xref: /openbmc/linux/drivers/gpio/gpio-eic-sprd.c (revision 177fe2a7)
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 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IC, 1);
325 			break;
326 		case IRQ_TYPE_LEVEL_LOW:
327 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IEV, 0);
328 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IC, 1);
329 			break;
330 		case IRQ_TYPE_EDGE_RISING:
331 		case IRQ_TYPE_EDGE_FALLING:
332 		case IRQ_TYPE_EDGE_BOTH:
333 			state = sprd_eic_get(chip, offset);
334 			if (state) {
335 				sprd_eic_update(chip, offset,
336 						SPRD_EIC_DBNC_IEV, 0);
337 				sprd_eic_update(chip, offset,
338 						SPRD_EIC_DBNC_IC, 1);
339 			} else {
340 				sprd_eic_update(chip, offset,
341 						SPRD_EIC_DBNC_IEV, 1);
342 				sprd_eic_update(chip, offset,
343 						SPRD_EIC_DBNC_IC, 1);
344 			}
345 			break;
346 		default:
347 			return -ENOTSUPP;
348 		}
349 
350 		irq_set_handler_locked(data, handle_level_irq);
351 		break;
352 	case SPRD_EIC_LATCH:
353 		switch (flow_type) {
354 		case IRQ_TYPE_LEVEL_HIGH:
355 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTPOL, 0);
356 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTCLR, 1);
357 			break;
358 		case IRQ_TYPE_LEVEL_LOW:
359 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTPOL, 1);
360 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTCLR, 1);
361 			break;
362 		case IRQ_TYPE_EDGE_RISING:
363 		case IRQ_TYPE_EDGE_FALLING:
364 		case IRQ_TYPE_EDGE_BOTH:
365 			state = sprd_eic_get(chip, offset);
366 			if (state) {
367 				sprd_eic_update(chip, offset,
368 						SPRD_EIC_LATCH_INTPOL, 0);
369 				sprd_eic_update(chip, offset,
370 						SPRD_EIC_LATCH_INTCLR, 1);
371 			} else {
372 				sprd_eic_update(chip, offset,
373 						SPRD_EIC_LATCH_INTPOL, 1);
374 				sprd_eic_update(chip, offset,
375 						SPRD_EIC_LATCH_INTCLR, 1);
376 			}
377 			break;
378 		default:
379 			return -ENOTSUPP;
380 		}
381 
382 		irq_set_handler_locked(data, handle_level_irq);
383 		break;
384 	case SPRD_EIC_ASYNC:
385 		switch (flow_type) {
386 		case IRQ_TYPE_EDGE_RISING:
387 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 0);
388 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 0);
389 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTPOL, 1);
390 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTCLR, 1);
391 			irq_set_handler_locked(data, handle_edge_irq);
392 			break;
393 		case IRQ_TYPE_EDGE_FALLING:
394 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 0);
395 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 0);
396 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTPOL, 0);
397 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTCLR, 1);
398 			irq_set_handler_locked(data, handle_edge_irq);
399 			break;
400 		case IRQ_TYPE_EDGE_BOTH:
401 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 0);
402 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 1);
403 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTCLR, 1);
404 			irq_set_handler_locked(data, handle_edge_irq);
405 			break;
406 		case IRQ_TYPE_LEVEL_HIGH:
407 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 0);
408 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 1);
409 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTPOL, 1);
410 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTCLR, 1);
411 			irq_set_handler_locked(data, handle_level_irq);
412 			break;
413 		case IRQ_TYPE_LEVEL_LOW:
414 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTBOTH, 0);
415 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTMODE, 1);
416 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTPOL, 0);
417 			sprd_eic_update(chip, offset, SPRD_EIC_ASYNC_INTCLR, 1);
418 			irq_set_handler_locked(data, handle_level_irq);
419 			break;
420 		default:
421 			return -ENOTSUPP;
422 		}
423 		break;
424 	case SPRD_EIC_SYNC:
425 		switch (flow_type) {
426 		case IRQ_TYPE_EDGE_RISING:
427 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 0);
428 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 0);
429 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTPOL, 1);
430 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTCLR, 1);
431 			irq_set_handler_locked(data, handle_edge_irq);
432 			break;
433 		case IRQ_TYPE_EDGE_FALLING:
434 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 0);
435 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 0);
436 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTPOL, 0);
437 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTCLR, 1);
438 			irq_set_handler_locked(data, handle_edge_irq);
439 			break;
440 		case IRQ_TYPE_EDGE_BOTH:
441 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 0);
442 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 1);
443 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTCLR, 1);
444 			irq_set_handler_locked(data, handle_edge_irq);
445 			break;
446 		case IRQ_TYPE_LEVEL_HIGH:
447 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 0);
448 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 1);
449 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTPOL, 1);
450 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTCLR, 1);
451 			irq_set_handler_locked(data, handle_level_irq);
452 			break;
453 		case IRQ_TYPE_LEVEL_LOW:
454 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTBOTH, 0);
455 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTMODE, 1);
456 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTPOL, 0);
457 			sprd_eic_update(chip, offset, SPRD_EIC_SYNC_INTCLR, 1);
458 			irq_set_handler_locked(data, handle_level_irq);
459 			break;
460 		default:
461 			return -ENOTSUPP;
462 		}
463 		break;
464 	default:
465 		dev_err(chip->parent, "Unsupported EIC type.\n");
466 		return -ENOTSUPP;
467 	}
468 
469 	return 0;
470 }
471 
472 static void sprd_eic_toggle_trigger(struct gpio_chip *chip, unsigned int irq,
473 				    unsigned int offset)
474 {
475 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
476 	struct irq_data *data = irq_get_irq_data(irq);
477 	u32 trigger = irqd_get_trigger_type(data);
478 	int state, post_state;
479 
480 	/*
481 	 * The debounce EIC and latch EIC can only support level trigger, so we
482 	 * can toggle the level trigger to emulate the edge trigger.
483 	 */
484 	if ((sprd_eic->type != SPRD_EIC_DEBOUNCE &&
485 	     sprd_eic->type != SPRD_EIC_LATCH) ||
486 	    !(trigger & IRQ_TYPE_EDGE_BOTH))
487 		return;
488 
489 	sprd_eic_irq_mask(data);
490 	state = sprd_eic_get(chip, offset);
491 
492 retry:
493 	switch (sprd_eic->type) {
494 	case SPRD_EIC_DEBOUNCE:
495 		if (state)
496 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IEV, 0);
497 		else
498 			sprd_eic_update(chip, offset, SPRD_EIC_DBNC_IEV, 1);
499 		break;
500 	case SPRD_EIC_LATCH:
501 		if (state)
502 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTPOL, 0);
503 		else
504 			sprd_eic_update(chip, offset, SPRD_EIC_LATCH_INTPOL, 1);
505 		break;
506 	default:
507 		sprd_eic_irq_unmask(data);
508 		return;
509 	}
510 
511 	post_state = sprd_eic_get(chip, offset);
512 	if (state != post_state) {
513 		dev_warn(chip->parent, "EIC level was changed.\n");
514 		state = post_state;
515 		goto retry;
516 	}
517 
518 	sprd_eic_irq_unmask(data);
519 }
520 
521 static int sprd_eic_match_chip_by_type(struct gpio_chip *chip, void *data)
522 {
523 	enum sprd_eic_type type = *(enum sprd_eic_type *)data;
524 
525 	return !strcmp(chip->label, sprd_eic_label_name[type]);
526 }
527 
528 static void sprd_eic_handle_one_type(struct gpio_chip *chip)
529 {
530 	struct sprd_eic *sprd_eic = gpiochip_get_data(chip);
531 	u32 bank, n, girq;
532 
533 	for (bank = 0; bank * SPRD_EIC_PER_BANK_NR < chip->ngpio; bank++) {
534 		void __iomem *base = sprd_eic_offset_base(sprd_eic, bank);
535 		unsigned long reg;
536 
537 		switch (sprd_eic->type) {
538 		case SPRD_EIC_DEBOUNCE:
539 			reg = readl_relaxed(base + SPRD_EIC_DBNC_MIS) &
540 				SPRD_EIC_DATA_MASK;
541 			break;
542 		case SPRD_EIC_LATCH:
543 			reg = readl_relaxed(base + SPRD_EIC_LATCH_INTMSK) &
544 				SPRD_EIC_DATA_MASK;
545 			break;
546 		case SPRD_EIC_ASYNC:
547 			reg = readl_relaxed(base + SPRD_EIC_ASYNC_INTMSK) &
548 				SPRD_EIC_DATA_MASK;
549 			break;
550 		case SPRD_EIC_SYNC:
551 			reg = readl_relaxed(base + SPRD_EIC_SYNC_INTMSK) &
552 				SPRD_EIC_DATA_MASK;
553 			break;
554 		default:
555 			dev_err(chip->parent, "Unsupported EIC type.\n");
556 			return;
557 		}
558 
559 		for_each_set_bit(n, &reg, SPRD_EIC_PER_BANK_NR) {
560 			u32 offset = bank * SPRD_EIC_PER_BANK_NR + n;
561 
562 			girq = irq_find_mapping(chip->irq.domain, offset);
563 
564 			generic_handle_irq(girq);
565 			sprd_eic_toggle_trigger(chip, girq, offset);
566 		}
567 	}
568 }
569 
570 static void sprd_eic_irq_handler(struct irq_desc *desc)
571 {
572 	struct irq_chip *ic = irq_desc_get_chip(desc);
573 	struct gpio_chip *chip;
574 	enum sprd_eic_type type;
575 
576 	chained_irq_enter(ic, desc);
577 
578 	/*
579 	 * Since the digital-chip EIC 4 sub-modules (debounce, latch, async
580 	 * and sync) share one same interrupt line, we should iterate each
581 	 * EIC module to check if there are EIC interrupts were triggered.
582 	 */
583 	for (type = SPRD_EIC_DEBOUNCE; type < SPRD_EIC_MAX; type++) {
584 		chip = gpiochip_find(&type, sprd_eic_match_chip_by_type);
585 		if (!chip)
586 			continue;
587 
588 		sprd_eic_handle_one_type(chip);
589 	}
590 
591 	chained_irq_exit(ic, desc);
592 }
593 
594 static const struct irq_chip sprd_eic_irq = {
595 	.name		= "sprd-eic",
596 	.irq_ack	= sprd_eic_irq_ack,
597 	.irq_mask	= sprd_eic_irq_mask,
598 	.irq_unmask	= sprd_eic_irq_unmask,
599 	.irq_set_type	= sprd_eic_irq_set_type,
600 	.flags		= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_IMMUTABLE,
601 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
602 };
603 static int sprd_eic_probe(struct platform_device *pdev)
604 {
605 	const struct sprd_eic_variant_data *pdata;
606 	struct gpio_irq_chip *irq;
607 	struct sprd_eic *sprd_eic;
608 	struct resource *res;
609 	int ret, i;
610 
611 	pdata = of_device_get_match_data(&pdev->dev);
612 	if (!pdata) {
613 		dev_err(&pdev->dev, "No matching driver data found.\n");
614 		return -EINVAL;
615 	}
616 
617 	sprd_eic = devm_kzalloc(&pdev->dev, sizeof(*sprd_eic), GFP_KERNEL);
618 	if (!sprd_eic)
619 		return -ENOMEM;
620 
621 	spin_lock_init(&sprd_eic->lock);
622 	sprd_eic->type = pdata->type;
623 
624 	sprd_eic->irq = platform_get_irq(pdev, 0);
625 	if (sprd_eic->irq < 0)
626 		return sprd_eic->irq;
627 
628 	for (i = 0; i < SPRD_EIC_MAX_BANK; i++) {
629 		/*
630 		 * We can have maximum 3 banks EICs, and each EIC has
631 		 * its own base address. But some platform maybe only
632 		 * have one bank EIC, thus base[1] and base[2] can be
633 		 * optional.
634 		 */
635 		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
636 		if (!res)
637 			break;
638 
639 		sprd_eic->base[i] = devm_ioremap_resource(&pdev->dev, res);
640 		if (IS_ERR(sprd_eic->base[i]))
641 			return PTR_ERR(sprd_eic->base[i]);
642 	}
643 
644 	sprd_eic->chip.label = sprd_eic_label_name[sprd_eic->type];
645 	sprd_eic->chip.ngpio = pdata->num_eics;
646 	sprd_eic->chip.base = -1;
647 	sprd_eic->chip.parent = &pdev->dev;
648 	sprd_eic->chip.direction_input = sprd_eic_direction_input;
649 	switch (sprd_eic->type) {
650 	case SPRD_EIC_DEBOUNCE:
651 		sprd_eic->chip.request = sprd_eic_request;
652 		sprd_eic->chip.free = sprd_eic_free;
653 		sprd_eic->chip.set_config = sprd_eic_set_config;
654 		sprd_eic->chip.set = sprd_eic_set;
655 		fallthrough;
656 	case SPRD_EIC_ASYNC:
657 	case SPRD_EIC_SYNC:
658 		sprd_eic->chip.get = sprd_eic_get;
659 		break;
660 	case SPRD_EIC_LATCH:
661 	default:
662 		break;
663 	}
664 
665 	irq = &sprd_eic->chip.irq;
666 	gpio_irq_chip_set_chip(irq, &sprd_eic_irq);
667 	irq->handler = handle_bad_irq;
668 	irq->default_type = IRQ_TYPE_NONE;
669 	irq->parent_handler = sprd_eic_irq_handler;
670 	irq->parent_handler_data = sprd_eic;
671 	irq->num_parents = 1;
672 	irq->parents = &sprd_eic->irq;
673 
674 	ret = devm_gpiochip_add_data(&pdev->dev, &sprd_eic->chip, sprd_eic);
675 	if (ret < 0) {
676 		dev_err(&pdev->dev, "Could not register gpiochip %d.\n", ret);
677 		return ret;
678 	}
679 
680 	return 0;
681 }
682 
683 static const struct of_device_id sprd_eic_of_match[] = {
684 	{
685 		.compatible = "sprd,sc9860-eic-debounce",
686 		.data = &sc9860_eic_dbnc_data,
687 	},
688 	{
689 		.compatible = "sprd,sc9860-eic-latch",
690 		.data = &sc9860_eic_latch_data,
691 	},
692 	{
693 		.compatible = "sprd,sc9860-eic-async",
694 		.data = &sc9860_eic_async_data,
695 	},
696 	{
697 		.compatible = "sprd,sc9860-eic-sync",
698 		.data = &sc9860_eic_sync_data,
699 	},
700 	{
701 		/* end of list */
702 	}
703 };
704 MODULE_DEVICE_TABLE(of, sprd_eic_of_match);
705 
706 static struct platform_driver sprd_eic_driver = {
707 	.probe = sprd_eic_probe,
708 	.driver = {
709 		.name = "sprd-eic",
710 		.of_match_table	= sprd_eic_of_match,
711 	},
712 };
713 
714 module_platform_driver(sprd_eic_driver);
715 
716 MODULE_DESCRIPTION("Spreadtrum EIC driver");
717 MODULE_LICENSE("GPL v2");
718