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11#include <linux/spinlock.h>
12#include <linux/errno.h>
13#include <linux/init.h>
14#include <linux/io.h>
15#include <linux/ioport.h>
16#include <linux/interrupt.h>
17#include <linux/irq.h>
18#include <linux/irqchip/chained_irq.h>
19#include <linux/module.h>
20#include <linux/bitops.h>
21#include <linux/gpio/driver.h>
22#include <linux/device.h>
23#include <linux/amba/bus.h>
24#include <linux/slab.h>
25#include <linux/pinctrl/consumer.h>
26#include <linux/pm.h>
27
28#define GPIODIR 0x400
29#define GPIOIS 0x404
30#define GPIOIBE 0x408
31#define GPIOIEV 0x40C
32#define GPIOIE 0x410
33#define GPIORIS 0x414
34#define GPIOMIS 0x418
35#define GPIOIC 0x41C
36
37#define PL061_GPIO_NR 8
38
39#ifdef CONFIG_PM
40struct pl061_context_save_regs {
41 u8 gpio_data;
42 u8 gpio_dir;
43 u8 gpio_is;
44 u8 gpio_ibe;
45 u8 gpio_iev;
46 u8 gpio_ie;
47};
48#endif
49
50struct pl061 {
51 raw_spinlock_t lock;
52
53 void __iomem *base;
54 struct gpio_chip gc;
55 struct irq_chip irq_chip;
56 int parent_irq;
57
58#ifdef CONFIG_PM
59 struct pl061_context_save_regs csave_regs;
60#endif
61};
62
63static int pl061_get_direction(struct gpio_chip *gc, unsigned offset)
64{
65 struct pl061 *pl061 = gpiochip_get_data(gc);
66
67 if (readb(pl061->base + GPIODIR) & BIT(offset))
68 return GPIO_LINE_DIRECTION_OUT;
69
70 return GPIO_LINE_DIRECTION_IN;
71}
72
73static int pl061_direction_input(struct gpio_chip *gc, unsigned offset)
74{
75 struct pl061 *pl061 = gpiochip_get_data(gc);
76 unsigned long flags;
77 unsigned char gpiodir;
78
79 raw_spin_lock_irqsave(&pl061->lock, flags);
80 gpiodir = readb(pl061->base + GPIODIR);
81 gpiodir &= ~(BIT(offset));
82 writeb(gpiodir, pl061->base + GPIODIR);
83 raw_spin_unlock_irqrestore(&pl061->lock, flags);
84
85 return 0;
86}
87
88static int pl061_direction_output(struct gpio_chip *gc, unsigned offset,
89 int value)
90{
91 struct pl061 *pl061 = gpiochip_get_data(gc);
92 unsigned long flags;
93 unsigned char gpiodir;
94
95 raw_spin_lock_irqsave(&pl061->lock, flags);
96 writeb(!!value << offset, pl061->base + (BIT(offset + 2)));
97 gpiodir = readb(pl061->base + GPIODIR);
98 gpiodir |= BIT(offset);
99 writeb(gpiodir, pl061->base + GPIODIR);
100
101
102
103
104
105 writeb(!!value << offset, pl061->base + (BIT(offset + 2)));
106 raw_spin_unlock_irqrestore(&pl061->lock, flags);
107
108 return 0;
109}
110
111static int pl061_get_value(struct gpio_chip *gc, unsigned offset)
112{
113 struct pl061 *pl061 = gpiochip_get_data(gc);
114
115 return !!readb(pl061->base + (BIT(offset + 2)));
116}
117
118static void pl061_set_value(struct gpio_chip *gc, unsigned offset, int value)
119{
120 struct pl061 *pl061 = gpiochip_get_data(gc);
121
122 writeb(!!value << offset, pl061->base + (BIT(offset + 2)));
123}
124
125static int pl061_irq_type(struct irq_data *d, unsigned trigger)
126{
127 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
128 struct pl061 *pl061 = gpiochip_get_data(gc);
129 int offset = irqd_to_hwirq(d);
130 unsigned long flags;
131 u8 gpiois, gpioibe, gpioiev;
132 u8 bit = BIT(offset);
133
134 if (offset < 0 || offset >= PL061_GPIO_NR)
135 return -EINVAL;
136
137 if ((trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) &&
138 (trigger & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING)))
139 {
140 dev_err(gc->parent,
141 "trying to configure line %d for both level and edge "
142 "detection, choose one!\n",
143 offset);
144 return -EINVAL;
145 }
146
147
148 raw_spin_lock_irqsave(&pl061->lock, flags);
149
150 gpioiev = readb(pl061->base + GPIOIEV);
151 gpiois = readb(pl061->base + GPIOIS);
152 gpioibe = readb(pl061->base + GPIOIBE);
153
154 if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
155 bool polarity = trigger & IRQ_TYPE_LEVEL_HIGH;
156
157
158 gpioibe &= ~bit;
159
160 gpiois |= bit;
161
162 if (polarity)
163 gpioiev |= bit;
164 else
165 gpioiev &= ~bit;
166 irq_set_handler_locked(d, handle_level_irq);
167 dev_dbg(gc->parent, "line %d: IRQ on %s level\n",
168 offset,
169 polarity ? "HIGH" : "LOW");
170 } else if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
171
172 gpiois &= ~bit;
173
174 gpioibe |= bit;
175 irq_set_handler_locked(d, handle_edge_irq);
176 dev_dbg(gc->parent, "line %d: IRQ on both edges\n", offset);
177 } else if ((trigger & IRQ_TYPE_EDGE_RISING) ||
178 (trigger & IRQ_TYPE_EDGE_FALLING)) {
179 bool rising = trigger & IRQ_TYPE_EDGE_RISING;
180
181
182 gpiois &= ~bit;
183
184 gpioibe &= ~bit;
185
186 if (rising)
187 gpioiev |= bit;
188 else
189 gpioiev &= ~bit;
190 irq_set_handler_locked(d, handle_edge_irq);
191 dev_dbg(gc->parent, "line %d: IRQ on %s edge\n",
192 offset,
193 rising ? "RISING" : "FALLING");
194 } else {
195
196 gpiois &= ~bit;
197 gpioibe &= ~bit;
198 gpioiev &= ~bit;
199 irq_set_handler_locked(d, handle_bad_irq);
200 dev_warn(gc->parent, "no trigger selected for line %d\n",
201 offset);
202 }
203
204 writeb(gpiois, pl061->base + GPIOIS);
205 writeb(gpioibe, pl061->base + GPIOIBE);
206 writeb(gpioiev, pl061->base + GPIOIEV);
207
208 raw_spin_unlock_irqrestore(&pl061->lock, flags);
209
210 return 0;
211}
212
213static void pl061_irq_handler(struct irq_desc *desc)
214{
215 unsigned long pending;
216 int offset;
217 struct gpio_chip *gc = irq_desc_get_handler_data(desc);
218 struct pl061 *pl061 = gpiochip_get_data(gc);
219 struct irq_chip *irqchip = irq_desc_get_chip(desc);
220
221 chained_irq_enter(irqchip, desc);
222
223 pending = readb(pl061->base + GPIOMIS);
224 if (pending) {
225 for_each_set_bit(offset, &pending, PL061_GPIO_NR)
226 generic_handle_irq(irq_find_mapping(gc->irq.domain,
227 offset));
228 }
229
230 chained_irq_exit(irqchip, desc);
231}
232
233static void pl061_irq_mask(struct irq_data *d)
234{
235 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
236 struct pl061 *pl061 = gpiochip_get_data(gc);
237 u8 mask = BIT(irqd_to_hwirq(d) % PL061_GPIO_NR);
238 u8 gpioie;
239
240 raw_spin_lock(&pl061->lock);
241 gpioie = readb(pl061->base + GPIOIE) & ~mask;
242 writeb(gpioie, pl061->base + GPIOIE);
243 raw_spin_unlock(&pl061->lock);
244}
245
246static void pl061_irq_unmask(struct irq_data *d)
247{
248 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
249 struct pl061 *pl061 = gpiochip_get_data(gc);
250 u8 mask = BIT(irqd_to_hwirq(d) % PL061_GPIO_NR);
251 u8 gpioie;
252
253 raw_spin_lock(&pl061->lock);
254 gpioie = readb(pl061->base + GPIOIE) | mask;
255 writeb(gpioie, pl061->base + GPIOIE);
256 raw_spin_unlock(&pl061->lock);
257}
258
259
260
261
262
263
264
265
266
267static void pl061_irq_ack(struct irq_data *d)
268{
269 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
270 struct pl061 *pl061 = gpiochip_get_data(gc);
271 u8 mask = BIT(irqd_to_hwirq(d) % PL061_GPIO_NR);
272
273 raw_spin_lock(&pl061->lock);
274 writeb(mask, pl061->base + GPIOIC);
275 raw_spin_unlock(&pl061->lock);
276}
277
278static int pl061_irq_set_wake(struct irq_data *d, unsigned int state)
279{
280 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
281 struct pl061 *pl061 = gpiochip_get_data(gc);
282
283 return irq_set_irq_wake(pl061->parent_irq, state);
284}
285
286static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
287{
288 struct device *dev = &adev->dev;
289 struct pl061 *pl061;
290 struct gpio_irq_chip *girq;
291 int ret, irq;
292
293 pl061 = devm_kzalloc(dev, sizeof(*pl061), GFP_KERNEL);
294 if (pl061 == NULL)
295 return -ENOMEM;
296
297 pl061->base = devm_ioremap_resource(dev, &adev->res);
298 if (IS_ERR(pl061->base))
299 return PTR_ERR(pl061->base);
300
301 raw_spin_lock_init(&pl061->lock);
302 pl061->gc.request = gpiochip_generic_request;
303 pl061->gc.free = gpiochip_generic_free;
304 pl061->gc.base = -1;
305 pl061->gc.get_direction = pl061_get_direction;
306 pl061->gc.direction_input = pl061_direction_input;
307 pl061->gc.direction_output = pl061_direction_output;
308 pl061->gc.get = pl061_get_value;
309 pl061->gc.set = pl061_set_value;
310 pl061->gc.ngpio = PL061_GPIO_NR;
311 pl061->gc.label = dev_name(dev);
312 pl061->gc.parent = dev;
313 pl061->gc.owner = THIS_MODULE;
314
315
316
317
318 pl061->irq_chip.name = dev_name(dev);
319 pl061->irq_chip.irq_ack = pl061_irq_ack;
320 pl061->irq_chip.irq_mask = pl061_irq_mask;
321 pl061->irq_chip.irq_unmask = pl061_irq_unmask;
322 pl061->irq_chip.irq_set_type = pl061_irq_type;
323 pl061->irq_chip.irq_set_wake = pl061_irq_set_wake;
324
325 writeb(0, pl061->base + GPIOIE);
326 irq = adev->irq[0];
327 if (!irq)
328 dev_warn(&adev->dev, "IRQ support disabled\n");
329 pl061->parent_irq = irq;
330
331 girq = &pl061->gc.irq;
332 girq->chip = &pl061->irq_chip;
333 girq->parent_handler = pl061_irq_handler;
334 girq->num_parents = 1;
335 girq->parents = devm_kcalloc(dev, 1, sizeof(*girq->parents),
336 GFP_KERNEL);
337 if (!girq->parents)
338 return -ENOMEM;
339 girq->parents[0] = irq;
340 girq->default_type = IRQ_TYPE_NONE;
341 girq->handler = handle_bad_irq;
342
343 ret = devm_gpiochip_add_data(dev, &pl061->gc, pl061);
344 if (ret)
345 return ret;
346
347 amba_set_drvdata(adev, pl061);
348 dev_info(dev, "PL061 GPIO chip registered\n");
349
350 return 0;
351}
352
353#ifdef CONFIG_PM
354static int pl061_suspend(struct device *dev)
355{
356 struct pl061 *pl061 = dev_get_drvdata(dev);
357 int offset;
358
359 pl061->csave_regs.gpio_data = 0;
360 pl061->csave_regs.gpio_dir = readb(pl061->base + GPIODIR);
361 pl061->csave_regs.gpio_is = readb(pl061->base + GPIOIS);
362 pl061->csave_regs.gpio_ibe = readb(pl061->base + GPIOIBE);
363 pl061->csave_regs.gpio_iev = readb(pl061->base + GPIOIEV);
364 pl061->csave_regs.gpio_ie = readb(pl061->base + GPIOIE);
365
366 for (offset = 0; offset < PL061_GPIO_NR; offset++) {
367 if (pl061->csave_regs.gpio_dir & (BIT(offset)))
368 pl061->csave_regs.gpio_data |=
369 pl061_get_value(&pl061->gc, offset) << offset;
370 }
371
372 return 0;
373}
374
375static int pl061_resume(struct device *dev)
376{
377 struct pl061 *pl061 = dev_get_drvdata(dev);
378 int offset;
379
380 for (offset = 0; offset < PL061_GPIO_NR; offset++) {
381 if (pl061->csave_regs.gpio_dir & (BIT(offset)))
382 pl061_direction_output(&pl061->gc, offset,
383 pl061->csave_regs.gpio_data &
384 (BIT(offset)));
385 else
386 pl061_direction_input(&pl061->gc, offset);
387 }
388
389 writeb(pl061->csave_regs.gpio_is, pl061->base + GPIOIS);
390 writeb(pl061->csave_regs.gpio_ibe, pl061->base + GPIOIBE);
391 writeb(pl061->csave_regs.gpio_iev, pl061->base + GPIOIEV);
392 writeb(pl061->csave_regs.gpio_ie, pl061->base + GPIOIE);
393
394 return 0;
395}
396
397static const struct dev_pm_ops pl061_dev_pm_ops = {
398 .suspend = pl061_suspend,
399 .resume = pl061_resume,
400 .freeze = pl061_suspend,
401 .restore = pl061_resume,
402};
403#endif
404
405static const struct amba_id pl061_ids[] = {
406 {
407 .id = 0x00041061,
408 .mask = 0x000fffff,
409 },
410 { 0, 0 },
411};
412MODULE_DEVICE_TABLE(amba, pl061_ids);
413
414static struct amba_driver pl061_gpio_driver = {
415 .drv = {
416 .name = "pl061_gpio",
417#ifdef CONFIG_PM
418 .pm = &pl061_dev_pm_ops,
419#endif
420 },
421 .id_table = pl061_ids,
422 .probe = pl061_probe,
423};
424module_amba_driver(pl061_gpio_driver);
425
426MODULE_LICENSE("GPL v2");
427
