tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
2 *
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License version 2 and
5 * only version 2 as published by the Free Software Foundation.
6 *
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
15 * 02110-1301, USA.
16 */
17#include <linux/gpio.h>
18#include <linux/i2c.h>
19#include <linux/init.h>
20#include <linux/interrupt.h>
21#include <linux/irq.h>
22#include <linux/module.h>
23#include <linux/mutex.h>
24#include <linux/slab.h>
25#include <linux/i2c/sx150x.h>
26#include <linux/of.h>
27#include <linux/of_address.h>
28#include <linux/of_irq.h>
29#include <linux/of_gpio.h>
30#include <linux/of_device.h>
31
32#define NO_UPDATE_PENDING -1
33
34/* The chip models of sx150x */
35#define SX150X_123 0
36#define SX150X_456 1
37#define SX150X_789 2
38
39struct sx150x_123_pri {
40 u8 reg_pld_mode;
41 u8 reg_pld_table0;
42 u8 reg_pld_table1;
43 u8 reg_pld_table2;
44 u8 reg_pld_table3;
45 u8 reg_pld_table4;
46 u8 reg_advance;
47};
48
49struct sx150x_456_pri {
50 u8 reg_pld_mode;
51 u8 reg_pld_table0;
52 u8 reg_pld_table1;
53 u8 reg_pld_table2;
54 u8 reg_pld_table3;
55 u8 reg_pld_table4;
56 u8 reg_advance;
57};
58
59struct sx150x_789_pri {
60 u8 reg_drain;
61 u8 reg_polarity;
62 u8 reg_clock;
63 u8 reg_misc;
64 u8 reg_reset;
65 u8 ngpios;
66};
67
68struct sx150x_device_data {
69 u8 model;
70 u8 reg_pullup;
71 u8 reg_pulldn;
72 u8 reg_dir;
73 u8 reg_data;
74 u8 reg_irq_mask;
75 u8 reg_irq_src;
76 u8 reg_sense;
77 u8 ngpios;
78 union {
79 struct sx150x_123_pri x123;
80 struct sx150x_456_pri x456;
81 struct sx150x_789_pri x789;
82 } pri;
83};
84
85struct sx150x_chip {
86 struct gpio_chip gpio_chip;
87 struct i2c_client *client;
88 const struct sx150x_device_data *dev_cfg;
89 int irq_summary;
90 int irq_base;
91 int irq_update;
92 u32 irq_sense;
93 u32 irq_masked;
94 u32 dev_sense;
95 u32 dev_masked;
96 struct irq_chip irq_chip;
97 struct mutex lock;
98};
99
100static const struct sx150x_device_data sx150x_devices[] = {
101 [0] = { /* sx1508q */
102 .model = SX150X_789,
103 .reg_pullup = 0x03,
104 .reg_pulldn = 0x04,
105 .reg_dir = 0x07,
106 .reg_data = 0x08,
107 .reg_irq_mask = 0x09,
108 .reg_irq_src = 0x0c,
109 .reg_sense = 0x0b,
110 .pri.x789 = {
111 .reg_drain = 0x05,
112 .reg_polarity = 0x06,
113 .reg_clock = 0x0f,
114 .reg_misc = 0x10,
115 .reg_reset = 0x7d,
116 },
117 .ngpios = 8,
118 },
119 [1] = { /* sx1509q */
120 .model = SX150X_789,
121 .reg_pullup = 0x07,
122 .reg_pulldn = 0x09,
123 .reg_dir = 0x0f,
124 .reg_data = 0x11,
125 .reg_irq_mask = 0x13,
126 .reg_irq_src = 0x19,
127 .reg_sense = 0x17,
128 .pri.x789 = {
129 .reg_drain = 0x0b,
130 .reg_polarity = 0x0d,
131 .reg_clock = 0x1e,
132 .reg_misc = 0x1f,
133 .reg_reset = 0x7d,
134 },
135 .ngpios = 16
136 },
137 [2] = { /* sx1506q */
138 .model = SX150X_456,
139 .reg_pullup = 0x05,
140 .reg_pulldn = 0x07,
141 .reg_dir = 0x03,
142 .reg_data = 0x01,
143 .reg_irq_mask = 0x09,
144 .reg_irq_src = 0x0f,
145 .reg_sense = 0x0d,
146 .pri.x456 = {
147 .reg_pld_mode = 0x21,
148 .reg_pld_table0 = 0x23,
149 .reg_pld_table1 = 0x25,
150 .reg_pld_table2 = 0x27,
151 .reg_pld_table3 = 0x29,
152 .reg_pld_table4 = 0x2b,
153 .reg_advance = 0xad,
154 },
155 .ngpios = 16
156 },
157 [3] = { /* sx1502q */
158 .model = SX150X_123,
159 .reg_pullup = 0x02,
160 .reg_pulldn = 0x03,
161 .reg_dir = 0x01,
162 .reg_data = 0x00,
163 .reg_irq_mask = 0x05,
164 .reg_irq_src = 0x08,
165 .reg_sense = 0x07,
166 .pri.x123 = {
167 .reg_pld_mode = 0x10,
168 .reg_pld_table0 = 0x11,
169 .reg_pld_table1 = 0x12,
170 .reg_pld_table2 = 0x13,
171 .reg_pld_table3 = 0x14,
172 .reg_pld_table4 = 0x15,
173 .reg_advance = 0xad,
174 },
175 .ngpios = 8,
176 },
177};
178
179static const struct i2c_device_id sx150x_id[] = {
180 {"sx1508q", 0},
181 {"sx1509q", 1},
182 {"sx1506q", 2},
183 {"sx1502q", 3},
184 {}
185};
186MODULE_DEVICE_TABLE(i2c, sx150x_id);
187
188static const struct of_device_id sx150x_of_match[] = {
189 { .compatible = "semtech,sx1508q" },
190 { .compatible = "semtech,sx1509q" },
191 { .compatible = "semtech,sx1506q" },
192 { .compatible = "semtech,sx1502q" },
193 {},
194};
195MODULE_DEVICE_TABLE(of, sx150x_of_match);
196
197static s32 sx150x_i2c_write(struct i2c_client *client, u8 reg, u8 val)
198{
199 s32 err = i2c_smbus_write_byte_data(client, reg, val);
200
201 if (err < 0)
202 dev_warn(&client->dev,
203 "i2c write fail: can't write %02x to %02x: %d\n",
204 val, reg, err);
205 return err;
206}
207
208static s32 sx150x_i2c_read(struct i2c_client *client, u8 reg, u8 *val)
209{
210 s32 err = i2c_smbus_read_byte_data(client, reg);
211
212 if (err >= 0)
213 *val = err;
214 else
215 dev_warn(&client->dev,
216 "i2c read fail: can't read from %02x: %d\n",
217 reg, err);
218 return err;
219}
220
221static inline bool offset_is_oscio(struct sx150x_chip *chip, unsigned offset)
222{
223 return (chip->dev_cfg->ngpios == offset);
224}
225
226/*
227 * These utility functions solve the common problem of locating and setting
228 * configuration bits. Configuration bits are grouped into registers
229 * whose indexes increase downwards. For example, with eight-bit registers,
230 * sixteen gpios would have their config bits grouped in the following order:
231 * REGISTER N-1 [ f e d c b a 9 8 ]
232 * N [ 7 6 5 4 3 2 1 0 ]
233 *
234 * For multi-bit configurations, the pattern gets wider:
235 * REGISTER N-3 [ f f e e d d c c ]
236 * N-2 [ b b a a 9 9 8 8 ]
237 * N-1 [ 7 7 6 6 5 5 4 4 ]
238 * N [ 3 3 2 2 1 1 0 0 ]
239 *
240 * Given the address of the starting register 'N', the index of the gpio
241 * whose configuration we seek to change, and the width in bits of that
242 * configuration, these functions allow us to locate the correct
243 * register and mask the correct bits.
244 */
245static inline void sx150x_find_cfg(u8 offset, u8 width,
246 u8 *reg, u8 *mask, u8 *shift)
247{
248 *reg -= offset * width / 8;
249 *mask = (1 << width) - 1;
250 *shift = (offset * width) % 8;
251 *mask <<= *shift;
252}
253
254static s32 sx150x_write_cfg(struct sx150x_chip *chip,
255 u8 offset, u8 width, u8 reg, u8 val)
256{
257 u8 mask;
258 u8 data;
259 u8 shift;
260 s32 err;
261
262 sx150x_find_cfg(offset, width, ®, &mask, &shift);
263 err = sx150x_i2c_read(chip->client, reg, &data);
264 if (err < 0)
265 return err;
266
267 data &= ~mask;
268 data |= (val << shift) & mask;
269 return sx150x_i2c_write(chip->client, reg, data);
270}
271
272static int sx150x_get_io(struct sx150x_chip *chip, unsigned offset)
273{
274 u8 reg = chip->dev_cfg->reg_data;
275 u8 mask;
276 u8 data;
277 u8 shift;
278 s32 err;
279
280 sx150x_find_cfg(offset, 1, ®, &mask, &shift);
281 err = sx150x_i2c_read(chip->client, reg, &data);
282 if (err >= 0)
283 err = (data & mask) != 0 ? 1 : 0;
284
285 return err;
286}
287
288static void sx150x_set_oscio(struct sx150x_chip *chip, int val)
289{
290 sx150x_i2c_write(chip->client,
291 chip->dev_cfg->pri.x789.reg_clock,
292 (val ? 0x1f : 0x10));
293}
294
295static void sx150x_set_io(struct sx150x_chip *chip, unsigned offset, int val)
296{
297 sx150x_write_cfg(chip,
298 offset,
299 1,
300 chip->dev_cfg->reg_data,
301 (val ? 1 : 0));
302}
303
304static int sx150x_io_input(struct sx150x_chip *chip, unsigned offset)
305{
306 return sx150x_write_cfg(chip,
307 offset,
308 1,
309 chip->dev_cfg->reg_dir,
310 1);
311}
312
313static int sx150x_io_output(struct sx150x_chip *chip, unsigned offset, int val)
314{
315 int err;
316
317 err = sx150x_write_cfg(chip,
318 offset,
319 1,
320 chip->dev_cfg->reg_data,
321 (val ? 1 : 0));
322 if (err >= 0)
323 err = sx150x_write_cfg(chip,
324 offset,
325 1,
326 chip->dev_cfg->reg_dir,
327 0);
328 return err;
329}
330
331static int sx150x_gpio_get(struct gpio_chip *gc, unsigned offset)
332{
333 struct sx150x_chip *chip = gpiochip_get_data(gc);
334 int status = -EINVAL;
335
336 if (!offset_is_oscio(chip, offset)) {
337 mutex_lock(&chip->lock);
338 status = sx150x_get_io(chip, offset);
339 mutex_unlock(&chip->lock);
340 }
341
342 return (status < 0) ? status : !!status;
343}
344
345static void sx150x_gpio_set(struct gpio_chip *gc, unsigned offset, int val)
346{
347 struct sx150x_chip *chip = gpiochip_get_data(gc);
348
349 mutex_lock(&chip->lock);
350 if (offset_is_oscio(chip, offset))
351 sx150x_set_oscio(chip, val);
352 else
353 sx150x_set_io(chip, offset, val);
354 mutex_unlock(&chip->lock);
355}
356
357static int sx150x_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
358{
359 struct sx150x_chip *chip = gpiochip_get_data(gc);
360 int status = -EINVAL;
361
362 if (!offset_is_oscio(chip, offset)) {
363 mutex_lock(&chip->lock);
364 status = sx150x_io_input(chip, offset);
365 mutex_unlock(&chip->lock);
366 }
367 return status;
368}
369
370static int sx150x_gpio_direction_output(struct gpio_chip *gc,
371 unsigned offset,
372 int val)
373{
374 struct sx150x_chip *chip = gpiochip_get_data(gc);
375 int status = 0;
376
377 if (!offset_is_oscio(chip, offset)) {
378 mutex_lock(&chip->lock);
379 status = sx150x_io_output(chip, offset, val);
380 mutex_unlock(&chip->lock);
381 }
382 return status;
383}
384
385static void sx150x_irq_mask(struct irq_data *d)
386{
387 struct sx150x_chip *chip = gpiochip_get_data(irq_data_get_irq_chip_data(d));
388 unsigned n = d->hwirq;
389
390 chip->irq_masked |= (1 << n);
391 chip->irq_update = n;
392}
393
394static void sx150x_irq_unmask(struct irq_data *d)
395{
396 struct sx150x_chip *chip = gpiochip_get_data(irq_data_get_irq_chip_data(d));
397 unsigned n = d->hwirq;
398
399 chip->irq_masked &= ~(1 << n);
400 chip->irq_update = n;
401}
402
403static int sx150x_irq_set_type(struct irq_data *d, unsigned int flow_type)
404{
405 struct sx150x_chip *chip = gpiochip_get_data(irq_data_get_irq_chip_data(d));
406 unsigned n, val = 0;
407
408 if (flow_type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
409 return -EINVAL;
410
411 n = d->hwirq;
412
413 if (flow_type & IRQ_TYPE_EDGE_RISING)
414 val |= 0x1;
415 if (flow_type & IRQ_TYPE_EDGE_FALLING)
416 val |= 0x2;
417
418 chip->irq_sense &= ~(3UL << (n * 2));
419 chip->irq_sense |= val << (n * 2);
420 chip->irq_update = n;
421 return 0;
422}
423
424static irqreturn_t sx150x_irq_thread_fn(int irq, void *dev_id)
425{
426 struct sx150x_chip *chip = (struct sx150x_chip *)dev_id;
427 unsigned nhandled = 0;
428 unsigned sub_irq;
429 unsigned n;
430 s32 err;
431 u8 val;
432 int i;
433
434 for (i = (chip->dev_cfg->ngpios / 8) - 1; i >= 0; --i) {
435 err = sx150x_i2c_read(chip->client,
436 chip->dev_cfg->reg_irq_src - i,
437 &val);
438 if (err < 0)
439 continue;
440
441 sx150x_i2c_write(chip->client,
442 chip->dev_cfg->reg_irq_src - i,
443 val);
444 for (n = 0; n < 8; ++n) {
445 if (val & (1 << n)) {
446 sub_irq = irq_find_mapping(
447 chip->gpio_chip.irqdomain,
448 (i * 8) + n);
449 handle_nested_irq(sub_irq);
450 ++nhandled;
451 }
452 }
453 }
454
455 return (nhandled > 0 ? IRQ_HANDLED : IRQ_NONE);
456}
457
458static void sx150x_irq_bus_lock(struct irq_data *d)
459{
460 struct sx150x_chip *chip = gpiochip_get_data(irq_data_get_irq_chip_data(d));
461
462 mutex_lock(&chip->lock);
463}
464
465static void sx150x_irq_bus_sync_unlock(struct irq_data *d)
466{
467 struct sx150x_chip *chip = gpiochip_get_data(irq_data_get_irq_chip_data(d));
468 unsigned n;
469
470 if (chip->irq_update == NO_UPDATE_PENDING)
471 goto out;
472
473 n = chip->irq_update;
474 chip->irq_update = NO_UPDATE_PENDING;
475
476 /* Avoid updates if nothing changed */
477 if (chip->dev_sense == chip->irq_sense &&
478 chip->dev_masked == chip->irq_masked)
479 goto out;
480
481 chip->dev_sense = chip->irq_sense;
482 chip->dev_masked = chip->irq_masked;
483
484 if (chip->irq_masked & (1 << n)) {
485 sx150x_write_cfg(chip, n, 1, chip->dev_cfg->reg_irq_mask, 1);
486 sx150x_write_cfg(chip, n, 2, chip->dev_cfg->reg_sense, 0);
487 } else {
488 sx150x_write_cfg(chip, n, 1, chip->dev_cfg->reg_irq_mask, 0);
489 sx150x_write_cfg(chip, n, 2, chip->dev_cfg->reg_sense,
490 chip->irq_sense >> (n * 2));
491 }
492out:
493 mutex_unlock(&chip->lock);
494}
495
496static void sx150x_init_chip(struct sx150x_chip *chip,
497 struct i2c_client *client,
498 kernel_ulong_t driver_data,
499 struct sx150x_platform_data *pdata)
500{
501 mutex_init(&chip->lock);
502
503 chip->client = client;
504 chip->dev_cfg = &sx150x_devices[driver_data];
505 chip->gpio_chip.parent = &client->dev;
506 chip->gpio_chip.label = client->name;
507 chip->gpio_chip.direction_input = sx150x_gpio_direction_input;
508 chip->gpio_chip.direction_output = sx150x_gpio_direction_output;
509 chip->gpio_chip.get = sx150x_gpio_get;
510 chip->gpio_chip.set = sx150x_gpio_set;
511 chip->gpio_chip.base = pdata->gpio_base;
512 chip->gpio_chip.can_sleep = true;
513 chip->gpio_chip.ngpio = chip->dev_cfg->ngpios;
514#ifdef CONFIG_OF_GPIO
515 chip->gpio_chip.of_node = client->dev.of_node;
516 chip->gpio_chip.of_gpio_n_cells = 2;
517#endif
518 if (pdata->oscio_is_gpo)
519 ++chip->gpio_chip.ngpio;
520
521 chip->irq_chip.name = client->name;
522 chip->irq_chip.irq_mask = sx150x_irq_mask;
523 chip->irq_chip.irq_unmask = sx150x_irq_unmask;
524 chip->irq_chip.irq_set_type = sx150x_irq_set_type;
525 chip->irq_chip.irq_bus_lock = sx150x_irq_bus_lock;
526 chip->irq_chip.irq_bus_sync_unlock = sx150x_irq_bus_sync_unlock;
527 chip->irq_summary = -1;
528 chip->irq_base = -1;
529 chip->irq_masked = ~0;
530 chip->irq_sense = 0;
531 chip->dev_masked = ~0;
532 chip->dev_sense = 0;
533 chip->irq_update = NO_UPDATE_PENDING;
534}
535
536static int sx150x_init_io(struct sx150x_chip *chip, u8 base, u16 cfg)
537{
538 int err = 0;
539 unsigned n;
540
541 for (n = 0; err >= 0 && n < (chip->dev_cfg->ngpios / 8); ++n)
542 err = sx150x_i2c_write(chip->client, base - n, cfg >> (n * 8));
543 return err;
544}
545
546static int sx150x_reset(struct sx150x_chip *chip)
547{
548 int err;
549
550 err = i2c_smbus_write_byte_data(chip->client,
551 chip->dev_cfg->pri.x789.reg_reset,
552 0x12);
553 if (err < 0)
554 return err;
555
556 err = i2c_smbus_write_byte_data(chip->client,
557 chip->dev_cfg->pri.x789.reg_reset,
558 0x34);
559 return err;
560}
561
562static int sx150x_init_hw(struct sx150x_chip *chip,
563 struct sx150x_platform_data *pdata)
564{
565 int err = 0;
566
567 if (pdata->reset_during_probe) {
568 err = sx150x_reset(chip);
569 if (err < 0)
570 return err;
571 }
572
573 if (chip->dev_cfg->model == SX150X_789)
574 err = sx150x_i2c_write(chip->client,
575 chip->dev_cfg->pri.x789.reg_misc,
576 0x01);
577 else if (chip->dev_cfg->model == SX150X_456)
578 err = sx150x_i2c_write(chip->client,
579 chip->dev_cfg->pri.x456.reg_advance,
580 0x04);
581 else
582 err = sx150x_i2c_write(chip->client,
583 chip->dev_cfg->pri.x123.reg_advance,
584 0x00);
585 if (err < 0)
586 return err;
587
588 err = sx150x_init_io(chip, chip->dev_cfg->reg_pullup,
589 pdata->io_pullup_ena);
590 if (err < 0)
591 return err;
592
593 err = sx150x_init_io(chip, chip->dev_cfg->reg_pulldn,
594 pdata->io_pulldn_ena);
595 if (err < 0)
596 return err;
597
598 if (chip->dev_cfg->model == SX150X_789) {
599 err = sx150x_init_io(chip,
600 chip->dev_cfg->pri.x789.reg_drain,
601 pdata->io_open_drain_ena);
602 if (err < 0)
603 return err;
604
605 err = sx150x_init_io(chip,
606 chip->dev_cfg->pri.x789.reg_polarity,
607 pdata->io_polarity);
608 if (err < 0)
609 return err;
610 } else if (chip->dev_cfg->model == SX150X_456) {
611 /* Set all pins to work in normal mode */
612 err = sx150x_init_io(chip,
613 chip->dev_cfg->pri.x456.reg_pld_mode,
614 0);
615 if (err < 0)
616 return err;
617 } else {
618 /* Set all pins to work in normal mode */
619 err = sx150x_init_io(chip,
620 chip->dev_cfg->pri.x123.reg_pld_mode,
621 0);
622 if (err < 0)
623 return err;
624 }
625
626
627 if (pdata->oscio_is_gpo)
628 sx150x_set_oscio(chip, 0);
629
630 return err;
631}
632
633static int sx150x_install_irq_chip(struct sx150x_chip *chip,
634 int irq_summary,
635 int irq_base)
636{
637 int err;
638
639 chip->irq_summary = irq_summary;
640 chip->irq_base = irq_base;
641
642 /* Add gpio chip to irq subsystem */
643 err = gpiochip_irqchip_add(&chip->gpio_chip,
644 &chip->irq_chip, chip->irq_base,
645 handle_edge_irq, IRQ_TYPE_EDGE_BOTH);
646 if (err) {
647 dev_err(&chip->client->dev,
648 "could not connect irqchip to gpiochip\n");
649 return err;
650 }
651
652 err = devm_request_threaded_irq(&chip->client->dev,
653 irq_summary, NULL, sx150x_irq_thread_fn,
654 IRQF_ONESHOT | IRQF_SHARED | IRQF_TRIGGER_FALLING,
655 chip->irq_chip.name, chip);
656 if (err < 0) {
657 chip->irq_summary = -1;
658 chip->irq_base = -1;
659 }
660
661 return err;
662}
663
664static int sx150x_probe(struct i2c_client *client,
665 const struct i2c_device_id *id)
666{
667 static const u32 i2c_funcs = I2C_FUNC_SMBUS_BYTE_DATA |
668 I2C_FUNC_SMBUS_WRITE_WORD_DATA;
669 struct sx150x_platform_data *pdata;
670 struct sx150x_chip *chip;
671 int rc;
672
673 pdata = dev_get_platdata(&client->dev);
674 if (!pdata)
675 return -EINVAL;
676
677 if (!i2c_check_functionality(client->adapter, i2c_funcs))
678 return -ENOSYS;
679
680 chip = devm_kzalloc(&client->dev,
681 sizeof(struct sx150x_chip), GFP_KERNEL);
682 if (!chip)
683 return -ENOMEM;
684
685 sx150x_init_chip(chip, client, id->driver_data, pdata);
686 rc = sx150x_init_hw(chip, pdata);
687 if (rc < 0)
688 return rc;
689
690 rc = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
691 if (rc)
692 return rc;
693
694 if (pdata->irq_summary >= 0) {
695 rc = sx150x_install_irq_chip(chip,
696 pdata->irq_summary,
697 pdata->irq_base);
698 if (rc < 0)
699 return rc;
700 }
701
702 i2c_set_clientdata(client, chip);
703
704 return 0;
705}
706
707static struct i2c_driver sx150x_driver = {
708 .driver = {
709 .name = "sx150x",
710 .of_match_table = of_match_ptr(sx150x_of_match),
711 },
712 .probe = sx150x_probe,
713 .id_table = sx150x_id,
714};
715
716static int __init sx150x_init(void)
717{
718 return i2c_add_driver(&sx150x_driver);
719}
720subsys_initcall(sx150x_init);
721
722static void __exit sx150x_exit(void)
723{
724 return i2c_del_driver(&sx150x_driver);
725}
726module_exit(sx150x_exit);
727
728MODULE_AUTHOR("Gregory Bean <gbean@codeaurora.org>");
729MODULE_DESCRIPTION("Driver for Semtech SX150X I2C GPIO Expanders");
730MODULE_LICENSE("GPL v2");