xref: /linux/drivers/gpio/gpio-eic-sprd.c (revision 856e7c4b619af622d56b3b454f7bec32a170ac99)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2018 Spreadtrum Communications Inc.
4  * Copyright (C) 2018 Linaro Ltd.
5  */
6 
7 #include <linux/bitops.h>
8 #include <linux/gpio/driver.h>
9 #include <linux/interrupt.h>
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/of_device.h>
13 #include <linux/platform_device.h>
14 #include <linux/spinlock.h>
15 
16 /* EIC registers definition */
17 #define SPRD_EIC_DBNC_DATA		0x0
18 #define SPRD_EIC_DBNC_DMSK		0x4
19 #define SPRD_EIC_DBNC_IEV		0x14
20 #define SPRD_EIC_DBNC_IE		0x18
21 #define SPRD_EIC_DBNC_RIS		0x1c
22 #define SPRD_EIC_DBNC_MIS		0x20
23 #define SPRD_EIC_DBNC_IC		0x24
24 #define SPRD_EIC_DBNC_TRIG		0x28
25 #define SPRD_EIC_DBNC_CTRL0		0x40
26 
27 #define SPRD_EIC_LATCH_INTEN		0x0
28 #define SPRD_EIC_LATCH_INTRAW		0x4
29 #define SPRD_EIC_LATCH_INTMSK		0x8
30 #define SPRD_EIC_LATCH_INTCLR		0xc
31 #define SPRD_EIC_LATCH_INTPOL		0x10
32 #define SPRD_EIC_LATCH_INTMODE		0x14
33 
34 #define SPRD_EIC_ASYNC_INTIE		0x0
35 #define SPRD_EIC_ASYNC_INTRAW		0x4
36 #define SPRD_EIC_ASYNC_INTMSK		0x8
37 #define SPRD_EIC_ASYNC_INTCLR		0xc
38 #define SPRD_EIC_ASYNC_INTMODE		0x10
39 #define SPRD_EIC_ASYNC_INTBOTH		0x14
40 #define SPRD_EIC_ASYNC_INTPOL		0x18
41 #define SPRD_EIC_ASYNC_DATA		0x1c
42 
43 #define SPRD_EIC_SYNC_INTIE		0x0
44 #define SPRD_EIC_SYNC_INTRAW		0x4
45 #define SPRD_EIC_SYNC_INTMSK		0x8
46 #define SPRD_EIC_SYNC_INTCLR		0xc
47 #define SPRD_EIC_SYNC_INTMODE		0x10
48 #define SPRD_EIC_SYNC_INTBOTH		0x14
49 #define SPRD_EIC_SYNC_INTPOL		0x18
50 #define SPRD_EIC_SYNC_DATA		0x1c
51 
52 /*
53  * The digital-chip EIC controller can support maximum 3 banks, and each bank
54  * contains 8 EICs.
55  */
56 #define SPRD_EIC_MAX_BANK		3
57 #define SPRD_EIC_PER_BANK_NR		8
58 #define SPRD_EIC_DATA_MASK		GENMASK(7, 0)
59 #define SPRD_EIC_BIT(x)			((x) & (SPRD_EIC_PER_BANK_NR - 1))
60 #define SPRD_EIC_DBNC_MASK		GENMASK(11, 0)
61 
62 /*
63  * The Spreadtrum EIC (external interrupt controller) can be used only in
64  * input mode to generate interrupts if detecting input signals.
65  *
66  * The Spreadtrum digital-chip EIC controller contains 4 sub-modules:
67  * debounce EIC, latch EIC, async EIC and sync EIC,
68  *
69  * The debounce EIC is used to capture the input signals' stable status
70  * (millisecond resolution) and a single-trigger mechanism is introduced
71  * into this sub-module to enhance the input event detection reliability.
72  * The debounce range is from 1ms to 4s with a step size of 1ms.
73  *
74  * The latch EIC is used to latch some special power down signals and
75  * generate interrupts, since the latch EIC does not depend on the APB clock
76  * to capture signals.
77  *
78  * The async EIC uses a 32k clock to capture the short signals (microsecond
79  * resolution) to generate interrupts by level or edge trigger.
80  *
81  * The EIC-sync is similar with GPIO's input function, which is a synchronized
82  * signal input register.
83  */
84 enum sprd_eic_type {
85 	SPRD_EIC_DEBOUNCE,
86 	SPRD_EIC_LATCH,
87 	SPRD_EIC_ASYNC,
88 	SPRD_EIC_SYNC,
89 	SPRD_EIC_MAX,
90 };
91 
92 struct sprd_eic {
93 	struct gpio_chip chip;
94 	struct irq_chip intc;
95 	void __iomem *base[SPRD_EIC_MAX_BANK];
96 	enum sprd_eic_type type;
97 	spinlock_t lock;
98 	int irq;
99 };
100 
101 struct sprd_eic_variant_data {
102 	enum sprd_eic_type type;
103 	u32 num_eics;
104 };
105 
106 static const char *sprd_eic_label_name[SPRD_EIC_MAX] = {
107 	"eic-debounce", "eic-latch", "eic-async",
108 	"eic-sync",
109 };
110 
111 static const struct sprd_eic_variant_data sc9860_eic_dbnc_data = {
112 	.type = SPRD_EIC_DEBOUNCE,
113 	.num_eics = 8,
114 };
115 
116 static const struct sprd_eic_variant_data sc9860_eic_latch_data = {
117 	.type = SPRD_EIC_LATCH,
118 	.num_eics = 8,
119 };
120 
121 static const struct sprd_eic_variant_data sc9860_eic_async_data = {
122 	.type = SPRD_EIC_ASYNC,
123 	.num_eics = 8,
124 };
125 
126 static const struct sprd_eic_variant_data sc9860_eic_sync_data = {
127 	.type = SPRD_EIC_SYNC,
128 	.num_eics = 8,
129 };
130 
131 static inline void __iomem *sprd_eic_offset_base(struct sprd_eic *sprd_eic,
132 						 unsigned int bank)
133 {
134 	if (bank >= SPRD_EIC_MAX_BANK)
135 		return NULL;
136 
137 	return sprd_eic->base[bank];
138 }
139 
140 static void sprd_eic_update(struct gpio_chip *chip, unsigned int offset,
141 			    u16 reg, unsigned int val)
142 {
143 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
144 	void __iomem *base =
145 		sprd_eic_offset_base(sprd_eic, offset / SPRD_EIC_PER_BANK_NR);
146 	unsigned long flags;
147 	u32 tmp;
148 
149 	spin_lock_irqsave(&sprd_eic->lock, flags);
150 	tmp = readl_relaxed(base + reg);
151 
152 	if (val)
153 		tmp |= BIT(SPRD_EIC_BIT(offset));
154 	else
155 		tmp &= ~BIT(SPRD_EIC_BIT(offset));
156 
157 	writel_relaxed(tmp, base + reg);
158 	spin_unlock_irqrestore(&sprd_eic->lock, flags);
159 }
160 
161 static int sprd_eic_read(struct gpio_chip *chip, unsigned int offset, u16 reg)
162 {
163 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
164 	void __iomem *base =
165 		sprd_eic_offset_base(sprd_eic, offset / SPRD_EIC_PER_BANK_NR);
166 
167 	return !!(readl_relaxed(base + reg) & BIT(SPRD_EIC_BIT(offset)));
168 }
169 
170 static int sprd_eic_request(struct gpio_chip *chip, unsigned int offset)
171 {
172 	sprd_eic_update(chip, offset, SPRD_EIC_DBNC_DMSK, 1);
173 	return 0;
174 }
175 
176 static void sprd_eic_free(struct gpio_chip *chip, unsigned int offset)
177 {
178 	sprd_eic_update(chip, offset, SPRD_EIC_DBNC_DMSK, 0);
179 }
180 
181 static int sprd_eic_get(struct gpio_chip *chip, unsigned int offset)
182 {
183 	return sprd_eic_read(chip, offset, SPRD_EIC_DBNC_DATA);
184 }
185 
186 static int sprd_eic_direction_input(struct gpio_chip *chip, unsigned int offset)
187 {
188 	/* EICs are always input, nothing need to do here. */
189 	return 0;
190 }
191 
192 static void sprd_eic_set(struct gpio_chip *chip, unsigned int offset, int value)
193 {
194 	/* EICs are always input, nothing need to do here. */
195 }
196 
197 static int sprd_eic_set_debounce(struct gpio_chip *chip, unsigned int offset,
198 				 unsigned int debounce)
199 {
200 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
201 	void __iomem *base =
202 		sprd_eic_offset_base(sprd_eic, offset / SPRD_EIC_PER_BANK_NR);
203 	u32 reg = SPRD_EIC_DBNC_CTRL0 + SPRD_EIC_BIT(offset) * 0x4;
204 	u32 value = readl_relaxed(base + reg) & ~SPRD_EIC_DBNC_MASK;
205 
206 	value |= (debounce / 1000) & SPRD_EIC_DBNC_MASK;
207 	writel_relaxed(value, base + reg);
208 
209 	return 0;
210 }
211 
212 static int sprd_eic_set_config(struct gpio_chip *chip, unsigned int offset,
213 			       unsigned long config)
214 {
215 	unsigned long param = pinconf_to_config_param(config);
216 	u32 arg = pinconf_to_config_argument(config);
217 
218 	if (param == PIN_CONFIG_INPUT_DEBOUNCE)
219 		return sprd_eic_set_debounce(chip, offset, arg);
220 
221 	return -ENOTSUPP;
222 }
223 
224 static void sprd_eic_irq_mask(struct irq_data *data)
225 {
226 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
227 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
228 	u32 offset = irqd_to_hwirq(data);
229 
230 	switch (sprd_eic->type) {
231 	case SPRD_EIC_DEBOUNCE:
232 		sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IE, 0);
233 		sprd_eic_update(chip, offset, SPRD_EIC_DBNC_TRIG, 0);
234 		break;
235 	case SPRD_EIC_LATCH:
236 		sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTEN, 0);
237 		break;
238 	case SPRD_EIC_ASYNC:
239 		sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTIE, 0);
240 		break;
241 	case SPRD_EIC_SYNC:
242 		sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTIE, 0);
243 		break;
244 	default:
245 		dev_err(chip->parent, "Unsupported EIC type.\n");
246 	}
247 }
248 
249 static void sprd_eic_irq_unmask(struct irq_data *data)
250 {
251 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
252 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
253 	u32 offset = irqd_to_hwirq(data);
254 
255 	switch (sprd_eic->type) {
256 	case SPRD_EIC_DEBOUNCE:
257 		sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IE, 1);
258 		sprd_eic_update(chip, offset, SPRD_EIC_DBNC_TRIG, 1);
259 		break;
260 	case SPRD_EIC_LATCH:
261 		sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTEN, 1);
262 		break;
263 	case SPRD_EIC_ASYNC:
264 		sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTIE, 1);
265 		break;
266 	case SPRD_EIC_SYNC:
267 		sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTIE, 1);
268 		break;
269 	default:
270 		dev_err(chip->parent, "Unsupported EIC type.\n");
271 	}
272 }
273 
274 static void sprd_eic_irq_ack(struct irq_data *data)
275 {
276 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
277 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
278 	u32 offset = irqd_to_hwirq(data);
279 
280 	switch (sprd_eic->type) {
281 	case SPRD_EIC_DEBOUNCE:
282 		sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IC, 1);
283 		break;
284 	case SPRD_EIC_LATCH:
285 		sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTCLR, 1);
286 		break;
287 	case SPRD_EIC_ASYNC:
288 		sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTCLR, 1);
289 		break;
290 	case SPRD_EIC_SYNC:
291 		sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTCLR, 1);
292 		break;
293 	default:
294 		dev_err(chip->parent, "Unsupported EIC type.\n");
295 	}
296 }
297 
298 static int sprd_eic_irq_set_type(struct irq_data *data, unsigned int flow_type)
299 {
300 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
301 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
302 	u32 offset = irqd_to_hwirq(data);
303 	int state;
304 
305 	switch (sprd_eic->type) {
306 	case SPRD_EIC_DEBOUNCE:
307 		switch (flow_type) {
308 		case IRQ_TYPE_LEVEL_HIGH:
309 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IEV, 1);
310 			break;
311 		case IRQ_TYPE_LEVEL_LOW:
312 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IEV, 0);
313 			break;
314 		case IRQ_TYPE_EDGE_RISING:
315 		case IRQ_TYPE_EDGE_FALLING:
316 		case IRQ_TYPE_EDGE_BOTH:
317 			state = sprd_eic_get(chip, offset);
318 			if (state)
319 				sprd_eic_update(chip, offset,
320 						SPRD_EIC_DBNC_IEV, 0);
321 			else
322 				sprd_eic_update(chip, offset,
323 						SPRD_EIC_DBNC_IEV, 1);
324 			break;
325 		default:
326 			return -ENOTSUPP;
327 		}
328 
329 		irq_set_handler_locked(data, handle_level_irq);
330 		break;
331 	case SPRD_EIC_LATCH:
332 		switch (flow_type) {
333 		case IRQ_TYPE_LEVEL_HIGH:
334 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTPOL, 0);
335 			break;
336 		case IRQ_TYPE_LEVEL_LOW:
337 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTPOL, 1);
338 			break;
339 		case IRQ_TYPE_EDGE_RISING:
340 		case IRQ_TYPE_EDGE_FALLING:
341 		case IRQ_TYPE_EDGE_BOTH:
342 			state = sprd_eic_get(chip, offset);
343 			if (state)
344 				sprd_eic_update(chip, offset,
345 						SPRD_EIC_LATCH_INTPOL, 0);
346 			else
347 				sprd_eic_update(chip, offset,
348 						SPRD_EIC_LATCH_INTPOL, 1);
349 			break;
350 		default:
351 			return -ENOTSUPP;
352 		}
353 
354 		irq_set_handler_locked(data, handle_level_irq);
355 		break;
356 	case SPRD_EIC_ASYNC:
357 		switch (flow_type) {
358 		case IRQ_TYPE_EDGE_RISING:
359 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 0);
360 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 0);
361 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTPOL, 1);
362 			irq_set_handler_locked(data, handle_edge_irq);
363 			break;
364 		case IRQ_TYPE_EDGE_FALLING:
365 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 0);
366 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 0);
367 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTPOL, 0);
368 			irq_set_handler_locked(data, handle_edge_irq);
369 			break;
370 		case IRQ_TYPE_EDGE_BOTH:
371 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 1);
372 			irq_set_handler_locked(data, handle_edge_irq);
373 			break;
374 		case IRQ_TYPE_LEVEL_HIGH:
375 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 0);
376 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 1);
377 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTPOL, 1);
378 			irq_set_handler_locked(data, handle_level_irq);
379 			break;
380 		case IRQ_TYPE_LEVEL_LOW:
381 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 0);
382 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 1);
383 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTPOL, 0);
384 			irq_set_handler_locked(data, handle_level_irq);
385 			break;
386 		default:
387 			return -ENOTSUPP;
388 		}
389 		break;
390 	case SPRD_EIC_SYNC:
391 		switch (flow_type) {
392 		case IRQ_TYPE_EDGE_RISING:
393 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 0);
394 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 0);
395 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTPOL, 1);
396 			irq_set_handler_locked(data, handle_edge_irq);
397 			break;
398 		case IRQ_TYPE_EDGE_FALLING:
399 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 0);
400 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 0);
401 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTPOL, 0);
402 			irq_set_handler_locked(data, handle_edge_irq);
403 			break;
404 		case IRQ_TYPE_EDGE_BOTH:
405 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 1);
406 			irq_set_handler_locked(data, handle_edge_irq);
407 			break;
408 		case IRQ_TYPE_LEVEL_HIGH:
409 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 0);
410 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 1);
411 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTPOL, 1);
412 			irq_set_handler_locked(data, handle_level_irq);
413 			break;
414 		case IRQ_TYPE_LEVEL_LOW:
415 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 0);
416 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 1);
417 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTPOL, 0);
418 			irq_set_handler_locked(data, handle_level_irq);
419 			break;
420 		default:
421 			return -ENOTSUPP;
422 		}
423 	default:
424 		dev_err(chip->parent, "Unsupported EIC type.\n");
425 		return -ENOTSUPP;
426 	}
427 
428 	return 0;
429 }
430 
431 static void sprd_eic_toggle_trigger(struct gpio_chip *chip, unsigned int irq,
432 				    unsigned int offset)
433 {
434 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
435 	struct irq_data *data = irq_get_irq_data(irq);
436 	u32 trigger = irqd_get_trigger_type(data);
437 	int state, post_state;
438 
439 	/*
440 	 * The debounce EIC and latch EIC can only support level trigger, so we
441 	 * can toggle the level trigger to emulate the edge trigger.
442 	 */
443 	if ((sprd_eic->type != SPRD_EIC_DEBOUNCE &&
444 	     sprd_eic->type != SPRD_EIC_LATCH) ||
445 	    !(trigger & IRQ_TYPE_EDGE_BOTH))
446 		return;
447 
448 	sprd_eic_irq_mask(data);
449 	state = sprd_eic_get(chip, offset);
450 
451 retry:
452 	switch (sprd_eic->type) {
453 	case SPRD_EIC_DEBOUNCE:
454 		if (state)
455 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IEV, 0);
456 		else
457 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IEV, 1);
458 		break;
459 	case SPRD_EIC_LATCH:
460 		if (state)
461 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTPOL, 0);
462 		else
463 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTPOL, 1);
464 		break;
465 	default:
466 		sprd_eic_irq_unmask(data);
467 		return;
468 	}
469 
470 	post_state = sprd_eic_get(chip, offset);
471 	if (state != post_state) {
472 		dev_warn(chip->parent, "EIC level was changed.\n");
473 		state = post_state;
474 		goto retry;
475 	}
476 
477 	sprd_eic_irq_unmask(data);
478 }
479 
480 static int sprd_eic_match_chip_by_type(struct gpio_chip *chip, void *data)
481 {
482 	enum sprd_eic_type type = *(enum sprd_eic_type *)data;
483 
484 	return !strcmp(chip->label, sprd_eic_label_name[type]);
485 }
486 
487 static void sprd_eic_handle_one_type(struct gpio_chip *chip)
488 {
489 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
490 	u32 bank, n, girq;
491 
492 	for (bank = 0; bank * SPRD_EIC_PER_BANK_NR < chip->ngpio; bank++) {
493 		void __iomem *base = sprd_eic_offset_base(sprd_eic, bank);
494 		unsigned long reg;
495 
496 		switch (sprd_eic->type) {
497 		case SPRD_EIC_DEBOUNCE:
498 			reg = readl_relaxed(base + SPRD_EIC_DBNC_MIS) &
499 				SPRD_EIC_DATA_MASK;
500 			break;
501 		case SPRD_EIC_LATCH:
502 			reg = readl_relaxed(base + SPRD_EIC_LATCH_INTMSK) &
503 				SPRD_EIC_DATA_MASK;
504 			break;
505 		case SPRD_EIC_ASYNC:
506 			reg = readl_relaxed(base + SPRD_EIC_ASYNC_INTMSK) &
507 				SPRD_EIC_DATA_MASK;
508 			break;
509 		case SPRD_EIC_SYNC:
510 			reg = readl_relaxed(base + SPRD_EIC_SYNC_INTMSK) &
511 				SPRD_EIC_DATA_MASK;
512 			break;
513 		default:
514 			dev_err(chip->parent, "Unsupported EIC type.\n");
515 			return;
516 		}
517 
518 		for_each_set_bit(n, &reg, SPRD_EIC_PER_BANK_NR) {
519 			girq = irq_find_mapping(chip->irq.domain,
520 					bank * SPRD_EIC_PER_BANK_NR + n);
521 
522 			generic_handle_irq(girq);
523 			sprd_eic_toggle_trigger(chip, girq, n);
524 		}
525 	}
526 }
527 
528 static void sprd_eic_irq_handler(struct irq_desc *desc)
529 {
530 	struct irq_chip *ic = irq_desc_get_chip(desc);
531 	struct gpio_chip *chip;
532 	enum sprd_eic_type type;
533 
534 	chained_irq_enter(ic, desc);
535 
536 	/*
537 	 * Since the digital-chip EIC 4 sub-modules (debounce, latch, async
538 	 * and sync) share one same interrupt line, we should iterate each
539 	 * EIC module to check if there are EIC interrupts were triggered.
540 	 */
541 	for (type = SPRD_EIC_DEBOUNCE; type < SPRD_EIC_MAX; type++) {
542 		chip = gpiochip_find(&type, sprd_eic_match_chip_by_type);
543 		if (!chip)
544 			continue;
545 
546 		sprd_eic_handle_one_type(chip);
547 	}
548 
549 	chained_irq_exit(ic, desc);
550 }
551 
552 static int sprd_eic_probe(struct platform_device *pdev)
553 {
554 	const struct sprd_eic_variant_data *pdata;
555 	struct gpio_irq_chip *irq;
556 	struct sprd_eic *sprd_eic;
557 	struct resource *res;
558 	int ret, i;
559 
560 	pdata = of_device_get_match_data(&pdev->dev);
561 	if (!pdata) {
562 		dev_err(&pdev->dev, "No matching driver data found.\n");
563 		return -EINVAL;
564 	}
565 
566 	sprd_eic = devm_kzalloc(&pdev->dev, sizeof(*sprd_eic), GFP_KERNEL);
567 	if (!sprd_eic)
568 		return -ENOMEM;
569 
570 	spin_lock_init(&sprd_eic->lock);
571 	sprd_eic->type = pdata->type;
572 
573 	sprd_eic->irq = platform_get_irq(pdev, 0);
574 	if (sprd_eic->irq < 0) {
575 		dev_err(&pdev->dev, "Failed to get EIC interrupt.\n");
576 		return sprd_eic->irq;
577 	}
578 
579 	for (i = 0; i < SPRD_EIC_MAX_BANK; i++) {
580 		/*
581 		 * We can have maximum 3 banks EICs, and each EIC has
582 		 * its own base address. But some platform maybe only
583 		 * have one bank EIC, thus base[1] and base[2] can be
584 		 * optional.
585 		 */
586 		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
587 		if (!res)
588 			continue;
589 
590 		sprd_eic->base[i] = devm_ioremap_resource(&pdev->dev, res);
591 		if (IS_ERR(sprd_eic->base[i]))
592 			return PTR_ERR(sprd_eic->base[i]);
593 	}
594 
595 	sprd_eic->chip.label = sprd_eic_label_name[sprd_eic->type];
596 	sprd_eic->chip.ngpio = pdata->num_eics;
597 	sprd_eic->chip.base = -1;
598 	sprd_eic->chip.parent = &pdev->dev;
599 	sprd_eic->chip.of_node = pdev->dev.of_node;
600 	sprd_eic->chip.direction_input = sprd_eic_direction_input;
601 	switch (sprd_eic->type) {
602 	case SPRD_EIC_DEBOUNCE:
603 		sprd_eic->chip.request = sprd_eic_request;
604 		sprd_eic->chip.free = sprd_eic_free;
605 		sprd_eic->chip.set_config = sprd_eic_set_config;
606 		sprd_eic->chip.set = sprd_eic_set;
607 		/* fall-through */
608 	case SPRD_EIC_ASYNC:
609 		/* fall-through */
610 	case SPRD_EIC_SYNC:
611 		sprd_eic->chip.get = sprd_eic_get;
612 		break;
613 	case SPRD_EIC_LATCH:
614 		/* fall-through */
615 	default:
616 		break;
617 	}
618 
619 	sprd_eic->intc.name = dev_name(&pdev->dev);
620 	sprd_eic->intc.irq_ack = sprd_eic_irq_ack;
621 	sprd_eic->intc.irq_mask = sprd_eic_irq_mask;
622 	sprd_eic->intc.irq_unmask = sprd_eic_irq_unmask;
623 	sprd_eic->intc.irq_set_type = sprd_eic_irq_set_type;
624 	sprd_eic->intc.flags = IRQCHIP_SKIP_SET_WAKE;
625 
626 	irq = &sprd_eic->chip.irq;
627 	irq->chip = &sprd_eic->intc;
628 	irq->handler = handle_bad_irq;
629 	irq->default_type = IRQ_TYPE_NONE;
630 	irq->parent_handler = sprd_eic_irq_handler;
631 	irq->parent_handler_data = sprd_eic;
632 	irq->num_parents = 1;
633 	irq->parents = &sprd_eic->irq;
634 
635 	ret = devm_gpiochip_add_data(&pdev->dev, &sprd_eic->chip, sprd_eic);
636 	if (ret < 0) {
637 		dev_err(&pdev->dev, "Could not register gpiochip %d.\n", ret);
638 		return ret;
639 	}
640 
641 	platform_set_drvdata(pdev, sprd_eic);
642 	return 0;
643 }
644 
645 static const struct of_device_id sprd_eic_of_match[] = {
646 	{
647 		.compatible = "sprd,sc9860-eic-debounce",
648 		.data = &sc9860_eic_dbnc_data,
649 	},
650 	{
651 		.compatible = "sprd,sc9860-eic-latch",
652 		.data = &sc9860_eic_latch_data,
653 	},
654 	{
655 		.compatible = "sprd,sc9860-eic-async",
656 		.data = &sc9860_eic_async_data,
657 	},
658 	{
659 		.compatible = "sprd,sc9860-eic-sync",
660 		.data = &sc9860_eic_sync_data,
661 	},
662 	{
663 		/* end of list */
664 	}
665 };
666 MODULE_DEVICE_TABLE(of, sprd_eic_of_match);
667 
668 static struct platform_driver sprd_eic_driver = {
669 	.probe = sprd_eic_probe,
670 	.driver = {
671 		.name = "sprd-eic",
672 		.of_match_table	= sprd_eic_of_match,
673 	},
674 };
675 
676 module_platform_driver(sprd_eic_driver);
677 
678 MODULE_DESCRIPTION("Spreadtrum EIC driver");
679 MODULE_LICENSE("GPL v2");
680