xref: /openbmc/linux/drivers/pinctrl/pinctrl-amd.c (revision 8bdc2a19)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * GPIO driver for AMD
4  *
5  * Copyright (c) 2014,2015 AMD Corporation.
6  * Authors: Ken Xue <Ken.Xue@amd.com>
7  *      Wu, Jeff <Jeff.Wu@amd.com>
8  *
9  * Contact Information: Nehal Shah <Nehal-bakulchandra.Shah@amd.com>
10  *			Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
11  */
12 
13 #include <linux/err.h>
14 #include <linux/bug.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/spinlock.h>
18 #include <linux/compiler.h>
19 #include <linux/types.h>
20 #include <linux/errno.h>
21 #include <linux/log2.h>
22 #include <linux/io.h>
23 #include <linux/gpio/driver.h>
24 #include <linux/slab.h>
25 #include <linux/platform_device.h>
26 #include <linux/mutex.h>
27 #include <linux/acpi.h>
28 #include <linux/seq_file.h>
29 #include <linux/interrupt.h>
30 #include <linux/list.h>
31 #include <linux/bitops.h>
32 #include <linux/pinctrl/pinconf.h>
33 #include <linux/pinctrl/pinconf-generic.h>
34 
35 #include "core.h"
36 #include "pinctrl-utils.h"
37 #include "pinctrl-amd.h"
38 
39 static int amd_gpio_get_direction(struct gpio_chip *gc, unsigned offset)
40 {
41 	unsigned long flags;
42 	u32 pin_reg;
43 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
44 
45 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
46 	pin_reg = readl(gpio_dev->base + offset * 4);
47 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
48 
49 	if (pin_reg & BIT(OUTPUT_ENABLE_OFF))
50 		return GPIO_LINE_DIRECTION_OUT;
51 
52 	return GPIO_LINE_DIRECTION_IN;
53 }
54 
55 static int amd_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
56 {
57 	unsigned long flags;
58 	u32 pin_reg;
59 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
60 
61 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
62 	pin_reg = readl(gpio_dev->base + offset * 4);
63 	pin_reg &= ~BIT(OUTPUT_ENABLE_OFF);
64 	writel(pin_reg, gpio_dev->base + offset * 4);
65 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
66 
67 	return 0;
68 }
69 
70 static int amd_gpio_direction_output(struct gpio_chip *gc, unsigned offset,
71 		int value)
72 {
73 	u32 pin_reg;
74 	unsigned long flags;
75 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
76 
77 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
78 	pin_reg = readl(gpio_dev->base + offset * 4);
79 	pin_reg |= BIT(OUTPUT_ENABLE_OFF);
80 	if (value)
81 		pin_reg |= BIT(OUTPUT_VALUE_OFF);
82 	else
83 		pin_reg &= ~BIT(OUTPUT_VALUE_OFF);
84 	writel(pin_reg, gpio_dev->base + offset * 4);
85 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
86 
87 	return 0;
88 }
89 
90 static int amd_gpio_get_value(struct gpio_chip *gc, unsigned offset)
91 {
92 	u32 pin_reg;
93 	unsigned long flags;
94 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
95 
96 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
97 	pin_reg = readl(gpio_dev->base + offset * 4);
98 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
99 
100 	return !!(pin_reg & BIT(PIN_STS_OFF));
101 }
102 
103 static void amd_gpio_set_value(struct gpio_chip *gc, unsigned offset, int value)
104 {
105 	u32 pin_reg;
106 	unsigned long flags;
107 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
108 
109 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
110 	pin_reg = readl(gpio_dev->base + offset * 4);
111 	if (value)
112 		pin_reg |= BIT(OUTPUT_VALUE_OFF);
113 	else
114 		pin_reg &= ~BIT(OUTPUT_VALUE_OFF);
115 	writel(pin_reg, gpio_dev->base + offset * 4);
116 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
117 }
118 
119 static int amd_gpio_set_debounce(struct gpio_chip *gc, unsigned offset,
120 		unsigned debounce)
121 {
122 	u32 time;
123 	u32 pin_reg;
124 	int ret = 0;
125 	unsigned long flags;
126 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
127 
128 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
129 	pin_reg = readl(gpio_dev->base + offset * 4);
130 
131 	if (debounce) {
132 		pin_reg |= DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF;
133 		pin_reg &= ~DB_TMR_OUT_MASK;
134 		/*
135 		Debounce	Debounce	Timer	Max
136 		TmrLarge	TmrOutUnit	Unit	Debounce
137 							Time
138 		0	0	61 usec (2 RtcClk)	976 usec
139 		0	1	244 usec (8 RtcClk)	3.9 msec
140 		1	0	15.6 msec (512 RtcClk)	250 msec
141 		1	1	62.5 msec (2048 RtcClk)	1 sec
142 		*/
143 
144 		if (debounce < 61) {
145 			pin_reg |= 1;
146 			pin_reg &= ~BIT(DB_TMR_OUT_UNIT_OFF);
147 			pin_reg &= ~BIT(DB_TMR_LARGE_OFF);
148 		} else if (debounce < 976) {
149 			time = debounce / 61;
150 			pin_reg |= time & DB_TMR_OUT_MASK;
151 			pin_reg &= ~BIT(DB_TMR_OUT_UNIT_OFF);
152 			pin_reg &= ~BIT(DB_TMR_LARGE_OFF);
153 		} else if (debounce < 3900) {
154 			time = debounce / 244;
155 			pin_reg |= time & DB_TMR_OUT_MASK;
156 			pin_reg |= BIT(DB_TMR_OUT_UNIT_OFF);
157 			pin_reg &= ~BIT(DB_TMR_LARGE_OFF);
158 		} else if (debounce < 250000) {
159 			time = debounce / 15625;
160 			pin_reg |= time & DB_TMR_OUT_MASK;
161 			pin_reg &= ~BIT(DB_TMR_OUT_UNIT_OFF);
162 			pin_reg |= BIT(DB_TMR_LARGE_OFF);
163 		} else if (debounce < 1000000) {
164 			time = debounce / 62500;
165 			pin_reg |= time & DB_TMR_OUT_MASK;
166 			pin_reg |= BIT(DB_TMR_OUT_UNIT_OFF);
167 			pin_reg |= BIT(DB_TMR_LARGE_OFF);
168 		} else {
169 			pin_reg &= ~(DB_CNTRl_MASK << DB_CNTRL_OFF);
170 			ret = -EINVAL;
171 		}
172 	} else {
173 		pin_reg &= ~BIT(DB_TMR_OUT_UNIT_OFF);
174 		pin_reg &= ~BIT(DB_TMR_LARGE_OFF);
175 		pin_reg &= ~DB_TMR_OUT_MASK;
176 		pin_reg &= ~(DB_CNTRl_MASK << DB_CNTRL_OFF);
177 	}
178 	writel(pin_reg, gpio_dev->base + offset * 4);
179 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
180 
181 	return ret;
182 }
183 
184 static int amd_gpio_set_config(struct gpio_chip *gc, unsigned offset,
185 			       unsigned long config)
186 {
187 	u32 debounce;
188 
189 	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
190 		return -ENOTSUPP;
191 
192 	debounce = pinconf_to_config_argument(config);
193 	return amd_gpio_set_debounce(gc, offset, debounce);
194 }
195 
196 #ifdef CONFIG_DEBUG_FS
197 static void amd_gpio_dbg_show(struct seq_file *s, struct gpio_chip *gc)
198 {
199 	u32 pin_reg;
200 	u32 db_cntrl;
201 	unsigned long flags;
202 	unsigned int bank, i, pin_num;
203 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
204 
205 	bool tmr_out_unit;
206 	unsigned int time;
207 	unsigned int unit;
208 	bool tmr_large;
209 
210 	char *level_trig;
211 	char *active_level;
212 	char *interrupt_enable;
213 	char *interrupt_mask;
214 	char *wake_cntrl0;
215 	char *wake_cntrl1;
216 	char *wake_cntrl2;
217 	char *pin_sts;
218 	char *pull_up_sel;
219 	char *pull_up_enable;
220 	char *pull_down_enable;
221 	char *output_value;
222 	char *output_enable;
223 	char debounce_value[40];
224 	char *debounce_enable;
225 
226 	for (bank = 0; bank < gpio_dev->hwbank_num; bank++) {
227 		seq_printf(s, "GPIO bank%d\t", bank);
228 
229 		switch (bank) {
230 		case 0:
231 			i = 0;
232 			pin_num = AMD_GPIO_PINS_BANK0;
233 			break;
234 		case 1:
235 			i = 64;
236 			pin_num = AMD_GPIO_PINS_BANK1 + i;
237 			break;
238 		case 2:
239 			i = 128;
240 			pin_num = AMD_GPIO_PINS_BANK2 + i;
241 			break;
242 		case 3:
243 			i = 192;
244 			pin_num = AMD_GPIO_PINS_BANK3 + i;
245 			break;
246 		default:
247 			/* Illegal bank number, ignore */
248 			continue;
249 		}
250 		for (; i < pin_num; i++) {
251 			seq_printf(s, "pin%d\t", i);
252 			raw_spin_lock_irqsave(&gpio_dev->lock, flags);
253 			pin_reg = readl(gpio_dev->base + i * 4);
254 			raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
255 
256 			if (pin_reg & BIT(INTERRUPT_ENABLE_OFF)) {
257 				u8 level = (pin_reg >> ACTIVE_LEVEL_OFF) &
258 						ACTIVE_LEVEL_MASK;
259 				interrupt_enable = "interrupt is enabled|";
260 
261 				if (level == ACTIVE_LEVEL_HIGH)
262 					active_level = "Active high|";
263 				else if (level == ACTIVE_LEVEL_LOW)
264 					active_level = "Active low|";
265 				else if (!(pin_reg & BIT(LEVEL_TRIG_OFF)) &&
266 					 level == ACTIVE_LEVEL_BOTH)
267 					active_level = "Active on both|";
268 				else
269 					active_level = "Unknown Active level|";
270 
271 				if (pin_reg & BIT(LEVEL_TRIG_OFF))
272 					level_trig = "Level trigger|";
273 				else
274 					level_trig = "Edge trigger|";
275 
276 			} else {
277 				interrupt_enable =
278 					"interrupt is disabled|";
279 				active_level = " ";
280 				level_trig = " ";
281 			}
282 
283 			if (pin_reg & BIT(INTERRUPT_MASK_OFF))
284 				interrupt_mask =
285 					"interrupt is unmasked|";
286 			else
287 				interrupt_mask =
288 					"interrupt is masked|";
289 
290 			if (pin_reg & BIT(WAKE_CNTRL_OFF_S0I3))
291 				wake_cntrl0 = "enable wakeup in S0i3 state|";
292 			else
293 				wake_cntrl0 = "disable wakeup in S0i3 state|";
294 
295 			if (pin_reg & BIT(WAKE_CNTRL_OFF_S3))
296 				wake_cntrl1 = "enable wakeup in S3 state|";
297 			else
298 				wake_cntrl1 = "disable wakeup in S3 state|";
299 
300 			if (pin_reg & BIT(WAKE_CNTRL_OFF_S4))
301 				wake_cntrl2 = "enable wakeup in S4/S5 state|";
302 			else
303 				wake_cntrl2 = "disable wakeup in S4/S5 state|";
304 
305 			if (pin_reg & BIT(PULL_UP_ENABLE_OFF)) {
306 				pull_up_enable = "pull-up is enabled|";
307 				if (pin_reg & BIT(PULL_UP_SEL_OFF))
308 					pull_up_sel = "8k pull-up|";
309 				else
310 					pull_up_sel = "4k pull-up|";
311 			} else {
312 				pull_up_enable = "pull-up is disabled|";
313 				pull_up_sel = " ";
314 			}
315 
316 			if (pin_reg & BIT(PULL_DOWN_ENABLE_OFF))
317 				pull_down_enable = "pull-down is enabled|";
318 			else
319 				pull_down_enable = "Pull-down is disabled|";
320 
321 			if (pin_reg & BIT(OUTPUT_ENABLE_OFF)) {
322 				pin_sts = " ";
323 				output_enable = "output is enabled|";
324 				if (pin_reg & BIT(OUTPUT_VALUE_OFF))
325 					output_value = "output is high|";
326 				else
327 					output_value = "output is low|";
328 			} else {
329 				output_enable = "output is disabled|";
330 				output_value = " ";
331 
332 				if (pin_reg & BIT(PIN_STS_OFF))
333 					pin_sts = "input is high|";
334 				else
335 					pin_sts = "input is low|";
336 			}
337 
338 			db_cntrl = (DB_CNTRl_MASK << DB_CNTRL_OFF) & pin_reg;
339 			if (db_cntrl) {
340 				tmr_out_unit = pin_reg & BIT(DB_TMR_OUT_UNIT_OFF);
341 				tmr_large = pin_reg & BIT(DB_TMR_LARGE_OFF);
342 				time = pin_reg & DB_TMR_OUT_MASK;
343 				if (tmr_large) {
344 					if (tmr_out_unit)
345 						unit = 62500;
346 					else
347 						unit = 15625;
348 				} else {
349 					if (tmr_out_unit)
350 						unit = 244;
351 					else
352 						unit = 61;
353 				}
354 				if ((DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF) == db_cntrl)
355 					debounce_enable = "debouncing filter (high and low) enabled|";
356 				else if ((DB_TYPE_PRESERVE_LOW_GLITCH << DB_CNTRL_OFF) == db_cntrl)
357 					debounce_enable = "debouncing filter (low) enabled|";
358 				else
359 					debounce_enable = "debouncing filter (high) enabled|";
360 
361 				snprintf(debounce_value, sizeof(debounce_value),
362 					 "debouncing timeout is %u (us)|", time * unit);
363 			} else {
364 				debounce_enable = "debouncing filter disabled|";
365 				snprintf(debounce_value, sizeof(debounce_value), " ");
366 			}
367 
368 			seq_printf(s, "%s %s %s %s %s %s\n"
369 				" %s %s %s %s %s %s %s %s %s 0x%x\n",
370 				level_trig, active_level, interrupt_enable,
371 				interrupt_mask, wake_cntrl0, wake_cntrl1,
372 				wake_cntrl2, pin_sts, pull_up_sel,
373 				pull_up_enable, pull_down_enable,
374 				output_value, output_enable,
375 				debounce_enable, debounce_value, pin_reg);
376 		}
377 	}
378 }
379 #else
380 #define amd_gpio_dbg_show NULL
381 #endif
382 
383 static void amd_gpio_irq_enable(struct irq_data *d)
384 {
385 	u32 pin_reg;
386 	unsigned long flags;
387 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
388 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
389 
390 	gpiochip_enable_irq(gc, d->hwirq);
391 
392 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
393 	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
394 	pin_reg |= BIT(INTERRUPT_ENABLE_OFF);
395 	pin_reg |= BIT(INTERRUPT_MASK_OFF);
396 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
397 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
398 }
399 
400 static void amd_gpio_irq_disable(struct irq_data *d)
401 {
402 	u32 pin_reg;
403 	unsigned long flags;
404 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
405 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
406 
407 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
408 	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
409 	pin_reg &= ~BIT(INTERRUPT_ENABLE_OFF);
410 	pin_reg &= ~BIT(INTERRUPT_MASK_OFF);
411 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
412 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
413 
414 	gpiochip_disable_irq(gc, d->hwirq);
415 }
416 
417 static void amd_gpio_irq_mask(struct irq_data *d)
418 {
419 	u32 pin_reg;
420 	unsigned long flags;
421 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
422 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
423 
424 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
425 	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
426 	pin_reg &= ~BIT(INTERRUPT_MASK_OFF);
427 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
428 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
429 }
430 
431 static void amd_gpio_irq_unmask(struct irq_data *d)
432 {
433 	u32 pin_reg;
434 	unsigned long flags;
435 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
436 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
437 
438 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
439 	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
440 	pin_reg |= BIT(INTERRUPT_MASK_OFF);
441 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
442 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
443 }
444 
445 static int amd_gpio_irq_set_wake(struct irq_data *d, unsigned int on)
446 {
447 	u32 pin_reg;
448 	unsigned long flags;
449 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
450 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
451 	u32 wake_mask = BIT(WAKE_CNTRL_OFF_S0I3) | BIT(WAKE_CNTRL_OFF_S3);
452 	int err;
453 
454 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
455 	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
456 
457 	if (on)
458 		pin_reg |= wake_mask;
459 	else
460 		pin_reg &= ~wake_mask;
461 
462 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
463 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
464 
465 	if (on)
466 		err = enable_irq_wake(gpio_dev->irq);
467 	else
468 		err = disable_irq_wake(gpio_dev->irq);
469 
470 	if (err)
471 		dev_err(&gpio_dev->pdev->dev, "failed to %s wake-up interrupt\n",
472 			on ? "enable" : "disable");
473 
474 	return 0;
475 }
476 
477 static void amd_gpio_irq_eoi(struct irq_data *d)
478 {
479 	u32 reg;
480 	unsigned long flags;
481 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
482 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
483 
484 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
485 	reg = readl(gpio_dev->base + WAKE_INT_MASTER_REG);
486 	reg |= EOI_MASK;
487 	writel(reg, gpio_dev->base + WAKE_INT_MASTER_REG);
488 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
489 }
490 
491 static int amd_gpio_irq_set_type(struct irq_data *d, unsigned int type)
492 {
493 	int ret = 0;
494 	u32 pin_reg, pin_reg_irq_en, mask;
495 	unsigned long flags;
496 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
497 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
498 
499 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
500 	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
501 
502 	switch (type & IRQ_TYPE_SENSE_MASK) {
503 	case IRQ_TYPE_EDGE_RISING:
504 		pin_reg &= ~BIT(LEVEL_TRIG_OFF);
505 		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
506 		pin_reg |= ACTIVE_HIGH << ACTIVE_LEVEL_OFF;
507 		irq_set_handler_locked(d, handle_edge_irq);
508 		break;
509 
510 	case IRQ_TYPE_EDGE_FALLING:
511 		pin_reg &= ~BIT(LEVEL_TRIG_OFF);
512 		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
513 		pin_reg |= ACTIVE_LOW << ACTIVE_LEVEL_OFF;
514 		irq_set_handler_locked(d, handle_edge_irq);
515 		break;
516 
517 	case IRQ_TYPE_EDGE_BOTH:
518 		pin_reg &= ~BIT(LEVEL_TRIG_OFF);
519 		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
520 		pin_reg |= BOTH_EADGE << ACTIVE_LEVEL_OFF;
521 		irq_set_handler_locked(d, handle_edge_irq);
522 		break;
523 
524 	case IRQ_TYPE_LEVEL_HIGH:
525 		pin_reg |= LEVEL_TRIGGER << LEVEL_TRIG_OFF;
526 		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
527 		pin_reg |= ACTIVE_HIGH << ACTIVE_LEVEL_OFF;
528 		irq_set_handler_locked(d, handle_level_irq);
529 		break;
530 
531 	case IRQ_TYPE_LEVEL_LOW:
532 		pin_reg |= LEVEL_TRIGGER << LEVEL_TRIG_OFF;
533 		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
534 		pin_reg |= ACTIVE_LOW << ACTIVE_LEVEL_OFF;
535 		irq_set_handler_locked(d, handle_level_irq);
536 		break;
537 
538 	case IRQ_TYPE_NONE:
539 		break;
540 
541 	default:
542 		dev_err(&gpio_dev->pdev->dev, "Invalid type value\n");
543 		ret = -EINVAL;
544 	}
545 
546 	pin_reg |= CLR_INTR_STAT << INTERRUPT_STS_OFF;
547 	/*
548 	 * If WAKE_INT_MASTER_REG.MaskStsEn is set, a software write to the
549 	 * debounce registers of any GPIO will block wake/interrupt status
550 	 * generation for *all* GPIOs for a length of time that depends on
551 	 * WAKE_INT_MASTER_REG.MaskStsLength[11:0].  During this period the
552 	 * INTERRUPT_ENABLE bit will read as 0.
553 	 *
554 	 * We temporarily enable irq for the GPIO whose configuration is
555 	 * changing, and then wait for it to read back as 1 to know when
556 	 * debounce has settled and then disable the irq again.
557 	 * We do this polling with the spinlock held to ensure other GPIO
558 	 * access routines do not read an incorrect value for the irq enable
559 	 * bit of other GPIOs.  We keep the GPIO masked while polling to avoid
560 	 * spurious irqs, and disable the irq again after polling.
561 	 */
562 	mask = BIT(INTERRUPT_ENABLE_OFF);
563 	pin_reg_irq_en = pin_reg;
564 	pin_reg_irq_en |= mask;
565 	pin_reg_irq_en &= ~BIT(INTERRUPT_MASK_OFF);
566 	writel(pin_reg_irq_en, gpio_dev->base + (d->hwirq)*4);
567 	while ((readl(gpio_dev->base + (d->hwirq)*4) & mask) != mask)
568 		continue;
569 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
570 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
571 
572 	return ret;
573 }
574 
575 static void amd_irq_ack(struct irq_data *d)
576 {
577 	/*
578 	 * based on HW design,there is no need to ack HW
579 	 * before handle current irq. But this routine is
580 	 * necessary for handle_edge_irq
581 	*/
582 }
583 
584 static const struct irq_chip amd_gpio_irqchip = {
585 	.name         = "amd_gpio",
586 	.irq_ack      = amd_irq_ack,
587 	.irq_enable   = amd_gpio_irq_enable,
588 	.irq_disable  = amd_gpio_irq_disable,
589 	.irq_mask     = amd_gpio_irq_mask,
590 	.irq_unmask   = amd_gpio_irq_unmask,
591 	.irq_set_wake = amd_gpio_irq_set_wake,
592 	.irq_eoi      = amd_gpio_irq_eoi,
593 	.irq_set_type = amd_gpio_irq_set_type,
594 	/*
595 	 * We need to set IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND so that a wake event
596 	 * also generates an IRQ. We need the IRQ so the irq_handler can clear
597 	 * the wake event. Otherwise the wake event will never clear and
598 	 * prevent the system from suspending.
599 	 */
600 	.flags        = IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND | IRQCHIP_IMMUTABLE,
601 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
602 };
603 
604 #define PIN_IRQ_PENDING	(BIT(INTERRUPT_STS_OFF) | BIT(WAKE_STS_OFF))
605 
606 static bool do_amd_gpio_irq_handler(int irq, void *dev_id)
607 {
608 	struct amd_gpio *gpio_dev = dev_id;
609 	struct gpio_chip *gc = &gpio_dev->gc;
610 	unsigned int i, irqnr;
611 	unsigned long flags;
612 	u32 __iomem *regs;
613 	bool ret = false;
614 	u32  regval;
615 	u64 status, mask;
616 
617 	/* Read the wake status */
618 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
619 	status = readl(gpio_dev->base + WAKE_INT_STATUS_REG1);
620 	status <<= 32;
621 	status |= readl(gpio_dev->base + WAKE_INT_STATUS_REG0);
622 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
623 
624 	/* Bit 0-45 contain the relevant status bits */
625 	status &= (1ULL << 46) - 1;
626 	regs = gpio_dev->base;
627 	for (mask = 1, irqnr = 0; status; mask <<= 1, regs += 4, irqnr += 4) {
628 		if (!(status & mask))
629 			continue;
630 		status &= ~mask;
631 
632 		/* Each status bit covers four pins */
633 		for (i = 0; i < 4; i++) {
634 			regval = readl(regs + i);
635 			/* caused wake on resume context for shared IRQ */
636 			if (irq < 0 && (regval & BIT(WAKE_STS_OFF))) {
637 				dev_dbg(&gpio_dev->pdev->dev,
638 					"Waking due to GPIO %d: 0x%x",
639 					irqnr + i, regval);
640 				return true;
641 			}
642 
643 			if (!(regval & PIN_IRQ_PENDING) ||
644 			    !(regval & BIT(INTERRUPT_MASK_OFF)))
645 				continue;
646 			generic_handle_domain_irq(gc->irq.domain, irqnr + i);
647 
648 			/* Clear interrupt.
649 			 * We must read the pin register again, in case the
650 			 * value was changed while executing
651 			 * generic_handle_domain_irq() above.
652 			 * If we didn't find a mapping for the interrupt,
653 			 * disable it in order to avoid a system hang caused
654 			 * by an interrupt storm.
655 			 */
656 			raw_spin_lock_irqsave(&gpio_dev->lock, flags);
657 			regval = readl(regs + i);
658 			if (irq == 0) {
659 				regval &= ~BIT(INTERRUPT_ENABLE_OFF);
660 				dev_dbg(&gpio_dev->pdev->dev,
661 					"Disabling spurious GPIO IRQ %d\n",
662 					irqnr + i);
663 			}
664 			writel(regval, regs + i);
665 			raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
666 			ret = true;
667 		}
668 	}
669 	/* did not cause wake on resume context for shared IRQ */
670 	if (irq < 0)
671 		return false;
672 
673 	/* Signal EOI to the GPIO unit */
674 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
675 	regval = readl(gpio_dev->base + WAKE_INT_MASTER_REG);
676 	regval |= EOI_MASK;
677 	writel(regval, gpio_dev->base + WAKE_INT_MASTER_REG);
678 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
679 
680 	return ret;
681 }
682 
683 static irqreturn_t amd_gpio_irq_handler(int irq, void *dev_id)
684 {
685 	return IRQ_RETVAL(do_amd_gpio_irq_handler(irq, dev_id));
686 }
687 
688 static bool __maybe_unused amd_gpio_check_wake(void *dev_id)
689 {
690 	return do_amd_gpio_irq_handler(-1, dev_id);
691 }
692 
693 static int amd_get_groups_count(struct pinctrl_dev *pctldev)
694 {
695 	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);
696 
697 	return gpio_dev->ngroups;
698 }
699 
700 static const char *amd_get_group_name(struct pinctrl_dev *pctldev,
701 				      unsigned group)
702 {
703 	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);
704 
705 	return gpio_dev->groups[group].name;
706 }
707 
708 static int amd_get_group_pins(struct pinctrl_dev *pctldev,
709 			      unsigned group,
710 			      const unsigned **pins,
711 			      unsigned *num_pins)
712 {
713 	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);
714 
715 	*pins = gpio_dev->groups[group].pins;
716 	*num_pins = gpio_dev->groups[group].npins;
717 	return 0;
718 }
719 
720 static const struct pinctrl_ops amd_pinctrl_ops = {
721 	.get_groups_count	= amd_get_groups_count,
722 	.get_group_name		= amd_get_group_name,
723 	.get_group_pins		= amd_get_group_pins,
724 #ifdef CONFIG_OF
725 	.dt_node_to_map		= pinconf_generic_dt_node_to_map_group,
726 	.dt_free_map		= pinctrl_utils_free_map,
727 #endif
728 };
729 
730 static int amd_pinconf_get(struct pinctrl_dev *pctldev,
731 			  unsigned int pin,
732 			  unsigned long *config)
733 {
734 	u32 pin_reg;
735 	unsigned arg;
736 	unsigned long flags;
737 	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);
738 	enum pin_config_param param = pinconf_to_config_param(*config);
739 
740 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
741 	pin_reg = readl(gpio_dev->base + pin*4);
742 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
743 	switch (param) {
744 	case PIN_CONFIG_INPUT_DEBOUNCE:
745 		arg = pin_reg & DB_TMR_OUT_MASK;
746 		break;
747 
748 	case PIN_CONFIG_BIAS_PULL_DOWN:
749 		arg = (pin_reg >> PULL_DOWN_ENABLE_OFF) & BIT(0);
750 		break;
751 
752 	case PIN_CONFIG_BIAS_PULL_UP:
753 		arg = (pin_reg >> PULL_UP_SEL_OFF) & (BIT(0) | BIT(1));
754 		break;
755 
756 	case PIN_CONFIG_DRIVE_STRENGTH:
757 		arg = (pin_reg >> DRV_STRENGTH_SEL_OFF) & DRV_STRENGTH_SEL_MASK;
758 		break;
759 
760 	default:
761 		dev_err(&gpio_dev->pdev->dev, "Invalid config param %04x\n",
762 			param);
763 		return -ENOTSUPP;
764 	}
765 
766 	*config = pinconf_to_config_packed(param, arg);
767 
768 	return 0;
769 }
770 
771 static int amd_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
772 				unsigned long *configs, unsigned num_configs)
773 {
774 	int i;
775 	u32 arg;
776 	int ret = 0;
777 	u32 pin_reg;
778 	unsigned long flags;
779 	enum pin_config_param param;
780 	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);
781 
782 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
783 	for (i = 0; i < num_configs; i++) {
784 		param = pinconf_to_config_param(configs[i]);
785 		arg = pinconf_to_config_argument(configs[i]);
786 		pin_reg = readl(gpio_dev->base + pin*4);
787 
788 		switch (param) {
789 		case PIN_CONFIG_INPUT_DEBOUNCE:
790 			pin_reg &= ~DB_TMR_OUT_MASK;
791 			pin_reg |= arg & DB_TMR_OUT_MASK;
792 			break;
793 
794 		case PIN_CONFIG_BIAS_PULL_DOWN:
795 			pin_reg &= ~BIT(PULL_DOWN_ENABLE_OFF);
796 			pin_reg |= (arg & BIT(0)) << PULL_DOWN_ENABLE_OFF;
797 			break;
798 
799 		case PIN_CONFIG_BIAS_PULL_UP:
800 			pin_reg &= ~BIT(PULL_UP_SEL_OFF);
801 			pin_reg |= (arg & BIT(0)) << PULL_UP_SEL_OFF;
802 			pin_reg &= ~BIT(PULL_UP_ENABLE_OFF);
803 			pin_reg |= ((arg>>1) & BIT(0)) << PULL_UP_ENABLE_OFF;
804 			break;
805 
806 		case PIN_CONFIG_DRIVE_STRENGTH:
807 			pin_reg &= ~(DRV_STRENGTH_SEL_MASK
808 					<< DRV_STRENGTH_SEL_OFF);
809 			pin_reg |= (arg & DRV_STRENGTH_SEL_MASK)
810 					<< DRV_STRENGTH_SEL_OFF;
811 			break;
812 
813 		default:
814 			dev_err(&gpio_dev->pdev->dev,
815 				"Invalid config param %04x\n", param);
816 			ret = -ENOTSUPP;
817 		}
818 
819 		writel(pin_reg, gpio_dev->base + pin*4);
820 	}
821 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
822 
823 	return ret;
824 }
825 
826 static int amd_pinconf_group_get(struct pinctrl_dev *pctldev,
827 				unsigned int group,
828 				unsigned long *config)
829 {
830 	const unsigned *pins;
831 	unsigned npins;
832 	int ret;
833 
834 	ret = amd_get_group_pins(pctldev, group, &pins, &npins);
835 	if (ret)
836 		return ret;
837 
838 	if (amd_pinconf_get(pctldev, pins[0], config))
839 			return -ENOTSUPP;
840 
841 	return 0;
842 }
843 
844 static int amd_pinconf_group_set(struct pinctrl_dev *pctldev,
845 				unsigned group, unsigned long *configs,
846 				unsigned num_configs)
847 {
848 	const unsigned *pins;
849 	unsigned npins;
850 	int i, ret;
851 
852 	ret = amd_get_group_pins(pctldev, group, &pins, &npins);
853 	if (ret)
854 		return ret;
855 	for (i = 0; i < npins; i++) {
856 		if (amd_pinconf_set(pctldev, pins[i], configs, num_configs))
857 			return -ENOTSUPP;
858 	}
859 	return 0;
860 }
861 
862 static const struct pinconf_ops amd_pinconf_ops = {
863 	.pin_config_get		= amd_pinconf_get,
864 	.pin_config_set		= amd_pinconf_set,
865 	.pin_config_group_get = amd_pinconf_group_get,
866 	.pin_config_group_set = amd_pinconf_group_set,
867 };
868 
869 static void amd_gpio_irq_init(struct amd_gpio *gpio_dev)
870 {
871 	struct pinctrl_desc *desc = gpio_dev->pctrl->desc;
872 	unsigned long flags;
873 	u32 pin_reg, mask;
874 	int i;
875 
876 	mask = BIT(WAKE_CNTRL_OFF_S0I3) | BIT(WAKE_CNTRL_OFF_S3) |
877 		BIT(INTERRUPT_MASK_OFF) | BIT(INTERRUPT_ENABLE_OFF) |
878 		BIT(WAKE_CNTRL_OFF_S4);
879 
880 	for (i = 0; i < desc->npins; i++) {
881 		int pin = desc->pins[i].number;
882 		const struct pin_desc *pd = pin_desc_get(gpio_dev->pctrl, pin);
883 
884 		if (!pd)
885 			continue;
886 
887 		raw_spin_lock_irqsave(&gpio_dev->lock, flags);
888 
889 		pin_reg = readl(gpio_dev->base + i * 4);
890 		pin_reg &= ~mask;
891 		writel(pin_reg, gpio_dev->base + i * 4);
892 
893 		raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
894 	}
895 }
896 
897 #ifdef CONFIG_PM_SLEEP
898 static bool amd_gpio_should_save(struct amd_gpio *gpio_dev, unsigned int pin)
899 {
900 	const struct pin_desc *pd = pin_desc_get(gpio_dev->pctrl, pin);
901 
902 	if (!pd)
903 		return false;
904 
905 	/*
906 	 * Only restore the pin if it is actually in use by the kernel (or
907 	 * by userspace).
908 	 */
909 	if (pd->mux_owner || pd->gpio_owner ||
910 	    gpiochip_line_is_irq(&gpio_dev->gc, pin))
911 		return true;
912 
913 	return false;
914 }
915 
916 static int amd_gpio_suspend(struct device *dev)
917 {
918 	struct amd_gpio *gpio_dev = dev_get_drvdata(dev);
919 	struct pinctrl_desc *desc = gpio_dev->pctrl->desc;
920 	int i;
921 
922 	for (i = 0; i < desc->npins; i++) {
923 		int pin = desc->pins[i].number;
924 
925 		if (!amd_gpio_should_save(gpio_dev, pin))
926 			continue;
927 
928 		gpio_dev->saved_regs[i] = readl(gpio_dev->base + pin*4);
929 	}
930 
931 	return 0;
932 }
933 
934 static int amd_gpio_resume(struct device *dev)
935 {
936 	struct amd_gpio *gpio_dev = dev_get_drvdata(dev);
937 	struct pinctrl_desc *desc = gpio_dev->pctrl->desc;
938 	int i;
939 
940 	for (i = 0; i < desc->npins; i++) {
941 		int pin = desc->pins[i].number;
942 
943 		if (!amd_gpio_should_save(gpio_dev, pin))
944 			continue;
945 
946 		writel(gpio_dev->saved_regs[i], gpio_dev->base + pin*4);
947 	}
948 
949 	return 0;
950 }
951 
952 static const struct dev_pm_ops amd_gpio_pm_ops = {
953 	SET_LATE_SYSTEM_SLEEP_PM_OPS(amd_gpio_suspend,
954 				     amd_gpio_resume)
955 };
956 #endif
957 
958 static struct pinctrl_desc amd_pinctrl_desc = {
959 	.pins	= kerncz_pins,
960 	.npins = ARRAY_SIZE(kerncz_pins),
961 	.pctlops = &amd_pinctrl_ops,
962 	.confops = &amd_pinconf_ops,
963 	.owner = THIS_MODULE,
964 };
965 
966 static int amd_gpio_probe(struct platform_device *pdev)
967 {
968 	int ret = 0;
969 	struct resource *res;
970 	struct amd_gpio *gpio_dev;
971 	struct gpio_irq_chip *girq;
972 
973 	gpio_dev = devm_kzalloc(&pdev->dev,
974 				sizeof(struct amd_gpio), GFP_KERNEL);
975 	if (!gpio_dev)
976 		return -ENOMEM;
977 
978 	raw_spin_lock_init(&gpio_dev->lock);
979 
980 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
981 	if (!res) {
982 		dev_err(&pdev->dev, "Failed to get gpio io resource.\n");
983 		return -EINVAL;
984 	}
985 
986 	gpio_dev->base = devm_ioremap(&pdev->dev, res->start,
987 						resource_size(res));
988 	if (!gpio_dev->base)
989 		return -ENOMEM;
990 
991 	gpio_dev->irq = platform_get_irq(pdev, 0);
992 	if (gpio_dev->irq < 0)
993 		return gpio_dev->irq;
994 
995 #ifdef CONFIG_PM_SLEEP
996 	gpio_dev->saved_regs = devm_kcalloc(&pdev->dev, amd_pinctrl_desc.npins,
997 					    sizeof(*gpio_dev->saved_regs),
998 					    GFP_KERNEL);
999 	if (!gpio_dev->saved_regs)
1000 		return -ENOMEM;
1001 #endif
1002 
1003 	gpio_dev->pdev = pdev;
1004 	gpio_dev->gc.get_direction	= amd_gpio_get_direction;
1005 	gpio_dev->gc.direction_input	= amd_gpio_direction_input;
1006 	gpio_dev->gc.direction_output	= amd_gpio_direction_output;
1007 	gpio_dev->gc.get			= amd_gpio_get_value;
1008 	gpio_dev->gc.set			= amd_gpio_set_value;
1009 	gpio_dev->gc.set_config		= amd_gpio_set_config;
1010 	gpio_dev->gc.dbg_show		= amd_gpio_dbg_show;
1011 
1012 	gpio_dev->gc.base		= -1;
1013 	gpio_dev->gc.label			= pdev->name;
1014 	gpio_dev->gc.owner			= THIS_MODULE;
1015 	gpio_dev->gc.parent			= &pdev->dev;
1016 	gpio_dev->gc.ngpio			= resource_size(res) / 4;
1017 
1018 	gpio_dev->hwbank_num = gpio_dev->gc.ngpio / 64;
1019 	gpio_dev->groups = kerncz_groups;
1020 	gpio_dev->ngroups = ARRAY_SIZE(kerncz_groups);
1021 
1022 	amd_pinctrl_desc.name = dev_name(&pdev->dev);
1023 	gpio_dev->pctrl = devm_pinctrl_register(&pdev->dev, &amd_pinctrl_desc,
1024 						gpio_dev);
1025 	if (IS_ERR(gpio_dev->pctrl)) {
1026 		dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
1027 		return PTR_ERR(gpio_dev->pctrl);
1028 	}
1029 
1030 	/* Disable and mask interrupts */
1031 	amd_gpio_irq_init(gpio_dev);
1032 
1033 	girq = &gpio_dev->gc.irq;
1034 	gpio_irq_chip_set_chip(girq, &amd_gpio_irqchip);
1035 	/* This will let us handle the parent IRQ in the driver */
1036 	girq->parent_handler = NULL;
1037 	girq->num_parents = 0;
1038 	girq->parents = NULL;
1039 	girq->default_type = IRQ_TYPE_NONE;
1040 	girq->handler = handle_simple_irq;
1041 
1042 	ret = gpiochip_add_data(&gpio_dev->gc, gpio_dev);
1043 	if (ret)
1044 		return ret;
1045 
1046 	ret = gpiochip_add_pin_range(&gpio_dev->gc, dev_name(&pdev->dev),
1047 				0, 0, gpio_dev->gc.ngpio);
1048 	if (ret) {
1049 		dev_err(&pdev->dev, "Failed to add pin range\n");
1050 		goto out2;
1051 	}
1052 
1053 	ret = devm_request_irq(&pdev->dev, gpio_dev->irq, amd_gpio_irq_handler,
1054 			       IRQF_SHARED, KBUILD_MODNAME, gpio_dev);
1055 	if (ret)
1056 		goto out2;
1057 
1058 	platform_set_drvdata(pdev, gpio_dev);
1059 	acpi_register_wakeup_handler(gpio_dev->irq, amd_gpio_check_wake, gpio_dev);
1060 
1061 	dev_dbg(&pdev->dev, "amd gpio driver loaded\n");
1062 	return ret;
1063 
1064 out2:
1065 	gpiochip_remove(&gpio_dev->gc);
1066 
1067 	return ret;
1068 }
1069 
1070 static int amd_gpio_remove(struct platform_device *pdev)
1071 {
1072 	struct amd_gpio *gpio_dev;
1073 
1074 	gpio_dev = platform_get_drvdata(pdev);
1075 
1076 	gpiochip_remove(&gpio_dev->gc);
1077 	acpi_unregister_wakeup_handler(amd_gpio_check_wake, gpio_dev);
1078 
1079 	return 0;
1080 }
1081 
1082 #ifdef CONFIG_ACPI
1083 static const struct acpi_device_id amd_gpio_acpi_match[] = {
1084 	{ "AMD0030", 0 },
1085 	{ "AMDI0030", 0},
1086 	{ "AMDI0031", 0},
1087 	{ },
1088 };
1089 MODULE_DEVICE_TABLE(acpi, amd_gpio_acpi_match);
1090 #endif
1091 
1092 static struct platform_driver amd_gpio_driver = {
1093 	.driver		= {
1094 		.name	= "amd_gpio",
1095 		.acpi_match_table = ACPI_PTR(amd_gpio_acpi_match),
1096 #ifdef CONFIG_PM_SLEEP
1097 		.pm	= &amd_gpio_pm_ops,
1098 #endif
1099 	},
1100 	.probe		= amd_gpio_probe,
1101 	.remove		= amd_gpio_remove,
1102 };
1103 
1104 module_platform_driver(amd_gpio_driver);
1105 
1106 MODULE_LICENSE("GPL v2");
1107 MODULE_AUTHOR("Ken Xue <Ken.Xue@amd.com>, Jeff Wu <Jeff.Wu@amd.com>");
1108 MODULE_DESCRIPTION("AMD GPIO pinctrl driver");
1109