1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * MAX732x I2C Port Expander with 8/16 I/O
4 *
5 * Copyright (C) 2007 Marvell International Ltd.
6 * Copyright (C) 2008 Jack Ren <jack.ren@marvell.com>
7 * Copyright (C) 2008 Eric Miao <eric.miao@marvell.com>
8 * Copyright (C) 2015 Linus Walleij <linus.walleij@linaro.org>
9 *
10 * Derived from drivers/gpio/pca953x.c
11 */
12
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
22 /*
23 * Each port of MAX732x (including MAX7319) falls into one of the
24 * following three types:
25 *
26 * - Push Pull Output
27 * - Input
28 * - Open Drain I/O
29 *
30 * designated by 'O', 'I' and 'P' individually according to MAXIM's
31 * datasheets. 'I' and 'P' ports are interrupt capables, some with
32 * a dedicated interrupt mask.
33 *
34 * There are two groups of I/O ports, each group usually includes
35 * up to 8 I/O ports, and is accessed by a specific I2C address:
36 *
37 * - Group A : by I2C address 0b'110xxxx
38 * - Group B : by I2C address 0b'101xxxx
39 *
40 * where 'xxxx' is decided by the connections of pin AD2/AD0. The
41 * address used also affects the initial state of output signals.
42 *
43 * Within each group of ports, there are five known combinations of
44 * I/O ports: 4I4O, 4P4O, 8I, 8P, 8O, see the definitions below for
45 * the detailed organization of these ports. Only Goup A is interrupt
46 * capable.
47 *
48 * GPIO numbers start from 'gpio_base + 0' to 'gpio_base + 8/16',
49 * and GPIOs from GROUP_A are numbered before those from GROUP_B
50 * (if there are two groups).
51 *
52 * NOTE: MAX7328/MAX7329 are drop-in replacements for PCF8574/a, so
53 * they are not supported by this driver.
54 */
55
56 #define PORT_NONE 0x0 /* '/' No Port */
57 #define PORT_OUTPUT 0x1 /* 'O' Push-Pull, Output Only */
58 #define PORT_INPUT 0x2 /* 'I' Input Only */
59 #define PORT_OPENDRAIN 0x3 /* 'P' Open-Drain, I/O */
60
61 #define IO_4I4O 0x5AA5 /* O7 O6 I5 I4 I3 I2 O1 O0 */
62 #define IO_4P4O 0x5FF5 /* O7 O6 P5 P4 P3 P2 O1 O0 */
63 #define IO_8I 0xAAAA /* I7 I6 I5 I4 I3 I2 I1 I0 */
64 #define IO_8P 0xFFFF /* P7 P6 P5 P4 P3 P2 P1 P0 */
65 #define IO_8O 0x5555 /* O7 O6 O5 O4 O3 O2 O1 O0 */
66
67 #define GROUP_A(x) ((x) & 0xffff) /* I2C Addr: 0b'110xxxx */
68 #define GROUP_B(x) ((x) << 16) /* I2C Addr: 0b'101xxxx */
69
70 #define INT_NONE 0x0 /* No interrupt capability */
71 #define INT_NO_MASK 0x1 /* Has interrupts, no mask */
72 #define INT_INDEP_MASK 0x2 /* Has interrupts, independent mask */
73 #define INT_MERGED_MASK 0x3 /* Has interrupts, merged mask */
74
75 #define INT_CAPS(x) (((uint64_t)(x)) << 32)
76
77 enum {
78 MAX7319,
79 MAX7320,
80 MAX7321,
81 MAX7322,
82 MAX7323,
83 MAX7324,
84 MAX7325,
85 MAX7326,
86 MAX7327,
87 };
88
89 static uint64_t max732x_features[] = {
90 [MAX7319] = GROUP_A(IO_8I) | INT_CAPS(INT_MERGED_MASK),
91 [MAX7320] = GROUP_B(IO_8O),
92 [MAX7321] = GROUP_A(IO_8P) | INT_CAPS(INT_NO_MASK),
93 [MAX7322] = GROUP_A(IO_4I4O) | INT_CAPS(INT_MERGED_MASK),
94 [MAX7323] = GROUP_A(IO_4P4O) | INT_CAPS(INT_INDEP_MASK),
95 [MAX7324] = GROUP_A(IO_8I) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK),
96 [MAX7325] = GROUP_A(IO_8P) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK),
97 [MAX7326] = GROUP_A(IO_4I4O) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK),
98 [MAX7327] = GROUP_A(IO_4P4O) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK),
99 };
100
101 static const struct i2c_device_id max732x_id[] = {
102 { "max7319", MAX7319 },
103 { "max7320", MAX7320 },
104 { "max7321", MAX7321 },
105 { "max7322", MAX7322 },
106 { "max7323", MAX7323 },
107 { "max7324", MAX7324 },
108 { "max7325", MAX7325 },
109 { "max7326", MAX7326 },
110 { "max7327", MAX7327 },
111 { },
112 };
113 MODULE_DEVICE_TABLE(i2c, max732x_id);
114
115 static const struct of_device_id max732x_of_table[] = {
116 { .compatible = "maxim,max7319" },
117 { .compatible = "maxim,max7320" },
118 { .compatible = "maxim,max7321" },
119 { .compatible = "maxim,max7322" },
120 { .compatible = "maxim,max7323" },
121 { .compatible = "maxim,max7324" },
122 { .compatible = "maxim,max7325" },
123 { .compatible = "maxim,max7326" },
124 { .compatible = "maxim,max7327" },
125 { }
126 };
127 MODULE_DEVICE_TABLE(of, max732x_of_table);
128
129 struct max732x_chip {
130 struct gpio_chip gpio_chip;
131
132 struct i2c_client *client; /* "main" client */
133 struct i2c_client *client_dummy;
134 struct i2c_client *client_group_a;
135 struct i2c_client *client_group_b;
136
137 unsigned int mask_group_a;
138 unsigned int dir_input;
139 unsigned int dir_output;
140
141 struct mutex lock;
142 uint8_t reg_out[2];
143
144 #ifdef CONFIG_GPIO_MAX732X_IRQ
145 struct mutex irq_lock;
146 uint8_t irq_mask;
147 uint8_t irq_mask_cur;
148 uint8_t irq_trig_raise;
149 uint8_t irq_trig_fall;
150 uint8_t irq_features;
151 #endif
152 };
153
max732x_writeb(struct max732x_chip * chip,int group_a,uint8_t val)154 static int max732x_writeb(struct max732x_chip *chip, int group_a, uint8_t val)
155 {
156 struct i2c_client *client;
157 int ret;
158
159 client = group_a ? chip->client_group_a : chip->client_group_b;
160 ret = i2c_smbus_write_byte(client, val);
161 if (ret < 0) {
162 dev_err(&client->dev, "failed writing\n");
163 return ret;
164 }
165
166 return 0;
167 }
168
max732x_readb(struct max732x_chip * chip,int group_a,uint8_t * val)169 static int max732x_readb(struct max732x_chip *chip, int group_a, uint8_t *val)
170 {
171 struct i2c_client *client;
172 int ret;
173
174 client = group_a ? chip->client_group_a : chip->client_group_b;
175 ret = i2c_smbus_read_byte(client);
176 if (ret < 0) {
177 dev_err(&client->dev, "failed reading\n");
178 return ret;
179 }
180
181 *val = (uint8_t)ret;
182 return 0;
183 }
184
is_group_a(struct max732x_chip * chip,unsigned off)185 static inline int is_group_a(struct max732x_chip *chip, unsigned off)
186 {
187 return (1u << off) & chip->mask_group_a;
188 }
189
max732x_gpio_get_value(struct gpio_chip * gc,unsigned off)190 static int max732x_gpio_get_value(struct gpio_chip *gc, unsigned off)
191 {
192 struct max732x_chip *chip = gpiochip_get_data(gc);
193 uint8_t reg_val;
194 int ret;
195
196 ret = max732x_readb(chip, is_group_a(chip, off), ®_val);
197 if (ret < 0)
198 return ret;
199
200 return !!(reg_val & (1u << (off & 0x7)));
201 }
202
max732x_gpio_set_mask(struct gpio_chip * gc,unsigned off,int mask,int val)203 static void max732x_gpio_set_mask(struct gpio_chip *gc, unsigned off, int mask,
204 int val)
205 {
206 struct max732x_chip *chip = gpiochip_get_data(gc);
207 uint8_t reg_out;
208 int ret;
209
210 mutex_lock(&chip->lock);
211
212 reg_out = (off > 7) ? chip->reg_out[1] : chip->reg_out[0];
213 reg_out = (reg_out & ~mask) | (val & mask);
214
215 ret = max732x_writeb(chip, is_group_a(chip, off), reg_out);
216 if (ret < 0)
217 goto out;
218
219 /* update the shadow register then */
220 if (off > 7)
221 chip->reg_out[1] = reg_out;
222 else
223 chip->reg_out[0] = reg_out;
224 out:
225 mutex_unlock(&chip->lock);
226 }
227
max732x_gpio_set_value(struct gpio_chip * gc,unsigned int off,int val)228 static int max732x_gpio_set_value(struct gpio_chip *gc, unsigned int off,
229 int val)
230 {
231 unsigned base = off & ~0x7;
232 uint8_t mask = 1u << (off & 0x7);
233
234 max732x_gpio_set_mask(gc, base, mask, val << (off & 0x7));
235
236 return 0;
237 }
238
max732x_gpio_set_multiple(struct gpio_chip * gc,unsigned long * mask,unsigned long * bits)239 static int max732x_gpio_set_multiple(struct gpio_chip *gc,
240 unsigned long *mask, unsigned long *bits)
241 {
242 unsigned mask_lo = mask[0] & 0xff;
243 unsigned mask_hi = (mask[0] >> 8) & 0xff;
244
245 if (mask_lo)
246 max732x_gpio_set_mask(gc, 0, mask_lo, bits[0] & 0xff);
247 if (mask_hi)
248 max732x_gpio_set_mask(gc, 8, mask_hi, (bits[0] >> 8) & 0xff);
249
250 return 0;
251 }
252
max732x_gpio_direction_input(struct gpio_chip * gc,unsigned off)253 static int max732x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
254 {
255 struct max732x_chip *chip = gpiochip_get_data(gc);
256 unsigned int mask = 1u << off;
257
258 if ((mask & chip->dir_input) == 0) {
259 dev_dbg(&chip->client->dev, "%s port %d is output only\n",
260 chip->client->name, off);
261 return -EACCES;
262 }
263
264 /*
265 * Open-drain pins must be set to high impedance (which is
266 * equivalent to output-high) to be turned into an input.
267 */
268 if ((mask & chip->dir_output))
269 max732x_gpio_set_value(gc, off, 1);
270
271 return 0;
272 }
273
max732x_gpio_direction_output(struct gpio_chip * gc,unsigned off,int val)274 static int max732x_gpio_direction_output(struct gpio_chip *gc,
275 unsigned off, int val)
276 {
277 struct max732x_chip *chip = gpiochip_get_data(gc);
278 unsigned int mask = 1u << off;
279
280 if ((mask & chip->dir_output) == 0) {
281 dev_dbg(&chip->client->dev, "%s port %d is input only\n",
282 chip->client->name, off);
283 return -EACCES;
284 }
285
286 max732x_gpio_set_value(gc, off, val);
287 return 0;
288 }
289
290 #ifdef CONFIG_GPIO_MAX732X_IRQ
max732x_writew(struct max732x_chip * chip,uint16_t val)291 static int max732x_writew(struct max732x_chip *chip, uint16_t val)
292 {
293 int ret;
294
295 val = cpu_to_le16(val);
296
297 ret = i2c_master_send(chip->client_group_a, (char *)&val, 2);
298 if (ret < 0) {
299 dev_err(&chip->client_group_a->dev, "failed writing\n");
300 return ret;
301 }
302
303 return 0;
304 }
305
max732x_readw(struct max732x_chip * chip,uint16_t * val)306 static int max732x_readw(struct max732x_chip *chip, uint16_t *val)
307 {
308 int ret;
309
310 ret = i2c_master_recv(chip->client_group_a, (char *)val, 2);
311 if (ret < 0) {
312 dev_err(&chip->client_group_a->dev, "failed reading\n");
313 return ret;
314 }
315
316 *val = le16_to_cpu(*val);
317 return 0;
318 }
319
max732x_irq_update_mask(struct max732x_chip * chip)320 static void max732x_irq_update_mask(struct max732x_chip *chip)
321 {
322 uint16_t msg;
323
324 if (chip->irq_mask == chip->irq_mask_cur)
325 return;
326
327 chip->irq_mask = chip->irq_mask_cur;
328
329 if (chip->irq_features == INT_NO_MASK)
330 return;
331
332 mutex_lock(&chip->lock);
333
334 switch (chip->irq_features) {
335 case INT_INDEP_MASK:
336 msg = (chip->irq_mask << 8) | chip->reg_out[0];
337 max732x_writew(chip, msg);
338 break;
339
340 case INT_MERGED_MASK:
341 msg = chip->irq_mask | chip->reg_out[0];
342 max732x_writeb(chip, 1, (uint8_t)msg);
343 break;
344 }
345
346 mutex_unlock(&chip->lock);
347 }
348
max732x_irq_mask(struct irq_data * d)349 static void max732x_irq_mask(struct irq_data *d)
350 {
351 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
352 struct max732x_chip *chip = gpiochip_get_data(gc);
353
354 chip->irq_mask_cur &= ~(1 << d->hwirq);
355 gpiochip_disable_irq(gc, irqd_to_hwirq(d));
356 }
357
max732x_irq_unmask(struct irq_data * d)358 static void max732x_irq_unmask(struct irq_data *d)
359 {
360 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
361 struct max732x_chip *chip = gpiochip_get_data(gc);
362
363 gpiochip_enable_irq(gc, irqd_to_hwirq(d));
364 chip->irq_mask_cur |= 1 << d->hwirq;
365 }
366
max732x_irq_bus_lock(struct irq_data * d)367 static void max732x_irq_bus_lock(struct irq_data *d)
368 {
369 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
370 struct max732x_chip *chip = gpiochip_get_data(gc);
371
372 mutex_lock(&chip->irq_lock);
373 chip->irq_mask_cur = chip->irq_mask;
374 }
375
max732x_irq_bus_sync_unlock(struct irq_data * d)376 static void max732x_irq_bus_sync_unlock(struct irq_data *d)
377 {
378 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
379 struct max732x_chip *chip = gpiochip_get_data(gc);
380 uint16_t new_irqs;
381 uint16_t level;
382
383 max732x_irq_update_mask(chip);
384
385 new_irqs = chip->irq_trig_fall | chip->irq_trig_raise;
386 while (new_irqs) {
387 level = __ffs(new_irqs);
388 max732x_gpio_direction_input(&chip->gpio_chip, level);
389 new_irqs &= ~(1 << level);
390 }
391
392 mutex_unlock(&chip->irq_lock);
393 }
394
max732x_irq_set_type(struct irq_data * d,unsigned int type)395 static int max732x_irq_set_type(struct irq_data *d, unsigned int type)
396 {
397 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
398 struct max732x_chip *chip = gpiochip_get_data(gc);
399 uint16_t off = d->hwirq;
400 uint16_t mask = 1 << off;
401
402 if (!(mask & chip->dir_input)) {
403 dev_dbg(&chip->client->dev, "%s port %d is output only\n",
404 chip->client->name, off);
405 return -EACCES;
406 }
407
408 if (!(type & IRQ_TYPE_EDGE_BOTH)) {
409 dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
410 d->irq, type);
411 return -EINVAL;
412 }
413
414 if (type & IRQ_TYPE_EDGE_FALLING)
415 chip->irq_trig_fall |= mask;
416 else
417 chip->irq_trig_fall &= ~mask;
418
419 if (type & IRQ_TYPE_EDGE_RISING)
420 chip->irq_trig_raise |= mask;
421 else
422 chip->irq_trig_raise &= ~mask;
423
424 return 0;
425 }
426
max732x_irq_set_wake(struct irq_data * data,unsigned int on)427 static int max732x_irq_set_wake(struct irq_data *data, unsigned int on)
428 {
429 struct max732x_chip *chip = irq_data_get_irq_chip_data(data);
430
431 irq_set_irq_wake(chip->client->irq, on);
432 return 0;
433 }
434
435 static const struct irq_chip max732x_irq_chip = {
436 .name = "max732x",
437 .irq_mask = max732x_irq_mask,
438 .irq_unmask = max732x_irq_unmask,
439 .irq_bus_lock = max732x_irq_bus_lock,
440 .irq_bus_sync_unlock = max732x_irq_bus_sync_unlock,
441 .irq_set_type = max732x_irq_set_type,
442 .irq_set_wake = max732x_irq_set_wake,
443 .flags = IRQCHIP_IMMUTABLE,
444 GPIOCHIP_IRQ_RESOURCE_HELPERS,
445 };
446
max732x_irq_pending(struct max732x_chip * chip)447 static uint8_t max732x_irq_pending(struct max732x_chip *chip)
448 {
449 uint8_t cur_stat;
450 uint8_t old_stat;
451 uint8_t trigger;
452 uint8_t pending;
453 uint16_t status;
454 int ret;
455
456 ret = max732x_readw(chip, &status);
457 if (ret)
458 return 0;
459
460 trigger = status >> 8;
461 trigger &= chip->irq_mask;
462
463 if (!trigger)
464 return 0;
465
466 cur_stat = status & 0xFF;
467 cur_stat &= chip->irq_mask;
468
469 old_stat = cur_stat ^ trigger;
470
471 pending = (old_stat & chip->irq_trig_fall) |
472 (cur_stat & chip->irq_trig_raise);
473 pending &= trigger;
474
475 return pending;
476 }
477
max732x_irq_handler(int irq,void * devid)478 static irqreturn_t max732x_irq_handler(int irq, void *devid)
479 {
480 struct max732x_chip *chip = devid;
481 uint8_t pending;
482 uint8_t level;
483
484 pending = max732x_irq_pending(chip);
485
486 if (!pending)
487 return IRQ_HANDLED;
488
489 do {
490 level = __ffs(pending);
491 handle_nested_irq(irq_find_mapping(chip->gpio_chip.irq.domain,
492 level));
493
494 pending &= ~(1 << level);
495 } while (pending);
496
497 return IRQ_HANDLED;
498 }
499
max732x_irq_setup(struct max732x_chip * chip,const struct i2c_device_id * id)500 static int max732x_irq_setup(struct max732x_chip *chip,
501 const struct i2c_device_id *id)
502 {
503 struct i2c_client *client = chip->client;
504 int has_irq = max732x_features[id->driver_data] >> 32;
505 int irq_base = 0;
506 int ret;
507
508 if (client->irq && has_irq != INT_NONE) {
509 struct gpio_irq_chip *girq;
510
511 chip->irq_features = has_irq;
512 mutex_init(&chip->irq_lock);
513
514 ret = devm_request_threaded_irq(&client->dev, client->irq,
515 NULL, max732x_irq_handler, IRQF_ONESHOT |
516 IRQF_TRIGGER_FALLING | IRQF_SHARED,
517 dev_name(&client->dev), chip);
518 if (ret) {
519 dev_err(&client->dev, "failed to request irq %d\n",
520 client->irq);
521 return ret;
522 }
523
524 girq = &chip->gpio_chip.irq;
525 gpio_irq_chip_set_chip(girq, &max732x_irq_chip);
526 /* This will let us handle the parent IRQ in the driver */
527 girq->parent_handler = NULL;
528 girq->num_parents = 0;
529 girq->parents = NULL;
530 girq->default_type = IRQ_TYPE_NONE;
531 girq->handler = handle_simple_irq;
532 girq->threaded = true;
533 girq->first = irq_base; /* FIXME: get rid of this */
534 }
535
536 return 0;
537 }
538
539 #else /* CONFIG_GPIO_MAX732X_IRQ */
max732x_irq_setup(struct max732x_chip * chip,const struct i2c_device_id * id)540 static int max732x_irq_setup(struct max732x_chip *chip,
541 const struct i2c_device_id *id)
542 {
543 struct i2c_client *client = chip->client;
544 int has_irq = max732x_features[id->driver_data] >> 32;
545
546 if (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
max732x_setup_gpio(struct max732x_chip * chip,const struct i2c_device_id * id,unsigned gpio_start)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_rv = max732x_gpio_set_value;
589 gc->set_multiple_rv = 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
of_gpio_max732x(struct device * dev)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
max732x_probe(struct i2c_client * client)616 static int max732x_probe(struct i2c_client *client)
617 {
618 const struct i2c_device_id *id = i2c_client_get_device_id(client);
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 = max732x_irq_setup(chip, id);
699 if (ret)
700 return ret;
701
702 ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
703 if (ret)
704 return ret;
705
706 i2c_set_clientdata(client, chip);
707 return 0;
708 }
709
710 static struct i2c_driver max732x_driver = {
711 .driver = {
712 .name = "max732x",
713 .of_match_table = max732x_of_table,
714 },
715 .probe = max732x_probe,
716 .id_table = max732x_id,
717 };
718
max732x_init(void)719 static int __init max732x_init(void)
720 {
721 return i2c_add_driver(&max732x_driver);
722 }
723 /* register after i2c postcore initcall and before
724 * subsys initcalls that may rely on these GPIOs
725 */
726 subsys_initcall(max732x_init);
727
max732x_exit(void)728 static void __exit max732x_exit(void)
729 {
730 i2c_del_driver(&max732x_driver);
731 }
732 module_exit(max732x_exit);
733
734 MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>");
735 MODULE_DESCRIPTION("GPIO expander driver for MAX732X");
736 MODULE_LICENSE("GPL");
737