283 else
284 #endif
285 #ifdef CONFIG_PXA3xx
286 if (cpu_is_pxa3xx())
287 pxa_ac97_cold_pxa3xx();
288 else
289 #endif
290 BUG();
292 gsr = GSR | gsr_bits;
293 if (!(gsr & (GSR_PCR | GSR_SCR))) {
294 printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
295 __func__, gsr);
297 return false;
300 return true;
302 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_cold_reset);
305 void pxa2xx_ac97_finish_reset(struct snd_ac97 *ac97)
307 GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
308 GCR |= GCR_SDONE_IE|GCR_CDONE_IE;
310 EXPORT_SYMBOL_GPL(pxa2xx_ac97_finish_reset);
312 static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
314 long status;
316 status = GSR;
317 if (status) {
318 GSR = status;
319 gsr_bits |= status;
320 wake_up(&gsr_wq);
322 /* Although we don't use those we still need to clear them
323 since they tend to spuriously trigger when MMC is used
324 (hardware bug? go figure)... */
325 if (cpu_is_pxa27x()) {
326 MISR = MISR_EOC;
327 PISR = PISR_EOC;
328 MCSR = MCSR_EOC;
331 return IRQ_HANDLED;
334 return IRQ_NONE;
337 #ifdef CONFIG_PM
338 int pxa2xx_ac97_hw_suspend(void)
340 GCR |= GCR_ACLINK_OFF;
341 clk_disable(ac97_clk);
342 return 0;
344 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_suspend);
346 int pxa2xx_ac97_hw_resume(void)
348 if (cpu_is_pxa25x() || cpu_is_pxa27x()) {
349 pxa_gpio_mode(GPIO31_SYNC_AC97_MD);
350 pxa_gpio_mode(GPIO30_SDATA_OUT_AC97_MD);
351 pxa_gpio_mode(GPIO28_BITCLK_AC97_MD);
352 pxa_gpio_mode(GPIO29_SDATA_IN_AC97_MD);
354 if (cpu_is_pxa27x()) {
355 /* Use GPIO 113 or 95 as AC97 Reset on Bulverde */
356 set_resetgpio_mode(RESETGPIO_NORMAL_ALTFUNC);
358 clk_enable(ac97_clk);
359 return 0;
361 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
362 #endif
364 int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev)
366 int ret;
367 pxa2xx_audio_ops_t *pdata = dev->dev.platform_data;
369 if (pdata) {
370 switch (pdata->reset_gpio) {
371 case 95:
372 case 113:
373 reset_gpio = pdata->reset_gpio;
374 break;
375 case 0:
376 reset_gpio = 113;
377 break;
378 case -1:
379 break;
380 default:
381 dev_err(&dev->dev, "Invalid reset GPIO %d\n",
382 pdata->reset_gpio);
384 } else {
385 if (cpu_is_pxa27x())
386 reset_gpio = 113;
389 if (cpu_is_pxa25x() || cpu_is_pxa27x()) {
390 pxa_gpio_mode(GPIO31_SYNC_AC97_MD);
391 pxa_gpio_mode(GPIO30_SDATA_OUT_AC97_MD);
392 pxa_gpio_mode(GPIO28_BITCLK_AC97_MD);
393 pxa_gpio_mode(GPIO29_SDATA_IN_AC97_MD);
396 if (cpu_is_pxa27x()) {
397 /* Use GPIO 113 as AC97 Reset on Bulverde */
398 set_resetgpio_mode(RESETGPIO_NORMAL_ALTFUNC);
399 ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
400 if (IS_ERR(ac97conf_clk)) {
401 ret = PTR_ERR(ac97conf_clk);
402 ac97conf_clk = NULL;
403 goto err_conf;
407 ac97_clk = clk_get(&dev->dev, "AC97CLK");
408 if (IS_ERR(ac97_clk)) {
409 ret = PTR_ERR(ac97_clk);
410 ac97_clk = NULL;
411 goto err_clk;
414 ret = clk_enable(ac97_clk);
415 if (ret)
416 goto err_clk2;
418 ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, IRQF_DISABLED, "AC97", NULL);
419 if (ret < 0)
420 goto err_irq;
422 return 0;
424 err_irq:
425 GCR |= GCR_ACLINK_OFF;
426 err_clk2:
427 clk_put(ac97_clk);
428 ac97_clk = NULL;
429 err_clk:
430 if (ac97conf_clk) {
431 clk_put(ac97conf_clk);
432 ac97conf_clk = NULL;
434 err_conf:
435 return ret;
437 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);
439 void pxa2xx_ac97_hw_remove(struct platform_device *dev)
441 GCR |= GCR_ACLINK_OFF;
442 free_irq(IRQ_AC97, NULL);
443 if (ac97conf_clk) {
444 clk_put(ac97conf_clk);
445 ac97conf_clk = NULL;
447 clk_disable(ac97_clk);
448 clk_put(ac97_clk);
449 ac97_clk = NULL;
451 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_remove);
453 MODULE_AUTHOR("Nicolas Pitre");
454 MODULE_DESCRIPTION("Intel/Marvell PXA sound library");
455 MODULE_LICENSE("GPL");