xref: /openbmc/linux/drivers/pinctrl/pinctrl-amd.c (revision ecd25094)
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 	return !(pin_reg & BIT(OUTPUT_ENABLE_OFF));
50 }
51 
52 static int amd_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
53 {
54 	unsigned long flags;
55 	u32 pin_reg;
56 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
57 
58 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
59 	pin_reg = readl(gpio_dev->base + offset * 4);
60 	pin_reg &= ~BIT(OUTPUT_ENABLE_OFF);
61 	writel(pin_reg, gpio_dev->base + offset * 4);
62 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
63 
64 	return 0;
65 }
66 
67 static int amd_gpio_direction_output(struct gpio_chip *gc, unsigned offset,
68 		int value)
69 {
70 	u32 pin_reg;
71 	unsigned long flags;
72 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
73 
74 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
75 	pin_reg = readl(gpio_dev->base + offset * 4);
76 	pin_reg |= BIT(OUTPUT_ENABLE_OFF);
77 	if (value)
78 		pin_reg |= BIT(OUTPUT_VALUE_OFF);
79 	else
80 		pin_reg &= ~BIT(OUTPUT_VALUE_OFF);
81 	writel(pin_reg, gpio_dev->base + offset * 4);
82 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
83 
84 	return 0;
85 }
86 
87 static int amd_gpio_get_value(struct gpio_chip *gc, unsigned offset)
88 {
89 	u32 pin_reg;
90 	unsigned long flags;
91 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
92 
93 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
94 	pin_reg = readl(gpio_dev->base + offset * 4);
95 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
96 
97 	return !!(pin_reg & BIT(PIN_STS_OFF));
98 }
99 
100 static void amd_gpio_set_value(struct gpio_chip *gc, unsigned offset, int value)
101 {
102 	u32 pin_reg;
103 	unsigned long flags;
104 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
105 
106 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
107 	pin_reg = readl(gpio_dev->base + offset * 4);
108 	if (value)
109 		pin_reg |= BIT(OUTPUT_VALUE_OFF);
110 	else
111 		pin_reg &= ~BIT(OUTPUT_VALUE_OFF);
112 	writel(pin_reg, gpio_dev->base + offset * 4);
113 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
114 }
115 
116 static int amd_gpio_set_debounce(struct gpio_chip *gc, unsigned offset,
117 		unsigned debounce)
118 {
119 	u32 time;
120 	u32 pin_reg;
121 	int ret = 0;
122 	unsigned long flags;
123 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
124 
125 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
126 	pin_reg = readl(gpio_dev->base + offset * 4);
127 
128 	if (debounce) {
129 		pin_reg |= DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF;
130 		pin_reg &= ~DB_TMR_OUT_MASK;
131 		/*
132 		Debounce	Debounce	Timer	Max
133 		TmrLarge	TmrOutUnit	Unit	Debounce
134 							Time
135 		0	0	61 usec (2 RtcClk)	976 usec
136 		0	1	244 usec (8 RtcClk)	3.9 msec
137 		1	0	15.6 msec (512 RtcClk)	250 msec
138 		1	1	62.5 msec (2048 RtcClk)	1 sec
139 		*/
140 
141 		if (debounce < 61) {
142 			pin_reg |= 1;
143 			pin_reg &= ~BIT(DB_TMR_OUT_UNIT_OFF);
144 			pin_reg &= ~BIT(DB_TMR_LARGE_OFF);
145 		} else if (debounce < 976) {
146 			time = debounce / 61;
147 			pin_reg |= time & DB_TMR_OUT_MASK;
148 			pin_reg &= ~BIT(DB_TMR_OUT_UNIT_OFF);
149 			pin_reg &= ~BIT(DB_TMR_LARGE_OFF);
150 		} else if (debounce < 3900) {
151 			time = debounce / 244;
152 			pin_reg |= time & DB_TMR_OUT_MASK;
153 			pin_reg |= BIT(DB_TMR_OUT_UNIT_OFF);
154 			pin_reg &= ~BIT(DB_TMR_LARGE_OFF);
155 		} else if (debounce < 250000) {
156 			time = debounce / 15600;
157 			pin_reg |= time & DB_TMR_OUT_MASK;
158 			pin_reg &= ~BIT(DB_TMR_OUT_UNIT_OFF);
159 			pin_reg |= BIT(DB_TMR_LARGE_OFF);
160 		} else if (debounce < 1000000) {
161 			time = debounce / 62500;
162 			pin_reg |= time & DB_TMR_OUT_MASK;
163 			pin_reg |= BIT(DB_TMR_OUT_UNIT_OFF);
164 			pin_reg |= BIT(DB_TMR_LARGE_OFF);
165 		} else {
166 			pin_reg &= ~DB_CNTRl_MASK;
167 			ret = -EINVAL;
168 		}
169 	} else {
170 		pin_reg &= ~BIT(DB_TMR_OUT_UNIT_OFF);
171 		pin_reg &= ~BIT(DB_TMR_LARGE_OFF);
172 		pin_reg &= ~DB_TMR_OUT_MASK;
173 		pin_reg &= ~DB_CNTRl_MASK;
174 	}
175 	writel(pin_reg, gpio_dev->base + offset * 4);
176 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
177 
178 	return ret;
179 }
180 
181 static int amd_gpio_set_config(struct gpio_chip *gc, unsigned offset,
182 			       unsigned long config)
183 {
184 	u32 debounce;
185 
186 	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
187 		return -ENOTSUPP;
188 
189 	debounce = pinconf_to_config_argument(config);
190 	return amd_gpio_set_debounce(gc, offset, debounce);
191 }
192 
193 #ifdef CONFIG_DEBUG_FS
194 static void amd_gpio_dbg_show(struct seq_file *s, struct gpio_chip *gc)
195 {
196 	u32 pin_reg;
197 	unsigned long flags;
198 	unsigned int bank, i, pin_num;
199 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
200 
201 	char *level_trig;
202 	char *active_level;
203 	char *interrupt_enable;
204 	char *interrupt_mask;
205 	char *wake_cntrl0;
206 	char *wake_cntrl1;
207 	char *wake_cntrl2;
208 	char *pin_sts;
209 	char *pull_up_sel;
210 	char *pull_up_enable;
211 	char *pull_down_enable;
212 	char *output_value;
213 	char *output_enable;
214 
215 	for (bank = 0; bank < gpio_dev->hwbank_num; bank++) {
216 		seq_printf(s, "GPIO bank%d\t", bank);
217 
218 		switch (bank) {
219 		case 0:
220 			i = 0;
221 			pin_num = AMD_GPIO_PINS_BANK0;
222 			break;
223 		case 1:
224 			i = 64;
225 			pin_num = AMD_GPIO_PINS_BANK1 + i;
226 			break;
227 		case 2:
228 			i = 128;
229 			pin_num = AMD_GPIO_PINS_BANK2 + i;
230 			break;
231 		case 3:
232 			i = 192;
233 			pin_num = AMD_GPIO_PINS_BANK3 + i;
234 			break;
235 		default:
236 			/* Illegal bank number, ignore */
237 			continue;
238 		}
239 		for (; i < pin_num; i++) {
240 			seq_printf(s, "pin%d\t", i);
241 			raw_spin_lock_irqsave(&gpio_dev->lock, flags);
242 			pin_reg = readl(gpio_dev->base + i * 4);
243 			raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
244 
245 			if (pin_reg & BIT(INTERRUPT_ENABLE_OFF)) {
246 				u8 level = (pin_reg >> ACTIVE_LEVEL_OFF) &
247 						ACTIVE_LEVEL_MASK;
248 				interrupt_enable = "interrupt is enabled|";
249 
250 				if (level == ACTIVE_LEVEL_HIGH)
251 					active_level = "Active high|";
252 				else if (level == ACTIVE_LEVEL_LOW)
253 					active_level = "Active low|";
254 				else if (!(pin_reg & BIT(LEVEL_TRIG_OFF)) &&
255 					 level == ACTIVE_LEVEL_BOTH)
256 					active_level = "Active on both|";
257 				else
258 					active_level = "Unknown Active level|";
259 
260 				if (pin_reg & BIT(LEVEL_TRIG_OFF))
261 					level_trig = "Level trigger|";
262 				else
263 					level_trig = "Edge trigger|";
264 
265 			} else {
266 				interrupt_enable =
267 					"interrupt is disabled|";
268 				active_level = " ";
269 				level_trig = " ";
270 			}
271 
272 			if (pin_reg & BIT(INTERRUPT_MASK_OFF))
273 				interrupt_mask =
274 					"interrupt is unmasked|";
275 			else
276 				interrupt_mask =
277 					"interrupt is masked|";
278 
279 			if (pin_reg & BIT(WAKE_CNTRL_OFF_S0I3))
280 				wake_cntrl0 = "enable wakeup in S0i3 state|";
281 			else
282 				wake_cntrl0 = "disable wakeup in S0i3 state|";
283 
284 			if (pin_reg & BIT(WAKE_CNTRL_OFF_S3))
285 				wake_cntrl1 = "enable wakeup in S3 state|";
286 			else
287 				wake_cntrl1 = "disable wakeup in S3 state|";
288 
289 			if (pin_reg & BIT(WAKE_CNTRL_OFF_S4))
290 				wake_cntrl2 = "enable wakeup in S4/S5 state|";
291 			else
292 				wake_cntrl2 = "disable wakeup in S4/S5 state|";
293 
294 			if (pin_reg & BIT(PULL_UP_ENABLE_OFF)) {
295 				pull_up_enable = "pull-up is enabled|";
296 				if (pin_reg & BIT(PULL_UP_SEL_OFF))
297 					pull_up_sel = "8k pull-up|";
298 				else
299 					pull_up_sel = "4k pull-up|";
300 			} else {
301 				pull_up_enable = "pull-up is disabled|";
302 				pull_up_sel = " ";
303 			}
304 
305 			if (pin_reg & BIT(PULL_DOWN_ENABLE_OFF))
306 				pull_down_enable = "pull-down is enabled|";
307 			else
308 				pull_down_enable = "Pull-down is disabled|";
309 
310 			if (pin_reg & BIT(OUTPUT_ENABLE_OFF)) {
311 				pin_sts = " ";
312 				output_enable = "output is enabled|";
313 				if (pin_reg & BIT(OUTPUT_VALUE_OFF))
314 					output_value = "output is high|";
315 				else
316 					output_value = "output is low|";
317 			} else {
318 				output_enable = "output is disabled|";
319 				output_value = " ";
320 
321 				if (pin_reg & BIT(PIN_STS_OFF))
322 					pin_sts = "input is high|";
323 				else
324 					pin_sts = "input is low|";
325 			}
326 
327 			seq_printf(s, "%s %s %s %s %s %s\n"
328 				" %s %s %s %s %s %s %s 0x%x\n",
329 				level_trig, active_level, interrupt_enable,
330 				interrupt_mask, wake_cntrl0, wake_cntrl1,
331 				wake_cntrl2, pin_sts, pull_up_sel,
332 				pull_up_enable, pull_down_enable,
333 				output_value, output_enable, pin_reg);
334 		}
335 	}
336 }
337 #else
338 #define amd_gpio_dbg_show NULL
339 #endif
340 
341 static void amd_gpio_irq_enable(struct irq_data *d)
342 {
343 	u32 pin_reg;
344 	unsigned long flags;
345 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
346 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
347 
348 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
349 	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
350 	pin_reg |= BIT(INTERRUPT_ENABLE_OFF);
351 	pin_reg |= BIT(INTERRUPT_MASK_OFF);
352 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
353 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
354 }
355 
356 static void amd_gpio_irq_disable(struct irq_data *d)
357 {
358 	u32 pin_reg;
359 	unsigned long flags;
360 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
361 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
362 
363 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
364 	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
365 	pin_reg &= ~BIT(INTERRUPT_ENABLE_OFF);
366 	pin_reg &= ~BIT(INTERRUPT_MASK_OFF);
367 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
368 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
369 }
370 
371 static void amd_gpio_irq_mask(struct irq_data *d)
372 {
373 	u32 pin_reg;
374 	unsigned long flags;
375 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
376 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
377 
378 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
379 	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
380 	pin_reg &= ~BIT(INTERRUPT_MASK_OFF);
381 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
382 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
383 }
384 
385 static void amd_gpio_irq_unmask(struct irq_data *d)
386 {
387 	u32 pin_reg;
388 	unsigned long flags;
389 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
390 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
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_MASK_OFF);
395 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
396 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
397 }
398 
399 static void amd_gpio_irq_eoi(struct irq_data *d)
400 {
401 	u32 reg;
402 	unsigned long flags;
403 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
404 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
405 
406 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
407 	reg = readl(gpio_dev->base + WAKE_INT_MASTER_REG);
408 	reg |= EOI_MASK;
409 	writel(reg, gpio_dev->base + WAKE_INT_MASTER_REG);
410 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
411 }
412 
413 static int amd_gpio_irq_set_type(struct irq_data *d, unsigned int type)
414 {
415 	int ret = 0;
416 	u32 pin_reg, pin_reg_irq_en, mask;
417 	unsigned long flags, irq_flags;
418 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
419 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
420 
421 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
422 	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
423 
424 	/* Ignore the settings coming from the client and
425 	 * read the values from the ACPI tables
426 	 * while setting the trigger type
427 	 */
428 
429 	irq_flags = irq_get_trigger_type(d->irq);
430 	if (irq_flags != IRQ_TYPE_NONE)
431 		type = irq_flags;
432 
433 	switch (type & IRQ_TYPE_SENSE_MASK) {
434 	case IRQ_TYPE_EDGE_RISING:
435 		pin_reg &= ~BIT(LEVEL_TRIG_OFF);
436 		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
437 		pin_reg |= ACTIVE_HIGH << ACTIVE_LEVEL_OFF;
438 		pin_reg |= DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF;
439 		irq_set_handler_locked(d, handle_edge_irq);
440 		break;
441 
442 	case IRQ_TYPE_EDGE_FALLING:
443 		pin_reg &= ~BIT(LEVEL_TRIG_OFF);
444 		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
445 		pin_reg |= ACTIVE_LOW << ACTIVE_LEVEL_OFF;
446 		pin_reg |= DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF;
447 		irq_set_handler_locked(d, handle_edge_irq);
448 		break;
449 
450 	case IRQ_TYPE_EDGE_BOTH:
451 		pin_reg &= ~BIT(LEVEL_TRIG_OFF);
452 		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
453 		pin_reg |= BOTH_EADGE << ACTIVE_LEVEL_OFF;
454 		pin_reg |= DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF;
455 		irq_set_handler_locked(d, handle_edge_irq);
456 		break;
457 
458 	case IRQ_TYPE_LEVEL_HIGH:
459 		pin_reg |= LEVEL_TRIGGER << LEVEL_TRIG_OFF;
460 		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
461 		pin_reg |= ACTIVE_HIGH << ACTIVE_LEVEL_OFF;
462 		pin_reg &= ~(DB_CNTRl_MASK << DB_CNTRL_OFF);
463 		pin_reg |= DB_TYPE_PRESERVE_LOW_GLITCH << DB_CNTRL_OFF;
464 		irq_set_handler_locked(d, handle_level_irq);
465 		break;
466 
467 	case IRQ_TYPE_LEVEL_LOW:
468 		pin_reg |= LEVEL_TRIGGER << LEVEL_TRIG_OFF;
469 		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
470 		pin_reg |= ACTIVE_LOW << ACTIVE_LEVEL_OFF;
471 		pin_reg &= ~(DB_CNTRl_MASK << DB_CNTRL_OFF);
472 		pin_reg |= DB_TYPE_PRESERVE_HIGH_GLITCH << DB_CNTRL_OFF;
473 		irq_set_handler_locked(d, handle_level_irq);
474 		break;
475 
476 	case IRQ_TYPE_NONE:
477 		break;
478 
479 	default:
480 		dev_err(&gpio_dev->pdev->dev, "Invalid type value\n");
481 		ret = -EINVAL;
482 	}
483 
484 	pin_reg |= CLR_INTR_STAT << INTERRUPT_STS_OFF;
485 	/*
486 	 * If WAKE_INT_MASTER_REG.MaskStsEn is set, a software write to the
487 	 * debounce registers of any GPIO will block wake/interrupt status
488 	 * generation for *all* GPIOs for a length of time that depends on
489 	 * WAKE_INT_MASTER_REG.MaskStsLength[11:0].  During this period the
490 	 * INTERRUPT_ENABLE bit will read as 0.
491 	 *
492 	 * We temporarily enable irq for the GPIO whose configuration is
493 	 * changing, and then wait for it to read back as 1 to know when
494 	 * debounce has settled and then disable the irq again.
495 	 * We do this polling with the spinlock held to ensure other GPIO
496 	 * access routines do not read an incorrect value for the irq enable
497 	 * bit of other GPIOs.  We keep the GPIO masked while polling to avoid
498 	 * spurious irqs, and disable the irq again after polling.
499 	 */
500 	mask = BIT(INTERRUPT_ENABLE_OFF);
501 	pin_reg_irq_en = pin_reg;
502 	pin_reg_irq_en |= mask;
503 	pin_reg_irq_en &= ~BIT(INTERRUPT_MASK_OFF);
504 	writel(pin_reg_irq_en, gpio_dev->base + (d->hwirq)*4);
505 	while ((readl(gpio_dev->base + (d->hwirq)*4) & mask) != mask)
506 		continue;
507 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
508 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
509 
510 	return ret;
511 }
512 
513 static void amd_irq_ack(struct irq_data *d)
514 {
515 	/*
516 	 * based on HW design,there is no need to ack HW
517 	 * before handle current irq. But this routine is
518 	 * necessary for handle_edge_irq
519 	*/
520 }
521 
522 static struct irq_chip amd_gpio_irqchip = {
523 	.name         = "amd_gpio",
524 	.irq_ack      = amd_irq_ack,
525 	.irq_enable   = amd_gpio_irq_enable,
526 	.irq_disable  = amd_gpio_irq_disable,
527 	.irq_mask     = amd_gpio_irq_mask,
528 	.irq_unmask   = amd_gpio_irq_unmask,
529 	.irq_eoi      = amd_gpio_irq_eoi,
530 	.irq_set_type = amd_gpio_irq_set_type,
531 	.flags        = IRQCHIP_SKIP_SET_WAKE,
532 };
533 
534 #define PIN_IRQ_PENDING	(BIT(INTERRUPT_STS_OFF) | BIT(WAKE_STS_OFF))
535 
536 static irqreturn_t amd_gpio_irq_handler(int irq, void *dev_id)
537 {
538 	struct amd_gpio *gpio_dev = dev_id;
539 	struct gpio_chip *gc = &gpio_dev->gc;
540 	irqreturn_t ret = IRQ_NONE;
541 	unsigned int i, irqnr;
542 	unsigned long flags;
543 	u32 *regs, regval;
544 	u64 status, mask;
545 
546 	/* Read the wake status */
547 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
548 	status = readl(gpio_dev->base + WAKE_INT_STATUS_REG1);
549 	status <<= 32;
550 	status |= readl(gpio_dev->base + WAKE_INT_STATUS_REG0);
551 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
552 
553 	/* Bit 0-45 contain the relevant status bits */
554 	status &= (1ULL << 46) - 1;
555 	regs = gpio_dev->base;
556 	for (mask = 1, irqnr = 0; status; mask <<= 1, regs += 4, irqnr += 4) {
557 		if (!(status & mask))
558 			continue;
559 		status &= ~mask;
560 
561 		/* Each status bit covers four pins */
562 		for (i = 0; i < 4; i++) {
563 			regval = readl(regs + i);
564 			if (!(regval & PIN_IRQ_PENDING) ||
565 			    !(regval & BIT(INTERRUPT_MASK_OFF)))
566 				continue;
567 			irq = irq_find_mapping(gc->irq.domain, irqnr + i);
568 			if (irq != 0)
569 				generic_handle_irq(irq);
570 
571 			/* Clear interrupt.
572 			 * We must read the pin register again, in case the
573 			 * value was changed while executing
574 			 * generic_handle_irq() above.
575 			 * If we didn't find a mapping for the interrupt,
576 			 * disable it in order to avoid a system hang caused
577 			 * by an interrupt storm.
578 			 */
579 			raw_spin_lock_irqsave(&gpio_dev->lock, flags);
580 			regval = readl(regs + i);
581 			if (irq == 0) {
582 				regval &= ~BIT(INTERRUPT_ENABLE_OFF);
583 				dev_dbg(&gpio_dev->pdev->dev,
584 					"Disabling spurious GPIO IRQ %d\n",
585 					irqnr + i);
586 			}
587 			writel(regval, regs + i);
588 			raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
589 			ret = IRQ_HANDLED;
590 		}
591 	}
592 
593 	/* Signal EOI to the GPIO unit */
594 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
595 	regval = readl(gpio_dev->base + WAKE_INT_MASTER_REG);
596 	regval |= EOI_MASK;
597 	writel(regval, gpio_dev->base + WAKE_INT_MASTER_REG);
598 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
599 
600 	return ret;
601 }
602 
603 static int amd_get_groups_count(struct pinctrl_dev *pctldev)
604 {
605 	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);
606 
607 	return gpio_dev->ngroups;
608 }
609 
610 static const char *amd_get_group_name(struct pinctrl_dev *pctldev,
611 				      unsigned group)
612 {
613 	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);
614 
615 	return gpio_dev->groups[group].name;
616 }
617 
618 static int amd_get_group_pins(struct pinctrl_dev *pctldev,
619 			      unsigned group,
620 			      const unsigned **pins,
621 			      unsigned *num_pins)
622 {
623 	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);
624 
625 	*pins = gpio_dev->groups[group].pins;
626 	*num_pins = gpio_dev->groups[group].npins;
627 	return 0;
628 }
629 
630 static const struct pinctrl_ops amd_pinctrl_ops = {
631 	.get_groups_count	= amd_get_groups_count,
632 	.get_group_name		= amd_get_group_name,
633 	.get_group_pins		= amd_get_group_pins,
634 #ifdef CONFIG_OF
635 	.dt_node_to_map		= pinconf_generic_dt_node_to_map_group,
636 	.dt_free_map		= pinctrl_utils_free_map,
637 #endif
638 };
639 
640 static int amd_pinconf_get(struct pinctrl_dev *pctldev,
641 			  unsigned int pin,
642 			  unsigned long *config)
643 {
644 	u32 pin_reg;
645 	unsigned arg;
646 	unsigned long flags;
647 	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);
648 	enum pin_config_param param = pinconf_to_config_param(*config);
649 
650 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
651 	pin_reg = readl(gpio_dev->base + pin*4);
652 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
653 	switch (param) {
654 	case PIN_CONFIG_INPUT_DEBOUNCE:
655 		arg = pin_reg & DB_TMR_OUT_MASK;
656 		break;
657 
658 	case PIN_CONFIG_BIAS_PULL_DOWN:
659 		arg = (pin_reg >> PULL_DOWN_ENABLE_OFF) & BIT(0);
660 		break;
661 
662 	case PIN_CONFIG_BIAS_PULL_UP:
663 		arg = (pin_reg >> PULL_UP_SEL_OFF) & (BIT(0) | BIT(1));
664 		break;
665 
666 	case PIN_CONFIG_DRIVE_STRENGTH:
667 		arg = (pin_reg >> DRV_STRENGTH_SEL_OFF) & DRV_STRENGTH_SEL_MASK;
668 		break;
669 
670 	default:
671 		dev_err(&gpio_dev->pdev->dev, "Invalid config param %04x\n",
672 			param);
673 		return -ENOTSUPP;
674 	}
675 
676 	*config = pinconf_to_config_packed(param, arg);
677 
678 	return 0;
679 }
680 
681 static int amd_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
682 				unsigned long *configs, unsigned num_configs)
683 {
684 	int i;
685 	u32 arg;
686 	int ret = 0;
687 	u32 pin_reg;
688 	unsigned long flags;
689 	enum pin_config_param param;
690 	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);
691 
692 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
693 	for (i = 0; i < num_configs; i++) {
694 		param = pinconf_to_config_param(configs[i]);
695 		arg = pinconf_to_config_argument(configs[i]);
696 		pin_reg = readl(gpio_dev->base + pin*4);
697 
698 		switch (param) {
699 		case PIN_CONFIG_INPUT_DEBOUNCE:
700 			pin_reg &= ~DB_TMR_OUT_MASK;
701 			pin_reg |= arg & DB_TMR_OUT_MASK;
702 			break;
703 
704 		case PIN_CONFIG_BIAS_PULL_DOWN:
705 			pin_reg &= ~BIT(PULL_DOWN_ENABLE_OFF);
706 			pin_reg |= (arg & BIT(0)) << PULL_DOWN_ENABLE_OFF;
707 			break;
708 
709 		case PIN_CONFIG_BIAS_PULL_UP:
710 			pin_reg &= ~BIT(PULL_UP_SEL_OFF);
711 			pin_reg |= (arg & BIT(0)) << PULL_UP_SEL_OFF;
712 			pin_reg &= ~BIT(PULL_UP_ENABLE_OFF);
713 			pin_reg |= ((arg>>1) & BIT(0)) << PULL_UP_ENABLE_OFF;
714 			break;
715 
716 		case PIN_CONFIG_DRIVE_STRENGTH:
717 			pin_reg &= ~(DRV_STRENGTH_SEL_MASK
718 					<< DRV_STRENGTH_SEL_OFF);
719 			pin_reg |= (arg & DRV_STRENGTH_SEL_MASK)
720 					<< DRV_STRENGTH_SEL_OFF;
721 			break;
722 
723 		default:
724 			dev_err(&gpio_dev->pdev->dev,
725 				"Invalid config param %04x\n", param);
726 			ret = -ENOTSUPP;
727 		}
728 
729 		writel(pin_reg, gpio_dev->base + pin*4);
730 	}
731 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
732 
733 	return ret;
734 }
735 
736 static int amd_pinconf_group_get(struct pinctrl_dev *pctldev,
737 				unsigned int group,
738 				unsigned long *config)
739 {
740 	const unsigned *pins;
741 	unsigned npins;
742 	int ret;
743 
744 	ret = amd_get_group_pins(pctldev, group, &pins, &npins);
745 	if (ret)
746 		return ret;
747 
748 	if (amd_pinconf_get(pctldev, pins[0], config))
749 			return -ENOTSUPP;
750 
751 	return 0;
752 }
753 
754 static int amd_pinconf_group_set(struct pinctrl_dev *pctldev,
755 				unsigned group, unsigned long *configs,
756 				unsigned num_configs)
757 {
758 	const unsigned *pins;
759 	unsigned npins;
760 	int i, ret;
761 
762 	ret = amd_get_group_pins(pctldev, group, &pins, &npins);
763 	if (ret)
764 		return ret;
765 	for (i = 0; i < npins; i++) {
766 		if (amd_pinconf_set(pctldev, pins[i], configs, num_configs))
767 			return -ENOTSUPP;
768 	}
769 	return 0;
770 }
771 
772 static const struct pinconf_ops amd_pinconf_ops = {
773 	.pin_config_get		= amd_pinconf_get,
774 	.pin_config_set		= amd_pinconf_set,
775 	.pin_config_group_get = amd_pinconf_group_get,
776 	.pin_config_group_set = amd_pinconf_group_set,
777 };
778 
779 #ifdef CONFIG_PM_SLEEP
780 static bool amd_gpio_should_save(struct amd_gpio *gpio_dev, unsigned int pin)
781 {
782 	const struct pin_desc *pd = pin_desc_get(gpio_dev->pctrl, pin);
783 
784 	if (!pd)
785 		return false;
786 
787 	/*
788 	 * Only restore the pin if it is actually in use by the kernel (or
789 	 * by userspace).
790 	 */
791 	if (pd->mux_owner || pd->gpio_owner ||
792 	    gpiochip_line_is_irq(&gpio_dev->gc, pin))
793 		return true;
794 
795 	return false;
796 }
797 
798 static int amd_gpio_suspend(struct device *dev)
799 {
800 	struct amd_gpio *gpio_dev = dev_get_drvdata(dev);
801 	struct pinctrl_desc *desc = gpio_dev->pctrl->desc;
802 	int i;
803 
804 	for (i = 0; i < desc->npins; i++) {
805 		int pin = desc->pins[i].number;
806 
807 		if (!amd_gpio_should_save(gpio_dev, pin))
808 			continue;
809 
810 		gpio_dev->saved_regs[i] = readl(gpio_dev->base + pin*4);
811 	}
812 
813 	return 0;
814 }
815 
816 static int amd_gpio_resume(struct device *dev)
817 {
818 	struct amd_gpio *gpio_dev = dev_get_drvdata(dev);
819 	struct pinctrl_desc *desc = gpio_dev->pctrl->desc;
820 	int i;
821 
822 	for (i = 0; i < desc->npins; i++) {
823 		int pin = desc->pins[i].number;
824 
825 		if (!amd_gpio_should_save(gpio_dev, pin))
826 			continue;
827 
828 		writel(gpio_dev->saved_regs[i], gpio_dev->base + pin*4);
829 	}
830 
831 	return 0;
832 }
833 
834 static const struct dev_pm_ops amd_gpio_pm_ops = {
835 	SET_LATE_SYSTEM_SLEEP_PM_OPS(amd_gpio_suspend,
836 				     amd_gpio_resume)
837 };
838 #endif
839 
840 static struct pinctrl_desc amd_pinctrl_desc = {
841 	.pins	= kerncz_pins,
842 	.npins = ARRAY_SIZE(kerncz_pins),
843 	.pctlops = &amd_pinctrl_ops,
844 	.confops = &amd_pinconf_ops,
845 	.owner = THIS_MODULE,
846 };
847 
848 static int amd_gpio_probe(struct platform_device *pdev)
849 {
850 	int ret = 0;
851 	int irq_base;
852 	struct resource *res;
853 	struct amd_gpio *gpio_dev;
854 
855 	gpio_dev = devm_kzalloc(&pdev->dev,
856 				sizeof(struct amd_gpio), GFP_KERNEL);
857 	if (!gpio_dev)
858 		return -ENOMEM;
859 
860 	raw_spin_lock_init(&gpio_dev->lock);
861 
862 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
863 	if (!res) {
864 		dev_err(&pdev->dev, "Failed to get gpio io resource.\n");
865 		return -EINVAL;
866 	}
867 
868 	gpio_dev->base = devm_ioremap_nocache(&pdev->dev, res->start,
869 						resource_size(res));
870 	if (!gpio_dev->base)
871 		return -ENOMEM;
872 
873 	irq_base = platform_get_irq(pdev, 0);
874 	if (irq_base < 0)
875 		return irq_base;
876 
877 #ifdef CONFIG_PM_SLEEP
878 	gpio_dev->saved_regs = devm_kcalloc(&pdev->dev, amd_pinctrl_desc.npins,
879 					    sizeof(*gpio_dev->saved_regs),
880 					    GFP_KERNEL);
881 	if (!gpio_dev->saved_regs)
882 		return -ENOMEM;
883 #endif
884 
885 	gpio_dev->pdev = pdev;
886 	gpio_dev->gc.get_direction	= amd_gpio_get_direction;
887 	gpio_dev->gc.direction_input	= amd_gpio_direction_input;
888 	gpio_dev->gc.direction_output	= amd_gpio_direction_output;
889 	gpio_dev->gc.get			= amd_gpio_get_value;
890 	gpio_dev->gc.set			= amd_gpio_set_value;
891 	gpio_dev->gc.set_config		= amd_gpio_set_config;
892 	gpio_dev->gc.dbg_show		= amd_gpio_dbg_show;
893 
894 	gpio_dev->gc.base		= -1;
895 	gpio_dev->gc.label			= pdev->name;
896 	gpio_dev->gc.owner			= THIS_MODULE;
897 	gpio_dev->gc.parent			= &pdev->dev;
898 	gpio_dev->gc.ngpio			= resource_size(res) / 4;
899 #if defined(CONFIG_OF_GPIO)
900 	gpio_dev->gc.of_node			= pdev->dev.of_node;
901 #endif
902 
903 	gpio_dev->hwbank_num = gpio_dev->gc.ngpio / 64;
904 	gpio_dev->groups = kerncz_groups;
905 	gpio_dev->ngroups = ARRAY_SIZE(kerncz_groups);
906 
907 	amd_pinctrl_desc.name = dev_name(&pdev->dev);
908 	gpio_dev->pctrl = devm_pinctrl_register(&pdev->dev, &amd_pinctrl_desc,
909 						gpio_dev);
910 	if (IS_ERR(gpio_dev->pctrl)) {
911 		dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
912 		return PTR_ERR(gpio_dev->pctrl);
913 	}
914 
915 	ret = gpiochip_add_data(&gpio_dev->gc, gpio_dev);
916 	if (ret)
917 		return ret;
918 
919 	ret = gpiochip_add_pin_range(&gpio_dev->gc, dev_name(&pdev->dev),
920 				0, 0, gpio_dev->gc.ngpio);
921 	if (ret) {
922 		dev_err(&pdev->dev, "Failed to add pin range\n");
923 		goto out2;
924 	}
925 
926 	ret = gpiochip_irqchip_add(&gpio_dev->gc,
927 				&amd_gpio_irqchip,
928 				0,
929 				handle_simple_irq,
930 				IRQ_TYPE_NONE);
931 	if (ret) {
932 		dev_err(&pdev->dev, "could not add irqchip\n");
933 		ret = -ENODEV;
934 		goto out2;
935 	}
936 
937 	ret = devm_request_irq(&pdev->dev, irq_base, amd_gpio_irq_handler,
938 			       IRQF_SHARED, KBUILD_MODNAME, gpio_dev);
939 	if (ret)
940 		goto out2;
941 
942 	platform_set_drvdata(pdev, gpio_dev);
943 
944 	dev_dbg(&pdev->dev, "amd gpio driver loaded\n");
945 	return ret;
946 
947 out2:
948 	gpiochip_remove(&gpio_dev->gc);
949 
950 	return ret;
951 }
952 
953 static int amd_gpio_remove(struct platform_device *pdev)
954 {
955 	struct amd_gpio *gpio_dev;
956 
957 	gpio_dev = platform_get_drvdata(pdev);
958 
959 	gpiochip_remove(&gpio_dev->gc);
960 
961 	return 0;
962 }
963 
964 static const struct acpi_device_id amd_gpio_acpi_match[] = {
965 	{ "AMD0030", 0 },
966 	{ "AMDI0030", 0},
967 	{ },
968 };
969 MODULE_DEVICE_TABLE(acpi, amd_gpio_acpi_match);
970 
971 static struct platform_driver amd_gpio_driver = {
972 	.driver		= {
973 		.name	= "amd_gpio",
974 		.acpi_match_table = ACPI_PTR(amd_gpio_acpi_match),
975 #ifdef CONFIG_PM_SLEEP
976 		.pm	= &amd_gpio_pm_ops,
977 #endif
978 	},
979 	.probe		= amd_gpio_probe,
980 	.remove		= amd_gpio_remove,
981 };
982 
983 module_platform_driver(amd_gpio_driver);
984 
985 MODULE_LICENSE("GPL v2");
986 MODULE_AUTHOR("Ken Xue <Ken.Xue@amd.com>, Jeff Wu <Jeff.Wu@amd.com>");
987 MODULE_DESCRIPTION("AMD GPIO pinctrl driver");
988