1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * RDA Micro GPIO driver
4 *
5 * Copyright (C) 2012 RDA Micro Inc.
6 * Copyright (C) 2019 Manivannan Sadhasivam
7 */
8
9 #include <linux/bitops.h>
10 #include <linux/gpio/driver.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 RDA_GPIO_OEN_VAL 0x00
17 #define RDA_GPIO_OEN_SET_OUT 0x04
18 #define RDA_GPIO_OEN_SET_IN 0x08
19 #define RDA_GPIO_VAL 0x0c
20 #define RDA_GPIO_SET 0x10
21 #define RDA_GPIO_CLR 0x14
22 #define RDA_GPIO_INT_CTRL_SET 0x18
23 #define RDA_GPIO_INT_CTRL_CLR 0x1c
24 #define RDA_GPIO_INT_CLR 0x20
25 #define RDA_GPIO_INT_STATUS 0x24
26
27 #define RDA_GPIO_IRQ_RISE_SHIFT 0
28 #define RDA_GPIO_IRQ_FALL_SHIFT 8
29 #define RDA_GPIO_DEBOUCE_SHIFT 16
30 #define RDA_GPIO_LEVEL_SHIFT 24
31
32 #define RDA_GPIO_IRQ_MASK 0xff
33
34 /* Each bank consists of 32 GPIOs */
35 #define RDA_GPIO_BANK_NR 32
36
37 struct rda_gpio {
38 struct gpio_chip chip;
39 void __iomem *base;
40 spinlock_t lock;
41 struct irq_chip irq_chip;
42 int irq;
43 };
44
rda_gpio_update(struct gpio_chip * chip,unsigned int offset,u16 reg,int val)45 static inline void rda_gpio_update(struct gpio_chip *chip, unsigned int offset,
46 u16 reg, int val)
47 {
48 struct rda_gpio *rda_gpio = gpiochip_get_data(chip);
49 void __iomem *base = rda_gpio->base;
50 unsigned long flags;
51 u32 tmp;
52
53 spin_lock_irqsave(&rda_gpio->lock, flags);
54 tmp = readl_relaxed(base + reg);
55
56 if (val)
57 tmp |= BIT(offset);
58 else
59 tmp &= ~BIT(offset);
60
61 writel_relaxed(tmp, base + reg);
62 spin_unlock_irqrestore(&rda_gpio->lock, flags);
63 }
64
rda_gpio_irq_mask(struct irq_data * data)65 static void rda_gpio_irq_mask(struct irq_data *data)
66 {
67 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
68 struct rda_gpio *rda_gpio = gpiochip_get_data(chip);
69 void __iomem *base = rda_gpio->base;
70 u32 offset = irqd_to_hwirq(data);
71 u32 value;
72
73 value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT;
74 value |= BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT;
75
76 writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR);
77 }
78
rda_gpio_irq_ack(struct irq_data * data)79 static void rda_gpio_irq_ack(struct irq_data *data)
80 {
81 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
82 u32 offset = irqd_to_hwirq(data);
83
84 rda_gpio_update(chip, offset, RDA_GPIO_INT_CLR, 1);
85 }
86
rda_gpio_set_irq(struct gpio_chip * chip,u32 offset,unsigned int flow_type)87 static int rda_gpio_set_irq(struct gpio_chip *chip, u32 offset,
88 unsigned int flow_type)
89 {
90 struct rda_gpio *rda_gpio = gpiochip_get_data(chip);
91 void __iomem *base = rda_gpio->base;
92 u32 value;
93
94 switch (flow_type) {
95 case IRQ_TYPE_EDGE_RISING:
96 /* Set rising edge trigger */
97 value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT;
98 writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);
99
100 /* Switch to edge trigger interrupt */
101 value = BIT(offset) << RDA_GPIO_LEVEL_SHIFT;
102 writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR);
103 break;
104
105 case IRQ_TYPE_EDGE_FALLING:
106 /* Set falling edge trigger */
107 value = BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT;
108 writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);
109
110 /* Switch to edge trigger interrupt */
111 value = BIT(offset) << RDA_GPIO_LEVEL_SHIFT;
112 writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR);
113 break;
114
115 case IRQ_TYPE_EDGE_BOTH:
116 /* Set both edge trigger */
117 value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT;
118 value |= BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT;
119 writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);
120
121 /* Switch to edge trigger interrupt */
122 value = BIT(offset) << RDA_GPIO_LEVEL_SHIFT;
123 writel_relaxed(value, base + RDA_GPIO_INT_CTRL_CLR);
124 break;
125
126 case IRQ_TYPE_LEVEL_HIGH:
127 /* Set high level trigger */
128 value = BIT(offset) << RDA_GPIO_IRQ_RISE_SHIFT;
129
130 /* Switch to level trigger interrupt */
131 value |= BIT(offset) << RDA_GPIO_LEVEL_SHIFT;
132 writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);
133 break;
134
135 case IRQ_TYPE_LEVEL_LOW:
136 /* Set low level trigger */
137 value = BIT(offset) << RDA_GPIO_IRQ_FALL_SHIFT;
138
139 /* Switch to level trigger interrupt */
140 value |= BIT(offset) << RDA_GPIO_LEVEL_SHIFT;
141 writel_relaxed(value, base + RDA_GPIO_INT_CTRL_SET);
142 break;
143
144 default:
145 return -EINVAL;
146 }
147
148 return 0;
149 }
150
rda_gpio_irq_unmask(struct irq_data * data)151 static void rda_gpio_irq_unmask(struct irq_data *data)
152 {
153 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
154 u32 offset = irqd_to_hwirq(data);
155 u32 trigger = irqd_get_trigger_type(data);
156
157 rda_gpio_set_irq(chip, offset, trigger);
158 }
159
rda_gpio_irq_set_type(struct irq_data * data,unsigned int flow_type)160 static int rda_gpio_irq_set_type(struct irq_data *data, unsigned int flow_type)
161 {
162 struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
163 u32 offset = irqd_to_hwirq(data);
164 int ret;
165
166 ret = rda_gpio_set_irq(chip, offset, flow_type);
167 if (ret)
168 return ret;
169
170 if (flow_type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
171 irq_set_handler_locked(data, handle_level_irq);
172 else if (flow_type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
173 irq_set_handler_locked(data, handle_edge_irq);
174
175 return 0;
176 }
177
rda_gpio_irq_handler(struct irq_desc * desc)178 static void rda_gpio_irq_handler(struct irq_desc *desc)
179 {
180 struct gpio_chip *chip = irq_desc_get_handler_data(desc);
181 struct irq_chip *ic = irq_desc_get_chip(desc);
182 struct rda_gpio *rda_gpio = gpiochip_get_data(chip);
183 unsigned long status;
184 u32 n, girq;
185
186 chained_irq_enter(ic, desc);
187
188 status = readl_relaxed(rda_gpio->base + RDA_GPIO_INT_STATUS);
189 /* Only lower 8 bits are capable of generating interrupts */
190 status &= RDA_GPIO_IRQ_MASK;
191
192 for_each_set_bit(n, &status, RDA_GPIO_BANK_NR) {
193 girq = irq_find_mapping(chip->irq.domain, n);
194 generic_handle_irq(girq);
195 }
196
197 chained_irq_exit(ic, desc);
198 }
199
rda_gpio_probe(struct platform_device * pdev)200 static int rda_gpio_probe(struct platform_device *pdev)
201 {
202 struct device_node *np = pdev->dev.of_node;
203 struct device *dev = &pdev->dev;
204 struct gpio_irq_chip *girq;
205 struct rda_gpio *rda_gpio;
206 u32 ngpios;
207 int ret;
208
209 rda_gpio = devm_kzalloc(dev, sizeof(*rda_gpio), GFP_KERNEL);
210 if (!rda_gpio)
211 return -ENOMEM;
212
213 ret = device_property_read_u32(dev, "ngpios", &ngpios);
214 if (ret < 0)
215 return ret;
216
217 /*
218 * Not all ports have interrupt capability. For instance, on
219 * RDA8810PL, GPIOC doesn't support interrupt. So we must handle
220 * those also.
221 */
222 rda_gpio->irq = platform_get_irq(pdev, 0);
223
224 rda_gpio->base = devm_platform_ioremap_resource(pdev, 0);
225 if (IS_ERR(rda_gpio->base))
226 return PTR_ERR(rda_gpio->base);
227
228 spin_lock_init(&rda_gpio->lock);
229
230 ret = bgpio_init(&rda_gpio->chip, dev, 4,
231 rda_gpio->base + RDA_GPIO_VAL,
232 rda_gpio->base + RDA_GPIO_SET,
233 rda_gpio->base + RDA_GPIO_CLR,
234 rda_gpio->base + RDA_GPIO_OEN_SET_OUT,
235 rda_gpio->base + RDA_GPIO_OEN_SET_IN,
236 BGPIOF_READ_OUTPUT_REG_SET);
237 if (ret) {
238 dev_err(dev, "bgpio_init failed\n");
239 return ret;
240 }
241
242 rda_gpio->chip.label = dev_name(dev);
243 rda_gpio->chip.ngpio = ngpios;
244 rda_gpio->chip.base = -1;
245 rda_gpio->chip.parent = dev;
246 rda_gpio->chip.of_node = np;
247
248 if (rda_gpio->irq >= 0) {
249 rda_gpio->irq_chip.name = "rda-gpio",
250 rda_gpio->irq_chip.irq_ack = rda_gpio_irq_ack,
251 rda_gpio->irq_chip.irq_mask = rda_gpio_irq_mask,
252 rda_gpio->irq_chip.irq_unmask = rda_gpio_irq_unmask,
253 rda_gpio->irq_chip.irq_set_type = rda_gpio_irq_set_type,
254 rda_gpio->irq_chip.flags = IRQCHIP_SKIP_SET_WAKE,
255
256 girq = &rda_gpio->chip.irq;
257 girq->chip = &rda_gpio->irq_chip;
258 girq->handler = handle_bad_irq;
259 girq->default_type = IRQ_TYPE_NONE;
260 girq->parent_handler = rda_gpio_irq_handler;
261 girq->parent_handler_data = rda_gpio;
262 girq->num_parents = 1;
263 girq->parents = devm_kcalloc(dev, 1,
264 sizeof(*girq->parents),
265 GFP_KERNEL);
266 if (!girq->parents)
267 return -ENOMEM;
268 girq->parents[0] = rda_gpio->irq;
269 }
270
271 platform_set_drvdata(pdev, rda_gpio);
272
273 return devm_gpiochip_add_data(dev, &rda_gpio->chip, rda_gpio);
274 }
275
276 static const struct of_device_id rda_gpio_of_match[] = {
277 { .compatible = "rda,8810pl-gpio", },
278 { /* sentinel */ }
279 };
280 MODULE_DEVICE_TABLE(of, rda_gpio_of_match);
281
282 static struct platform_driver rda_gpio_driver = {
283 .probe = rda_gpio_probe,
284 .driver = {
285 .name = "rda-gpio",
286 .of_match_table = rda_gpio_of_match,
287 },
288 };
289
290 module_platform_driver_probe(rda_gpio_driver, rda_gpio_probe);
291
292 MODULE_DESCRIPTION("RDA Micro GPIO driver");
293 MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
294 MODULE_LICENSE("GPL v2");
295