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  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Renesas R-Car GPIO Support
  4 *
  5 *  Copyright (C) 2014 Renesas Electronics Corporation
  6 *  Copyright (C) 2013 Magnus Damm
  7 */
  8
  9#include <linux/err.h>
 10#include <linux/gpio/driver.h>
 11#include <linux/init.h>
 12#include <linux/interrupt.h>
 13#include <linux/io.h>
 14#include <linux/ioport.h>
 15#include <linux/irq.h>
 16#include <linux/module.h>
 17#include <linux/of.h>
 18#include <linux/of_device.h>
 19#include <linux/pinctrl/consumer.h>
 20#include <linux/platform_device.h>
 21#include <linux/pm_runtime.h>
 22#include <linux/spinlock.h>
 23#include <linux/slab.h>
 24
 25struct gpio_rcar_bank_info {
 26	u32 iointsel;
 27	u32 inoutsel;
 28	u32 outdt;
 29	u32 posneg;
 30	u32 edglevel;
 31	u32 bothedge;
 32	u32 intmsk;
 33};
 34
 35struct gpio_rcar_priv {
 36	void __iomem *base;
 37	spinlock_t lock;
 38	struct device *dev;
 39	struct gpio_chip gpio_chip;
 40	struct irq_chip irq_chip;
 41	unsigned int irq_parent;
 42	atomic_t wakeup_path;
 43	bool has_outdtsel;
 44	bool has_both_edge_trigger;
 45	struct gpio_rcar_bank_info bank_info;
 46};
 47
 48#define IOINTSEL 0x00	/* General IO/Interrupt Switching Register */
 49#define INOUTSEL 0x04	/* General Input/Output Switching Register */
 50#define OUTDT 0x08	/* General Output Register */
 51#define INDT 0x0c	/* General Input Register */
 52#define INTDT 0x10	/* Interrupt Display Register */
 53#define INTCLR 0x14	/* Interrupt Clear Register */
 54#define INTMSK 0x18	/* Interrupt Mask Register */
 55#define MSKCLR 0x1c	/* Interrupt Mask Clear Register */
 56#define POSNEG 0x20	/* Positive/Negative Logic Select Register */
 57#define EDGLEVEL 0x24	/* Edge/level Select Register */
 58#define FILONOFF 0x28	/* Chattering Prevention On/Off Register */
 59#define OUTDTSEL 0x40	/* Output Data Select Register */
 60#define BOTHEDGE 0x4c	/* One Edge/Both Edge Select Register */
 61
 62#define RCAR_MAX_GPIO_PER_BANK		32
 63
 64static inline u32 gpio_rcar_read(struct gpio_rcar_priv *p, int offs)
 65{
 66	return ioread32(p->base + offs);
 67}
 68
 69static inline void gpio_rcar_write(struct gpio_rcar_priv *p, int offs,
 70				   u32 value)
 71{
 72	iowrite32(value, p->base + offs);
 73}
 74
 75static void gpio_rcar_modify_bit(struct gpio_rcar_priv *p, int offs,
 76				 int bit, bool value)
 77{
 78	u32 tmp = gpio_rcar_read(p, offs);
 79
 80	if (value)
 81		tmp |= BIT(bit);
 82	else
 83		tmp &= ~BIT(bit);
 84
 85	gpio_rcar_write(p, offs, tmp);
 86}
 87
 88static void gpio_rcar_irq_disable(struct irq_data *d)
 89{
 90	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 91	struct gpio_rcar_priv *p = gpiochip_get_data(gc);
 92
 93	gpio_rcar_write(p, INTMSK, ~BIT(irqd_to_hwirq(d)));
 94}
 95
 96static void gpio_rcar_irq_enable(struct irq_data *d)
 97{
 98	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 99	struct gpio_rcar_priv *p = gpiochip_get_data(gc);
100
101	gpio_rcar_write(p, MSKCLR, BIT(irqd_to_hwirq(d)));
102}
103
104static void gpio_rcar_config_interrupt_input_mode(struct gpio_rcar_priv *p,
105						  unsigned int hwirq,
106						  bool active_high_rising_edge,
107						  bool level_trigger,
108						  bool both)
109{
110	unsigned long flags;
111
112	/* follow steps in the GPIO documentation for
113	 * "Setting Edge-Sensitive Interrupt Input Mode" and
114	 * "Setting Level-Sensitive Interrupt Input Mode"
115	 */
116
117	spin_lock_irqsave(&p->lock, flags);
118
119	/* Configure positive or negative logic in POSNEG */
120	gpio_rcar_modify_bit(p, POSNEG, hwirq, !active_high_rising_edge);
121
122	/* Configure edge or level trigger in EDGLEVEL */
123	gpio_rcar_modify_bit(p, EDGLEVEL, hwirq, !level_trigger);
124
125	/* Select one edge or both edges in BOTHEDGE */
126	if (p->has_both_edge_trigger)
127		gpio_rcar_modify_bit(p, BOTHEDGE, hwirq, both);
128
129	/* Select "Interrupt Input Mode" in IOINTSEL */
130	gpio_rcar_modify_bit(p, IOINTSEL, hwirq, true);
131
132	/* Write INTCLR in case of edge trigger */
133	if (!level_trigger)
134		gpio_rcar_write(p, INTCLR, BIT(hwirq));
135
136	spin_unlock_irqrestore(&p->lock, flags);
137}
138
139static int gpio_rcar_irq_set_type(struct irq_data *d, unsigned int type)
140{
141	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
142	struct gpio_rcar_priv *p = gpiochip_get_data(gc);
143	unsigned int hwirq = irqd_to_hwirq(d);
144
145	dev_dbg(p->dev, "sense irq = %d, type = %d\n", hwirq, type);
146
147	switch (type & IRQ_TYPE_SENSE_MASK) {
148	case IRQ_TYPE_LEVEL_HIGH:
149		gpio_rcar_config_interrupt_input_mode(p, hwirq, true, true,
150						      false);
151		break;
152	case IRQ_TYPE_LEVEL_LOW:
153		gpio_rcar_config_interrupt_input_mode(p, hwirq, false, true,
154						      false);
155		break;
156	case IRQ_TYPE_EDGE_RISING:
157		gpio_rcar_config_interrupt_input_mode(p, hwirq, true, false,
158						      false);
159		break;
160	case IRQ_TYPE_EDGE_FALLING:
161		gpio_rcar_config_interrupt_input_mode(p, hwirq, false, false,
162						      false);
163		break;
164	case IRQ_TYPE_EDGE_BOTH:
165		if (!p->has_both_edge_trigger)
166			return -EINVAL;
167		gpio_rcar_config_interrupt_input_mode(p, hwirq, true, false,
168						      true);
169		break;
170	default:
171		return -EINVAL;
172	}
173	return 0;
174}
175
176static int gpio_rcar_irq_set_wake(struct irq_data *d, unsigned int on)
177{
178	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
179	struct gpio_rcar_priv *p = gpiochip_get_data(gc);
180	int error;
181
182	if (p->irq_parent) {
183		error = irq_set_irq_wake(p->irq_parent, on);
184		if (error) {
185			dev_dbg(p->dev, "irq %u doesn't support irq_set_wake\n",
186				p->irq_parent);
187			p->irq_parent = 0;
188		}
189	}
190
191	if (on)
192		atomic_inc(&p->wakeup_path);
193	else
194		atomic_dec(&p->wakeup_path);
195
196	return 0;
197}
198
199static irqreturn_t gpio_rcar_irq_handler(int irq, void *dev_id)
200{
201	struct gpio_rcar_priv *p = dev_id;
202	u32 pending;
203	unsigned int offset, irqs_handled = 0;
204
205	while ((pending = gpio_rcar_read(p, INTDT) &
206			  gpio_rcar_read(p, INTMSK))) {
207		offset = __ffs(pending);
208		gpio_rcar_write(p, INTCLR, BIT(offset));
209		generic_handle_irq(irq_find_mapping(p->gpio_chip.irq.domain,
210						    offset));
211		irqs_handled++;
212	}
213
214	return irqs_handled ? IRQ_HANDLED : IRQ_NONE;
215}
216
217static void gpio_rcar_config_general_input_output_mode(struct gpio_chip *chip,
218						       unsigned int gpio,
219						       bool output)
220{
221	struct gpio_rcar_priv *p = gpiochip_get_data(chip);
222	unsigned long flags;
223
224	/* follow steps in the GPIO documentation for
225	 * "Setting General Output Mode" and
226	 * "Setting General Input Mode"
227	 */
228
229	spin_lock_irqsave(&p->lock, flags);
230
231	/* Configure positive logic in POSNEG */
232	gpio_rcar_modify_bit(p, POSNEG, gpio, false);
233
234	/* Select "General Input/Output Mode" in IOINTSEL */
235	gpio_rcar_modify_bit(p, IOINTSEL, gpio, false);
236
237	/* Select Input Mode or Output Mode in INOUTSEL */
238	gpio_rcar_modify_bit(p, INOUTSEL, gpio, output);
239
240	/* Select General Output Register to output data in OUTDTSEL */
241	if (p->has_outdtsel && output)
242		gpio_rcar_modify_bit(p, OUTDTSEL, gpio, false);
243
244	spin_unlock_irqrestore(&p->lock, flags);
245}
246
247static int gpio_rcar_request(struct gpio_chip *chip, unsigned offset)
248{
249	struct gpio_rcar_priv *p = gpiochip_get_data(chip);
250	int error;
251
252	error = pm_runtime_get_sync(p->dev);
253	if (error < 0) {
254		pm_runtime_put(p->dev);
255		return error;
256	}
257
258	error = pinctrl_gpio_request(chip->base + offset);
259	if (error)
260		pm_runtime_put(p->dev);
261
262	return error;
263}
264
265static void gpio_rcar_free(struct gpio_chip *chip, unsigned offset)
266{
267	struct gpio_rcar_priv *p = gpiochip_get_data(chip);
268
269	pinctrl_gpio_free(chip->base + offset);
270
271	/*
272	 * Set the GPIO as an input to ensure that the next GPIO request won't
273	 * drive the GPIO pin as an output.
274	 */
275	gpio_rcar_config_general_input_output_mode(chip, offset, false);
276
277	pm_runtime_put(p->dev);
278}
279
280static int gpio_rcar_get_direction(struct gpio_chip *chip, unsigned int offset)
281{
282	struct gpio_rcar_priv *p = gpiochip_get_data(chip);
283
284	if (gpio_rcar_read(p, INOUTSEL) & BIT(offset))
285		return GPIO_LINE_DIRECTION_OUT;
286
287	return GPIO_LINE_DIRECTION_IN;
288}
289
290static int gpio_rcar_direction_input(struct gpio_chip *chip, unsigned offset)
291{
292	gpio_rcar_config_general_input_output_mode(chip, offset, false);
293	return 0;
294}
295
296static int gpio_rcar_get(struct gpio_chip *chip, unsigned offset)
297{
298	u32 bit = BIT(offset);
299
300	/* testing on r8a7790 shows that INDT does not show correct pin state
301	 * when configured as output, so use OUTDT in case of output pins */
302	if (gpio_rcar_read(gpiochip_get_data(chip), INOUTSEL) & bit)
303		return !!(gpio_rcar_read(gpiochip_get_data(chip), OUTDT) & bit);
304	else
305		return !!(gpio_rcar_read(gpiochip_get_data(chip), INDT) & bit);
306}
307
308static void gpio_rcar_set(struct gpio_chip *chip, unsigned offset, int value)
309{
310	struct gpio_rcar_priv *p = gpiochip_get_data(chip);
311	unsigned long flags;
312
313	spin_lock_irqsave(&p->lock, flags);
314	gpio_rcar_modify_bit(p, OUTDT, offset, value);
315	spin_unlock_irqrestore(&p->lock, flags);
316}
317
318static void gpio_rcar_set_multiple(struct gpio_chip *chip, unsigned long *mask,
319				   unsigned long *bits)
320{
321	struct gpio_rcar_priv *p = gpiochip_get_data(chip);
322	unsigned long flags;
323	u32 val, bankmask;
324
325	bankmask = mask[0] & GENMASK(chip->ngpio - 1, 0);
326	if (chip->valid_mask)
327		bankmask &= chip->valid_mask[0];
328
329	if (!bankmask)
330		return;
331
332	spin_lock_irqsave(&p->lock, flags);
333	val = gpio_rcar_read(p, OUTDT);
334	val &= ~bankmask;
335	val |= (bankmask & bits[0]);
336	gpio_rcar_write(p, OUTDT, val);
337	spin_unlock_irqrestore(&p->lock, flags);
338}
339
340static int gpio_rcar_direction_output(struct gpio_chip *chip, unsigned offset,
341				      int value)
342{
343	/* write GPIO value to output before selecting output mode of pin */
344	gpio_rcar_set(chip, offset, value);
345	gpio_rcar_config_general_input_output_mode(chip, offset, true);
346	return 0;
347}
348
349struct gpio_rcar_info {
350	bool has_outdtsel;
351	bool has_both_edge_trigger;
352};
353
354static const struct gpio_rcar_info gpio_rcar_info_gen1 = {
355	.has_outdtsel = false,
356	.has_both_edge_trigger = false,
357};
358
359static const struct gpio_rcar_info gpio_rcar_info_gen2 = {
360	.has_outdtsel = true,
361	.has_both_edge_trigger = true,
362};
363
364static const struct of_device_id gpio_rcar_of_table[] = {
365	{
366		.compatible = "renesas,gpio-r8a7743",
367		/* RZ/G1 GPIO is identical to R-Car Gen2. */
368		.data = &gpio_rcar_info_gen2,
369	}, {
370		.compatible = "renesas,gpio-r8a7790",
371		.data = &gpio_rcar_info_gen2,
372	}, {
373		.compatible = "renesas,gpio-r8a7791",
374		.data = &gpio_rcar_info_gen2,
375	}, {
376		.compatible = "renesas,gpio-r8a7792",
377		.data = &gpio_rcar_info_gen2,
378	}, {
379		.compatible = "renesas,gpio-r8a7793",
380		.data = &gpio_rcar_info_gen2,
381	}, {
382		.compatible = "renesas,gpio-r8a7794",
383		.data = &gpio_rcar_info_gen2,
384	}, {
385		.compatible = "renesas,gpio-r8a7795",
386		/* Gen3 GPIO is identical to Gen2. */
387		.data = &gpio_rcar_info_gen2,
388	}, {
389		.compatible = "renesas,gpio-r8a7796",
390		/* Gen3 GPIO is identical to Gen2. */
391		.data = &gpio_rcar_info_gen2,
392	}, {
393		.compatible = "renesas,rcar-gen1-gpio",
394		.data = &gpio_rcar_info_gen1,
395	}, {
396		.compatible = "renesas,rcar-gen2-gpio",
397		.data = &gpio_rcar_info_gen2,
398	}, {
399		.compatible = "renesas,rcar-gen3-gpio",
400		/* Gen3 GPIO is identical to Gen2. */
401		.data = &gpio_rcar_info_gen2,
402	}, {
403		.compatible = "renesas,gpio-rcar",
404		.data = &gpio_rcar_info_gen1,
405	}, {
406		/* Terminator */
407	},
408};
409
410MODULE_DEVICE_TABLE(of, gpio_rcar_of_table);
411
412static int gpio_rcar_parse_dt(struct gpio_rcar_priv *p, unsigned int *npins)
413{
414	struct device_node *np = p->dev->of_node;
415	const struct gpio_rcar_info *info;
416	struct of_phandle_args args;
417	int ret;
418
419	info = of_device_get_match_data(p->dev);
420	p->has_outdtsel = info->has_outdtsel;
421	p->has_both_edge_trigger = info->has_both_edge_trigger;
422
423	ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 0, &args);
424	*npins = ret == 0 ? args.args[2] : RCAR_MAX_GPIO_PER_BANK;
425
426	if (*npins == 0 || *npins > RCAR_MAX_GPIO_PER_BANK) {
427		dev_warn(p->dev, "Invalid number of gpio lines %u, using %u\n",
428			 *npins, RCAR_MAX_GPIO_PER_BANK);
429		*npins = RCAR_MAX_GPIO_PER_BANK;
430	}
431
432	return 0;
433}
434
435static int gpio_rcar_probe(struct platform_device *pdev)
436{
437	struct gpio_rcar_priv *p;
438	struct resource *irq;
439	struct gpio_chip *gpio_chip;
440	struct irq_chip *irq_chip;
441	struct gpio_irq_chip *girq;
442	struct device *dev = &pdev->dev;
443	const char *name = dev_name(dev);
444	unsigned int npins;
445	int ret;
446
447	p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL);
448	if (!p)
449		return -ENOMEM;
450
451	p->dev = dev;
452	spin_lock_init(&p->lock);
453
454	/* Get device configuration from DT node */
455	ret = gpio_rcar_parse_dt(p, &npins);
456	if (ret < 0)
457		return ret;
458
459	platform_set_drvdata(pdev, p);
460
461	pm_runtime_enable(dev);
462
463	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
464	if (!irq) {
465		dev_err(dev, "missing IRQ\n");
466		ret = -EINVAL;
467		goto err0;
468	}
469
470	p->base = devm_platform_ioremap_resource(pdev, 0);
471	if (IS_ERR(p->base)) {
472		ret = PTR_ERR(p->base);
473		goto err0;
474	}
475
476	gpio_chip = &p->gpio_chip;
477	gpio_chip->request = gpio_rcar_request;
478	gpio_chip->free = gpio_rcar_free;
479	gpio_chip->get_direction = gpio_rcar_get_direction;
480	gpio_chip->direction_input = gpio_rcar_direction_input;
481	gpio_chip->get = gpio_rcar_get;
482	gpio_chip->direction_output = gpio_rcar_direction_output;
483	gpio_chip->set = gpio_rcar_set;
484	gpio_chip->set_multiple = gpio_rcar_set_multiple;
485	gpio_chip->label = name;
486	gpio_chip->parent = dev;
487	gpio_chip->owner = THIS_MODULE;
488	gpio_chip->base = -1;
489	gpio_chip->ngpio = npins;
490
491	irq_chip = &p->irq_chip;
492	irq_chip->name = "gpio-rcar";
493	irq_chip->parent_device = dev;
494	irq_chip->irq_mask = gpio_rcar_irq_disable;
495	irq_chip->irq_unmask = gpio_rcar_irq_enable;
496	irq_chip->irq_set_type = gpio_rcar_irq_set_type;
497	irq_chip->irq_set_wake = gpio_rcar_irq_set_wake;
498	irq_chip->flags = IRQCHIP_SET_TYPE_MASKED | IRQCHIP_MASK_ON_SUSPEND;
499
500	girq = &gpio_chip->irq;
501	girq->chip = irq_chip;
502	/* This will let us handle the parent IRQ in the driver */
503	girq->parent_handler = NULL;
504	girq->num_parents = 0;
505	girq->parents = NULL;
506	girq->default_type = IRQ_TYPE_NONE;
507	girq->handler = handle_level_irq;
508
509	ret = gpiochip_add_data(gpio_chip, p);
510	if (ret) {
511		dev_err(dev, "failed to add GPIO controller\n");
512		goto err0;
513	}
514
515	p->irq_parent = irq->start;
516	if (devm_request_irq(dev, irq->start, gpio_rcar_irq_handler,
517			     IRQF_SHARED, name, p)) {
518		dev_err(dev, "failed to request IRQ\n");
519		ret = -ENOENT;
520		goto err1;
521	}
522
523	dev_info(dev, "driving %d GPIOs\n", npins);
524
525	return 0;
526
527err1:
528	gpiochip_remove(gpio_chip);
529err0:
530	pm_runtime_disable(dev);
531	return ret;
532}
533
534static int gpio_rcar_remove(struct platform_device *pdev)
535{
536	struct gpio_rcar_priv *p = platform_get_drvdata(pdev);
537
538	gpiochip_remove(&p->gpio_chip);
539
540	pm_runtime_disable(&pdev->dev);
541	return 0;
542}
543
544#ifdef CONFIG_PM_SLEEP
545static int gpio_rcar_suspend(struct device *dev)
546{
547	struct gpio_rcar_priv *p = dev_get_drvdata(dev);
548
549	p->bank_info.iointsel = gpio_rcar_read(p, IOINTSEL);
550	p->bank_info.inoutsel = gpio_rcar_read(p, INOUTSEL);
551	p->bank_info.outdt = gpio_rcar_read(p, OUTDT);
552	p->bank_info.intmsk = gpio_rcar_read(p, INTMSK);
553	p->bank_info.posneg = gpio_rcar_read(p, POSNEG);
554	p->bank_info.edglevel = gpio_rcar_read(p, EDGLEVEL);
555	if (p->has_both_edge_trigger)
556		p->bank_info.bothedge = gpio_rcar_read(p, BOTHEDGE);
557
558	if (atomic_read(&p->wakeup_path))
559		device_set_wakeup_path(dev);
560
561	return 0;
562}
563
564static int gpio_rcar_resume(struct device *dev)
565{
566	struct gpio_rcar_priv *p = dev_get_drvdata(dev);
567	unsigned int offset;
568	u32 mask;
569
570	for (offset = 0; offset < p->gpio_chip.ngpio; offset++) {
571		if (!gpiochip_line_is_valid(&p->gpio_chip, offset))
572			continue;
573
574		mask = BIT(offset);
575		/* I/O pin */
576		if (!(p->bank_info.iointsel & mask)) {
577			if (p->bank_info.inoutsel & mask)
578				gpio_rcar_direction_output(
579					&p->gpio_chip, offset,
580					!!(p->bank_info.outdt & mask));
581			else
582				gpio_rcar_direction_input(&p->gpio_chip,
583							  offset);
584		} else {
585			/* Interrupt pin */
586			gpio_rcar_config_interrupt_input_mode(
587				p,
588				offset,
589				!(p->bank_info.posneg & mask),
590				!(p->bank_info.edglevel & mask),
591				!!(p->bank_info.bothedge & mask));
592
593			if (p->bank_info.intmsk & mask)
594				gpio_rcar_write(p, MSKCLR, mask);
595		}
596	}
597
598	return 0;
599}
600#endif /* CONFIG_PM_SLEEP*/
601
602static SIMPLE_DEV_PM_OPS(gpio_rcar_pm_ops, gpio_rcar_suspend, gpio_rcar_resume);
603
604static struct platform_driver gpio_rcar_device_driver = {
605	.probe		= gpio_rcar_probe,
606	.remove		= gpio_rcar_remove,
607	.driver		= {
608		.name	= "gpio_rcar",
609		.pm     = &gpio_rcar_pm_ops,
610		.of_match_table = of_match_ptr(gpio_rcar_of_table),
611	}
612};
613
614module_platform_driver(gpio_rcar_device_driver);
615
616MODULE_AUTHOR("Magnus Damm");
617MODULE_DESCRIPTION("Renesas R-Car GPIO Driver");
618MODULE_LICENSE("GPL v2");