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/seq_file.h>
15 #include <linux/spinlock.h>
16
17 #define IPROC_CCA_INT_F_GPIOINT BIT(0)
18 #define IPROC_CCA_INT_STS 0x20
19 #define IPROC_CCA_INT_MASK 0x24
20
21 #define IPROC_GPIO_CCA_DIN 0x0
22 #define IPROC_GPIO_CCA_DOUT 0x4
23 #define IPROC_GPIO_CCA_OUT_EN 0x8
24 #define IPROC_GPIO_CCA_INT_LEVEL 0x10
25 #define IPROC_GPIO_CCA_INT_LEVEL_MASK 0x14
26 #define IPROC_GPIO_CCA_INT_EVENT 0x18
27 #define IPROC_GPIO_CCA_INT_EVENT_MASK 0x1C
28 #define IPROC_GPIO_CCA_INT_EDGE 0x24
29
30 struct iproc_gpio_chip {
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 gpiochip_enable_irq(gc, pin);
73 spin_lock_irqsave(&chip->lock, flags);
74 irq_type = irq_get_trigger_type(irq);
75 event_mask = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
76 int_mask = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
77
78 if (irq_type & IRQ_TYPE_EDGE_BOTH) {
79 event_mask |= 1 << pin;
80 writel_relaxed(event_mask,
81 chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
82 } else {
83 int_mask |= 1 << pin;
84 writel_relaxed(int_mask,
85 chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
86 }
87 spin_unlock_irqrestore(&chip->lock, flags);
88 }
89
iproc_gpio_irq_mask(struct irq_data * d)90 static void iproc_gpio_irq_mask(struct irq_data *d)
91 {
92 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
93 struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
94 int pin = d->hwirq;
95 unsigned long flags;
96 u32 irq = d->irq;
97 u32 irq_type, int_mask, event_mask;
98
99 spin_lock_irqsave(&chip->lock, flags);
100 irq_type = irq_get_trigger_type(irq);
101 event_mask = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
102 int_mask = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
103
104 if (irq_type & IRQ_TYPE_EDGE_BOTH) {
105 event_mask &= ~BIT(pin);
106 writel_relaxed(event_mask,
107 chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
108 } else {
109 int_mask &= ~BIT(pin);
110 writel_relaxed(int_mask,
111 chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
112 }
113 spin_unlock_irqrestore(&chip->lock, flags);
114 gpiochip_disable_irq(gc, pin);
115 }
116
iproc_gpio_irq_set_type(struct irq_data * d,u32 type)117 static int iproc_gpio_irq_set_type(struct irq_data *d, u32 type)
118 {
119 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
120 struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
121 int pin = d->hwirq;
122 unsigned long flags;
123 u32 irq = d->irq;
124 u32 event_pol, int_pol;
125 int ret = 0;
126
127 spin_lock_irqsave(&chip->lock, flags);
128 switch (type & IRQ_TYPE_SENSE_MASK) {
129 case IRQ_TYPE_EDGE_RISING:
130 event_pol = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EDGE);
131 event_pol &= ~BIT(pin);
132 writel_relaxed(event_pol, chip->base + IPROC_GPIO_CCA_INT_EDGE);
133 break;
134 case IRQ_TYPE_EDGE_FALLING:
135 event_pol = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EDGE);
136 event_pol |= BIT(pin);
137 writel_relaxed(event_pol, chip->base + IPROC_GPIO_CCA_INT_EDGE);
138 break;
139 case IRQ_TYPE_LEVEL_HIGH:
140 int_pol = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL);
141 int_pol &= ~BIT(pin);
142 writel_relaxed(int_pol, chip->base + IPROC_GPIO_CCA_INT_LEVEL);
143 break;
144 case IRQ_TYPE_LEVEL_LOW:
145 int_pol = readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL);
146 int_pol |= BIT(pin);
147 writel_relaxed(int_pol, chip->base + IPROC_GPIO_CCA_INT_LEVEL);
148 break;
149 default:
150 /* should not come here */
151 ret = -EINVAL;
152 goto out_unlock;
153 }
154
155 if (type & IRQ_TYPE_LEVEL_MASK)
156 irq_set_handler_locked(irq_get_irq_data(irq), handle_level_irq);
157 else if (type & IRQ_TYPE_EDGE_BOTH)
158 irq_set_handler_locked(irq_get_irq_data(irq), handle_edge_irq);
159
160 out_unlock:
161 spin_unlock_irqrestore(&chip->lock, flags);
162
163 return ret;
164 }
165
iproc_gpio_irq_handler(int irq,void * data)166 static irqreturn_t iproc_gpio_irq_handler(int irq, void *data)
167 {
168 struct gpio_chip *gc = (struct gpio_chip *)data;
169 struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
170 int bit;
171 unsigned long int_bits = 0;
172 u32 int_status;
173
174 /* go through the entire GPIOs and handle all interrupts */
175 int_status = readl_relaxed(chip->intr + IPROC_CCA_INT_STS);
176 if (int_status & IPROC_CCA_INT_F_GPIOINT) {
177 u32 event, level;
178
179 /* Get level and edge interrupts */
180 event =
181 readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EVENT_MASK);
182 event &= readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_EVENT);
183 level = readl_relaxed(chip->base + IPROC_GPIO_CCA_DIN);
184 level ^= readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL);
185 level &=
186 readl_relaxed(chip->base + IPROC_GPIO_CCA_INT_LEVEL_MASK);
187 int_bits = level | event;
188
189 for_each_set_bit(bit, &int_bits, gc->ngpio)
190 generic_handle_domain_irq(gc->irq.domain, bit);
191 }
192
193 return int_bits ? IRQ_HANDLED : IRQ_NONE;
194 }
195
iproc_gpio_irq_print_chip(struct irq_data * d,struct seq_file * p)196 static void iproc_gpio_irq_print_chip(struct irq_data *d, struct seq_file *p)
197 {
198 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
199 struct iproc_gpio_chip *chip = to_iproc_gpio(gc);
200
201 seq_printf(p, dev_name(chip->dev));
202 }
203
204 static const struct irq_chip iproc_gpio_irq_chip = {
205 .irq_ack = iproc_gpio_irq_ack,
206 .irq_mask = iproc_gpio_irq_mask,
207 .irq_unmask = iproc_gpio_irq_unmask,
208 .irq_set_type = iproc_gpio_irq_set_type,
209 .irq_print_chip = iproc_gpio_irq_print_chip,
210 .flags = IRQCHIP_IMMUTABLE,
211 GPIOCHIP_IRQ_RESOURCE_HELPERS,
212 };
213
iproc_gpio_probe(struct platform_device * pdev)214 static int iproc_gpio_probe(struct platform_device *pdev)
215 {
216 struct device *dev = &pdev->dev;
217 struct device_node *dn = pdev->dev.of_node;
218 struct iproc_gpio_chip *chip;
219 u32 num_gpios;
220 int irq, ret;
221
222 chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
223 if (!chip)
224 return -ENOMEM;
225
226 chip->dev = dev;
227 platform_set_drvdata(pdev, chip);
228 spin_lock_init(&chip->lock);
229
230 chip->base = devm_platform_ioremap_resource(pdev, 0);
231 if (IS_ERR(chip->base))
232 return PTR_ERR(chip->base);
233
234 ret = bgpio_init(&chip->gc, dev, 4,
235 chip->base + IPROC_GPIO_CCA_DIN,
236 chip->base + IPROC_GPIO_CCA_DOUT,
237 NULL,
238 chip->base + IPROC_GPIO_CCA_OUT_EN,
239 NULL,
240 0);
241 if (ret) {
242 dev_err(dev, "unable to init GPIO chip\n");
243 return ret;
244 }
245
246 chip->gc.label = dev_name(dev);
247 if (!of_property_read_u32(dn, "ngpios", &num_gpios))
248 chip->gc.ngpio = num_gpios;
249
250 irq = platform_get_irq(pdev, 0);
251 if (irq > 0) {
252 struct gpio_irq_chip *girq;
253 u32 val;
254
255 chip->intr = devm_platform_ioremap_resource(pdev, 1);
256 if (IS_ERR(chip->intr))
257 return PTR_ERR(chip->intr);
258
259 /* Enable GPIO interrupts for CCA GPIO */
260 val = readl_relaxed(chip->intr + IPROC_CCA_INT_MASK);
261 val |= IPROC_CCA_INT_F_GPIOINT;
262 writel_relaxed(val, chip->intr + IPROC_CCA_INT_MASK);
263
264 /*
265 * Directly request the irq here instead of passing
266 * a flow-handler because the irq is shared.
267 */
268 ret = devm_request_irq(dev, irq, iproc_gpio_irq_handler,
269 IRQF_SHARED, chip->gc.label, &chip->gc);
270 if (ret) {
271 dev_err(dev, "Fail to request IRQ%d: %d\n", irq, ret);
272 return ret;
273 }
274
275 girq = &chip->gc.irq;
276 gpio_irq_chip_set_chip(girq, &iproc_gpio_irq_chip);
277 /* This will let us handle the parent IRQ in the driver */
278 girq->parent_handler = NULL;
279 girq->num_parents = 0;
280 girq->parents = NULL;
281 girq->default_type = IRQ_TYPE_NONE;
282 girq->handler = handle_simple_irq;
283 }
284
285 ret = devm_gpiochip_add_data(dev, &chip->gc, chip);
286 if (ret) {
287 dev_err(dev, "unable to add GPIO chip\n");
288 return ret;
289 }
290
291 return 0;
292 }
293
iproc_gpio_remove(struct platform_device * pdev)294 static void iproc_gpio_remove(struct platform_device *pdev)
295 {
296 struct iproc_gpio_chip *chip = platform_get_drvdata(pdev);
297
298 if (chip->intr) {
299 u32 val;
300
301 val = readl_relaxed(chip->intr + IPROC_CCA_INT_MASK);
302 val &= ~IPROC_CCA_INT_F_GPIOINT;
303 writel_relaxed(val, chip->intr + IPROC_CCA_INT_MASK);
304 }
305 }
306
307 static const struct of_device_id bcm_iproc_gpio_of_match[] = {
308 { .compatible = "brcm,iproc-gpio-cca" },
309 {}
310 };
311 MODULE_DEVICE_TABLE(of, bcm_iproc_gpio_of_match);
312
313 static struct platform_driver bcm_iproc_gpio_driver = {
314 .driver = {
315 .name = "iproc-xgs-gpio",
316 .of_match_table = bcm_iproc_gpio_of_match,
317 },
318 .probe = iproc_gpio_probe,
319 .remove_new = iproc_gpio_remove,
320 };
321
322 module_platform_driver(bcm_iproc_gpio_driver);
323
324 MODULE_DESCRIPTION("XGS IPROC GPIO driver");
325 MODULE_LICENSE("GPL v2");
326