xref: /linux/drivers/gpio/gpio-eic-sprd.c (revision f4738f56d1dc62aaba69b33702a5ab098f1b8c63)
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.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 	void __iomem *base[SPRD_EIC_MAX_BANK];
95 	enum sprd_eic_type type;
96 	spinlock_t lock;
97 	int irq;
98 };
99 
100 struct sprd_eic_variant_data {
101 	enum sprd_eic_type type;
102 	u32 num_eics;
103 };
104 
105 static const char *sprd_eic_label_name[SPRD_EIC_MAX] = {
106 	"eic-debounce", "eic-latch", "eic-async",
107 	"eic-sync",
108 };
109 
110 static const struct sprd_eic_variant_data sc9860_eic_dbnc_data = {
111 	.type = SPRD_EIC_DEBOUNCE,
112 	.num_eics = 8,
113 };
114 
115 static const struct sprd_eic_variant_data sc9860_eic_latch_data = {
116 	.type = SPRD_EIC_LATCH,
117 	.num_eics = 8,
118 };
119 
120 static const struct sprd_eic_variant_data sc9860_eic_async_data = {
121 	.type = SPRD_EIC_ASYNC,
122 	.num_eics = 8,
123 };
124 
125 static const struct sprd_eic_variant_data sc9860_eic_sync_data = {
126 	.type = SPRD_EIC_SYNC,
127 	.num_eics = 8,
128 };
129 
130 static inline void __iomem *sprd_eic_offset_base(struct sprd_eic *sprd_eic,
131 						 unsigned int bank)
132 {
133 	if (bank >= SPRD_EIC_MAX_BANK)
134 		return NULL;
135 
136 	return sprd_eic->base[bank];
137 }
138 
139 static void sprd_eic_update(struct gpio_chip *chip, unsigned int offset,
140 			    u16 reg, unsigned int val)
141 {
142 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
143 	void __iomem *base =
144 		sprd_eic_offset_base(sprd_eic, offset / SPRD_EIC_PER_BANK_NR);
145 	unsigned long flags;
146 	u32 tmp;
147 
148 	spin_lock_irqsave(&sprd_eic->lock, flags);
149 	tmp = readl_relaxed(base + reg);
150 
151 	if (val)
152 		tmp |= BIT(SPRD_EIC_BIT(offset));
153 	else
154 		tmp &= ~BIT(SPRD_EIC_BIT(offset));
155 
156 	writel_relaxed(tmp, base + reg);
157 	spin_unlock_irqrestore(&sprd_eic->lock, flags);
158 }
159 
160 static int sprd_eic_read(struct gpio_chip *chip, unsigned int offset, u16 reg)
161 {
162 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
163 	void __iomem *base =
164 		sprd_eic_offset_base(sprd_eic, offset / SPRD_EIC_PER_BANK_NR);
165 
166 	return !!(readl_relaxed(base + reg) & BIT(SPRD_EIC_BIT(offset)));
167 }
168 
169 static int sprd_eic_request(struct gpio_chip *chip, unsigned int offset)
170 {
171 	sprd_eic_update(chip, offset, SPRD_EIC_DBNC_DMSK, 1);
172 	return 0;
173 }
174 
175 static void sprd_eic_free(struct gpio_chip *chip, unsigned int offset)
176 {
177 	sprd_eic_update(chip, offset, SPRD_EIC_DBNC_DMSK, 0);
178 }
179 
180 static int sprd_eic_get(struct gpio_chip *chip, unsigned int offset)
181 {
182 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
183 
184 	switch (sprd_eic->type) {
185 	case SPRD_EIC_DEBOUNCE:
186 		return sprd_eic_read(chip, offset, SPRD_EIC_DBNC_DATA);
187 	case SPRD_EIC_ASYNC:
188 		return sprd_eic_read(chip, offset, SPRD_EIC_ASYNC_DATA);
189 	case SPRD_EIC_SYNC:
190 		return sprd_eic_read(chip, offset, SPRD_EIC_SYNC_DATA);
191 	default:
192 		return -ENOTSUPP;
193 	}
194 }
195 
196 static int sprd_eic_direction_input(struct gpio_chip *chip, unsigned int offset)
197 {
198 	/* EICs are always input, nothing need to do here. */
199 	return 0;
200 }
201 
202 static void sprd_eic_set(struct gpio_chip *chip, unsigned int offset, int value)
203 {
204 	/* EICs are always input, nothing need to do here. */
205 }
206 
207 static int sprd_eic_set_debounce(struct gpio_chip *chip, unsigned int offset,
208 				 unsigned int debounce)
209 {
210 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
211 	void __iomem *base =
212 		sprd_eic_offset_base(sprd_eic, offset / SPRD_EIC_PER_BANK_NR);
213 	u32 reg = SPRD_EIC_DBNC_CTRL0 + SPRD_EIC_BIT(offset) * 0x4;
214 	u32 value = readl_relaxed(base + reg) & ~SPRD_EIC_DBNC_MASK;
215 
216 	value |= (debounce / 1000) & SPRD_EIC_DBNC_MASK;
217 	writel_relaxed(value, base + reg);
218 
219 	return 0;
220 }
221 
222 static int sprd_eic_set_config(struct gpio_chip *chip, unsigned int offset,
223 			       unsigned long config)
224 {
225 	unsigned long param = pinconf_to_config_param(config);
226 	u32 arg = pinconf_to_config_argument(config);
227 
228 	if (param == PIN_CONFIG_INPUT_DEBOUNCE)
229 		return sprd_eic_set_debounce(chip, offset, arg);
230 
231 	return -ENOTSUPP;
232 }
233 
234 static void sprd_eic_irq_mask(struct irq_data *data)
235 {
236 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
237 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
238 	u32 offset = irqd_to_hwirq(data);
239 
240 	switch (sprd_eic->type) {
241 	case SPRD_EIC_DEBOUNCE:
242 		sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IE, 0);
243 		sprd_eic_update(chip, offset, SPRD_EIC_DBNC_TRIG, 0);
244 		break;
245 	case SPRD_EIC_LATCH:
246 		sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTEN, 0);
247 		break;
248 	case SPRD_EIC_ASYNC:
249 		sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTIE, 0);
250 		break;
251 	case SPRD_EIC_SYNC:
252 		sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTIE, 0);
253 		break;
254 	default:
255 		dev_err(chip->parent, "Unsupported EIC type.\n");
256 	}
257 
258 	gpiochip_disable_irq(chip, offset);
259 }
260 
261 static void sprd_eic_irq_unmask(struct irq_data *data)
262 {
263 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
264 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
265 	u32 offset = irqd_to_hwirq(data);
266 
267 	gpiochip_enable_irq(chip, offset);
268 
269 	switch (sprd_eic->type) {
270 	case SPRD_EIC_DEBOUNCE:
271 		sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IE, 1);
272 		sprd_eic_update(chip, offset, SPRD_EIC_DBNC_TRIG, 1);
273 		break;
274 	case SPRD_EIC_LATCH:
275 		sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTEN, 1);
276 		break;
277 	case SPRD_EIC_ASYNC:
278 		sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTIE, 1);
279 		break;
280 	case SPRD_EIC_SYNC:
281 		sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTIE, 1);
282 		break;
283 	default:
284 		dev_err(chip->parent, "Unsupported EIC type.\n");
285 	}
286 }
287 
288 static void sprd_eic_irq_ack(struct irq_data *data)
289 {
290 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
291 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
292 	u32 offset = irqd_to_hwirq(data);
293 
294 	switch (sprd_eic->type) {
295 	case SPRD_EIC_DEBOUNCE:
296 		sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IC, 1);
297 		break;
298 	case SPRD_EIC_LATCH:
299 		sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTCLR, 1);
300 		break;
301 	case SPRD_EIC_ASYNC:
302 		sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTCLR, 1);
303 		break;
304 	case SPRD_EIC_SYNC:
305 		sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTCLR, 1);
306 		break;
307 	default:
308 		dev_err(chip->parent, "Unsupported EIC type.\n");
309 	}
310 }
311 
312 static int sprd_eic_irq_set_type(struct irq_data *data, unsigned int flow_type)
313 {
314 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
315 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
316 	u32 offset = irqd_to_hwirq(data);
317 	int state;
318 
319 	switch (sprd_eic->type) {
320 	case SPRD_EIC_DEBOUNCE:
321 		switch (flow_type) {
322 		case IRQ_TYPE_LEVEL_HIGH:
323 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IEV, 1);
324 			break;
325 		case IRQ_TYPE_LEVEL_LOW:
326 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IEV, 0);
327 			break;
328 		case IRQ_TYPE_EDGE_RISING:
329 		case IRQ_TYPE_EDGE_FALLING:
330 		case IRQ_TYPE_EDGE_BOTH:
331 			state = sprd_eic_get(chip, offset);
332 			if (state)
333 				sprd_eic_update(chip, offset,
334 						SPRD_EIC_DBNC_IEV, 0);
335 			else
336 				sprd_eic_update(chip, offset,
337 						SPRD_EIC_DBNC_IEV, 1);
338 			break;
339 		default:
340 			return -ENOTSUPP;
341 		}
342 
343 		irq_set_handler_locked(data, handle_level_irq);
344 		break;
345 	case SPRD_EIC_LATCH:
346 		switch (flow_type) {
347 		case IRQ_TYPE_LEVEL_HIGH:
348 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTPOL, 0);
349 			break;
350 		case IRQ_TYPE_LEVEL_LOW:
351 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTPOL, 1);
352 			break;
353 		case IRQ_TYPE_EDGE_RISING:
354 		case IRQ_TYPE_EDGE_FALLING:
355 		case IRQ_TYPE_EDGE_BOTH:
356 			state = sprd_eic_get(chip, offset);
357 			if (state)
358 				sprd_eic_update(chip, offset,
359 						SPRD_EIC_LATCH_INTPOL, 0);
360 			else
361 				sprd_eic_update(chip, offset,
362 						SPRD_EIC_LATCH_INTPOL, 1);
363 			break;
364 		default:
365 			return -ENOTSUPP;
366 		}
367 
368 		irq_set_handler_locked(data, handle_level_irq);
369 		break;
370 	case SPRD_EIC_ASYNC:
371 		switch (flow_type) {
372 		case IRQ_TYPE_EDGE_RISING:
373 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 0);
374 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 0);
375 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTPOL, 1);
376 			irq_set_handler_locked(data, handle_edge_irq);
377 			break;
378 		case IRQ_TYPE_EDGE_FALLING:
379 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 0);
380 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 0);
381 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTPOL, 0);
382 			irq_set_handler_locked(data, handle_edge_irq);
383 			break;
384 		case IRQ_TYPE_EDGE_BOTH:
385 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 0);
386 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 1);
387 			irq_set_handler_locked(data, handle_edge_irq);
388 			break;
389 		case IRQ_TYPE_LEVEL_HIGH:
390 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 0);
391 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 1);
392 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTPOL, 1);
393 			irq_set_handler_locked(data, handle_level_irq);
394 			break;
395 		case IRQ_TYPE_LEVEL_LOW:
396 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 0);
397 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 1);
398 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTPOL, 0);
399 			irq_set_handler_locked(data, handle_level_irq);
400 			break;
401 		default:
402 			return -ENOTSUPP;
403 		}
404 		break;
405 	case SPRD_EIC_SYNC:
406 		switch (flow_type) {
407 		case IRQ_TYPE_EDGE_RISING:
408 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 0);
409 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 0);
410 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTPOL, 1);
411 			irq_set_handler_locked(data, handle_edge_irq);
412 			break;
413 		case IRQ_TYPE_EDGE_FALLING:
414 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 0);
415 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 0);
416 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTPOL, 0);
417 			irq_set_handler_locked(data, handle_edge_irq);
418 			break;
419 		case IRQ_TYPE_EDGE_BOTH:
420 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 0);
421 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 1);
422 			irq_set_handler_locked(data, handle_edge_irq);
423 			break;
424 		case IRQ_TYPE_LEVEL_HIGH:
425 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 0);
426 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 1);
427 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTPOL, 1);
428 			irq_set_handler_locked(data, handle_level_irq);
429 			break;
430 		case IRQ_TYPE_LEVEL_LOW:
431 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 0);
432 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 1);
433 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTPOL, 0);
434 			irq_set_handler_locked(data, handle_level_irq);
435 			break;
436 		default:
437 			return -ENOTSUPP;
438 		}
439 		break;
440 	default:
441 		dev_err(chip->parent, "Unsupported EIC type.\n");
442 		return -ENOTSUPP;
443 	}
444 
445 	return 0;
446 }
447 
448 static void sprd_eic_toggle_trigger(struct gpio_chip *chip, unsigned int irq,
449 				    unsigned int offset)
450 {
451 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
452 	struct irq_data *data = irq_get_irq_data(irq);
453 	u32 trigger = irqd_get_trigger_type(data);
454 	int state, post_state;
455 
456 	/*
457 	 * The debounce EIC and latch EIC can only support level trigger, so we
458 	 * can toggle the level trigger to emulate the edge trigger.
459 	 */
460 	if ((sprd_eic->type != SPRD_EIC_DEBOUNCE &&
461 	     sprd_eic->type != SPRD_EIC_LATCH) ||
462 	    !(trigger & IRQ_TYPE_EDGE_BOTH))
463 		return;
464 
465 	sprd_eic_irq_mask(data);
466 	state = sprd_eic_get(chip, offset);
467 
468 retry:
469 	switch (sprd_eic->type) {
470 	case SPRD_EIC_DEBOUNCE:
471 		if (state)
472 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IEV, 0);
473 		else
474 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IEV, 1);
475 		break;
476 	case SPRD_EIC_LATCH:
477 		if (state)
478 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTPOL, 0);
479 		else
480 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTPOL, 1);
481 		break;
482 	default:
483 		sprd_eic_irq_unmask(data);
484 		return;
485 	}
486 
487 	post_state = sprd_eic_get(chip, offset);
488 	if (state != post_state) {
489 		dev_warn(chip->parent, "EIC level was changed.\n");
490 		state = post_state;
491 		goto retry;
492 	}
493 
494 	sprd_eic_irq_unmask(data);
495 }
496 
497 static int sprd_eic_match_chip_by_type(struct gpio_chip *chip, void *data)
498 {
499 	enum sprd_eic_type type = *(enum sprd_eic_type *)data;
500 
501 	return !strcmp(chip->label, sprd_eic_label_name[type]);
502 }
503 
504 static void sprd_eic_handle_one_type(struct gpio_chip *chip)
505 {
506 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
507 	u32 bank, n, girq;
508 
509 	for (bank = 0; bank * SPRD_EIC_PER_BANK_NR < chip->ngpio; bank++) {
510 		void __iomem *base = sprd_eic_offset_base(sprd_eic, bank);
511 		unsigned long reg;
512 
513 		switch (sprd_eic->type) {
514 		case SPRD_EIC_DEBOUNCE:
515 			reg = readl_relaxed(base + SPRD_EIC_DBNC_MIS) &
516 				SPRD_EIC_DATA_MASK;
517 			break;
518 		case SPRD_EIC_LATCH:
519 			reg = readl_relaxed(base + SPRD_EIC_LATCH_INTMSK) &
520 				SPRD_EIC_DATA_MASK;
521 			break;
522 		case SPRD_EIC_ASYNC:
523 			reg = readl_relaxed(base + SPRD_EIC_ASYNC_INTMSK) &
524 				SPRD_EIC_DATA_MASK;
525 			break;
526 		case SPRD_EIC_SYNC:
527 			reg = readl_relaxed(base + SPRD_EIC_SYNC_INTMSK) &
528 				SPRD_EIC_DATA_MASK;
529 			break;
530 		default:
531 			dev_err(chip->parent, "Unsupported EIC type.\n");
532 			return;
533 		}
534 
535 		for_each_set_bit(n, &reg, SPRD_EIC_PER_BANK_NR) {
536 			u32 offset = bank * SPRD_EIC_PER_BANK_NR + n;
537 
538 			girq = irq_find_mapping(chip->irq.domain, offset);
539 
540 			generic_handle_irq(girq);
541 			sprd_eic_toggle_trigger(chip, girq, offset);
542 		}
543 	}
544 }
545 
546 static void sprd_eic_irq_handler(struct irq_desc *desc)
547 {
548 	struct irq_chip *ic = irq_desc_get_chip(desc);
549 	struct gpio_chip *chip;
550 	enum sprd_eic_type type;
551 
552 	chained_irq_enter(ic, desc);
553 
554 	/*
555 	 * Since the digital-chip EIC 4 sub-modules (debounce, latch, async
556 	 * and sync) share one same interrupt line, we should iterate each
557 	 * EIC module to check if there are EIC interrupts were triggered.
558 	 */
559 	for (type = SPRD_EIC_DEBOUNCE; type < SPRD_EIC_MAX; type++) {
560 		chip = gpiochip_find(&type, sprd_eic_match_chip_by_type);
561 		if (!chip)
562 			continue;
563 
564 		sprd_eic_handle_one_type(chip);
565 	}
566 
567 	chained_irq_exit(ic, desc);
568 }
569 
570 static const struct irq_chip sprd_eic_irq = {
571 	.name		= "sprd-eic",
572 	.irq_ack	= sprd_eic_irq_ack,
573 	.irq_mask	= sprd_eic_irq_mask,
574 	.irq_unmask	= sprd_eic_irq_unmask,
575 	.irq_set_type	= sprd_eic_irq_set_type,
576 	.flags		= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_IMMUTABLE,
577 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
578 };
579 static int sprd_eic_probe(struct platform_device *pdev)
580 {
581 	const struct sprd_eic_variant_data *pdata;
582 	struct gpio_irq_chip *irq;
583 	struct sprd_eic *sprd_eic;
584 	struct resource *res;
585 	int ret, i;
586 
587 	pdata = of_device_get_match_data(&pdev->dev);
588 	if (!pdata) {
589 		dev_err(&pdev->dev, "No matching driver data found.\n");
590 		return -EINVAL;
591 	}
592 
593 	sprd_eic = devm_kzalloc(&pdev->dev, sizeof(*sprd_eic), GFP_KERNEL);
594 	if (!sprd_eic)
595 		return -ENOMEM;
596 
597 	spin_lock_init(&sprd_eic->lock);
598 	sprd_eic->type = pdata->type;
599 
600 	sprd_eic->irq = platform_get_irq(pdev, 0);
601 	if (sprd_eic->irq < 0)
602 		return sprd_eic->irq;
603 
604 	for (i = 0; i < SPRD_EIC_MAX_BANK; i++) {
605 		/*
606 		 * We can have maximum 3 banks EICs, and each EIC has
607 		 * its own base address. But some platform maybe only
608 		 * have one bank EIC, thus base[1] and base[2] can be
609 		 * optional.
610 		 */
611 		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
612 		if (!res)
613 			break;
614 
615 		sprd_eic->base[i] = devm_ioremap_resource(&pdev->dev, res);
616 		if (IS_ERR(sprd_eic->base[i]))
617 			return PTR_ERR(sprd_eic->base[i]);
618 	}
619 
620 	sprd_eic->chip.label = sprd_eic_label_name[sprd_eic->type];
621 	sprd_eic->chip.ngpio = pdata->num_eics;
622 	sprd_eic->chip.base = -1;
623 	sprd_eic->chip.parent = &pdev->dev;
624 	sprd_eic->chip.direction_input = sprd_eic_direction_input;
625 	switch (sprd_eic->type) {
626 	case SPRD_EIC_DEBOUNCE:
627 		sprd_eic->chip.request = sprd_eic_request;
628 		sprd_eic->chip.free = sprd_eic_free;
629 		sprd_eic->chip.set_config = sprd_eic_set_config;
630 		sprd_eic->chip.set = sprd_eic_set;
631 		fallthrough;
632 	case SPRD_EIC_ASYNC:
633 	case SPRD_EIC_SYNC:
634 		sprd_eic->chip.get = sprd_eic_get;
635 		break;
636 	case SPRD_EIC_LATCH:
637 	default:
638 		break;
639 	}
640 
641 	irq = &sprd_eic->chip.irq;
642 	gpio_irq_chip_set_chip(irq, &sprd_eic_irq);
643 	irq->handler = handle_bad_irq;
644 	irq->default_type = IRQ_TYPE_NONE;
645 	irq->parent_handler = sprd_eic_irq_handler;
646 	irq->parent_handler_data = sprd_eic;
647 	irq->num_parents = 1;
648 	irq->parents = &sprd_eic->irq;
649 
650 	ret = devm_gpiochip_add_data(&pdev->dev, &sprd_eic->chip, sprd_eic);
651 	if (ret < 0) {
652 		dev_err(&pdev->dev, "Could not register gpiochip %d.\n", ret);
653 		return ret;
654 	}
655 
656 	return 0;
657 }
658 
659 static const struct of_device_id sprd_eic_of_match[] = {
660 	{
661 		.compatible = "sprd,sc9860-eic-debounce",
662 		.data = &sc9860_eic_dbnc_data,
663 	},
664 	{
665 		.compatible = "sprd,sc9860-eic-latch",
666 		.data = &sc9860_eic_latch_data,
667 	},
668 	{
669 		.compatible = "sprd,sc9860-eic-async",
670 		.data = &sc9860_eic_async_data,
671 	},
672 	{
673 		.compatible = "sprd,sc9860-eic-sync",
674 		.data = &sc9860_eic_sync_data,
675 	},
676 	{
677 		/* end of list */
678 	}
679 };
680 MODULE_DEVICE_TABLE(of, sprd_eic_of_match);
681 
682 static struct platform_driver sprd_eic_driver = {
683 	.probe = sprd_eic_probe,
684 	.driver = {
685 		.name = "sprd-eic",
686 		.of_match_table	= sprd_eic_of_match,
687 	},
688 };
689 
690 module_platform_driver(sprd_eic_driver);
691 
692 MODULE_DESCRIPTION("Spreadtrum EIC driver");
693 MODULE_LICENSE("GPL v2");
694