nfs: new subdir Documentation/filesystems/nfs
[safe/jmp/linux-2.6] / drivers / mfd / wm831x-irq.c
1 /*
2  * wm831x-irq.c  --  Interrupt controller support for Wolfson WM831x PMICs
3  *
4  * Copyright 2009 Wolfson Microelectronics PLC.
5  *
6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7  *
8  *  This program is free software; you can redistribute  it and/or modify it
9  *  under  the terms of  the GNU General  Public License as published by the
10  *  Free Software Foundation;  either version 2 of the  License, or (at your
11  *  option) any later version.
12  *
13  */
14
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/i2c.h>
18 #include <linux/mfd/core.h>
19 #include <linux/interrupt.h>
20
21 #include <linux/mfd/wm831x/core.h>
22 #include <linux/mfd/wm831x/pdata.h>
23 #include <linux/mfd/wm831x/irq.h>
24
25 #include <linux/delay.h>
26
27 /*
28  * Since generic IRQs don't currently support interrupt controllers on
29  * interrupt driven buses we don't use genirq but instead provide an
30  * interface that looks very much like the standard ones.  This leads
31  * to some bodges, including storing interrupt handler information in
32  * the static irq_data table we use to look up the data for individual
33  * interrupts, but hopefully won't last too long.
34  */
35
36 struct wm831x_irq_data {
37         int primary;
38         int reg;
39         int mask;
40         irq_handler_t handler;
41         void *handler_data;
42 };
43
44 static struct wm831x_irq_data wm831x_irqs[] = {
45         [WM831X_IRQ_TEMP_THW] = {
46                 .primary = WM831X_TEMP_INT,
47                 .reg = 1,
48                 .mask = WM831X_TEMP_THW_EINT,
49         },
50         [WM831X_IRQ_GPIO_1] = {
51                 .primary = WM831X_GP_INT,
52                 .reg = 5,
53                 .mask = WM831X_GP1_EINT,
54         },
55         [WM831X_IRQ_GPIO_2] = {
56                 .primary = WM831X_GP_INT,
57                 .reg = 5,
58                 .mask = WM831X_GP2_EINT,
59         },
60         [WM831X_IRQ_GPIO_3] = {
61                 .primary = WM831X_GP_INT,
62                 .reg = 5,
63                 .mask = WM831X_GP3_EINT,
64         },
65         [WM831X_IRQ_GPIO_4] = {
66                 .primary = WM831X_GP_INT,
67                 .reg = 5,
68                 .mask = WM831X_GP4_EINT,
69         },
70         [WM831X_IRQ_GPIO_5] = {
71                 .primary = WM831X_GP_INT,
72                 .reg = 5,
73                 .mask = WM831X_GP5_EINT,
74         },
75         [WM831X_IRQ_GPIO_6] = {
76                 .primary = WM831X_GP_INT,
77                 .reg = 5,
78                 .mask = WM831X_GP6_EINT,
79         },
80         [WM831X_IRQ_GPIO_7] = {
81                 .primary = WM831X_GP_INT,
82                 .reg = 5,
83                 .mask = WM831X_GP7_EINT,
84         },
85         [WM831X_IRQ_GPIO_8] = {
86                 .primary = WM831X_GP_INT,
87                 .reg = 5,
88                 .mask = WM831X_GP8_EINT,
89         },
90         [WM831X_IRQ_GPIO_9] = {
91                 .primary = WM831X_GP_INT,
92                 .reg = 5,
93                 .mask = WM831X_GP9_EINT,
94         },
95         [WM831X_IRQ_GPIO_10] = {
96                 .primary = WM831X_GP_INT,
97                 .reg = 5,
98                 .mask = WM831X_GP10_EINT,
99         },
100         [WM831X_IRQ_GPIO_11] = {
101                 .primary = WM831X_GP_INT,
102                 .reg = 5,
103                 .mask = WM831X_GP11_EINT,
104         },
105         [WM831X_IRQ_GPIO_12] = {
106                 .primary = WM831X_GP_INT,
107                 .reg = 5,
108                 .mask = WM831X_GP12_EINT,
109         },
110         [WM831X_IRQ_GPIO_13] = {
111                 .primary = WM831X_GP_INT,
112                 .reg = 5,
113                 .mask = WM831X_GP13_EINT,
114         },
115         [WM831X_IRQ_GPIO_14] = {
116                 .primary = WM831X_GP_INT,
117                 .reg = 5,
118                 .mask = WM831X_GP14_EINT,
119         },
120         [WM831X_IRQ_GPIO_15] = {
121                 .primary = WM831X_GP_INT,
122                 .reg = 5,
123                 .mask = WM831X_GP15_EINT,
124         },
125         [WM831X_IRQ_GPIO_16] = {
126                 .primary = WM831X_GP_INT,
127                 .reg = 5,
128                 .mask = WM831X_GP16_EINT,
129         },
130         [WM831X_IRQ_ON] = {
131                 .primary = WM831X_ON_PIN_INT,
132                 .reg = 1,
133                 .mask = WM831X_ON_PIN_EINT,
134         },
135         [WM831X_IRQ_PPM_SYSLO] = {
136                 .primary = WM831X_PPM_INT,
137                 .reg = 1,
138                 .mask = WM831X_PPM_SYSLO_EINT,
139         },
140         [WM831X_IRQ_PPM_PWR_SRC] = {
141                 .primary = WM831X_PPM_INT,
142                 .reg = 1,
143                 .mask = WM831X_PPM_PWR_SRC_EINT,
144         },
145         [WM831X_IRQ_PPM_USB_CURR] = {
146                 .primary = WM831X_PPM_INT,
147                 .reg = 1,
148                 .mask = WM831X_PPM_USB_CURR_EINT,
149         },
150         [WM831X_IRQ_WDOG_TO] = {
151                 .primary = WM831X_WDOG_INT,
152                 .reg = 1,
153                 .mask = WM831X_WDOG_TO_EINT,
154         },
155         [WM831X_IRQ_RTC_PER] = {
156                 .primary = WM831X_RTC_INT,
157                 .reg = 1,
158                 .mask = WM831X_RTC_PER_EINT,
159         },
160         [WM831X_IRQ_RTC_ALM] = {
161                 .primary = WM831X_RTC_INT,
162                 .reg = 1,
163                 .mask = WM831X_RTC_ALM_EINT,
164         },
165         [WM831X_IRQ_CHG_BATT_HOT] = {
166                 .primary = WM831X_CHG_INT,
167                 .reg = 2,
168                 .mask = WM831X_CHG_BATT_HOT_EINT,
169         },
170         [WM831X_IRQ_CHG_BATT_COLD] = {
171                 .primary = WM831X_CHG_INT,
172                 .reg = 2,
173                 .mask = WM831X_CHG_BATT_COLD_EINT,
174         },
175         [WM831X_IRQ_CHG_BATT_FAIL] = {
176                 .primary = WM831X_CHG_INT,
177                 .reg = 2,
178                 .mask = WM831X_CHG_BATT_FAIL_EINT,
179         },
180         [WM831X_IRQ_CHG_OV] = {
181                 .primary = WM831X_CHG_INT,
182                 .reg = 2,
183                 .mask = WM831X_CHG_OV_EINT,
184         },
185         [WM831X_IRQ_CHG_END] = {
186                 .primary = WM831X_CHG_INT,
187                 .reg = 2,
188                 .mask = WM831X_CHG_END_EINT,
189         },
190         [WM831X_IRQ_CHG_TO] = {
191                 .primary = WM831X_CHG_INT,
192                 .reg = 2,
193                 .mask = WM831X_CHG_TO_EINT,
194         },
195         [WM831X_IRQ_CHG_MODE] = {
196                 .primary = WM831X_CHG_INT,
197                 .reg = 2,
198                 .mask = WM831X_CHG_MODE_EINT,
199         },
200         [WM831X_IRQ_CHG_START] = {
201                 .primary = WM831X_CHG_INT,
202                 .reg = 2,
203                 .mask = WM831X_CHG_START_EINT,
204         },
205         [WM831X_IRQ_TCHDATA] = {
206                 .primary = WM831X_TCHDATA_INT,
207                 .reg = 1,
208                 .mask = WM831X_TCHDATA_EINT,
209         },
210         [WM831X_IRQ_TCHPD] = {
211                 .primary = WM831X_TCHPD_INT,
212                 .reg = 1,
213                 .mask = WM831X_TCHPD_EINT,
214         },
215         [WM831X_IRQ_AUXADC_DATA] = {
216                 .primary = WM831X_AUXADC_INT,
217                 .reg = 1,
218                 .mask = WM831X_AUXADC_DATA_EINT,
219         },
220         [WM831X_IRQ_AUXADC_DCOMP1] = {
221                 .primary = WM831X_AUXADC_INT,
222                 .reg = 1,
223                 .mask = WM831X_AUXADC_DCOMP1_EINT,
224         },
225         [WM831X_IRQ_AUXADC_DCOMP2] = {
226                 .primary = WM831X_AUXADC_INT,
227                 .reg = 1,
228                 .mask = WM831X_AUXADC_DCOMP2_EINT,
229         },
230         [WM831X_IRQ_AUXADC_DCOMP3] = {
231                 .primary = WM831X_AUXADC_INT,
232                 .reg = 1,
233                 .mask = WM831X_AUXADC_DCOMP3_EINT,
234         },
235         [WM831X_IRQ_AUXADC_DCOMP4] = {
236                 .primary = WM831X_AUXADC_INT,
237                 .reg = 1,
238                 .mask = WM831X_AUXADC_DCOMP4_EINT,
239         },
240         [WM831X_IRQ_CS1] = {
241                 .primary = WM831X_CS_INT,
242                 .reg = 2,
243                 .mask = WM831X_CS1_EINT,
244         },
245         [WM831X_IRQ_CS2] = {
246                 .primary = WM831X_CS_INT,
247                 .reg = 2,
248                 .mask = WM831X_CS2_EINT,
249         },
250         [WM831X_IRQ_HC_DC1] = {
251                 .primary = WM831X_HC_INT,
252                 .reg = 4,
253                 .mask = WM831X_HC_DC1_EINT,
254         },
255         [WM831X_IRQ_HC_DC2] = {
256                 .primary = WM831X_HC_INT,
257                 .reg = 4,
258                 .mask = WM831X_HC_DC2_EINT,
259         },
260         [WM831X_IRQ_UV_LDO1] = {
261                 .primary = WM831X_UV_INT,
262                 .reg = 3,
263                 .mask = WM831X_UV_LDO1_EINT,
264         },
265         [WM831X_IRQ_UV_LDO2] = {
266                 .primary = WM831X_UV_INT,
267                 .reg = 3,
268                 .mask = WM831X_UV_LDO2_EINT,
269         },
270         [WM831X_IRQ_UV_LDO3] = {
271                 .primary = WM831X_UV_INT,
272                 .reg = 3,
273                 .mask = WM831X_UV_LDO3_EINT,
274         },
275         [WM831X_IRQ_UV_LDO4] = {
276                 .primary = WM831X_UV_INT,
277                 .reg = 3,
278                 .mask = WM831X_UV_LDO4_EINT,
279         },
280         [WM831X_IRQ_UV_LDO5] = {
281                 .primary = WM831X_UV_INT,
282                 .reg = 3,
283                 .mask = WM831X_UV_LDO5_EINT,
284         },
285         [WM831X_IRQ_UV_LDO6] = {
286                 .primary = WM831X_UV_INT,
287                 .reg = 3,
288                 .mask = WM831X_UV_LDO6_EINT,
289         },
290         [WM831X_IRQ_UV_LDO7] = {
291                 .primary = WM831X_UV_INT,
292                 .reg = 3,
293                 .mask = WM831X_UV_LDO7_EINT,
294         },
295         [WM831X_IRQ_UV_LDO8] = {
296                 .primary = WM831X_UV_INT,
297                 .reg = 3,
298                 .mask = WM831X_UV_LDO8_EINT,
299         },
300         [WM831X_IRQ_UV_LDO9] = {
301                 .primary = WM831X_UV_INT,
302                 .reg = 3,
303                 .mask = WM831X_UV_LDO9_EINT,
304         },
305         [WM831X_IRQ_UV_LDO10] = {
306                 .primary = WM831X_UV_INT,
307                 .reg = 3,
308                 .mask = WM831X_UV_LDO10_EINT,
309         },
310         [WM831X_IRQ_UV_DC1] = {
311                 .primary = WM831X_UV_INT,
312                 .reg = 4,
313                 .mask = WM831X_UV_DC1_EINT,
314         },
315         [WM831X_IRQ_UV_DC2] = {
316                 .primary = WM831X_UV_INT,
317                 .reg = 4,
318                 .mask = WM831X_UV_DC2_EINT,
319         },
320         [WM831X_IRQ_UV_DC3] = {
321                 .primary = WM831X_UV_INT,
322                 .reg = 4,
323                 .mask = WM831X_UV_DC3_EINT,
324         },
325         [WM831X_IRQ_UV_DC4] = {
326                 .primary = WM831X_UV_INT,
327                 .reg = 4,
328                 .mask = WM831X_UV_DC4_EINT,
329         },
330 };
331
332 static inline int irq_data_to_status_reg(struct wm831x_irq_data *irq_data)
333 {
334         return WM831X_INTERRUPT_STATUS_1 - 1 + irq_data->reg;
335 }
336
337 static inline int irq_data_to_mask_reg(struct wm831x_irq_data *irq_data)
338 {
339         return WM831X_INTERRUPT_STATUS_1_MASK - 1 + irq_data->reg;
340 }
341
342 static void __wm831x_enable_irq(struct wm831x *wm831x, int irq)
343 {
344         struct wm831x_irq_data *irq_data = &wm831x_irqs[irq];
345
346         wm831x->irq_masks[irq_data->reg - 1] &= ~irq_data->mask;
347         wm831x_reg_write(wm831x, irq_data_to_mask_reg(irq_data),
348                          wm831x->irq_masks[irq_data->reg - 1]);
349 }
350
351 void wm831x_enable_irq(struct wm831x *wm831x, int irq)
352 {
353         mutex_lock(&wm831x->irq_lock);
354         __wm831x_enable_irq(wm831x, irq);
355         mutex_unlock(&wm831x->irq_lock);
356 }
357 EXPORT_SYMBOL_GPL(wm831x_enable_irq);
358
359 static void __wm831x_disable_irq(struct wm831x *wm831x, int irq)
360 {
361         struct wm831x_irq_data *irq_data = &wm831x_irqs[irq];
362
363         wm831x->irq_masks[irq_data->reg - 1] |= irq_data->mask;
364         wm831x_reg_write(wm831x, irq_data_to_mask_reg(irq_data),
365                          wm831x->irq_masks[irq_data->reg - 1]);
366 }
367
368 void wm831x_disable_irq(struct wm831x *wm831x, int irq)
369 {
370         mutex_lock(&wm831x->irq_lock);
371         __wm831x_disable_irq(wm831x, irq);
372         mutex_unlock(&wm831x->irq_lock);
373 }
374 EXPORT_SYMBOL_GPL(wm831x_disable_irq);
375
376 int wm831x_request_irq(struct wm831x *wm831x,
377                        unsigned int irq, irq_handler_t handler,
378                        unsigned long flags, const char *name,
379                        void *dev)
380 {
381         int ret = 0;
382
383         if (irq < 0 || irq >= WM831X_NUM_IRQS)
384                 return -EINVAL;
385
386         mutex_lock(&wm831x->irq_lock);
387
388         if (wm831x_irqs[irq].handler) {
389                 dev_err(wm831x->dev, "Already have handler for IRQ %d\n", irq);
390                 ret = -EINVAL;
391                 goto out;
392         }
393
394         wm831x_irqs[irq].handler = handler;
395         wm831x_irqs[irq].handler_data = dev;
396
397         __wm831x_enable_irq(wm831x, irq);
398
399 out:
400         mutex_unlock(&wm831x->irq_lock);
401
402         return ret;
403 }
404 EXPORT_SYMBOL_GPL(wm831x_request_irq);
405
406 void wm831x_free_irq(struct wm831x *wm831x, unsigned int irq, void *data)
407 {
408         if (irq < 0 || irq >= WM831X_NUM_IRQS)
409                 return;
410
411         mutex_lock(&wm831x->irq_lock);
412
413         wm831x_irqs[irq].handler = NULL;
414         wm831x_irqs[irq].handler_data = NULL;
415
416         __wm831x_disable_irq(wm831x, irq);
417
418         mutex_unlock(&wm831x->irq_lock);
419 }
420 EXPORT_SYMBOL_GPL(wm831x_free_irq);
421
422
423 static void wm831x_handle_irq(struct wm831x *wm831x, int irq, int status)
424 {
425         struct wm831x_irq_data *irq_data = &wm831x_irqs[irq];
426
427         if (irq_data->handler) {
428                 irq_data->handler(irq, irq_data->handler_data);
429                 wm831x_reg_write(wm831x, irq_data_to_status_reg(irq_data),
430                                  irq_data->mask);
431         } else {
432                 dev_err(wm831x->dev, "Unhandled IRQ %d, masking\n", irq);
433                 __wm831x_disable_irq(wm831x, irq);
434         }
435 }
436
437 /* Main interrupt handling occurs in a workqueue since we need
438  * interrupts enabled to interact with the chip. */
439 static void wm831x_irq_worker(struct work_struct *work)
440 {
441         struct wm831x *wm831x = container_of(work, struct wm831x, irq_work);
442         unsigned int i;
443         int primary;
444         int status_regs[5];
445         int read[5] = { 0 };
446         int *status;
447
448         primary = wm831x_reg_read(wm831x, WM831X_SYSTEM_INTERRUPTS);
449         if (primary < 0) {
450                 dev_err(wm831x->dev, "Failed to read system interrupt: %d\n",
451                         primary);
452                 goto out;
453         }
454
455         mutex_lock(&wm831x->irq_lock);
456
457         for (i = 0; i < ARRAY_SIZE(wm831x_irqs); i++) {
458                 int offset = wm831x_irqs[i].reg - 1;
459
460                 if (!(primary & wm831x_irqs[i].primary))
461                         continue;
462
463                 status = &status_regs[offset];
464
465                 /* Hopefully there should only be one register to read
466                  * each time otherwise we ought to do a block read. */
467                 if (!read[offset]) {
468                         *status = wm831x_reg_read(wm831x,
469                                      irq_data_to_status_reg(&wm831x_irqs[i]));
470                         if (*status < 0) {
471                                 dev_err(wm831x->dev,
472                                         "Failed to read IRQ status: %d\n",
473                                         *status);
474                                 goto out_lock;
475                         }
476
477                         /* Mask out the disabled IRQs */
478                         *status &= ~wm831x->irq_masks[offset];
479                         read[offset] = 1;
480                 }
481
482                 if (*status & wm831x_irqs[i].mask)
483                         wm831x_handle_irq(wm831x, i, *status);
484         }
485
486 out_lock:
487         mutex_unlock(&wm831x->irq_lock);
488 out:
489         enable_irq(wm831x->irq);
490 }
491
492
493 static irqreturn_t wm831x_cpu_irq(int irq, void *data)
494 {
495         struct wm831x *wm831x = data;
496
497         /* Shut the interrupt to the CPU up and schedule the actual
498          * handler; we can't check that the IRQ is asserted. */
499         disable_irq_nosync(irq);
500
501         queue_work(wm831x->irq_wq, &wm831x->irq_work);
502
503         return IRQ_HANDLED;
504 }
505
506 int wm831x_irq_init(struct wm831x *wm831x, int irq)
507 {
508         int i, ret;
509
510         if (!irq) {
511                 dev_warn(wm831x->dev,
512                          "No interrupt specified - functionality limited\n");
513                 return 0;
514         }
515
516
517         wm831x->irq_wq = create_singlethread_workqueue("wm831x-irq");
518         if (!wm831x->irq_wq) {
519                 dev_err(wm831x->dev, "Failed to allocate IRQ worker\n");
520                 return -ESRCH;
521         }
522
523         wm831x->irq = irq;
524         mutex_init(&wm831x->irq_lock);
525         INIT_WORK(&wm831x->irq_work, wm831x_irq_worker);
526
527         /* Mask the individual interrupt sources */
528         for (i = 0; i < ARRAY_SIZE(wm831x->irq_masks); i++) {
529                 wm831x->irq_masks[i] = 0xffff;
530                 wm831x_reg_write(wm831x, WM831X_INTERRUPT_STATUS_1_MASK + i,
531                                  0xffff);
532         }
533
534         /* Enable top level interrupts, we mask at secondary level */
535         wm831x_reg_write(wm831x, WM831X_SYSTEM_INTERRUPTS_MASK, 0);
536
537         /* We're good to go.  We set IRQF_SHARED since there's a
538          * chance the driver will interoperate with another driver but
539          * the need to disable the IRQ while handing via I2C/SPI means
540          * that this may break and performance will be impacted.  If
541          * this does happen it's a hardware design issue and the only
542          * other alternative would be polling.
543          */
544         ret = request_irq(irq, wm831x_cpu_irq, IRQF_TRIGGER_LOW | IRQF_SHARED,
545                           "wm831x", wm831x);
546         if (ret != 0) {
547                 dev_err(wm831x->dev, "Failed to request IRQ %d: %d\n",
548                         irq, ret);
549                 return ret;
550         }
551
552         return 0;
553 }
554
555 void wm831x_irq_exit(struct wm831x *wm831x)
556 {
557         if (wm831x->irq)
558                 free_irq(wm831x->irq, wm831x);
559 }