This source file includes following definitions.
- max732x_writeb
- max732x_readb
- is_group_a
- max732x_gpio_get_value
- max732x_gpio_set_mask
- max732x_gpio_set_value
- max732x_gpio_set_multiple
- max732x_gpio_direction_input
- max732x_gpio_direction_output
- max732x_writew
- max732x_readw
- max732x_irq_update_mask
- max732x_irq_mask
- max732x_irq_unmask
- max732x_irq_bus_lock
- max732x_irq_bus_sync_unlock
- max732x_irq_set_type
- max732x_irq_set_wake
- max732x_irq_pending
- max732x_irq_handler
- max732x_irq_setup
- max732x_irq_setup
- max732x_setup_gpio
- of_gpio_max732x
- max732x_probe
- max732x_remove
- max732x_init
- max732x_exit
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13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/slab.h>
16 #include <linux/string.h>
17 #include <linux/gpio/driver.h>
18 #include <linux/interrupt.h>
19 #include <linux/i2c.h>
20 #include <linux/platform_data/max732x.h>
21 #include <linux/of.h>
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57
58 #define PORT_NONE 0x0
59 #define PORT_OUTPUT 0x1
60 #define PORT_INPUT 0x2
61 #define PORT_OPENDRAIN 0x3
62
63 #define IO_4I4O 0x5AA5
64 #define IO_4P4O 0x5FF5
65 #define IO_8I 0xAAAA
66 #define IO_8P 0xFFFF
67 #define IO_8O 0x5555
68
69 #define GROUP_A(x) ((x) & 0xffff)
70 #define GROUP_B(x) ((x) << 16)
71
72 #define INT_NONE 0x0
73 #define INT_NO_MASK 0x1
74 #define INT_INDEP_MASK 0x2
75 #define INT_MERGED_MASK 0x3
76
77 #define INT_CAPS(x) (((uint64_t)(x)) << 32)
78
79 enum {
80 MAX7319,
81 MAX7320,
82 MAX7321,
83 MAX7322,
84 MAX7323,
85 MAX7324,
86 MAX7325,
87 MAX7326,
88 MAX7327,
89 };
90
91 static uint64_t max732x_features[] = {
92 [MAX7319] = GROUP_A(IO_8I) | INT_CAPS(INT_MERGED_MASK),
93 [MAX7320] = GROUP_B(IO_8O),
94 [MAX7321] = GROUP_A(IO_8P) | INT_CAPS(INT_NO_MASK),
95 [MAX7322] = GROUP_A(IO_4I4O) | INT_CAPS(INT_MERGED_MASK),
96 [MAX7323] = GROUP_A(IO_4P4O) | INT_CAPS(INT_INDEP_MASK),
97 [MAX7324] = GROUP_A(IO_8I) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK),
98 [MAX7325] = GROUP_A(IO_8P) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK),
99 [MAX7326] = GROUP_A(IO_4I4O) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK),
100 [MAX7327] = GROUP_A(IO_4P4O) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK),
101 };
102
103 static const struct i2c_device_id max732x_id[] = {
104 { "max7319", MAX7319 },
105 { "max7320", MAX7320 },
106 { "max7321", MAX7321 },
107 { "max7322", MAX7322 },
108 { "max7323", MAX7323 },
109 { "max7324", MAX7324 },
110 { "max7325", MAX7325 },
111 { "max7326", MAX7326 },
112 { "max7327", MAX7327 },
113 { },
114 };
115 MODULE_DEVICE_TABLE(i2c, max732x_id);
116
117 #ifdef CONFIG_OF
118 static const struct of_device_id max732x_of_table[] = {
119 { .compatible = "maxim,max7319" },
120 { .compatible = "maxim,max7320" },
121 { .compatible = "maxim,max7321" },
122 { .compatible = "maxim,max7322" },
123 { .compatible = "maxim,max7323" },
124 { .compatible = "maxim,max7324" },
125 { .compatible = "maxim,max7325" },
126 { .compatible = "maxim,max7326" },
127 { .compatible = "maxim,max7327" },
128 { }
129 };
130 MODULE_DEVICE_TABLE(of, max732x_of_table);
131 #endif
132
133 struct max732x_chip {
134 struct gpio_chip gpio_chip;
135
136 struct i2c_client *client;
137 struct i2c_client *client_dummy;
138 struct i2c_client *client_group_a;
139 struct i2c_client *client_group_b;
140
141 unsigned int mask_group_a;
142 unsigned int dir_input;
143 unsigned int dir_output;
144
145 struct mutex lock;
146 uint8_t reg_out[2];
147
148 #ifdef CONFIG_GPIO_MAX732X_IRQ
149 struct mutex irq_lock;
150 uint8_t irq_mask;
151 uint8_t irq_mask_cur;
152 uint8_t irq_trig_raise;
153 uint8_t irq_trig_fall;
154 uint8_t irq_features;
155 #endif
156 };
157
158 static int max732x_writeb(struct max732x_chip *chip, int group_a, uint8_t val)
159 {
160 struct i2c_client *client;
161 int ret;
162
163 client = group_a ? chip->client_group_a : chip->client_group_b;
164 ret = i2c_smbus_write_byte(client, val);
165 if (ret < 0) {
166 dev_err(&client->dev, "failed writing\n");
167 return ret;
168 }
169
170 return 0;
171 }
172
173 static int max732x_readb(struct max732x_chip *chip, int group_a, uint8_t *val)
174 {
175 struct i2c_client *client;
176 int ret;
177
178 client = group_a ? chip->client_group_a : chip->client_group_b;
179 ret = i2c_smbus_read_byte(client);
180 if (ret < 0) {
181 dev_err(&client->dev, "failed reading\n");
182 return ret;
183 }
184
185 *val = (uint8_t)ret;
186 return 0;
187 }
188
189 static inline int is_group_a(struct max732x_chip *chip, unsigned off)
190 {
191 return (1u << off) & chip->mask_group_a;
192 }
193
194 static int max732x_gpio_get_value(struct gpio_chip *gc, unsigned off)
195 {
196 struct max732x_chip *chip = gpiochip_get_data(gc);
197 uint8_t reg_val;
198 int ret;
199
200 ret = max732x_readb(chip, is_group_a(chip, off), ®_val);
201 if (ret < 0)
202 return ret;
203
204 return !!(reg_val & (1u << (off & 0x7)));
205 }
206
207 static void max732x_gpio_set_mask(struct gpio_chip *gc, unsigned off, int mask,
208 int val)
209 {
210 struct max732x_chip *chip = gpiochip_get_data(gc);
211 uint8_t reg_out;
212 int ret;
213
214 mutex_lock(&chip->lock);
215
216 reg_out = (off > 7) ? chip->reg_out[1] : chip->reg_out[0];
217 reg_out = (reg_out & ~mask) | (val & mask);
218
219 ret = max732x_writeb(chip, is_group_a(chip, off), reg_out);
220 if (ret < 0)
221 goto out;
222
223
224 if (off > 7)
225 chip->reg_out[1] = reg_out;
226 else
227 chip->reg_out[0] = reg_out;
228 out:
229 mutex_unlock(&chip->lock);
230 }
231
232 static void max732x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
233 {
234 unsigned base = off & ~0x7;
235 uint8_t mask = 1u << (off & 0x7);
236
237 max732x_gpio_set_mask(gc, base, mask, val << (off & 0x7));
238 }
239
240 static void max732x_gpio_set_multiple(struct gpio_chip *gc,
241 unsigned long *mask, unsigned long *bits)
242 {
243 unsigned mask_lo = mask[0] & 0xff;
244 unsigned mask_hi = (mask[0] >> 8) & 0xff;
245
246 if (mask_lo)
247 max732x_gpio_set_mask(gc, 0, mask_lo, bits[0] & 0xff);
248 if (mask_hi)
249 max732x_gpio_set_mask(gc, 8, mask_hi, (bits[0] >> 8) & 0xff);
250 }
251
252 static int max732x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
253 {
254 struct max732x_chip *chip = gpiochip_get_data(gc);
255 unsigned int mask = 1u << off;
256
257 if ((mask & chip->dir_input) == 0) {
258 dev_dbg(&chip->client->dev, "%s port %d is output only\n",
259 chip->client->name, off);
260 return -EACCES;
261 }
262
263
264
265
266
267 if ((mask & chip->dir_output))
268 max732x_gpio_set_value(gc, off, 1);
269
270 return 0;
271 }
272
273 static int max732x_gpio_direction_output(struct gpio_chip *gc,
274 unsigned off, int val)
275 {
276 struct max732x_chip *chip = gpiochip_get_data(gc);
277 unsigned int mask = 1u << off;
278
279 if ((mask & chip->dir_output) == 0) {
280 dev_dbg(&chip->client->dev, "%s port %d is input only\n",
281 chip->client->name, off);
282 return -EACCES;
283 }
284
285 max732x_gpio_set_value(gc, off, val);
286 return 0;
287 }
288
289 #ifdef CONFIG_GPIO_MAX732X_IRQ
290 static int max732x_writew(struct max732x_chip *chip, uint16_t val)
291 {
292 int ret;
293
294 val = cpu_to_le16(val);
295
296 ret = i2c_master_send(chip->client_group_a, (char *)&val, 2);
297 if (ret < 0) {
298 dev_err(&chip->client_group_a->dev, "failed writing\n");
299 return ret;
300 }
301
302 return 0;
303 }
304
305 static int max732x_readw(struct max732x_chip *chip, uint16_t *val)
306 {
307 int ret;
308
309 ret = i2c_master_recv(chip->client_group_a, (char *)val, 2);
310 if (ret < 0) {
311 dev_err(&chip->client_group_a->dev, "failed reading\n");
312 return ret;
313 }
314
315 *val = le16_to_cpu(*val);
316 return 0;
317 }
318
319 static void max732x_irq_update_mask(struct max732x_chip *chip)
320 {
321 uint16_t msg;
322
323 if (chip->irq_mask == chip->irq_mask_cur)
324 return;
325
326 chip->irq_mask = chip->irq_mask_cur;
327
328 if (chip->irq_features == INT_NO_MASK)
329 return;
330
331 mutex_lock(&chip->lock);
332
333 switch (chip->irq_features) {
334 case INT_INDEP_MASK:
335 msg = (chip->irq_mask << 8) | chip->reg_out[0];
336 max732x_writew(chip, msg);
337 break;
338
339 case INT_MERGED_MASK:
340 msg = chip->irq_mask | chip->reg_out[0];
341 max732x_writeb(chip, 1, (uint8_t)msg);
342 break;
343 }
344
345 mutex_unlock(&chip->lock);
346 }
347
348 static void max732x_irq_mask(struct irq_data *d)
349 {
350 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
351 struct max732x_chip *chip = gpiochip_get_data(gc);
352
353 chip->irq_mask_cur &= ~(1 << d->hwirq);
354 }
355
356 static void max732x_irq_unmask(struct irq_data *d)
357 {
358 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
359 struct max732x_chip *chip = gpiochip_get_data(gc);
360
361 chip->irq_mask_cur |= 1 << d->hwirq;
362 }
363
364 static void max732x_irq_bus_lock(struct irq_data *d)
365 {
366 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
367 struct max732x_chip *chip = gpiochip_get_data(gc);
368
369 mutex_lock(&chip->irq_lock);
370 chip->irq_mask_cur = chip->irq_mask;
371 }
372
373 static void max732x_irq_bus_sync_unlock(struct irq_data *d)
374 {
375 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
376 struct max732x_chip *chip = gpiochip_get_data(gc);
377 uint16_t new_irqs;
378 uint16_t level;
379
380 max732x_irq_update_mask(chip);
381
382 new_irqs = chip->irq_trig_fall | chip->irq_trig_raise;
383 while (new_irqs) {
384 level = __ffs(new_irqs);
385 max732x_gpio_direction_input(&chip->gpio_chip, level);
386 new_irqs &= ~(1 << level);
387 }
388
389 mutex_unlock(&chip->irq_lock);
390 }
391
392 static int max732x_irq_set_type(struct irq_data *d, unsigned int type)
393 {
394 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
395 struct max732x_chip *chip = gpiochip_get_data(gc);
396 uint16_t off = d->hwirq;
397 uint16_t mask = 1 << off;
398
399 if (!(mask & chip->dir_input)) {
400 dev_dbg(&chip->client->dev, "%s port %d is output only\n",
401 chip->client->name, off);
402 return -EACCES;
403 }
404
405 if (!(type & IRQ_TYPE_EDGE_BOTH)) {
406 dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
407 d->irq, type);
408 return -EINVAL;
409 }
410
411 if (type & IRQ_TYPE_EDGE_FALLING)
412 chip->irq_trig_fall |= mask;
413 else
414 chip->irq_trig_fall &= ~mask;
415
416 if (type & IRQ_TYPE_EDGE_RISING)
417 chip->irq_trig_raise |= mask;
418 else
419 chip->irq_trig_raise &= ~mask;
420
421 return 0;
422 }
423
424 static int max732x_irq_set_wake(struct irq_data *data, unsigned int on)
425 {
426 struct max732x_chip *chip = irq_data_get_irq_chip_data(data);
427
428 irq_set_irq_wake(chip->client->irq, on);
429 return 0;
430 }
431
432 static struct irq_chip max732x_irq_chip = {
433 .name = "max732x",
434 .irq_mask = max732x_irq_mask,
435 .irq_unmask = max732x_irq_unmask,
436 .irq_bus_lock = max732x_irq_bus_lock,
437 .irq_bus_sync_unlock = max732x_irq_bus_sync_unlock,
438 .irq_set_type = max732x_irq_set_type,
439 .irq_set_wake = max732x_irq_set_wake,
440 };
441
442 static uint8_t max732x_irq_pending(struct max732x_chip *chip)
443 {
444 uint8_t cur_stat;
445 uint8_t old_stat;
446 uint8_t trigger;
447 uint8_t pending;
448 uint16_t status;
449 int ret;
450
451 ret = max732x_readw(chip, &status);
452 if (ret)
453 return 0;
454
455 trigger = status >> 8;
456 trigger &= chip->irq_mask;
457
458 if (!trigger)
459 return 0;
460
461 cur_stat = status & 0xFF;
462 cur_stat &= chip->irq_mask;
463
464 old_stat = cur_stat ^ trigger;
465
466 pending = (old_stat & chip->irq_trig_fall) |
467 (cur_stat & chip->irq_trig_raise);
468 pending &= trigger;
469
470 return pending;
471 }
472
473 static irqreturn_t max732x_irq_handler(int irq, void *devid)
474 {
475 struct max732x_chip *chip = devid;
476 uint8_t pending;
477 uint8_t level;
478
479 pending = max732x_irq_pending(chip);
480
481 if (!pending)
482 return IRQ_HANDLED;
483
484 do {
485 level = __ffs(pending);
486 handle_nested_irq(irq_find_mapping(chip->gpio_chip.irq.domain,
487 level));
488
489 pending &= ~(1 << level);
490 } while (pending);
491
492 return IRQ_HANDLED;
493 }
494
495 static int max732x_irq_setup(struct max732x_chip *chip,
496 const struct i2c_device_id *id)
497 {
498 struct i2c_client *client = chip->client;
499 struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
500 int has_irq = max732x_features[id->driver_data] >> 32;
501 int irq_base = 0;
502 int ret;
503
504 if (((pdata && pdata->irq_base) || client->irq)
505 && has_irq != INT_NONE) {
506 if (pdata)
507 irq_base = pdata->irq_base;
508 chip->irq_features = has_irq;
509 mutex_init(&chip->irq_lock);
510
511 ret = devm_request_threaded_irq(&client->dev, client->irq,
512 NULL, max732x_irq_handler, IRQF_ONESHOT |
513 IRQF_TRIGGER_FALLING | IRQF_SHARED,
514 dev_name(&client->dev), chip);
515 if (ret) {
516 dev_err(&client->dev, "failed to request irq %d\n",
517 client->irq);
518 return ret;
519 }
520 ret = gpiochip_irqchip_add_nested(&chip->gpio_chip,
521 &max732x_irq_chip,
522 irq_base,
523 handle_simple_irq,
524 IRQ_TYPE_NONE);
525 if (ret) {
526 dev_err(&client->dev,
527 "could not connect irqchip to gpiochip\n");
528 return ret;
529 }
530 gpiochip_set_nested_irqchip(&chip->gpio_chip,
531 &max732x_irq_chip,
532 client->irq);
533 }
534
535 return 0;
536 }
537
538 #else
539 static int max732x_irq_setup(struct max732x_chip *chip,
540 const struct i2c_device_id *id)
541 {
542 struct i2c_client *client = chip->client;
543 struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
544 int has_irq = max732x_features[id->driver_data] >> 32;
545
546 if (((pdata && pdata->irq_base) || client->irq) && has_irq != INT_NONE)
547 dev_warn(&client->dev, "interrupt support not compiled in\n");
548
549 return 0;
550 }
551 #endif
552
553 static int max732x_setup_gpio(struct max732x_chip *chip,
554 const struct i2c_device_id *id,
555 unsigned gpio_start)
556 {
557 struct gpio_chip *gc = &chip->gpio_chip;
558 uint32_t id_data = (uint32_t)max732x_features[id->driver_data];
559 int i, port = 0;
560
561 for (i = 0; i < 16; i++, id_data >>= 2) {
562 unsigned int mask = 1 << port;
563
564 switch (id_data & 0x3) {
565 case PORT_OUTPUT:
566 chip->dir_output |= mask;
567 break;
568 case PORT_INPUT:
569 chip->dir_input |= mask;
570 break;
571 case PORT_OPENDRAIN:
572 chip->dir_output |= mask;
573 chip->dir_input |= mask;
574 break;
575 default:
576 continue;
577 }
578
579 if (i < 8)
580 chip->mask_group_a |= mask;
581 port++;
582 }
583
584 if (chip->dir_input)
585 gc->direction_input = max732x_gpio_direction_input;
586 if (chip->dir_output) {
587 gc->direction_output = max732x_gpio_direction_output;
588 gc->set = max732x_gpio_set_value;
589 gc->set_multiple = max732x_gpio_set_multiple;
590 }
591 gc->get = max732x_gpio_get_value;
592 gc->can_sleep = true;
593
594 gc->base = gpio_start;
595 gc->ngpio = port;
596 gc->label = chip->client->name;
597 gc->parent = &chip->client->dev;
598 gc->owner = THIS_MODULE;
599
600 return port;
601 }
602
603 static struct max732x_platform_data *of_gpio_max732x(struct device *dev)
604 {
605 struct max732x_platform_data *pdata;
606
607 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
608 if (!pdata)
609 return NULL;
610
611 pdata->gpio_base = -1;
612
613 return pdata;
614 }
615
616 static int max732x_probe(struct i2c_client *client,
617 const struct i2c_device_id *id)
618 {
619 struct max732x_platform_data *pdata;
620 struct device_node *node;
621 struct max732x_chip *chip;
622 struct i2c_client *c;
623 uint16_t addr_a, addr_b;
624 int ret, nr_port;
625
626 pdata = dev_get_platdata(&client->dev);
627 node = client->dev.of_node;
628
629 if (!pdata && node)
630 pdata = of_gpio_max732x(&client->dev);
631
632 if (!pdata) {
633 dev_dbg(&client->dev, "no platform data\n");
634 return -EINVAL;
635 }
636
637 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
638 if (chip == NULL)
639 return -ENOMEM;
640 chip->client = client;
641
642 nr_port = max732x_setup_gpio(chip, id, pdata->gpio_base);
643 chip->gpio_chip.parent = &client->dev;
644
645 addr_a = (client->addr & 0x0f) | 0x60;
646 addr_b = (client->addr & 0x0f) | 0x50;
647
648 switch (client->addr & 0x70) {
649 case 0x60:
650 chip->client_group_a = client;
651 if (nr_port > 8) {
652 c = devm_i2c_new_dummy_device(&client->dev,
653 client->adapter, addr_b);
654 if (IS_ERR(c)) {
655 dev_err(&client->dev,
656 "Failed to allocate I2C device\n");
657 return PTR_ERR(c);
658 }
659 chip->client_group_b = chip->client_dummy = c;
660 }
661 break;
662 case 0x50:
663 chip->client_group_b = client;
664 if (nr_port > 8) {
665 c = devm_i2c_new_dummy_device(&client->dev,
666 client->adapter, addr_a);
667 if (IS_ERR(c)) {
668 dev_err(&client->dev,
669 "Failed to allocate I2C device\n");
670 return PTR_ERR(c);
671 }
672 chip->client_group_a = chip->client_dummy = c;
673 }
674 break;
675 default:
676 dev_err(&client->dev, "invalid I2C address specified %02x\n",
677 client->addr);
678 return -EINVAL;
679 }
680
681 if (nr_port > 8 && !chip->client_dummy) {
682 dev_err(&client->dev,
683 "Failed to allocate second group I2C device\n");
684 return -ENODEV;
685 }
686
687 mutex_init(&chip->lock);
688
689 ret = max732x_readb(chip, is_group_a(chip, 0), &chip->reg_out[0]);
690 if (ret)
691 return ret;
692 if (nr_port > 8) {
693 ret = max732x_readb(chip, is_group_a(chip, 8), &chip->reg_out[1]);
694 if (ret)
695 return ret;
696 }
697
698 ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
699 if (ret)
700 return ret;
701
702 ret = max732x_irq_setup(chip, id);
703 if (ret)
704 return ret;
705
706 if (pdata && pdata->setup) {
707 ret = pdata->setup(client, chip->gpio_chip.base,
708 chip->gpio_chip.ngpio, pdata->context);
709 if (ret < 0)
710 dev_warn(&client->dev, "setup failed, %d\n", ret);
711 }
712
713 i2c_set_clientdata(client, chip);
714 return 0;
715 }
716
717 static int max732x_remove(struct i2c_client *client)
718 {
719 struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
720 struct max732x_chip *chip = i2c_get_clientdata(client);
721
722 if (pdata && pdata->teardown) {
723 int ret;
724
725 ret = pdata->teardown(client, chip->gpio_chip.base,
726 chip->gpio_chip.ngpio, pdata->context);
727 if (ret < 0) {
728 dev_err(&client->dev, "%s failed, %d\n",
729 "teardown", ret);
730 return ret;
731 }
732 }
733
734 return 0;
735 }
736
737 static struct i2c_driver max732x_driver = {
738 .driver = {
739 .name = "max732x",
740 .of_match_table = of_match_ptr(max732x_of_table),
741 },
742 .probe = max732x_probe,
743 .remove = max732x_remove,
744 .id_table = max732x_id,
745 };
746
747 static int __init max732x_init(void)
748 {
749 return i2c_add_driver(&max732x_driver);
750 }
751
752
753
754 subsys_initcall(max732x_init);
755
756 static void __exit max732x_exit(void)
757 {
758 i2c_del_driver(&max732x_driver);
759 }
760 module_exit(max732x_exit);
761
762 MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>");
763 MODULE_DESCRIPTION("GPIO expander driver for MAX732X");
764 MODULE_LICENSE("GPL");