xref: /linux/drivers/gpio/gpio-xgs-iproc.c (revision 23c48a124b469cee2eb0c75e6d22d366d1caa118)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2017 Broadcom
4  */
5 
6 #include <linux/gpio/driver.h>
7 #include <linux/init.h>
8 #include <linux/interrupt.h>
9 #include <linux/io.h>
10 #include <linux/irq.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/spinlock.h>
15 
16 #define IPROC_CCA_INT_F_GPIOINT		BIT(0)
17 #define IPROC_CCA_INT_STS		0x20
18 #define IPROC_CCA_INT_MASK		0x24
19 
20 #define IPROC_GPIO_CCA_DIN		0x0
21 #define IPROC_GPIO_CCA_DOUT		0x4
22 #define IPROC_GPIO_CCA_OUT_EN		0x8
23 #define IPROC_GPIO_CCA_INT_LEVEL	0x10
24 #define IPROC_GPIO_CCA_INT_LEVEL_MASK	0x14
25 #define IPROC_GPIO_CCA_INT_EVENT	0x18
26 #define IPROC_GPIO_CCA_INT_EVENT_MASK	0x1C
27 #define IPROC_GPIO_CCA_INT_EDGE		0x24
28 
29 struct iproc_gpio_chip {
30 	struct irq_chip irqchip;
31 	struct gpio_chip gc;
32 	spinlock_t lock;
33 	struct device *dev;
34 	void __iomem *base;
35 	void __iomem *intr;
36 };
37 
38 static inline struct iproc_gpio_chip *
39 to_iproc_gpio(struct gpio_chip *gc)
40 {
41 	return container_of(gc, struct iproc_gpio_chip, gc);
42 }
43 
44 static void iproc_gpio_irq_ack(struct irq_data *d)
45 {
46 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
47 	struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
48 	int pin = d->hwirq;
49 	unsigned long flags;
50 	u32 irq = d->irq;
51 	u32 irq_type, event_status = 0;
52 
53 	spin_lock_irqsave(&chip->lock, flags);
54 	irq_type = irq_get_trigger_type(irq);
55 	if (irq_type & IRQ_TYPE_EDGE_BOTH) {
56 		event_status |= BIT(pin);
57 		writel_relaxed(event_status,
58 			       chip->base + IPROC_GPIO_CCA_INT_EVENT);
59 	}
60 	spin_unlock_irqrestore(&chip->lock, flags);
61 }
62 
63 static void iproc_gpio_irq_unmask(struct irq_data *d)
64 {
65 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
66 	struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
67 	int pin = d->hwirq;
68 	unsigned long flags;
69 	u32 irq = d->irq;
70 	u32 int_mask, irq_type, event_mask;
71 
72 	spin_lock_irqsave(&chip->lock, flags);
73 	irq_type = irq_get_trigger_type(irq);
74 	event_mask = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
75 	int_mask = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
76 
77 	if (irq_type & IRQ_TYPE_EDGE_BOTH) {
78 		event_mask |= 1 << pin;
79 		writel_relaxed(event_mask,
80 			       chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
81 	} else {
82 		int_mask |= 1 << pin;
83 		writel_relaxed(int_mask,
84 			       chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
85 	}
86 	spin_unlock_irqrestore(&chip->lock, flags);
87 }
88 
89 static void iproc_gpio_irq_mask(struct irq_data *d)
90 {
91 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
92 	struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
93 	int pin = d->hwirq;
94 	unsigned long flags;
95 	u32 irq = d->irq;
96 	u32 irq_type, int_mask, event_mask;
97 
98 	spin_lock_irqsave(&chip->lock, flags);
99 	irq_type = irq_get_trigger_type(irq);
100 	event_mask = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
101 	int_mask = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
102 
103 	if (irq_type & IRQ_TYPE_EDGE_BOTH) {
104 		event_mask &= ~BIT(pin);
105 		writel_relaxed(event_mask,
106 			       chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
107 	} else {
108 		int_mask &= ~BIT(pin);
109 		writel_relaxed(int_mask,
110 			       chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
111 	}
112 	spin_unlock_irqrestore(&chip->lock, flags);
113 }
114 
115 static int iproc_gpio_irq_set_type(struct irq_data *d, u32 type)
116 {
117 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
118 	struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
119 	int pin = d->hwirq;
120 	unsigned long flags;
121 	u32 irq = d->irq;
122 	u32 event_pol, int_pol;
123 	int ret = 0;
124 
125 	spin_lock_irqsave(&chip->lock, flags);
126 	switch (type & IRQ_TYPE_SENSE_MASK) {
127 	case IRQ_TYPE_EDGE_RISING:
128 		event_pol = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EDGE);
129 		event_pol &= ~BIT(pin);
130 		writel_relaxed(event_pol, chip->base + IPROC_GPIO_CCA_INT_EDGE);
131 		break;
132 	case IRQ_TYPE_EDGE_FALLING:
133 		event_pol = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EDGE);
134 		event_pol |= BIT(pin);
135 		writel_relaxed(event_pol, chip->base + IPROC_GPIO_CCA_INT_EDGE);
136 		break;
137 	case IRQ_TYPE_LEVEL_HIGH:
138 		int_pol = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL);
139 		int_pol &= ~BIT(pin);
140 		writel_relaxed(int_pol, chip->base + IPROC_GPIO_CCA_INT_LEVEL);
141 		break;
142 	case IRQ_TYPE_LEVEL_LOW:
143 		int_pol = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL);
144 		int_pol |= BIT(pin);
145 		writel_relaxed(int_pol, chip->base + IPROC_GPIO_CCA_INT_LEVEL);
146 		break;
147 	default:
148 		/* should not come here */
149 		ret = -EINVAL;
150 		goto out_unlock;
151 	}
152 
153 	if (type & IRQ_TYPE_LEVEL_MASK)
154 		irq_set_handler_locked(irq_get_irq_data(irq), handle_level_irq);
155 	else if (type & IRQ_TYPE_EDGE_BOTH)
156 		irq_set_handler_locked(irq_get_irq_data(irq), handle_edge_irq);
157 
158 out_unlock:
159 	spin_unlock_irqrestore(&chip->lock, flags);
160 
161 	return ret;
162 }
163 
164 static irqreturn_t iproc_gpio_irq_handler(int irq, void *data)
165 {
166 	struct gpio_chip *gc = (struct gpio_chip *)data;
167 	struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
168 	int bit;
169 	unsigned long int_bits = 0;
170 	u32 int_status;
171 
172 	/* go through the entire GPIOs and handle all interrupts */
173 	int_status = readl_relaxed(chip->intr + IPROC_CCA_INT_STS);
174 	if (int_status & IPROC_CCA_INT_F_GPIOINT) {
175 		u32 event, level;
176 
177 		/* Get level and edge interrupts */
178 		event =
179 		    readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
180 		event &= readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EVENT);
181 		level = readl_relaxed(chip->base + IPROC_GPIO_CCA_DIN);
182 		level ^= readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL);
183 		level &=
184 		    readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
185 		int_bits = level | event;
186 
187 		for_each_set_bit(bit, &int_bits, gc->ngpio)
188 			generic_handle_domain_irq(gc->irq.domain, bit);
189 	}
190 
191 	return int_bits ? IRQ_HANDLED : IRQ_NONE;
192 }
193 
194 static int iproc_gpio_probe(struct platform_device *pdev)
195 {
196 	struct device *dev = &pdev->dev;
197 	struct device_node *dn = pdev->dev.of_node;
198 	struct iproc_gpio_chip *chip;
199 	u32 num_gpios;
200 	int irq, ret;
201 
202 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
203 	if (!chip)
204 		return -ENOMEM;
205 
206 	chip->dev = dev;
207 	platform_set_drvdata(pdev, chip);
208 	spin_lock_init(&chip->lock);
209 
210 	chip->base = devm_platform_ioremap_resource(pdev, 0);
211 	if (IS_ERR(chip->base))
212 		return PTR_ERR(chip->base);
213 
214 	ret = bgpio_init(&chip->gc, dev, 4,
215 			 chip->base + IPROC_GPIO_CCA_DIN,
216 			 chip->base + IPROC_GPIO_CCA_DOUT,
217 			 NULL,
218 			 chip->base + IPROC_GPIO_CCA_OUT_EN,
219 			 NULL,
220 			 0);
221 	if (ret) {
222 		dev_err(dev, "unable to init GPIO chip\n");
223 		return ret;
224 	}
225 
226 	chip->gc.label = dev_name(dev);
227 	if (!of_property_read_u32(dn, "ngpios", &num_gpios))
228 		chip->gc.ngpio = num_gpios;
229 
230 	irq = platform_get_irq(pdev, 0);
231 	if (irq > 0) {
232 		struct gpio_irq_chip *girq;
233 		struct irq_chip *irqc;
234 		u32 val;
235 
236 		irqc = &chip->irqchip;
237 		irqc->name = dev_name(dev);
238 		irqc->irq_ack = iproc_gpio_irq_ack;
239 		irqc->irq_mask = iproc_gpio_irq_mask;
240 		irqc->irq_unmask = iproc_gpio_irq_unmask;
241 		irqc->irq_set_type = iproc_gpio_irq_set_type;
242 
243 		chip->intr = devm_platform_ioremap_resource(pdev, 1);
244 		if (IS_ERR(chip->intr))
245 			return PTR_ERR(chip->intr);
246 
247 		/* Enable GPIO interrupts for CCA GPIO */
248 		val = readl_relaxed(chip->intr + IPROC_CCA_INT_MASK);
249 		val |= IPROC_CCA_INT_F_GPIOINT;
250 		writel_relaxed(val, chip->intr + IPROC_CCA_INT_MASK);
251 
252 		/*
253 		 * Directly request the irq here instead of passing
254 		 * a flow-handler because the irq is shared.
255 		 */
256 		ret = devm_request_irq(dev, irq, iproc_gpio_irq_handler,
257 				       IRQF_SHARED, chip->gc.label, &chip->gc);
258 		if (ret) {
259 			dev_err(dev, "Fail to request IRQ%d: %d\n", irq, ret);
260 			return ret;
261 		}
262 
263 		girq = &chip->gc.irq;
264 		girq->chip = irqc;
265 		/* This will let us handle the parent IRQ in the driver */
266 		girq->parent_handler = NULL;
267 		girq->num_parents = 0;
268 		girq->parents = NULL;
269 		girq->default_type = IRQ_TYPE_NONE;
270 		girq->handler = handle_simple_irq;
271 	}
272 
273 	ret = devm_gpiochip_add_data(dev, &chip->gc, chip);
274 	if (ret) {
275 		dev_err(dev, "unable to add GPIO chip\n");
276 		return ret;
277 	}
278 
279 	return 0;
280 }
281 
282 static int iproc_gpio_remove(struct platform_device *pdev)
283 {
284 	struct iproc_gpio_chip *chip = platform_get_drvdata(pdev);
285 
286 	if (chip->intr) {
287 		u32 val;
288 
289 		val = readl_relaxed(chip->intr + IPROC_CCA_INT_MASK);
290 		val &= ~IPROC_CCA_INT_F_GPIOINT;
291 		writel_relaxed(val, chip->intr + IPROC_CCA_INT_MASK);
292 	}
293 
294 	return 0;
295 }
296 
297 static const struct of_device_id bcm_iproc_gpio_of_match[] = {
298 	{ .compatible = "brcm,iproc-gpio-cca" },
299 	{}
300 };
301 MODULE_DEVICE_TABLE(of, bcm_iproc_gpio_of_match);
302 
303 static struct platform_driver bcm_iproc_gpio_driver = {
304 	.driver = {
305 		.name = "iproc-xgs-gpio",
306 		.of_match_table = bcm_iproc_gpio_of_match,
307 	},
308 	.probe = iproc_gpio_probe,
309 	.remove = iproc_gpio_remove,
310 };
311 
312 module_platform_driver(bcm_iproc_gpio_driver);
313 
314 MODULE_DESCRIPTION("XGS IPROC GPIO driver");
315 MODULE_LICENSE("GPL v2");
316