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 *
to_iproc_gpio(struct gpio_chip * gc)39 to_iproc_gpio(struct gpio_chip *gc)
40 {
41 return container_of(gc, struct iproc_gpio_chip, gc);
42 }
43
iproc_gpio_irq_ack(struct irq_data * d)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
iproc_gpio_irq_unmask(struct irq_data * d)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
iproc_gpio_irq_mask(struct irq_data * d)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
iproc_gpio_irq_set_type(struct irq_data * d,u32 type)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
iproc_gpio_irq_handler(int irq,void * data)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_irq(irq_linear_revmap(gc->irq.domain, bit));
189 }
190
191 return int_bits ? IRQ_HANDLED : IRQ_NONE;
192 }
193
iproc_gpio_probe(struct platform_device * pdev)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
iproc_gpio_remove(struct platform_device * pdev)282 static int iproc_gpio_remove(struct platform_device *pdev)
283 {
284 struct iproc_gpio_chip *chip;
285
286 chip = platform_get_drvdata(pdev);
287 if (!chip)
288 return -ENODEV;
289
290 if (chip->intr) {
291 u32 val;
292
293 val = readl_relaxed(chip->intr + IPROC_CCA_INT_MASK);
294 val &= ~IPROC_CCA_INT_F_GPIOINT;
295 writel_relaxed(val, chip->intr + IPROC_CCA_INT_MASK);
296 }
297
298 return 0;
299 }
300
301 static const struct of_device_id bcm_iproc_gpio_of_match[] = {
302 { .compatible = "brcm,iproc-gpio-cca" },
303 {}
304 };
305 MODULE_DEVICE_TABLE(of, bcm_iproc_gpio_of_match);
306
307 static struct platform_driver bcm_iproc_gpio_driver = {
308 .driver = {
309 .name = "iproc-xgs-gpio",
310 .of_match_table = bcm_iproc_gpio_of_match,
311 },
312 .probe = iproc_gpio_probe,
313 .remove = iproc_gpio_remove,
314 };
315
316 module_platform_driver(bcm_iproc_gpio_driver);
317
318 MODULE_DESCRIPTION("XGS IPROC GPIO driver");
319 MODULE_LICENSE("GPL v2");
320
