xref: /linux/drivers/mfd/twl4030-irq.c (revision 10ce3cc919f50c2043b41ca968b43c26a3672600)
1 /*
2  * twl4030-irq.c - TWL4030/TPS659x0 irq support
3  *
4  * Copyright (C) 2005-2006 Texas Instruments, Inc.
5  *
6  * Modifications to defer interrupt handling to a kernel thread:
7  * Copyright (C) 2006 MontaVista Software, Inc.
8  *
9  * Based on tlv320aic23.c:
10  * Copyright (c) by Kai Svahn <kai.svahn@nokia.com>
11  *
12  * Code cleanup and modifications to IRQ handler.
13  * by syed khasim <x0khasim@ti.com>
14  *
15  * This program is free software; you can redistribute it and/or modify
16  * it under the terms of the GNU General Public License as published by
17  * the Free Software Foundation; either version 2 of the License, or
18  * (at your option) any later version.
19  *
20  * This program is distributed in the hope that it will be useful,
21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
23  * GNU General Public License for more details.
24  *
25  * You should have received a copy of the GNU General Public License
26  * along with this program; if not, write to the Free Software
27  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
28  */
29 
30 #include <linux/init.h>
31 #include <linux/interrupt.h>
32 #include <linux/irq.h>
33 #include <linux/slab.h>
34 
35 #include <linux/i2c/twl.h>
36 
37 #include "twl-core.h"
38 
39 /*
40  * TWL4030 IRQ handling has two stages in hardware, and thus in software.
41  * The Primary Interrupt Handler (PIH) stage exposes status bits saying
42  * which Secondary Interrupt Handler (SIH) stage is raising an interrupt.
43  * SIH modules are more traditional IRQ components, which support per-IRQ
44  * enable/disable and trigger controls; they do most of the work.
45  *
46  * These chips are designed to support IRQ handling from two different
47  * I2C masters.  Each has a dedicated IRQ line, and dedicated IRQ status
48  * and mask registers in the PIH and SIH modules.
49  *
50  * We set up IRQs starting at a platform-specified base, always starting
51  * with PIH and the SIH for PWR_INT and then usually adding GPIO:
52  *	base + 0  .. base + 7	PIH
53  *	base + 8  .. base + 15	SIH for PWR_INT
54  *	base + 16 .. base + 33	SIH for GPIO
55  */
56 
57 /* PIH register offsets */
58 #define REG_PIH_ISR_P1			0x01
59 #define REG_PIH_ISR_P2			0x02
60 #define REG_PIH_SIR			0x03	/* for testing */
61 
62 
63 /* Linux could (eventually) use either IRQ line */
64 static int irq_line;
65 
66 struct sih {
67 	char	name[8];
68 	u8	module;			/* module id */
69 	u8	control_offset;		/* for SIH_CTRL */
70 	bool	set_cor;
71 
72 	u8	bits;			/* valid in isr/imr */
73 	u8	bytes_ixr;		/* bytelen of ISR/IMR/SIR */
74 
75 	u8	edr_offset;
76 	u8	bytes_edr;		/* bytelen of EDR */
77 
78 	u8	irq_lines;		/* number of supported irq lines */
79 
80 	/* SIR ignored -- set interrupt, for testing only */
81 	struct sih_irq_data {
82 		u8	isr_offset;
83 		u8	imr_offset;
84 	} mask[2];
85 	/* + 2 bytes padding */
86 };
87 
88 static const struct sih *sih_modules;
89 static int nr_sih_modules;
90 
91 #define SIH_INITIALIZER(modname, nbits) \
92 	.module		= TWL4030_MODULE_ ## modname, \
93 	.control_offset = TWL4030_ ## modname ## _SIH_CTRL, \
94 	.bits		= nbits, \
95 	.bytes_ixr	= DIV_ROUND_UP(nbits, 8), \
96 	.edr_offset	= TWL4030_ ## modname ## _EDR, \
97 	.bytes_edr	= DIV_ROUND_UP((2*(nbits)), 8), \
98 	.irq_lines	= 2, \
99 	.mask = { { \
100 		.isr_offset	= TWL4030_ ## modname ## _ISR1, \
101 		.imr_offset	= TWL4030_ ## modname ## _IMR1, \
102 	}, \
103 	{ \
104 		.isr_offset	= TWL4030_ ## modname ## _ISR2, \
105 		.imr_offset	= TWL4030_ ## modname ## _IMR2, \
106 	}, },
107 
108 /* register naming policies are inconsistent ... */
109 #define TWL4030_INT_PWR_EDR		TWL4030_INT_PWR_EDR1
110 #define TWL4030_MODULE_KEYPAD_KEYP	TWL4030_MODULE_KEYPAD
111 #define TWL4030_MODULE_INT_PWR		TWL4030_MODULE_INT
112 
113 
114 /* Order in this table matches order in PIH_ISR.  That is,
115  * BIT(n) in PIH_ISR is sih_modules[n].
116  */
117 /* sih_modules_twl4030 is used both in twl4030 and twl5030 */
118 static const struct sih sih_modules_twl4030[6] = {
119 	[0] = {
120 		.name		= "gpio",
121 		.module		= TWL4030_MODULE_GPIO,
122 		.control_offset	= REG_GPIO_SIH_CTRL,
123 		.set_cor	= true,
124 		.bits		= TWL4030_GPIO_MAX,
125 		.bytes_ixr	= 3,
126 		/* Note: *all* of these IRQs default to no-trigger */
127 		.edr_offset	= REG_GPIO_EDR1,
128 		.bytes_edr	= 5,
129 		.irq_lines	= 2,
130 		.mask = { {
131 			.isr_offset	= REG_GPIO_ISR1A,
132 			.imr_offset	= REG_GPIO_IMR1A,
133 		}, {
134 			.isr_offset	= REG_GPIO_ISR1B,
135 			.imr_offset	= REG_GPIO_IMR1B,
136 		}, },
137 	},
138 	[1] = {
139 		.name		= "keypad",
140 		.set_cor	= true,
141 		SIH_INITIALIZER(KEYPAD_KEYP, 4)
142 	},
143 	[2] = {
144 		.name		= "bci",
145 		.module		= TWL4030_MODULE_INTERRUPTS,
146 		.control_offset	= TWL4030_INTERRUPTS_BCISIHCTRL,
147 		.set_cor	= true,
148 		.bits		= 12,
149 		.bytes_ixr	= 2,
150 		.edr_offset	= TWL4030_INTERRUPTS_BCIEDR1,
151 		/* Note: most of these IRQs default to no-trigger */
152 		.bytes_edr	= 3,
153 		.irq_lines	= 2,
154 		.mask = { {
155 			.isr_offset	= TWL4030_INTERRUPTS_BCIISR1A,
156 			.imr_offset	= TWL4030_INTERRUPTS_BCIIMR1A,
157 		}, {
158 			.isr_offset	= TWL4030_INTERRUPTS_BCIISR1B,
159 			.imr_offset	= TWL4030_INTERRUPTS_BCIIMR1B,
160 		}, },
161 	},
162 	[3] = {
163 		.name		= "madc",
164 		SIH_INITIALIZER(MADC, 4)
165 	},
166 	[4] = {
167 		/* USB doesn't use the same SIH organization */
168 		.name		= "usb",
169 	},
170 	[5] = {
171 		.name		= "power",
172 		.set_cor	= true,
173 		SIH_INITIALIZER(INT_PWR, 8)
174 	},
175 		/* there are no SIH modules #6 or #7 ... */
176 };
177 
178 static const struct sih sih_modules_twl5031[8] = {
179 	[0] = {
180 		.name		= "gpio",
181 		.module		= TWL4030_MODULE_GPIO,
182 		.control_offset	= REG_GPIO_SIH_CTRL,
183 		.set_cor	= true,
184 		.bits		= TWL4030_GPIO_MAX,
185 		.bytes_ixr	= 3,
186 		/* Note: *all* of these IRQs default to no-trigger */
187 		.edr_offset	= REG_GPIO_EDR1,
188 		.bytes_edr	= 5,
189 		.irq_lines	= 2,
190 		.mask = { {
191 			.isr_offset	= REG_GPIO_ISR1A,
192 			.imr_offset	= REG_GPIO_IMR1A,
193 		}, {
194 			.isr_offset	= REG_GPIO_ISR1B,
195 			.imr_offset	= REG_GPIO_IMR1B,
196 		}, },
197 	},
198 	[1] = {
199 		.name		= "keypad",
200 		.set_cor	= true,
201 		SIH_INITIALIZER(KEYPAD_KEYP, 4)
202 	},
203 	[2] = {
204 		.name		= "bci",
205 		.module		= TWL5031_MODULE_INTERRUPTS,
206 		.control_offset	= TWL5031_INTERRUPTS_BCISIHCTRL,
207 		.bits		= 7,
208 		.bytes_ixr	= 1,
209 		.edr_offset	= TWL5031_INTERRUPTS_BCIEDR1,
210 		/* Note: most of these IRQs default to no-trigger */
211 		.bytes_edr	= 2,
212 		.irq_lines	= 2,
213 		.mask = { {
214 			.isr_offset	= TWL5031_INTERRUPTS_BCIISR1,
215 			.imr_offset	= TWL5031_INTERRUPTS_BCIIMR1,
216 		}, {
217 			.isr_offset	= TWL5031_INTERRUPTS_BCIISR2,
218 			.imr_offset	= TWL5031_INTERRUPTS_BCIIMR2,
219 		}, },
220 	},
221 	[3] = {
222 		.name		= "madc",
223 		SIH_INITIALIZER(MADC, 4)
224 	},
225 	[4] = {
226 		/* USB doesn't use the same SIH organization */
227 		.name		= "usb",
228 	},
229 	[5] = {
230 		.name		= "power",
231 		.set_cor	= true,
232 		SIH_INITIALIZER(INT_PWR, 8)
233 	},
234 	[6] = {
235 		/*
236 		 * ECI/DBI doesn't use the same SIH organization.
237 		 * For example, it supports only one interrupt output line.
238 		 * That is, the interrupts are seen on both INT1 and INT2 lines.
239 		 */
240 		.name		= "eci_dbi",
241 		.module		= TWL5031_MODULE_ACCESSORY,
242 		.bits		= 9,
243 		.bytes_ixr	= 2,
244 		.irq_lines	= 1,
245 		.mask = { {
246 			.isr_offset	= TWL5031_ACIIDR_LSB,
247 			.imr_offset	= TWL5031_ACIIMR_LSB,
248 		}, },
249 
250 	},
251 	[7] = {
252 		/* Audio accessory */
253 		.name		= "audio",
254 		.module		= TWL5031_MODULE_ACCESSORY,
255 		.control_offset	= TWL5031_ACCSIHCTRL,
256 		.bits		= 2,
257 		.bytes_ixr	= 1,
258 		.edr_offset	= TWL5031_ACCEDR1,
259 		/* Note: most of these IRQs default to no-trigger */
260 		.bytes_edr	= 1,
261 		.irq_lines	= 2,
262 		.mask = { {
263 			.isr_offset	= TWL5031_ACCISR1,
264 			.imr_offset	= TWL5031_ACCIMR1,
265 		}, {
266 			.isr_offset	= TWL5031_ACCISR2,
267 			.imr_offset	= TWL5031_ACCIMR2,
268 		}, },
269 	},
270 };
271 
272 #undef TWL4030_MODULE_KEYPAD_KEYP
273 #undef TWL4030_MODULE_INT_PWR
274 #undef TWL4030_INT_PWR_EDR
275 
276 /*----------------------------------------------------------------------*/
277 
278 static unsigned twl4030_irq_base;
279 
280 /*
281  * handle_twl4030_pih() is the desc->handle method for the twl4030 interrupt.
282  * This is a chained interrupt, so there is no desc->action method for it.
283  * Now we need to query the interrupt controller in the twl4030 to determine
284  * which module is generating the interrupt request.  However, we can't do i2c
285  * transactions in interrupt context, so we must defer that work to a kernel
286  * thread.  All we do here is acknowledge and mask the interrupt and wakeup
287  * the kernel thread.
288  */
289 static irqreturn_t handle_twl4030_pih(int irq, void *devid)
290 {
291 	int		module_irq;
292 	irqreturn_t	ret;
293 	u8		pih_isr;
294 
295 	ret = twl_i2c_read_u8(TWL4030_MODULE_PIH, &pih_isr,
296 			REG_PIH_ISR_P1);
297 	if (ret) {
298 		pr_warning("twl4030: I2C error %d reading PIH ISR\n", ret);
299 		return IRQ_NONE;
300 	}
301 
302 	/* these handlers deal with the relevant SIH irq status */
303 	for (module_irq = twl4030_irq_base;
304 			pih_isr;
305 			pih_isr >>= 1, module_irq++) {
306 		if (pih_isr & 0x1)
307 			handle_nested_irq(module_irq);
308 	}
309 
310 	return IRQ_HANDLED;
311 }
312 /*----------------------------------------------------------------------*/
313 
314 /*
315  * twl4030_init_sih_modules() ... start from a known state where no
316  * IRQs will be coming in, and where we can quickly enable them then
317  * handle them as they arrive.  Mask all IRQs: maybe init SIH_CTRL.
318  *
319  * NOTE:  we don't touch EDR registers here; they stay with hardware
320  * defaults or whatever the last value was.  Note that when both EDR
321  * bits for an IRQ are clear, that's as if its IMR bit is set...
322  */
323 static int twl4030_init_sih_modules(unsigned line)
324 {
325 	const struct sih *sih;
326 	u8 buf[4];
327 	int i;
328 	int status;
329 
330 	/* line 0 == int1_n signal; line 1 == int2_n signal */
331 	if (line > 1)
332 		return -EINVAL;
333 
334 	irq_line = line;
335 
336 	/* disable all interrupts on our line */
337 	memset(buf, 0xff, sizeof buf);
338 	sih = sih_modules;
339 	for (i = 0; i < nr_sih_modules; i++, sih++) {
340 
341 		/* skip USB -- it's funky */
342 		if (!sih->bytes_ixr)
343 			continue;
344 
345 		/* Not all the SIH modules support multiple interrupt lines */
346 		if (sih->irq_lines <= line)
347 			continue;
348 
349 		status = twl_i2c_write(sih->module, buf,
350 				sih->mask[line].imr_offset, sih->bytes_ixr);
351 		if (status < 0)
352 			pr_err("twl4030: err %d initializing %s %s\n",
353 					status, sih->name, "IMR");
354 
355 		/* Maybe disable "exclusive" mode; buffer second pending irq;
356 		 * set Clear-On-Read (COR) bit.
357 		 *
358 		 * NOTE that sometimes COR polarity is documented as being
359 		 * inverted:  for MADC, COR=1 means "clear on write".
360 		 * And for PWR_INT it's not documented...
361 		 */
362 		if (sih->set_cor) {
363 			status = twl_i2c_write_u8(sih->module,
364 					TWL4030_SIH_CTRL_COR_MASK,
365 					sih->control_offset);
366 			if (status < 0)
367 				pr_err("twl4030: err %d initializing %s %s\n",
368 						status, sih->name, "SIH_CTRL");
369 		}
370 	}
371 
372 	sih = sih_modules;
373 	for (i = 0; i < nr_sih_modules; i++, sih++) {
374 		u8 rxbuf[4];
375 		int j;
376 
377 		/* skip USB */
378 		if (!sih->bytes_ixr)
379 			continue;
380 
381 		/* Not all the SIH modules support multiple interrupt lines */
382 		if (sih->irq_lines <= line)
383 			continue;
384 
385 		/* Clear pending interrupt status.  Either the read was
386 		 * enough, or we need to write those bits.  Repeat, in
387 		 * case an IRQ is pending (PENDDIS=0) ... that's not
388 		 * uncommon with PWR_INT.PWRON.
389 		 */
390 		for (j = 0; j < 2; j++) {
391 			status = twl_i2c_read(sih->module, rxbuf,
392 				sih->mask[line].isr_offset, sih->bytes_ixr);
393 			if (status < 0)
394 				pr_err("twl4030: err %d initializing %s %s\n",
395 					status, sih->name, "ISR");
396 
397 			if (!sih->set_cor)
398 				status = twl_i2c_write(sih->module, buf,
399 					sih->mask[line].isr_offset,
400 					sih->bytes_ixr);
401 			/* else COR=1 means read sufficed.
402 			 * (for most SIH modules...)
403 			 */
404 		}
405 	}
406 
407 	return 0;
408 }
409 
410 static inline void activate_irq(int irq)
411 {
412 #ifdef CONFIG_ARM
413 	/* ARM requires an extra step to clear IRQ_NOREQUEST, which it
414 	 * sets on behalf of every irq_chip.  Also sets IRQ_NOPROBE.
415 	 */
416 	set_irq_flags(irq, IRQF_VALID);
417 #else
418 	/* same effect on other architectures */
419 	irq_set_noprobe(irq);
420 #endif
421 }
422 
423 /*----------------------------------------------------------------------*/
424 
425 struct sih_agent {
426 	int			irq_base;
427 	const struct sih	*sih;
428 
429 	u32			imr;
430 	bool			imr_change_pending;
431 
432 	u32			edge_change;
433 
434 	struct mutex		irq_lock;
435 	char			*irq_name;
436 };
437 
438 /*----------------------------------------------------------------------*/
439 
440 /*
441  * All irq_chip methods get issued from code holding irq_desc[irq].lock,
442  * which can't perform the underlying I2C operations (because they sleep).
443  * So we must hand them off to a thread (workqueue) and cope with asynch
444  * completion, potentially including some re-ordering, of these requests.
445  */
446 
447 static void twl4030_sih_mask(struct irq_data *data)
448 {
449 	struct sih_agent *agent = irq_data_get_irq_chip_data(data);
450 
451 	agent->imr |= BIT(data->irq - agent->irq_base);
452 	agent->imr_change_pending = true;
453 }
454 
455 static void twl4030_sih_unmask(struct irq_data *data)
456 {
457 	struct sih_agent *agent = irq_data_get_irq_chip_data(data);
458 
459 	agent->imr &= ~BIT(data->irq - agent->irq_base);
460 	agent->imr_change_pending = true;
461 }
462 
463 static int twl4030_sih_set_type(struct irq_data *data, unsigned trigger)
464 {
465 	struct sih_agent *agent = irq_data_get_irq_chip_data(data);
466 
467 	if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
468 		return -EINVAL;
469 
470 	if (irqd_get_trigger_type(data) != trigger)
471 		agent->edge_change |= BIT(data->irq - agent->irq_base);
472 
473 	return 0;
474 }
475 
476 static void twl4030_sih_bus_lock(struct irq_data *data)
477 {
478 	struct sih_agent	*agent = irq_data_get_irq_chip_data(data);
479 
480 	mutex_lock(&agent->irq_lock);
481 }
482 
483 static void twl4030_sih_bus_sync_unlock(struct irq_data *data)
484 {
485 	struct sih_agent	*agent = irq_data_get_irq_chip_data(data);
486 	const struct sih	*sih = agent->sih;
487 	int			status;
488 
489 	if (agent->imr_change_pending) {
490 		union {
491 			u32	word;
492 			u8	bytes[4];
493 		} imr;
494 
495 		/* byte[0] gets overwritten as we write ... */
496 		imr.word = cpu_to_le32(agent->imr << 8);
497 		agent->imr_change_pending = false;
498 
499 		/* write the whole mask ... simpler than subsetting it */
500 		status = twl_i2c_write(sih->module, imr.bytes,
501 				sih->mask[irq_line].imr_offset,
502 				sih->bytes_ixr);
503 		if (status)
504 			pr_err("twl4030: %s, %s --> %d\n", __func__,
505 					"write", status);
506 	}
507 
508 	if (agent->edge_change) {
509 		u32		edge_change;
510 		u8		bytes[6];
511 
512 		edge_change = agent->edge_change;
513 		agent->edge_change = 0;
514 
515 		/*
516 		 * Read, reserving first byte for write scratch.  Yes, this
517 		 * could be cached for some speedup ... but be careful about
518 		 * any processor on the other IRQ line, EDR registers are
519 		 * shared.
520 		 */
521 		status = twl_i2c_read(sih->module, bytes + 1,
522 				sih->edr_offset, sih->bytes_edr);
523 		if (status) {
524 			pr_err("twl4030: %s, %s --> %d\n", __func__,
525 					"read", status);
526 			return;
527 		}
528 
529 		/* Modify only the bits we know must change */
530 		while (edge_change) {
531 			int		i = fls(edge_change) - 1;
532 			struct irq_data	*idata;
533 			int		byte = 1 + (i >> 2);
534 			int		off = (i & 0x3) * 2;
535 			unsigned int	type;
536 
537 			idata = irq_get_irq_data(i + agent->irq_base);
538 
539 			bytes[byte] &= ~(0x03 << off);
540 
541 			type = irqd_get_trigger_type(idata);
542 			if (type & IRQ_TYPE_EDGE_RISING)
543 				bytes[byte] |= BIT(off + 1);
544 			if (type & IRQ_TYPE_EDGE_FALLING)
545 				bytes[byte] |= BIT(off + 0);
546 
547 			edge_change &= ~BIT(i);
548 		}
549 
550 		/* Write */
551 		status = twl_i2c_write(sih->module, bytes,
552 				sih->edr_offset, sih->bytes_edr);
553 		if (status)
554 			pr_err("twl4030: %s, %s --> %d\n", __func__,
555 					"write", status);
556 	}
557 
558 	mutex_unlock(&agent->irq_lock);
559 }
560 
561 static struct irq_chip twl4030_sih_irq_chip = {
562 	.name		= "twl4030",
563 	.irq_mask	= twl4030_sih_mask,
564 	.irq_unmask	= twl4030_sih_unmask,
565 	.irq_set_type	= twl4030_sih_set_type,
566 	.irq_bus_lock	= twl4030_sih_bus_lock,
567 	.irq_bus_sync_unlock = twl4030_sih_bus_sync_unlock,
568 };
569 
570 /*----------------------------------------------------------------------*/
571 
572 static inline int sih_read_isr(const struct sih *sih)
573 {
574 	int status;
575 	union {
576 		u8 bytes[4];
577 		u32 word;
578 	} isr;
579 
580 	/* FIXME need retry-on-error ... */
581 
582 	isr.word = 0;
583 	status = twl_i2c_read(sih->module, isr.bytes,
584 			sih->mask[irq_line].isr_offset, sih->bytes_ixr);
585 
586 	return (status < 0) ? status : le32_to_cpu(isr.word);
587 }
588 
589 /*
590  * Generic handler for SIH interrupts ... we "know" this is called
591  * in task context, with IRQs enabled.
592  */
593 static irqreturn_t handle_twl4030_sih(int irq, void *data)
594 {
595 	struct sih_agent *agent = irq_get_handler_data(irq);
596 	const struct sih *sih = agent->sih;
597 	int isr;
598 
599 	/* reading ISR acks the IRQs, using clear-on-read mode */
600 	isr = sih_read_isr(sih);
601 
602 	if (isr < 0) {
603 		pr_err("twl4030: %s SIH, read ISR error %d\n",
604 			sih->name, isr);
605 		/* REVISIT:  recover; eventually mask it all, etc */
606 		return IRQ_HANDLED;
607 	}
608 
609 	while (isr) {
610 		irq = fls(isr);
611 		irq--;
612 		isr &= ~BIT(irq);
613 
614 		if (irq < sih->bits)
615 			handle_nested_irq(agent->irq_base + irq);
616 		else
617 			pr_err("twl4030: %s SIH, invalid ISR bit %d\n",
618 				sih->name, irq);
619 	}
620 	return IRQ_HANDLED;
621 }
622 
623 static unsigned twl4030_irq_next;
624 
625 /* returns the first IRQ used by this SIH bank,
626  * or negative errno
627  */
628 int twl4030_sih_setup(int module)
629 {
630 	int			sih_mod;
631 	const struct sih	*sih = NULL;
632 	struct sih_agent	*agent;
633 	int			i, irq;
634 	int			status = -EINVAL;
635 	unsigned		irq_base = twl4030_irq_next;
636 
637 	/* only support modules with standard clear-on-read for now */
638 	for (sih_mod = 0, sih = sih_modules;
639 			sih_mod < nr_sih_modules;
640 			sih_mod++, sih++) {
641 		if (sih->module == module && sih->set_cor) {
642 			if (!WARN((irq_base + sih->bits) > NR_IRQS,
643 					"irq %d for %s too big\n",
644 					irq_base + sih->bits,
645 					sih->name))
646 				status = 0;
647 			break;
648 		}
649 	}
650 	if (status < 0)
651 		return status;
652 
653 	agent = kzalloc(sizeof *agent, GFP_KERNEL);
654 	if (!agent)
655 		return -ENOMEM;
656 
657 	status = 0;
658 
659 	agent->irq_base = irq_base;
660 	agent->sih = sih;
661 	agent->imr = ~0;
662 	mutex_init(&agent->irq_lock);
663 
664 	for (i = 0; i < sih->bits; i++) {
665 		irq = irq_base + i;
666 
667 		irq_set_chip_data(irq, agent);
668 		irq_set_chip_and_handler(irq, &twl4030_sih_irq_chip,
669 					 handle_edge_irq);
670 		irq_set_nested_thread(irq, 1);
671 		activate_irq(irq);
672 	}
673 
674 	twl4030_irq_next += i;
675 
676 	/* replace generic PIH handler (handle_simple_irq) */
677 	irq = sih_mod + twl4030_irq_base;
678 	irq_set_handler_data(irq, agent);
679 	agent->irq_name = kasprintf(GFP_KERNEL, "twl4030_%s", sih->name);
680 	status = request_threaded_irq(irq, NULL, handle_twl4030_sih, 0,
681 				      agent->irq_name ?: sih->name, NULL);
682 
683 	pr_info("twl4030: %s (irq %d) chaining IRQs %d..%d\n", sih->name,
684 			irq, irq_base, twl4030_irq_next - 1);
685 
686 	return status < 0 ? status : irq_base;
687 }
688 
689 /* FIXME need a call to reverse twl4030_sih_setup() ... */
690 
691 
692 /*----------------------------------------------------------------------*/
693 
694 /* FIXME pass in which interrupt line we'll use ... */
695 #define twl_irq_line	0
696 
697 int twl4030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
698 {
699 	static struct irq_chip	twl4030_irq_chip;
700 
701 	int			status;
702 	int			i;
703 
704 	/*
705 	 * Mask and clear all TWL4030 interrupts since initially we do
706 	 * not have any TWL4030 module interrupt handlers present
707 	 */
708 	status = twl4030_init_sih_modules(twl_irq_line);
709 	if (status < 0)
710 		return status;
711 
712 	twl4030_irq_base = irq_base;
713 
714 	/* install an irq handler for each of the SIH modules;
715 	 * clone dummy irq_chip since PIH can't *do* anything
716 	 */
717 	twl4030_irq_chip = dummy_irq_chip;
718 	twl4030_irq_chip.name = "twl4030";
719 
720 	twl4030_sih_irq_chip.irq_ack = dummy_irq_chip.irq_ack;
721 
722 	for (i = irq_base; i < irq_end; i++) {
723 		irq_set_chip_and_handler(i, &twl4030_irq_chip,
724 					 handle_simple_irq);
725 		irq_set_nested_thread(i, 1);
726 		activate_irq(i);
727 	}
728 	twl4030_irq_next = i;
729 	pr_info("twl4030: %s (irq %d) chaining IRQs %d..%d\n", "PIH",
730 			irq_num, irq_base, twl4030_irq_next - 1);
731 
732 	/* ... and the PWR_INT module ... */
733 	status = twl4030_sih_setup(TWL4030_MODULE_INT);
734 	if (status < 0) {
735 		pr_err("twl4030: sih_setup PWR INT --> %d\n", status);
736 		goto fail;
737 	}
738 
739 	/* install an irq handler to demultiplex the TWL4030 interrupt */
740 	status = request_threaded_irq(irq_num, NULL, handle_twl4030_pih,
741 				      IRQF_ONESHOT,
742 				      "TWL4030-PIH", NULL);
743 	if (status < 0) {
744 		pr_err("twl4030: could not claim irq%d: %d\n", irq_num, status);
745 		goto fail_rqirq;
746 	}
747 
748 	return status;
749 fail_rqirq:
750 	/* clean up twl4030_sih_setup */
751 fail:
752 	for (i = irq_base; i < irq_end; i++) {
753 		irq_set_nested_thread(i, 0);
754 		irq_set_chip_and_handler(i, NULL, NULL);
755 	}
756 
757 	return status;
758 }
759 
760 int twl4030_exit_irq(void)
761 {
762 	/* FIXME undo twl_init_irq() */
763 	if (twl4030_irq_base) {
764 		pr_err("twl4030: can't yet clean up IRQs?\n");
765 		return -ENOSYS;
766 	}
767 	return 0;
768 }
769 
770 int twl4030_init_chip_irq(const char *chip)
771 {
772 	if (!strcmp(chip, "twl5031")) {
773 		sih_modules = sih_modules_twl5031;
774 		nr_sih_modules = ARRAY_SIZE(sih_modules_twl5031);
775 	} else {
776 		sih_modules = sih_modules_twl4030;
777 		nr_sih_modules = ARRAY_SIZE(sih_modules_twl4030);
778 	}
779 
780 	return 0;
781 }
782