xref: /openbmc/linux/drivers/mfd/wm831x-irq.c (revision fd589a8f)
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 }
560