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1/*
2 * Copyright (C) 2011-2012 Avionic Design GmbH
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8
9#include <linux/gpio.h>
10#include <linux/i2c.h>
11#include <linux/interrupt.h>
12#include <linux/irqdomain.h>
13#include <linux/module.h>
14#include <linux/of_irq.h>
15#include <linux/seq_file.h>
16#include <linux/slab.h>
17
18#define GPIO_DDR(gpio) (0x00 << (gpio)->reg_shift)
19#define GPIO_PLR(gpio) (0x01 << (gpio)->reg_shift)
20#define GPIO_IER(gpio) (0x02 << (gpio)->reg_shift)
21#define GPIO_ISR(gpio) (0x03 << (gpio)->reg_shift)
22#define GPIO_PTR(gpio) (0x04 << (gpio)->reg_shift)
23
24struct adnp {
25 struct i2c_client *client;
26 struct gpio_chip gpio;
27 unsigned int reg_shift;
28
29 struct mutex i2c_lock;
30
31 struct irq_domain *domain;
32 struct mutex irq_lock;
33
34 u8 *irq_enable;
35 u8 *irq_level;
36 u8 *irq_rise;
37 u8 *irq_fall;
38 u8 *irq_high;
39 u8 *irq_low;
40};
41
42static inline struct adnp *to_adnp(struct gpio_chip *chip)
43{
44 return container_of(chip, struct adnp, gpio);
45}
46
47static int adnp_read(struct adnp *adnp, unsigned offset, uint8_t *value)
48{
49 int err;
50
51 err = i2c_smbus_read_byte_data(adnp->client, offset);
52 if (err < 0) {
53 dev_err(adnp->gpio.dev, "%s failed: %d\n",
54 "i2c_smbus_read_byte_data()", err);
55 return err;
56 }
57
58 *value = err;
59 return 0;
60}
61
62static int adnp_write(struct adnp *adnp, unsigned offset, uint8_t value)
63{
64 int err;
65
66 err = i2c_smbus_write_byte_data(adnp->client, offset, value);
67 if (err < 0) {
68 dev_err(adnp->gpio.dev, "%s failed: %d\n",
69 "i2c_smbus_write_byte_data()", err);
70 return err;
71 }
72
73 return 0;
74}
75
76static int adnp_gpio_get(struct gpio_chip *chip, unsigned offset)
77{
78 struct adnp *adnp = to_adnp(chip);
79 unsigned int reg = offset >> adnp->reg_shift;
80 unsigned int pos = offset & 7;
81 u8 value;
82 int err;
83
84 err = adnp_read(adnp, GPIO_PLR(adnp) + reg, &value);
85 if (err < 0)
86 return err;
87
88 return (value & BIT(pos)) ? 1 : 0;
89}
90
91static void __adnp_gpio_set(struct adnp *adnp, unsigned offset, int value)
92{
93 unsigned int reg = offset >> adnp->reg_shift;
94 unsigned int pos = offset & 7;
95 int err;
96 u8 val;
97
98 err = adnp_read(adnp, GPIO_PLR(adnp) + reg, &val);
99 if (err < 0)
100 return;
101
102 if (value)
103 val |= BIT(pos);
104 else
105 val &= ~BIT(pos);
106
107 adnp_write(adnp, GPIO_PLR(adnp) + reg, val);
108}
109
110static void adnp_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
111{
112 struct adnp *adnp = to_adnp(chip);
113
114 mutex_lock(&adnp->i2c_lock);
115 __adnp_gpio_set(adnp, offset, value);
116 mutex_unlock(&adnp->i2c_lock);
117}
118
119static int adnp_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
120{
121 struct adnp *adnp = to_adnp(chip);
122 unsigned int reg = offset >> adnp->reg_shift;
123 unsigned int pos = offset & 7;
124 u8 value;
125 int err;
126
127 mutex_lock(&adnp->i2c_lock);
128
129 err = adnp_read(adnp, GPIO_DDR(adnp) + reg, &value);
130 if (err < 0)
131 goto out;
132
133 value &= ~BIT(pos);
134
135 err = adnp_write(adnp, GPIO_DDR(adnp) + reg, value);
136 if (err < 0)
137 goto out;
138
139 err = adnp_read(adnp, GPIO_DDR(adnp) + reg, &value);
140 if (err < 0)
141 goto out;
142
143 if (err & BIT(pos))
144 err = -EACCES;
145
146 err = 0;
147
148out:
149 mutex_unlock(&adnp->i2c_lock);
150 return err;
151}
152
153static int adnp_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
154 int value)
155{
156 struct adnp *adnp = to_adnp(chip);
157 unsigned int reg = offset >> adnp->reg_shift;
158 unsigned int pos = offset & 7;
159 int err;
160 u8 val;
161
162 mutex_lock(&adnp->i2c_lock);
163
164 err = adnp_read(adnp, GPIO_DDR(adnp) + reg, &val);
165 if (err < 0)
166 goto out;
167
168 val |= BIT(pos);
169
170 err = adnp_write(adnp, GPIO_DDR(adnp) + reg, val);
171 if (err < 0)
172 goto out;
173
174 err = adnp_read(adnp, GPIO_DDR(adnp) + reg, &val);
175 if (err < 0)
176 goto out;
177
178 if (!(val & BIT(pos))) {
179 err = -EPERM;
180 goto out;
181 }
182
183 __adnp_gpio_set(adnp, offset, value);
184 err = 0;
185
186out:
187 mutex_unlock(&adnp->i2c_lock);
188 return err;
189}
190
191static void adnp_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
192{
193 struct adnp *adnp = to_adnp(chip);
194 unsigned int num_regs = 1 << adnp->reg_shift, i, j;
195 int err;
196
197 for (i = 0; i < num_regs; i++) {
198 u8 ddr, plr, ier, isr;
199
200 mutex_lock(&adnp->i2c_lock);
201
202 err = adnp_read(adnp, GPIO_DDR(adnp) + i, &ddr);
203 if (err < 0) {
204 mutex_unlock(&adnp->i2c_lock);
205 return;
206 }
207
208 err = adnp_read(adnp, GPIO_PLR(adnp) + i, &plr);
209 if (err < 0) {
210 mutex_unlock(&adnp->i2c_lock);
211 return;
212 }
213
214 err = adnp_read(adnp, GPIO_IER(adnp) + i, &ier);
215 if (err < 0) {
216 mutex_unlock(&adnp->i2c_lock);
217 return;
218 }
219
220 err = adnp_read(adnp, GPIO_ISR(adnp) + i, &isr);
221 if (err < 0) {
222 mutex_unlock(&adnp->i2c_lock);
223 return;
224 }
225
226 mutex_unlock(&adnp->i2c_lock);
227
228 for (j = 0; j < 8; j++) {
229 unsigned int bit = (i << adnp->reg_shift) + j;
230 const char *direction = "input ";
231 const char *level = "low ";
232 const char *interrupt = "disabled";
233 const char *pending = "";
234
235 if (ddr & BIT(j))
236 direction = "output";
237
238 if (plr & BIT(j))
239 level = "high";
240
241 if (ier & BIT(j))
242 interrupt = "enabled ";
243
244 if (isr & BIT(j))
245 pending = "pending";
246
247 seq_printf(s, "%2u: %s %s IRQ %s %s\n", bit,
248 direction, level, interrupt, pending);
249 }
250 }
251}
252
253static int adnp_gpio_setup(struct adnp *adnp, unsigned int num_gpios)
254{
255 struct gpio_chip *chip = &adnp->gpio;
256
257 adnp->reg_shift = get_count_order(num_gpios) - 3;
258
259 chip->direction_input = adnp_gpio_direction_input;
260 chip->direction_output = adnp_gpio_direction_output;
261 chip->get = adnp_gpio_get;
262 chip->set = adnp_gpio_set;
263 chip->can_sleep = true;
264
265 if (IS_ENABLED(CONFIG_DEBUG_FS))
266 chip->dbg_show = adnp_gpio_dbg_show;
267
268 chip->base = -1;
269 chip->ngpio = num_gpios;
270 chip->label = adnp->client->name;
271 chip->dev = &adnp->client->dev;
272 chip->of_node = chip->dev->of_node;
273 chip->owner = THIS_MODULE;
274
275 return 0;
276}
277
278static irqreturn_t adnp_irq(int irq, void *data)
279{
280 struct adnp *adnp = data;
281 unsigned int num_regs, i;
282
283 num_regs = 1 << adnp->reg_shift;
284
285 for (i = 0; i < num_regs; i++) {
286 unsigned int base = i << adnp->reg_shift, bit;
287 u8 changed, level, isr, ier;
288 unsigned long pending;
289 int err;
290
291 mutex_lock(&adnp->i2c_lock);
292
293 err = adnp_read(adnp, GPIO_PLR(adnp) + i, &level);
294 if (err < 0) {
295 mutex_unlock(&adnp->i2c_lock);
296 continue;
297 }
298
299 err = adnp_read(adnp, GPIO_ISR(adnp) + i, &isr);
300 if (err < 0) {
301 mutex_unlock(&adnp->i2c_lock);
302 continue;
303 }
304
305 err = adnp_read(adnp, GPIO_IER(adnp) + i, &ier);
306 if (err < 0) {
307 mutex_unlock(&adnp->i2c_lock);
308 continue;
309 }
310
311 mutex_unlock(&adnp->i2c_lock);
312
313 /* determine pins that changed levels */
314 changed = level ^ adnp->irq_level[i];
315
316 /* compute edge-triggered interrupts */
317 pending = changed & ((adnp->irq_fall[i] & ~level) |
318 (adnp->irq_rise[i] & level));
319
320 /* add in level-triggered interrupts */
321 pending |= (adnp->irq_high[i] & level) |
322 (adnp->irq_low[i] & ~level);
323
324 /* mask out non-pending and disabled interrupts */
325 pending &= isr & ier;
326
327 for_each_set_bit(bit, &pending, 8) {
328 unsigned int child_irq;
329 child_irq = irq_find_mapping(adnp->domain, base + bit);
330 handle_nested_irq(child_irq);
331 }
332 }
333
334 return IRQ_HANDLED;
335}
336
337static int adnp_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
338{
339 struct adnp *adnp = to_adnp(chip);
340 return irq_create_mapping(adnp->domain, offset);
341}
342
343static void adnp_irq_mask(struct irq_data *data)
344{
345 struct adnp *adnp = irq_data_get_irq_chip_data(data);
346 unsigned int reg = data->hwirq >> adnp->reg_shift;
347 unsigned int pos = data->hwirq & 7;
348
349 adnp->irq_enable[reg] &= ~BIT(pos);
350}
351
352static void adnp_irq_unmask(struct irq_data *data)
353{
354 struct adnp *adnp = irq_data_get_irq_chip_data(data);
355 unsigned int reg = data->hwirq >> adnp->reg_shift;
356 unsigned int pos = data->hwirq & 7;
357
358 adnp->irq_enable[reg] |= BIT(pos);
359}
360
361static int adnp_irq_set_type(struct irq_data *data, unsigned int type)
362{
363 struct adnp *adnp = irq_data_get_irq_chip_data(data);
364 unsigned int reg = data->hwirq >> adnp->reg_shift;
365 unsigned int pos = data->hwirq & 7;
366
367 if (type & IRQ_TYPE_EDGE_RISING)
368 adnp->irq_rise[reg] |= BIT(pos);
369 else
370 adnp->irq_rise[reg] &= ~BIT(pos);
371
372 if (type & IRQ_TYPE_EDGE_FALLING)
373 adnp->irq_fall[reg] |= BIT(pos);
374 else
375 adnp->irq_fall[reg] &= ~BIT(pos);
376
377 if (type & IRQ_TYPE_LEVEL_HIGH)
378 adnp->irq_high[reg] |= BIT(pos);
379 else
380 adnp->irq_high[reg] &= ~BIT(pos);
381
382 if (type & IRQ_TYPE_LEVEL_LOW)
383 adnp->irq_low[reg] |= BIT(pos);
384 else
385 adnp->irq_low[reg] &= ~BIT(pos);
386
387 return 0;
388}
389
390static void adnp_irq_bus_lock(struct irq_data *data)
391{
392 struct adnp *adnp = irq_data_get_irq_chip_data(data);
393
394 mutex_lock(&adnp->irq_lock);
395}
396
397static void adnp_irq_bus_unlock(struct irq_data *data)
398{
399 struct adnp *adnp = irq_data_get_irq_chip_data(data);
400 unsigned int num_regs = 1 << adnp->reg_shift, i;
401
402 mutex_lock(&adnp->i2c_lock);
403
404 for (i = 0; i < num_regs; i++)
405 adnp_write(adnp, GPIO_IER(adnp) + i, adnp->irq_enable[i]);
406
407 mutex_unlock(&adnp->i2c_lock);
408 mutex_unlock(&adnp->irq_lock);
409}
410
411static int adnp_irq_reqres(struct irq_data *data)
412{
413 struct adnp *adnp = irq_data_get_irq_chip_data(data);
414
415 if (gpio_lock_as_irq(&adnp->gpio, data->hwirq)) {
416 dev_err(adnp->gpio.dev,
417 "unable to lock HW IRQ %lu for IRQ\n",
418 data->hwirq);
419 return -EINVAL;
420 }
421 return 0;
422}
423
424static void adnp_irq_relres(struct irq_data *data)
425{
426 struct adnp *adnp = irq_data_get_irq_chip_data(data);
427
428 gpio_unlock_as_irq(&adnp->gpio, data->hwirq);
429}
430
431static struct irq_chip adnp_irq_chip = {
432 .name = "gpio-adnp",
433 .irq_mask = adnp_irq_mask,
434 .irq_unmask = adnp_irq_unmask,
435 .irq_set_type = adnp_irq_set_type,
436 .irq_bus_lock = adnp_irq_bus_lock,
437 .irq_bus_sync_unlock = adnp_irq_bus_unlock,
438 .irq_request_resources = adnp_irq_reqres,
439 .irq_release_resources = adnp_irq_relres,
440};
441
442static int adnp_irq_map(struct irq_domain *domain, unsigned int irq,
443 irq_hw_number_t hwirq)
444{
445 irq_set_chip_data(irq, domain->host_data);
446 irq_set_chip(irq, &adnp_irq_chip);
447 irq_set_nested_thread(irq, true);
448
449#ifdef CONFIG_ARM
450 set_irq_flags(irq, IRQF_VALID);
451#else
452 irq_set_noprobe(irq);
453#endif
454
455 return 0;
456}
457
458static const struct irq_domain_ops adnp_irq_domain_ops = {
459 .map = adnp_irq_map,
460 .xlate = irq_domain_xlate_twocell,
461};
462
463static int adnp_irq_setup(struct adnp *adnp)
464{
465 unsigned int num_regs = 1 << adnp->reg_shift, i;
466 struct gpio_chip *chip = &adnp->gpio;
467 int err;
468
469 mutex_init(&adnp->irq_lock);
470
471 /*
472 * Allocate memory to keep track of the current level and trigger
473 * modes of the interrupts. To avoid multiple allocations, a single
474 * large buffer is allocated and pointers are setup to point at the
475 * corresponding offsets. For consistency, the layout of the buffer
476 * is chosen to match the register layout of the hardware in that
477 * each segment contains the corresponding bits for all interrupts.
478 */
479 adnp->irq_enable = devm_kzalloc(chip->dev, num_regs * 6, GFP_KERNEL);
480 if (!adnp->irq_enable)
481 return -ENOMEM;
482
483 adnp->irq_level = adnp->irq_enable + (num_regs * 1);
484 adnp->irq_rise = adnp->irq_enable + (num_regs * 2);
485 adnp->irq_fall = adnp->irq_enable + (num_regs * 3);
486 adnp->irq_high = adnp->irq_enable + (num_regs * 4);
487 adnp->irq_low = adnp->irq_enable + (num_regs * 5);
488
489 for (i = 0; i < num_regs; i++) {
490 /*
491 * Read the initial level of all pins to allow the emulation
492 * of edge triggered interrupts.
493 */
494 err = adnp_read(adnp, GPIO_PLR(adnp) + i, &adnp->irq_level[i]);
495 if (err < 0)
496 return err;
497
498 /* disable all interrupts */
499 err = adnp_write(adnp, GPIO_IER(adnp) + i, 0);
500 if (err < 0)
501 return err;
502
503 adnp->irq_enable[i] = 0x00;
504 }
505
506 adnp->domain = irq_domain_add_linear(chip->of_node, chip->ngpio,
507 &adnp_irq_domain_ops, adnp);
508
509 err = request_threaded_irq(adnp->client->irq, NULL, adnp_irq,
510 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
511 dev_name(chip->dev), adnp);
512 if (err != 0) {
513 dev_err(chip->dev, "can't request IRQ#%d: %d\n",
514 adnp->client->irq, err);
515 return err;
516 }
517
518 chip->to_irq = adnp_gpio_to_irq;
519 return 0;
520}
521
522static void adnp_irq_teardown(struct adnp *adnp)
523{
524 unsigned int irq, i;
525
526 free_irq(adnp->client->irq, adnp);
527
528 for (i = 0; i < adnp->gpio.ngpio; i++) {
529 irq = irq_find_mapping(adnp->domain, i);
530 if (irq > 0)
531 irq_dispose_mapping(irq);
532 }
533
534 irq_domain_remove(adnp->domain);
535}
536
537static int adnp_i2c_probe(struct i2c_client *client,
538 const struct i2c_device_id *id)
539{
540 struct device_node *np = client->dev.of_node;
541 struct adnp *adnp;
542 u32 num_gpios;
543 int err;
544
545 err = of_property_read_u32(np, "nr-gpios", &num_gpios);
546 if (err < 0)
547 return err;
548
549 client->irq = irq_of_parse_and_map(np, 0);
550 if (!client->irq)
551 return -EPROBE_DEFER;
552
553 adnp = devm_kzalloc(&client->dev, sizeof(*adnp), GFP_KERNEL);
554 if (!adnp)
555 return -ENOMEM;
556
557 mutex_init(&adnp->i2c_lock);
558 adnp->client = client;
559
560 err = adnp_gpio_setup(adnp, num_gpios);
561 if (err < 0)
562 return err;
563
564 if (of_find_property(np, "interrupt-controller", NULL)) {
565 err = adnp_irq_setup(adnp);
566 if (err < 0)
567 goto teardown;
568 }
569
570 err = gpiochip_add(&adnp->gpio);
571 if (err < 0)
572 goto teardown;
573
574 i2c_set_clientdata(client, adnp);
575 return 0;
576
577teardown:
578 if (of_find_property(np, "interrupt-controller", NULL))
579 adnp_irq_teardown(adnp);
580
581 return err;
582}
583
584static int adnp_i2c_remove(struct i2c_client *client)
585{
586 struct adnp *adnp = i2c_get_clientdata(client);
587 struct device_node *np = client->dev.of_node;
588 int err;
589
590 err = gpiochip_remove(&adnp->gpio);
591 if (err < 0) {
592 dev_err(&client->dev, "%s failed: %d\n", "gpiochip_remove()",
593 err);
594 return err;
595 }
596
597 if (of_find_property(np, "interrupt-controller", NULL))
598 adnp_irq_teardown(adnp);
599
600 return 0;
601}
602
603static const struct i2c_device_id adnp_i2c_id[] = {
604 { "gpio-adnp" },
605 { },
606};
607MODULE_DEVICE_TABLE(i2c, adnp_i2c_id);
608
609static const struct of_device_id adnp_of_match[] = {
610 { .compatible = "ad,gpio-adnp", },
611 { },
612};
613MODULE_DEVICE_TABLE(of, adnp_of_match);
614
615static struct i2c_driver adnp_i2c_driver = {
616 .driver = {
617 .name = "gpio-adnp",
618 .owner = THIS_MODULE,
619 .of_match_table = adnp_of_match,
620 },
621 .probe = adnp_i2c_probe,
622 .remove = adnp_i2c_remove,
623 .id_table = adnp_i2c_id,
624};
625module_i2c_driver(adnp_i2c_driver);
626
627MODULE_DESCRIPTION("Avionic Design N-bit GPIO expander");
628MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
629MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2011-2012 Avionic Design GmbH
4 */
5
6#include <linux/gpio/driver.h>
7#include <linux/i2c.h>
8#include <linux/interrupt.h>
9#include <linux/module.h>
10#include <linux/of_irq.h>
11#include <linux/seq_file.h>
12#include <linux/slab.h>
13
14#define GPIO_DDR(gpio) (0x00 << (gpio)->reg_shift)
15#define GPIO_PLR(gpio) (0x01 << (gpio)->reg_shift)
16#define GPIO_IER(gpio) (0x02 << (gpio)->reg_shift)
17#define GPIO_ISR(gpio) (0x03 << (gpio)->reg_shift)
18#define GPIO_PTR(gpio) (0x04 << (gpio)->reg_shift)
19
20struct adnp {
21 struct i2c_client *client;
22 struct gpio_chip gpio;
23 unsigned int reg_shift;
24
25 struct mutex i2c_lock;
26 struct mutex irq_lock;
27
28 u8 *irq_enable;
29 u8 *irq_level;
30 u8 *irq_rise;
31 u8 *irq_fall;
32 u8 *irq_high;
33 u8 *irq_low;
34};
35
36static int adnp_read(struct adnp *adnp, unsigned offset, uint8_t *value)
37{
38 int err;
39
40 err = i2c_smbus_read_byte_data(adnp->client, offset);
41 if (err < 0) {
42 dev_err(adnp->gpio.parent, "%s failed: %d\n",
43 "i2c_smbus_read_byte_data()", err);
44 return err;
45 }
46
47 *value = err;
48 return 0;
49}
50
51static int adnp_write(struct adnp *adnp, unsigned offset, uint8_t value)
52{
53 int err;
54
55 err = i2c_smbus_write_byte_data(adnp->client, offset, value);
56 if (err < 0) {
57 dev_err(adnp->gpio.parent, "%s failed: %d\n",
58 "i2c_smbus_write_byte_data()", err);
59 return err;
60 }
61
62 return 0;
63}
64
65static int adnp_gpio_get(struct gpio_chip *chip, unsigned offset)
66{
67 struct adnp *adnp = gpiochip_get_data(chip);
68 unsigned int reg = offset >> adnp->reg_shift;
69 unsigned int pos = offset & 7;
70 u8 value;
71 int err;
72
73 err = adnp_read(adnp, GPIO_PLR(adnp) + reg, &value);
74 if (err < 0)
75 return err;
76
77 return (value & BIT(pos)) ? 1 : 0;
78}
79
80static void __adnp_gpio_set(struct adnp *adnp, unsigned offset, int value)
81{
82 unsigned int reg = offset >> adnp->reg_shift;
83 unsigned int pos = offset & 7;
84 int err;
85 u8 val;
86
87 err = adnp_read(adnp, GPIO_PLR(adnp) + reg, &val);
88 if (err < 0)
89 return;
90
91 if (value)
92 val |= BIT(pos);
93 else
94 val &= ~BIT(pos);
95
96 adnp_write(adnp, GPIO_PLR(adnp) + reg, val);
97}
98
99static void adnp_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
100{
101 struct adnp *adnp = gpiochip_get_data(chip);
102
103 mutex_lock(&adnp->i2c_lock);
104 __adnp_gpio_set(adnp, offset, value);
105 mutex_unlock(&adnp->i2c_lock);
106}
107
108static int adnp_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
109{
110 struct adnp *adnp = gpiochip_get_data(chip);
111 unsigned int reg = offset >> adnp->reg_shift;
112 unsigned int pos = offset & 7;
113 u8 value;
114 int err;
115
116 mutex_lock(&adnp->i2c_lock);
117
118 err = adnp_read(adnp, GPIO_DDR(adnp) + reg, &value);
119 if (err < 0)
120 goto out;
121
122 value &= ~BIT(pos);
123
124 err = adnp_write(adnp, GPIO_DDR(adnp) + reg, value);
125 if (err < 0)
126 goto out;
127
128 err = adnp_read(adnp, GPIO_DDR(adnp) + reg, &value);
129 if (err < 0)
130 goto out;
131
132 if (value & BIT(pos)) {
133 err = -EPERM;
134 goto out;
135 }
136
137 err = 0;
138
139out:
140 mutex_unlock(&adnp->i2c_lock);
141 return err;
142}
143
144static int adnp_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
145 int value)
146{
147 struct adnp *adnp = gpiochip_get_data(chip);
148 unsigned int reg = offset >> adnp->reg_shift;
149 unsigned int pos = offset & 7;
150 int err;
151 u8 val;
152
153 mutex_lock(&adnp->i2c_lock);
154
155 err = adnp_read(adnp, GPIO_DDR(adnp) + reg, &val);
156 if (err < 0)
157 goto out;
158
159 val |= BIT(pos);
160
161 err = adnp_write(adnp, GPIO_DDR(adnp) + reg, val);
162 if (err < 0)
163 goto out;
164
165 err = adnp_read(adnp, GPIO_DDR(adnp) + reg, &val);
166 if (err < 0)
167 goto out;
168
169 if (!(val & BIT(pos))) {
170 err = -EPERM;
171 goto out;
172 }
173
174 __adnp_gpio_set(adnp, offset, value);
175 err = 0;
176
177out:
178 mutex_unlock(&adnp->i2c_lock);
179 return err;
180}
181
182static void adnp_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
183{
184 struct adnp *adnp = gpiochip_get_data(chip);
185 unsigned int num_regs = 1 << adnp->reg_shift, i, j;
186 int err;
187
188 for (i = 0; i < num_regs; i++) {
189 u8 ddr, plr, ier, isr;
190
191 mutex_lock(&adnp->i2c_lock);
192
193 err = adnp_read(adnp, GPIO_DDR(adnp) + i, &ddr);
194 if (err < 0)
195 goto unlock;
196
197 err = adnp_read(adnp, GPIO_PLR(adnp) + i, &plr);
198 if (err < 0)
199 goto unlock;
200
201 err = adnp_read(adnp, GPIO_IER(adnp) + i, &ier);
202 if (err < 0)
203 goto unlock;
204
205 err = adnp_read(adnp, GPIO_ISR(adnp) + i, &isr);
206 if (err < 0)
207 goto unlock;
208
209 mutex_unlock(&adnp->i2c_lock);
210
211 for (j = 0; j < 8; j++) {
212 unsigned int bit = (i << adnp->reg_shift) + j;
213 const char *direction = "input ";
214 const char *level = "low ";
215 const char *interrupt = "disabled";
216 const char *pending = "";
217
218 if (ddr & BIT(j))
219 direction = "output";
220
221 if (plr & BIT(j))
222 level = "high";
223
224 if (ier & BIT(j))
225 interrupt = "enabled ";
226
227 if (isr & BIT(j))
228 pending = "pending";
229
230 seq_printf(s, "%2u: %s %s IRQ %s %s\n", bit,
231 direction, level, interrupt, pending);
232 }
233 }
234
235 return;
236
237unlock:
238 mutex_unlock(&adnp->i2c_lock);
239}
240
241static int adnp_gpio_setup(struct adnp *adnp, unsigned int num_gpios)
242{
243 struct gpio_chip *chip = &adnp->gpio;
244 int err;
245
246 adnp->reg_shift = get_count_order(num_gpios) - 3;
247
248 chip->direction_input = adnp_gpio_direction_input;
249 chip->direction_output = adnp_gpio_direction_output;
250 chip->get = adnp_gpio_get;
251 chip->set = adnp_gpio_set;
252 chip->can_sleep = true;
253
254 if (IS_ENABLED(CONFIG_DEBUG_FS))
255 chip->dbg_show = adnp_gpio_dbg_show;
256
257 chip->base = -1;
258 chip->ngpio = num_gpios;
259 chip->label = adnp->client->name;
260 chip->parent = &adnp->client->dev;
261 chip->of_node = chip->parent->of_node;
262 chip->owner = THIS_MODULE;
263
264 err = devm_gpiochip_add_data(&adnp->client->dev, chip, adnp);
265 if (err)
266 return err;
267
268 return 0;
269}
270
271static irqreturn_t adnp_irq(int irq, void *data)
272{
273 struct adnp *adnp = data;
274 unsigned int num_regs, i;
275
276 num_regs = 1 << adnp->reg_shift;
277
278 for (i = 0; i < num_regs; i++) {
279 unsigned int base = i << adnp->reg_shift, bit;
280 u8 changed, level, isr, ier;
281 unsigned long pending;
282 int err;
283
284 mutex_lock(&adnp->i2c_lock);
285
286 err = adnp_read(adnp, GPIO_PLR(adnp) + i, &level);
287 if (err < 0) {
288 mutex_unlock(&adnp->i2c_lock);
289 continue;
290 }
291
292 err = adnp_read(adnp, GPIO_ISR(adnp) + i, &isr);
293 if (err < 0) {
294 mutex_unlock(&adnp->i2c_lock);
295 continue;
296 }
297
298 err = adnp_read(adnp, GPIO_IER(adnp) + i, &ier);
299 if (err < 0) {
300 mutex_unlock(&adnp->i2c_lock);
301 continue;
302 }
303
304 mutex_unlock(&adnp->i2c_lock);
305
306 /* determine pins that changed levels */
307 changed = level ^ adnp->irq_level[i];
308
309 /* compute edge-triggered interrupts */
310 pending = changed & ((adnp->irq_fall[i] & ~level) |
311 (adnp->irq_rise[i] & level));
312
313 /* add in level-triggered interrupts */
314 pending |= (adnp->irq_high[i] & level) |
315 (adnp->irq_low[i] & ~level);
316
317 /* mask out non-pending and disabled interrupts */
318 pending &= isr & ier;
319
320 for_each_set_bit(bit, &pending, 8) {
321 unsigned int child_irq;
322 child_irq = irq_find_mapping(adnp->gpio.irq.domain,
323 base + bit);
324 handle_nested_irq(child_irq);
325 }
326 }
327
328 return IRQ_HANDLED;
329}
330
331static void adnp_irq_mask(struct irq_data *d)
332{
333 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
334 struct adnp *adnp = gpiochip_get_data(gc);
335 unsigned int reg = d->hwirq >> adnp->reg_shift;
336 unsigned int pos = d->hwirq & 7;
337
338 adnp->irq_enable[reg] &= ~BIT(pos);
339}
340
341static void adnp_irq_unmask(struct irq_data *d)
342{
343 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
344 struct adnp *adnp = gpiochip_get_data(gc);
345 unsigned int reg = d->hwirq >> adnp->reg_shift;
346 unsigned int pos = d->hwirq & 7;
347
348 adnp->irq_enable[reg] |= BIT(pos);
349}
350
351static int adnp_irq_set_type(struct irq_data *d, unsigned int type)
352{
353 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
354 struct adnp *adnp = gpiochip_get_data(gc);
355 unsigned int reg = d->hwirq >> adnp->reg_shift;
356 unsigned int pos = d->hwirq & 7;
357
358 if (type & IRQ_TYPE_EDGE_RISING)
359 adnp->irq_rise[reg] |= BIT(pos);
360 else
361 adnp->irq_rise[reg] &= ~BIT(pos);
362
363 if (type & IRQ_TYPE_EDGE_FALLING)
364 adnp->irq_fall[reg] |= BIT(pos);
365 else
366 adnp->irq_fall[reg] &= ~BIT(pos);
367
368 if (type & IRQ_TYPE_LEVEL_HIGH)
369 adnp->irq_high[reg] |= BIT(pos);
370 else
371 adnp->irq_high[reg] &= ~BIT(pos);
372
373 if (type & IRQ_TYPE_LEVEL_LOW)
374 adnp->irq_low[reg] |= BIT(pos);
375 else
376 adnp->irq_low[reg] &= ~BIT(pos);
377
378 return 0;
379}
380
381static void adnp_irq_bus_lock(struct irq_data *d)
382{
383 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
384 struct adnp *adnp = gpiochip_get_data(gc);
385
386 mutex_lock(&adnp->irq_lock);
387}
388
389static void adnp_irq_bus_unlock(struct irq_data *d)
390{
391 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
392 struct adnp *adnp = gpiochip_get_data(gc);
393 unsigned int num_regs = 1 << adnp->reg_shift, i;
394
395 mutex_lock(&adnp->i2c_lock);
396
397 for (i = 0; i < num_regs; i++)
398 adnp_write(adnp, GPIO_IER(adnp) + i, adnp->irq_enable[i]);
399
400 mutex_unlock(&adnp->i2c_lock);
401 mutex_unlock(&adnp->irq_lock);
402}
403
404static struct irq_chip adnp_irq_chip = {
405 .name = "gpio-adnp",
406 .irq_mask = adnp_irq_mask,
407 .irq_unmask = adnp_irq_unmask,
408 .irq_set_type = adnp_irq_set_type,
409 .irq_bus_lock = adnp_irq_bus_lock,
410 .irq_bus_sync_unlock = adnp_irq_bus_unlock,
411};
412
413static int adnp_irq_setup(struct adnp *adnp)
414{
415 unsigned int num_regs = 1 << adnp->reg_shift, i;
416 struct gpio_chip *chip = &adnp->gpio;
417 int err;
418
419 mutex_init(&adnp->irq_lock);
420
421 /*
422 * Allocate memory to keep track of the current level and trigger
423 * modes of the interrupts. To avoid multiple allocations, a single
424 * large buffer is allocated and pointers are setup to point at the
425 * corresponding offsets. For consistency, the layout of the buffer
426 * is chosen to match the register layout of the hardware in that
427 * each segment contains the corresponding bits for all interrupts.
428 */
429 adnp->irq_enable = devm_kcalloc(chip->parent, num_regs, 6,
430 GFP_KERNEL);
431 if (!adnp->irq_enable)
432 return -ENOMEM;
433
434 adnp->irq_level = adnp->irq_enable + (num_regs * 1);
435 adnp->irq_rise = adnp->irq_enable + (num_regs * 2);
436 adnp->irq_fall = adnp->irq_enable + (num_regs * 3);
437 adnp->irq_high = adnp->irq_enable + (num_regs * 4);
438 adnp->irq_low = adnp->irq_enable + (num_regs * 5);
439
440 for (i = 0; i < num_regs; i++) {
441 /*
442 * Read the initial level of all pins to allow the emulation
443 * of edge triggered interrupts.
444 */
445 err = adnp_read(adnp, GPIO_PLR(adnp) + i, &adnp->irq_level[i]);
446 if (err < 0)
447 return err;
448
449 /* disable all interrupts */
450 err = adnp_write(adnp, GPIO_IER(adnp) + i, 0);
451 if (err < 0)
452 return err;
453
454 adnp->irq_enable[i] = 0x00;
455 }
456
457 err = devm_request_threaded_irq(chip->parent, adnp->client->irq,
458 NULL, adnp_irq,
459 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
460 dev_name(chip->parent), adnp);
461 if (err != 0) {
462 dev_err(chip->parent, "can't request IRQ#%d: %d\n",
463 adnp->client->irq, err);
464 return err;
465 }
466
467 err = gpiochip_irqchip_add_nested(chip,
468 &adnp_irq_chip,
469 0,
470 handle_simple_irq,
471 IRQ_TYPE_NONE);
472 if (err) {
473 dev_err(chip->parent,
474 "could not connect irqchip to gpiochip\n");
475 return err;
476 }
477
478 gpiochip_set_nested_irqchip(chip, &adnp_irq_chip, adnp->client->irq);
479
480 return 0;
481}
482
483static int adnp_i2c_probe(struct i2c_client *client,
484 const struct i2c_device_id *id)
485{
486 struct device_node *np = client->dev.of_node;
487 struct adnp *adnp;
488 u32 num_gpios;
489 int err;
490
491 err = of_property_read_u32(np, "nr-gpios", &num_gpios);
492 if (err < 0)
493 return err;
494
495 client->irq = irq_of_parse_and_map(np, 0);
496 if (!client->irq)
497 return -EPROBE_DEFER;
498
499 adnp = devm_kzalloc(&client->dev, sizeof(*adnp), GFP_KERNEL);
500 if (!adnp)
501 return -ENOMEM;
502
503 mutex_init(&adnp->i2c_lock);
504 adnp->client = client;
505
506 err = adnp_gpio_setup(adnp, num_gpios);
507 if (err)
508 return err;
509
510 if (of_find_property(np, "interrupt-controller", NULL)) {
511 err = adnp_irq_setup(adnp);
512 if (err)
513 return err;
514 }
515
516 i2c_set_clientdata(client, adnp);
517
518 return 0;
519}
520
521static const struct i2c_device_id adnp_i2c_id[] = {
522 { "gpio-adnp" },
523 { },
524};
525MODULE_DEVICE_TABLE(i2c, adnp_i2c_id);
526
527static const struct of_device_id adnp_of_match[] = {
528 { .compatible = "ad,gpio-adnp", },
529 { },
530};
531MODULE_DEVICE_TABLE(of, adnp_of_match);
532
533static struct i2c_driver adnp_i2c_driver = {
534 .driver = {
535 .name = "gpio-adnp",
536 .of_match_table = adnp_of_match,
537 },
538 .probe = adnp_i2c_probe,
539 .id_table = adnp_i2c_id,
540};
541module_i2c_driver(adnp_i2c_driver);
542
543MODULE_DESCRIPTION("Avionic Design N-bit GPIO expander");
544MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
545MODULE_LICENSE("GPL");