1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * I2C multiplexer
4 *
5 * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
6 * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
7 *
8 * This module supports the PCA954x and PCA984x series of I2C multiplexer/switch
9 * chips made by NXP Semiconductors.
10 * This includes the:
11 * PCA9540, PCA9542, PCA9543, PCA9544, PCA9545, PCA9546, PCA9547,
12 * PCA9548, PCA9846, PCA9847, PCA9848 and PCA9849.
13 *
14 * It's also compatible to Maxims MAX735x I2C switch chips, which are controlled
15 * as the NXP PCA9548 and the MAX736x chips that act like the PCA9544.
16 *
17 * This includes the:
18 * MAX7356, MAX7357, MAX7358, MAX7367, MAX7368 and MAX7369
19 *
20 * These chips are all controlled via the I2C bus itself, and all have a
21 * single 8-bit register. The upstream "parent" bus fans out to two,
22 * four, or eight downstream busses or channels; which of these
23 * are selected is determined by the chip type and register contents. A
24 * mux can select only one sub-bus at a time; a switch can select any
25 * combination simultaneously.
26 *
27 * Based on:
28 * pca954x.c from Kumar Gala <galak@kernel.crashing.org>
29 * Copyright (C) 2006
30 *
31 * Based on:
32 * pca954x.c from Ken Harrenstien
33 * Copyright (C) 2004 Google, Inc. (Ken Harrenstien)
34 *
35 * Based on:
36 * i2c-virtual_cb.c from Brian Kuschak <bkuschak@yahoo.com>
37 * and
38 * pca9540.c from Jean Delvare <jdelvare@suse.de>.
39 */
40
41 #include <linux/device.h>
42 #include <linux/delay.h>
43 #include <linux/gpio/consumer.h>
44 #include <linux/i2c.h>
45 #include <linux/i2c-mux.h>
46 #include <linux/interrupt.h>
47 #include <linux/irq.h>
48 #include <linux/module.h>
49 #include <linux/pm.h>
50 #include <linux/property.h>
51 #include <linux/regulator/consumer.h>
52 #include <linux/reset.h>
53 #include <linux/slab.h>
54 #include <linux/spinlock.h>
55 #include <dt-bindings/mux/mux.h>
56
57 #define PCA954X_MAX_NCHANS 8
58
59 #define PCA954X_IRQ_OFFSET 4
60
61 /*
62 * MAX7357's configuration register is writeable after POR, but
63 * can be locked by setting the basic mode bit. MAX7358 configuration
64 * register is locked by default and needs to be unlocked first.
65 * The configuration register holds the following settings:
66 */
67 #define MAX7357_CONF_INT_ENABLE BIT(0)
68 #define MAX7357_CONF_FLUSH_OUT BIT(1)
69 #define MAX7357_CONF_RELEASE_INT BIT(2)
70 #define MAX7357_CONF_DISCON_SINGLE_CHAN BIT(4)
71 #define MAX7357_CONF_PRECONNECT_TEST BIT(7)
72
73 #define MAX7357_POR_DEFAULT_CONF MAX7357_CONF_INT_ENABLE
74
75 enum pca_type {
76 max_7356,
77 max_7357,
78 max_7358,
79 max_7367,
80 max_7368,
81 max_7369,
82 pca_9540,
83 pca_9542,
84 pca_9543,
85 pca_9544,
86 pca_9545,
87 pca_9546,
88 pca_9547,
89 pca_9548,
90 pca_9846,
91 pca_9847,
92 pca_9848,
93 pca_9849,
94 };
95
96 struct chip_desc {
97 u8 nchans;
98 u8 enable; /* used for muxes only */
99 u8 has_irq;
100 enum muxtype {
101 pca954x_ismux = 0,
102 pca954x_isswi
103 } muxtype;
104 struct i2c_device_identity id;
105 };
106
107 struct pca954x {
108 const struct chip_desc *chip;
109
110 u8 last_chan; /* last register value */
111 /* MUX_IDLE_AS_IS, MUX_IDLE_DISCONNECT or >= 0 for channel */
112 s32 idle_state;
113
114 struct i2c_client *client;
115
116 struct irq_domain *irq;
117 unsigned int irq_mask;
118 raw_spinlock_t lock;
119 struct regulator *supply;
120
121 struct gpio_desc *reset_gpio;
122 struct reset_control *reset_cont;
123 };
124
125 /* Provide specs for the MAX735x, PCA954x and PCA984x types we know about */
126 static const struct chip_desc chips[] = {
127 [max_7356] = {
128 .nchans = 8,
129 .muxtype = pca954x_isswi,
130 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
131 },
132 [max_7357] = {
133 .nchans = 8,
134 .muxtype = pca954x_isswi,
135 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
136 /*
137 * No interrupt controller support. The interrupt
138 * provides information about stuck channels.
139 */
140 },
141 [max_7358] = {
142 .nchans = 8,
143 .muxtype = pca954x_isswi,
144 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
145 /*
146 * No interrupt controller support. The interrupt
147 * provides information about stuck channels.
148 */
149 },
150 [max_7367] = {
151 .nchans = 4,
152 .muxtype = pca954x_isswi,
153 .has_irq = 1,
154 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
155 },
156 [max_7368] = {
157 .nchans = 4,
158 .muxtype = pca954x_isswi,
159 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
160 },
161 [max_7369] = {
162 .nchans = 4,
163 .enable = 0x4,
164 .muxtype = pca954x_ismux,
165 .has_irq = 1,
166 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
167 },
168 [pca_9540] = {
169 .nchans = 2,
170 .enable = 0x4,
171 .muxtype = pca954x_ismux,
172 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
173 },
174 [pca_9542] = {
175 .nchans = 2,
176 .enable = 0x4,
177 .has_irq = 1,
178 .muxtype = pca954x_ismux,
179 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
180 },
181 [pca_9543] = {
182 .nchans = 2,
183 .has_irq = 1,
184 .muxtype = pca954x_isswi,
185 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
186 },
187 [pca_9544] = {
188 .nchans = 4,
189 .enable = 0x4,
190 .has_irq = 1,
191 .muxtype = pca954x_ismux,
192 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
193 },
194 [pca_9545] = {
195 .nchans = 4,
196 .has_irq = 1,
197 .muxtype = pca954x_isswi,
198 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
199 },
200 [pca_9546] = {
201 .nchans = 4,
202 .muxtype = pca954x_isswi,
203 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
204 },
205 [pca_9547] = {
206 .nchans = 8,
207 .enable = 0x8,
208 .muxtype = pca954x_ismux,
209 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
210 },
211 [pca_9548] = {
212 .nchans = 8,
213 .muxtype = pca954x_isswi,
214 .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
215 },
216 [pca_9846] = {
217 .nchans = 4,
218 .muxtype = pca954x_isswi,
219 .id = {
220 .manufacturer_id = I2C_DEVICE_ID_NXP_SEMICONDUCTORS,
221 .part_id = 0x10b,
222 },
223 },
224 [pca_9847] = {
225 .nchans = 8,
226 .enable = 0x8,
227 .muxtype = pca954x_ismux,
228 .id = {
229 .manufacturer_id = I2C_DEVICE_ID_NXP_SEMICONDUCTORS,
230 .part_id = 0x108,
231 },
232 },
233 [pca_9848] = {
234 .nchans = 8,
235 .muxtype = pca954x_isswi,
236 .id = {
237 .manufacturer_id = I2C_DEVICE_ID_NXP_SEMICONDUCTORS,
238 .part_id = 0x10a,
239 },
240 },
241 [pca_9849] = {
242 .nchans = 4,
243 .enable = 0x4,
244 .muxtype = pca954x_ismux,
245 .id = {
246 .manufacturer_id = I2C_DEVICE_ID_NXP_SEMICONDUCTORS,
247 .part_id = 0x109,
248 },
249 },
250 };
251
252 static const struct i2c_device_id pca954x_id[] = {
253 { "max7356", max_7356 },
254 { "max7357", max_7357 },
255 { "max7358", max_7358 },
256 { "max7367", max_7367 },
257 { "max7368", max_7368 },
258 { "max7369", max_7369 },
259 { "pca9540", pca_9540 },
260 { "pca9542", pca_9542 },
261 { "pca9543", pca_9543 },
262 { "pca9544", pca_9544 },
263 { "pca9545", pca_9545 },
264 { "pca9546", pca_9546 },
265 { "pca9547", pca_9547 },
266 { "pca9548", pca_9548 },
267 { "pca9846", pca_9846 },
268 { "pca9847", pca_9847 },
269 { "pca9848", pca_9848 },
270 { "pca9849", pca_9849 },
271 { }
272 };
273 MODULE_DEVICE_TABLE(i2c, pca954x_id);
274
275 static const struct of_device_id pca954x_of_match[] = {
276 { .compatible = "maxim,max7356", .data = &chips[max_7356] },
277 { .compatible = "maxim,max7357", .data = &chips[max_7357] },
278 { .compatible = "maxim,max7358", .data = &chips[max_7358] },
279 { .compatible = "maxim,max7367", .data = &chips[max_7367] },
280 { .compatible = "maxim,max7368", .data = &chips[max_7368] },
281 { .compatible = "maxim,max7369", .data = &chips[max_7369] },
282 { .compatible = "nxp,pca9540", .data = &chips[pca_9540] },
283 { .compatible = "nxp,pca9542", .data = &chips[pca_9542] },
284 { .compatible = "nxp,pca9543", .data = &chips[pca_9543] },
285 { .compatible = "nxp,pca9544", .data = &chips[pca_9544] },
286 { .compatible = "nxp,pca9545", .data = &chips[pca_9545] },
287 { .compatible = "nxp,pca9546", .data = &chips[pca_9546] },
288 { .compatible = "nxp,pca9547", .data = &chips[pca_9547] },
289 { .compatible = "nxp,pca9548", .data = &chips[pca_9548] },
290 { .compatible = "nxp,pca9846", .data = &chips[pca_9846] },
291 { .compatible = "nxp,pca9847", .data = &chips[pca_9847] },
292 { .compatible = "nxp,pca9848", .data = &chips[pca_9848] },
293 { .compatible = "nxp,pca9849", .data = &chips[pca_9849] },
294 {}
295 };
296 MODULE_DEVICE_TABLE(of, pca954x_of_match);
297
298 /* Write to mux register. Don't use i2c_transfer()/i2c_smbus_xfer()
299 for this as they will try to lock adapter a second time */
pca954x_reg_write(struct i2c_adapter * adap,struct i2c_client * client,u8 val)300 static int pca954x_reg_write(struct i2c_adapter *adap,
301 struct i2c_client *client, u8 val)
302 {
303 union i2c_smbus_data dummy;
304
305 return __i2c_smbus_xfer(adap, client->addr, client->flags,
306 I2C_SMBUS_WRITE, val,
307 I2C_SMBUS_BYTE, &dummy);
308 }
309
pca954x_regval(struct pca954x * data,u8 chan)310 static u8 pca954x_regval(struct pca954x *data, u8 chan)
311 {
312 /* We make switches look like muxes, not sure how to be smarter. */
313 if (data->chip->muxtype == pca954x_ismux)
314 return chan | data->chip->enable;
315 else
316 return 1 << chan;
317 }
318
pca954x_select_chan(struct i2c_mux_core * muxc,u32 chan)319 static int pca954x_select_chan(struct i2c_mux_core *muxc, u32 chan)
320 {
321 struct pca954x *data = i2c_mux_priv(muxc);
322 struct i2c_client *client = data->client;
323 u8 regval;
324 int ret = 0;
325
326 regval = pca954x_regval(data, chan);
327 /* Only select the channel if its different from the last channel */
328 if (data->last_chan != regval) {
329 ret = pca954x_reg_write(muxc->parent, client, regval);
330 data->last_chan = ret < 0 ? 0 : regval;
331 }
332
333 return ret;
334 }
335
pca954x_deselect_mux(struct i2c_mux_core * muxc,u32 chan)336 static int pca954x_deselect_mux(struct i2c_mux_core *muxc, u32 chan)
337 {
338 struct pca954x *data = i2c_mux_priv(muxc);
339 struct i2c_client *client = data->client;
340 s32 idle_state;
341
342 idle_state = READ_ONCE(data->idle_state);
343 if (idle_state >= 0)
344 /* Set the mux back to a predetermined channel */
345 return pca954x_select_chan(muxc, idle_state);
346
347 if (idle_state == MUX_IDLE_DISCONNECT) {
348 /* Deselect active channel */
349 data->last_chan = 0;
350 return pca954x_reg_write(muxc->parent, client,
351 data->last_chan);
352 }
353
354 /* otherwise leave as-is */
355
356 return 0;
357 }
358
idle_state_show(struct device * dev,struct device_attribute * attr,char * buf)359 static ssize_t idle_state_show(struct device *dev,
360 struct device_attribute *attr,
361 char *buf)
362 {
363 struct i2c_client *client = to_i2c_client(dev);
364 struct i2c_mux_core *muxc = i2c_get_clientdata(client);
365 struct pca954x *data = i2c_mux_priv(muxc);
366
367 return sprintf(buf, "%d\n", READ_ONCE(data->idle_state));
368 }
369
idle_state_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)370 static ssize_t idle_state_store(struct device *dev,
371 struct device_attribute *attr,
372 const char *buf, size_t count)
373 {
374 struct i2c_client *client = to_i2c_client(dev);
375 struct i2c_mux_core *muxc = i2c_get_clientdata(client);
376 struct pca954x *data = i2c_mux_priv(muxc);
377 int val;
378 int ret;
379
380 ret = kstrtoint(buf, 0, &val);
381 if (ret < 0)
382 return ret;
383
384 if (val != MUX_IDLE_AS_IS && val != MUX_IDLE_DISCONNECT &&
385 (val < 0 || val >= data->chip->nchans))
386 return -EINVAL;
387
388 i2c_lock_bus(muxc->parent, I2C_LOCK_SEGMENT);
389
390 WRITE_ONCE(data->idle_state, val);
391 /*
392 * Set the mux into a state consistent with the new
393 * idle_state.
394 */
395 if (data->last_chan || val != MUX_IDLE_DISCONNECT)
396 ret = pca954x_deselect_mux(muxc, 0);
397
398 i2c_unlock_bus(muxc->parent, I2C_LOCK_SEGMENT);
399
400 return ret < 0 ? ret : count;
401 }
402
403 static DEVICE_ATTR_RW(idle_state);
404
pca954x_irq_handler(int irq,void * dev_id)405 static irqreturn_t pca954x_irq_handler(int irq, void *dev_id)
406 {
407 struct pca954x *data = dev_id;
408 unsigned long pending;
409 int ret, i;
410
411 ret = i2c_smbus_read_byte(data->client);
412 if (ret < 0)
413 return IRQ_NONE;
414
415 pending = (ret >> PCA954X_IRQ_OFFSET) & (BIT(data->chip->nchans) - 1);
416 for_each_set_bit(i, &pending, data->chip->nchans)
417 handle_nested_irq(irq_find_mapping(data->irq, i));
418
419 return IRQ_RETVAL(pending);
420 }
421
pca954x_irq_set_type(struct irq_data * idata,unsigned int type)422 static int pca954x_irq_set_type(struct irq_data *idata, unsigned int type)
423 {
424 if ((type & IRQ_TYPE_SENSE_MASK) != IRQ_TYPE_LEVEL_LOW)
425 return -EINVAL;
426 return 0;
427 }
428
429 static struct irq_chip pca954x_irq_chip = {
430 .name = "i2c-mux-pca954x",
431 .irq_set_type = pca954x_irq_set_type,
432 };
433
pca954x_irq_setup(struct i2c_mux_core * muxc)434 static int pca954x_irq_setup(struct i2c_mux_core *muxc)
435 {
436 struct pca954x *data = i2c_mux_priv(muxc);
437 struct i2c_client *client = data->client;
438 int c, irq;
439
440 if (!data->chip->has_irq || client->irq <= 0)
441 return 0;
442
443 raw_spin_lock_init(&data->lock);
444
445 data->irq = irq_domain_create_linear(dev_fwnode(&client->dev), data->chip->nchans,
446 &irq_domain_simple_ops, data);
447 if (!data->irq)
448 return -ENODEV;
449
450 for (c = 0; c < data->chip->nchans; c++) {
451 irq = irq_create_mapping(data->irq, c);
452 if (!irq) {
453 dev_err(&client->dev, "failed irq create map\n");
454 return -EINVAL;
455 }
456 irq_set_chip_data(irq, data);
457 irq_set_chip_and_handler(irq, &pca954x_irq_chip,
458 handle_simple_irq);
459 }
460
461 return 0;
462 }
463
pca954x_cleanup(struct i2c_mux_core * muxc)464 static void pca954x_cleanup(struct i2c_mux_core *muxc)
465 {
466 struct pca954x *data = i2c_mux_priv(muxc);
467 int c, irq;
468
469 regulator_disable(data->supply);
470
471 if (data->irq) {
472 for (c = 0; c < data->chip->nchans; c++) {
473 irq = irq_find_mapping(data->irq, c);
474 irq_dispose_mapping(irq);
475 }
476 irq_domain_remove(data->irq);
477 }
478 i2c_mux_del_adapters(muxc);
479 }
480
pca954x_init(struct i2c_client * client,struct pca954x * data)481 static int pca954x_init(struct i2c_client *client, struct pca954x *data)
482 {
483 int ret;
484
485 if (data->idle_state >= 0)
486 data->last_chan = pca954x_regval(data, data->idle_state);
487 else
488 data->last_chan = 0; /* Disconnect multiplexer */
489
490 if (device_is_compatible(&client->dev, "maxim,max7357")) {
491 if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) {
492 u8 conf = MAX7357_POR_DEFAULT_CONF;
493 /*
494 * The interrupt signal is shared with the reset pin. Release the
495 * interrupt after 1.6 seconds to allow using the pin as reset.
496 */
497 conf |= MAX7357_CONF_RELEASE_INT;
498
499 if (device_property_read_bool(&client->dev, "maxim,isolate-stuck-channel"))
500 conf |= MAX7357_CONF_DISCON_SINGLE_CHAN;
501 if (device_property_read_bool(&client->dev,
502 "maxim,send-flush-out-sequence"))
503 conf |= MAX7357_CONF_FLUSH_OUT;
504 if (device_property_read_bool(&client->dev,
505 "maxim,preconnection-wiggle-test-enable"))
506 conf |= MAX7357_CONF_PRECONNECT_TEST;
507
508 ret = i2c_smbus_write_byte_data(client, data->last_chan, conf);
509 } else {
510 dev_warn(&client->dev, "Write byte data not supported."
511 "Cannot enable enhanced mode features\n");
512 ret = i2c_smbus_write_byte(client, data->last_chan);
513 }
514 } else {
515 ret = i2c_smbus_write_byte(client, data->last_chan);
516 }
517
518 if (ret < 0)
519 data->last_chan = 0;
520
521 return ret;
522 }
523
pca954x_get_reset(struct device * dev,struct pca954x * data)524 static int pca954x_get_reset(struct device *dev, struct pca954x *data)
525 {
526 data->reset_cont = devm_reset_control_get_optional_shared(dev, NULL);
527 if (IS_ERR(data->reset_cont))
528 return dev_err_probe(dev, PTR_ERR(data->reset_cont),
529 "Failed to get reset\n");
530 else if (data->reset_cont)
531 return 0;
532
533 /*
534 * fallback to legacy reset-gpios
535 */
536 data->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
537 if (IS_ERR(data->reset_gpio)) {
538 return dev_err_probe(dev, PTR_ERR(data->reset_gpio),
539 "Failed to get reset gpio");
540 }
541
542 return 0;
543 }
544
pca954x_reset_deassert(struct pca954x * data)545 static void pca954x_reset_deassert(struct pca954x *data)
546 {
547 if (data->reset_cont)
548 reset_control_deassert(data->reset_cont);
549 else
550 gpiod_set_value_cansleep(data->reset_gpio, 0);
551 }
552
553 /*
554 * I2C init/probing/exit functions
555 */
pca954x_probe(struct i2c_client * client)556 static int pca954x_probe(struct i2c_client *client)
557 {
558 const struct i2c_device_id *id = i2c_client_get_device_id(client);
559 struct i2c_adapter *adap = client->adapter;
560 struct device *dev = &client->dev;
561 struct i2c_mux_core *muxc;
562 struct pca954x *data;
563 int num;
564 int ret;
565
566 if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE))
567 return -ENODEV;
568
569 muxc = i2c_mux_alloc(adap, dev, PCA954X_MAX_NCHANS, sizeof(*data), 0,
570 pca954x_select_chan, pca954x_deselect_mux);
571 if (!muxc)
572 return -ENOMEM;
573 data = i2c_mux_priv(muxc);
574
575 i2c_set_clientdata(client, muxc);
576 data->client = client;
577
578 data->supply = devm_regulator_get(dev, "vdd");
579 if (IS_ERR(data->supply))
580 return dev_err_probe(dev, PTR_ERR(data->supply),
581 "Failed to request regulator\n");
582
583 ret = regulator_enable(data->supply);
584 if (ret)
585 return dev_err_probe(dev, ret,
586 "Failed to enable vdd supply\n");
587
588 ret = pca954x_get_reset(dev, data);
589 if (ret)
590 goto fail_cleanup;
591
592 if (data->reset_cont || data->reset_gpio) {
593 udelay(1);
594 pca954x_reset_deassert(data);
595 /* Give the chip some time to recover. */
596 udelay(1);
597 }
598
599 data->chip = device_get_match_data(dev);
600 if (!data->chip)
601 data->chip = &chips[id->driver_data];
602
603 if (data->chip->id.manufacturer_id != I2C_DEVICE_ID_NONE) {
604 struct i2c_device_identity id;
605
606 ret = i2c_get_device_id(client, &id);
607 if (ret && ret != -EOPNOTSUPP)
608 goto fail_cleanup;
609
610 if (!ret &&
611 (id.manufacturer_id != data->chip->id.manufacturer_id ||
612 id.part_id != data->chip->id.part_id)) {
613 dev_warn(dev, "unexpected device id %03x-%03x-%x\n",
614 id.manufacturer_id, id.part_id,
615 id.die_revision);
616 ret = -ENODEV;
617 goto fail_cleanup;
618 }
619 }
620
621 data->idle_state = MUX_IDLE_AS_IS;
622 if (device_property_read_u32(dev, "idle-state", &data->idle_state)) {
623 if (device_property_read_bool(dev, "i2c-mux-idle-disconnect"))
624 data->idle_state = MUX_IDLE_DISCONNECT;
625 }
626
627 /*
628 * Write the mux register at addr to verify
629 * that the mux is in fact present. This also
630 * initializes the mux to a channel
631 * or disconnected state.
632 */
633 ret = pca954x_init(client, data);
634 if (ret < 0) {
635 dev_warn(dev, "probe failed\n");
636 ret = -ENODEV;
637 goto fail_cleanup;
638 }
639
640 ret = pca954x_irq_setup(muxc);
641 if (ret)
642 goto fail_cleanup;
643
644 /* Now create an adapter for each channel */
645 for (num = 0; num < data->chip->nchans; num++) {
646 ret = i2c_mux_add_adapter(muxc, 0, num);
647 if (ret)
648 goto fail_cleanup;
649 }
650
651 if (data->irq) {
652 ret = devm_request_threaded_irq(dev, data->client->irq,
653 NULL, pca954x_irq_handler,
654 IRQF_ONESHOT | IRQF_SHARED,
655 "pca954x", data);
656 if (ret)
657 goto fail_cleanup;
658 }
659
660 /*
661 * The attr probably isn't going to be needed in most cases,
662 * so don't fail completely on error.
663 */
664 device_create_file(dev, &dev_attr_idle_state);
665
666 dev_info(dev, "registered %d multiplexed busses for I2C %s %s\n",
667 num, data->chip->muxtype == pca954x_ismux
668 ? "mux" : "switch", client->name);
669
670 return 0;
671
672 fail_cleanup:
673 pca954x_cleanup(muxc);
674 return ret;
675 }
676
pca954x_remove(struct i2c_client * client)677 static void pca954x_remove(struct i2c_client *client)
678 {
679 struct i2c_mux_core *muxc = i2c_get_clientdata(client);
680
681 device_remove_file(&client->dev, &dev_attr_idle_state);
682
683 pca954x_cleanup(muxc);
684 }
685
pca954x_resume(struct device * dev)686 static int pca954x_resume(struct device *dev)
687 {
688 struct i2c_client *client = to_i2c_client(dev);
689 struct i2c_mux_core *muxc = i2c_get_clientdata(client);
690 struct pca954x *data = i2c_mux_priv(muxc);
691 int ret;
692
693 ret = pca954x_init(client, data);
694 if (ret < 0)
695 dev_err(&client->dev, "failed to verify mux presence\n");
696
697 return ret;
698 }
699
700 static DEFINE_SIMPLE_DEV_PM_OPS(pca954x_pm, NULL, pca954x_resume);
701
702 static struct i2c_driver pca954x_driver = {
703 .driver = {
704 .name = "pca954x",
705 .pm = pm_sleep_ptr(&pca954x_pm),
706 .of_match_table = pca954x_of_match,
707 },
708 .probe = pca954x_probe,
709 .remove = pca954x_remove,
710 .id_table = pca954x_id,
711 };
712
713 module_i2c_driver(pca954x_driver);
714
715 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
716 MODULE_DESCRIPTION("PCA954x I2C mux/switch driver");
717 MODULE_LICENSE("GPL v2");
718