xref: /openbmc/linux/drivers/mfd/wm8994-core.c (revision 9cfc5c90)
1 /*
2  * wm8994-core.c  --  Device access for Wolfson WM8994
3  *
4  * Copyright 2009 Wolfson Microelectronics PLC.
5  *
6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7  *
8  *  This program is free software; you can redistribute  it and/or modify it
9  *  under  the terms of  the GNU General  Public License as published by the
10  *  Free Software Foundation;  either version 2 of the  License, or (at your
11  *  option) any later version.
12  *
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/i2c.h>
19 #include <linux/err.h>
20 #include <linux/delay.h>
21 #include <linux/mfd/core.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/of_gpio.h>
25 #include <linux/pm_runtime.h>
26 #include <linux/regmap.h>
27 #include <linux/regulator/consumer.h>
28 #include <linux/regulator/machine.h>
29 
30 #include <linux/mfd/wm8994/core.h>
31 #include <linux/mfd/wm8994/pdata.h>
32 #include <linux/mfd/wm8994/registers.h>
33 
34 #include "wm8994.h"
35 
36 static const struct mfd_cell wm8994_regulator_devs[] = {
37 	{
38 		.name = "wm8994-ldo",
39 		.id = 0,
40 		.pm_runtime_no_callbacks = true,
41 	},
42 	{
43 		.name = "wm8994-ldo",
44 		.id = 1,
45 		.pm_runtime_no_callbacks = true,
46 	},
47 };
48 
49 static struct resource wm8994_codec_resources[] = {
50 	{
51 		.start = WM8994_IRQ_TEMP_SHUT,
52 		.end   = WM8994_IRQ_TEMP_WARN,
53 		.flags = IORESOURCE_IRQ,
54 	},
55 };
56 
57 static struct resource wm8994_gpio_resources[] = {
58 	{
59 		.start = WM8994_IRQ_GPIO(1),
60 		.end   = WM8994_IRQ_GPIO(11),
61 		.flags = IORESOURCE_IRQ,
62 	},
63 };
64 
65 static const struct mfd_cell wm8994_devs[] = {
66 	{
67 		.name = "wm8994-codec",
68 		.num_resources = ARRAY_SIZE(wm8994_codec_resources),
69 		.resources = wm8994_codec_resources,
70 	},
71 
72 	{
73 		.name = "wm8994-gpio",
74 		.num_resources = ARRAY_SIZE(wm8994_gpio_resources),
75 		.resources = wm8994_gpio_resources,
76 		.pm_runtime_no_callbacks = true,
77 	},
78 };
79 
80 /*
81  * Supplies for the main bulk of CODEC; the LDO supplies are ignored
82  * and should be handled via the standard regulator API supply
83  * management.
84  */
85 static const char *wm1811_main_supplies[] = {
86 	"DBVDD1",
87 	"DBVDD2",
88 	"DBVDD3",
89 	"DCVDD",
90 	"AVDD1",
91 	"AVDD2",
92 	"CPVDD",
93 	"SPKVDD1",
94 	"SPKVDD2",
95 };
96 
97 static const char *wm8994_main_supplies[] = {
98 	"DBVDD",
99 	"DCVDD",
100 	"AVDD1",
101 	"AVDD2",
102 	"CPVDD",
103 	"SPKVDD1",
104 	"SPKVDD2",
105 };
106 
107 static const char *wm8958_main_supplies[] = {
108 	"DBVDD1",
109 	"DBVDD2",
110 	"DBVDD3",
111 	"DCVDD",
112 	"AVDD1",
113 	"AVDD2",
114 	"CPVDD",
115 	"SPKVDD1",
116 	"SPKVDD2",
117 };
118 
119 #ifdef CONFIG_PM
120 static int wm8994_suspend(struct device *dev)
121 {
122 	struct wm8994 *wm8994 = dev_get_drvdata(dev);
123 	int ret;
124 
125 	/* Don't actually go through with the suspend if the CODEC is
126 	 * still active for accessory detect. */
127 	switch (wm8994->type) {
128 	case WM8958:
129 	case WM1811:
130 		ret = wm8994_reg_read(wm8994, WM8958_MIC_DETECT_1);
131 		if (ret < 0) {
132 			dev_err(dev, "Failed to read power status: %d\n", ret);
133 		} else if (ret & WM8958_MICD_ENA) {
134 			dev_dbg(dev, "CODEC still active, ignoring suspend\n");
135 			return 0;
136 		}
137 		break;
138 	default:
139 		break;
140 	}
141 
142 	/* Disable LDO pulldowns while the device is suspended if we
143 	 * don't know that something will be driving them. */
144 	if (!wm8994->ldo_ena_always_driven)
145 		wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
146 				WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
147 				WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD);
148 
149 	/* Explicitly put the device into reset in case regulators
150 	 * don't get disabled in order to ensure consistent restart.
151 	 */
152 	wm8994_reg_write(wm8994, WM8994_SOFTWARE_RESET,
153 			 wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET));
154 
155 	regcache_mark_dirty(wm8994->regmap);
156 
157 	/* Restore GPIO registers to prevent problems with mismatched
158 	 * pin configurations.
159 	 */
160 	ret = regcache_sync_region(wm8994->regmap, WM8994_GPIO_1,
161 				   WM8994_GPIO_11);
162 	if (ret != 0)
163 		dev_err(dev, "Failed to restore GPIO registers: %d\n", ret);
164 
165 	/* In case one of the GPIOs is used as a wake input. */
166 	ret = regcache_sync_region(wm8994->regmap,
167 				   WM8994_INTERRUPT_STATUS_1_MASK,
168 				   WM8994_INTERRUPT_STATUS_1_MASK);
169 	if (ret != 0)
170 		dev_err(dev, "Failed to restore interrupt mask: %d\n", ret);
171 
172 	regcache_cache_only(wm8994->regmap, true);
173 	wm8994->suspended = true;
174 
175 	ret = regulator_bulk_disable(wm8994->num_supplies,
176 				     wm8994->supplies);
177 	if (ret != 0) {
178 		dev_err(dev, "Failed to disable supplies: %d\n", ret);
179 		return ret;
180 	}
181 
182 	return 0;
183 }
184 
185 static int wm8994_resume(struct device *dev)
186 {
187 	struct wm8994 *wm8994 = dev_get_drvdata(dev);
188 	int ret;
189 
190 	/* We may have lied to the PM core about suspending */
191 	if (!wm8994->suspended)
192 		return 0;
193 
194 	ret = regulator_bulk_enable(wm8994->num_supplies,
195 				    wm8994->supplies);
196 	if (ret != 0) {
197 		dev_err(dev, "Failed to enable supplies: %d\n", ret);
198 		return ret;
199 	}
200 
201 	regcache_cache_only(wm8994->regmap, false);
202 	ret = regcache_sync(wm8994->regmap);
203 	if (ret != 0) {
204 		dev_err(dev, "Failed to restore register map: %d\n", ret);
205 		goto err_enable;
206 	}
207 
208 	/* Disable LDO pulldowns while the device is active */
209 	wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
210 			WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
211 			0);
212 
213 	wm8994->suspended = false;
214 
215 	return 0;
216 
217 err_enable:
218 	regulator_bulk_disable(wm8994->num_supplies, wm8994->supplies);
219 
220 	return ret;
221 }
222 #endif
223 
224 #ifdef CONFIG_REGULATOR
225 static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
226 {
227 	struct wm8994_ldo_pdata *ldo_pdata;
228 
229 	if (!pdata)
230 		return 0;
231 
232 	ldo_pdata = &pdata->ldo[ldo];
233 
234 	if (!ldo_pdata->init_data)
235 		return 0;
236 
237 	return ldo_pdata->init_data->num_consumer_supplies != 0;
238 }
239 #else
240 static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
241 {
242 	return 0;
243 }
244 #endif
245 
246 static const struct reg_sequence wm8994_revc_patch[] = {
247 	{ 0x102, 0x3 },
248 	{ 0x56, 0x3 },
249 	{ 0x817, 0x0 },
250 	{ 0x102, 0x0 },
251 };
252 
253 static const struct reg_sequence wm8958_reva_patch[] = {
254 	{ 0x102, 0x3 },
255 	{ 0xcb, 0x81 },
256 	{ 0x817, 0x0 },
257 	{ 0x102, 0x0 },
258 };
259 
260 static const struct reg_sequence wm1811_reva_patch[] = {
261 	{ 0x102, 0x3 },
262 	{ 0x56, 0xc07 },
263 	{ 0x5d, 0x7e },
264 	{ 0x5e, 0x0 },
265 	{ 0x102, 0x0 },
266 };
267 
268 #ifdef CONFIG_OF
269 static int wm8994_set_pdata_from_of(struct wm8994 *wm8994)
270 {
271 	struct device_node *np = wm8994->dev->of_node;
272 	struct wm8994_pdata *pdata = &wm8994->pdata;
273 	int i;
274 
275 	if (!np)
276 		return 0;
277 
278 	if (of_property_read_u32_array(np, "wlf,gpio-cfg", pdata->gpio_defaults,
279 				       ARRAY_SIZE(pdata->gpio_defaults)) >= 0) {
280 		for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) {
281 			if (wm8994->pdata.gpio_defaults[i] == 0)
282 				pdata->gpio_defaults[i]
283 					= WM8994_CONFIGURE_GPIO;
284 		}
285 	}
286 
287 	of_property_read_u32_array(np, "wlf,micbias-cfg", pdata->micbias,
288 				   ARRAY_SIZE(pdata->micbias));
289 
290 	pdata->lineout1_diff = true;
291 	pdata->lineout2_diff = true;
292 	if (of_find_property(np, "wlf,lineout1-se", NULL))
293 		pdata->lineout1_diff = false;
294 	if (of_find_property(np, "wlf,lineout2-se", NULL))
295 		pdata->lineout2_diff = false;
296 
297 	if (of_find_property(np, "wlf,lineout1-feedback", NULL))
298 		pdata->lineout1fb = true;
299 	if (of_find_property(np, "wlf,lineout2-feedback", NULL))
300 		pdata->lineout2fb = true;
301 
302 	if (of_find_property(np, "wlf,ldoena-always-driven", NULL))
303 		pdata->lineout2fb = true;
304 
305 	pdata->ldo[0].enable = of_get_named_gpio(np, "wlf,ldo1ena", 0);
306 	if (pdata->ldo[0].enable < 0)
307 		pdata->ldo[0].enable = 0;
308 
309 	pdata->ldo[1].enable = of_get_named_gpio(np, "wlf,ldo2ena", 0);
310 	if (pdata->ldo[1].enable < 0)
311 		pdata->ldo[1].enable = 0;
312 
313 	return 0;
314 }
315 #else
316 static int wm8994_set_pdata_from_of(struct wm8994 *wm8994)
317 {
318 	return 0;
319 }
320 #endif
321 
322 /*
323  * Instantiate the generic non-control parts of the device.
324  */
325 static int wm8994_device_init(struct wm8994 *wm8994, int irq)
326 {
327 	struct wm8994_pdata *pdata;
328 	struct regmap_config *regmap_config;
329 	const struct reg_sequence *regmap_patch = NULL;
330 	const char *devname;
331 	int ret, i, patch_regs = 0;
332 	int pulls = 0;
333 
334 	if (dev_get_platdata(wm8994->dev)) {
335 		pdata = dev_get_platdata(wm8994->dev);
336 		wm8994->pdata = *pdata;
337 	}
338 	pdata = &wm8994->pdata;
339 
340 	ret = wm8994_set_pdata_from_of(wm8994);
341 	if (ret != 0)
342 		return ret;
343 
344 	dev_set_drvdata(wm8994->dev, wm8994);
345 
346 	/* Add the on-chip regulators first for bootstrapping */
347 	ret = mfd_add_devices(wm8994->dev, 0,
348 			      wm8994_regulator_devs,
349 			      ARRAY_SIZE(wm8994_regulator_devs),
350 			      NULL, 0, NULL);
351 	if (ret != 0) {
352 		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
353 		goto err;
354 	}
355 
356 	switch (wm8994->type) {
357 	case WM1811:
358 		wm8994->num_supplies = ARRAY_SIZE(wm1811_main_supplies);
359 		break;
360 	case WM8994:
361 		wm8994->num_supplies = ARRAY_SIZE(wm8994_main_supplies);
362 		break;
363 	case WM8958:
364 		wm8994->num_supplies = ARRAY_SIZE(wm8958_main_supplies);
365 		break;
366 	default:
367 		BUG();
368 		goto err;
369 	}
370 
371 	wm8994->supplies = devm_kzalloc(wm8994->dev,
372 					sizeof(struct regulator_bulk_data) *
373 					wm8994->num_supplies, GFP_KERNEL);
374 	if (!wm8994->supplies) {
375 		ret = -ENOMEM;
376 		goto err;
377 	}
378 
379 	switch (wm8994->type) {
380 	case WM1811:
381 		for (i = 0; i < ARRAY_SIZE(wm1811_main_supplies); i++)
382 			wm8994->supplies[i].supply = wm1811_main_supplies[i];
383 		break;
384 	case WM8994:
385 		for (i = 0; i < ARRAY_SIZE(wm8994_main_supplies); i++)
386 			wm8994->supplies[i].supply = wm8994_main_supplies[i];
387 		break;
388 	case WM8958:
389 		for (i = 0; i < ARRAY_SIZE(wm8958_main_supplies); i++)
390 			wm8994->supplies[i].supply = wm8958_main_supplies[i];
391 		break;
392 	default:
393 		BUG();
394 		goto err;
395 	}
396 
397 	ret = devm_regulator_bulk_get(wm8994->dev, wm8994->num_supplies,
398 				 wm8994->supplies);
399 	if (ret != 0) {
400 		dev_err(wm8994->dev, "Failed to get supplies: %d\n", ret);
401 		goto err;
402 	}
403 
404 	ret = regulator_bulk_enable(wm8994->num_supplies,
405 				    wm8994->supplies);
406 	if (ret != 0) {
407 		dev_err(wm8994->dev, "Failed to enable supplies: %d\n", ret);
408 		goto err;
409 	}
410 
411 	ret = wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET);
412 	if (ret < 0) {
413 		dev_err(wm8994->dev, "Failed to read ID register\n");
414 		goto err_enable;
415 	}
416 	switch (ret) {
417 	case 0x1811:
418 		devname = "WM1811";
419 		if (wm8994->type != WM1811)
420 			dev_warn(wm8994->dev, "Device registered as type %d\n",
421 				 wm8994->type);
422 		wm8994->type = WM1811;
423 		break;
424 	case 0x8994:
425 		devname = "WM8994";
426 		if (wm8994->type != WM8994)
427 			dev_warn(wm8994->dev, "Device registered as type %d\n",
428 				 wm8994->type);
429 		wm8994->type = WM8994;
430 		break;
431 	case 0x8958:
432 		devname = "WM8958";
433 		if (wm8994->type != WM8958)
434 			dev_warn(wm8994->dev, "Device registered as type %d\n",
435 				 wm8994->type);
436 		wm8994->type = WM8958;
437 		break;
438 	default:
439 		dev_err(wm8994->dev, "Device is not a WM8994, ID is %x\n",
440 			ret);
441 		ret = -EINVAL;
442 		goto err_enable;
443 	}
444 
445 	ret = wm8994_reg_read(wm8994, WM8994_CHIP_REVISION);
446 	if (ret < 0) {
447 		dev_err(wm8994->dev, "Failed to read revision register: %d\n",
448 			ret);
449 		goto err_enable;
450 	}
451 	wm8994->revision = ret & WM8994_CHIP_REV_MASK;
452 	wm8994->cust_id = (ret & WM8994_CUST_ID_MASK) >> WM8994_CUST_ID_SHIFT;
453 
454 	switch (wm8994->type) {
455 	case WM8994:
456 		switch (wm8994->revision) {
457 		case 0:
458 		case 1:
459 			dev_warn(wm8994->dev,
460 				 "revision %c not fully supported\n",
461 				 'A' + wm8994->revision);
462 			break;
463 		case 2:
464 		case 3:
465 		default:
466 			regmap_patch = wm8994_revc_patch;
467 			patch_regs = ARRAY_SIZE(wm8994_revc_patch);
468 			break;
469 		}
470 		break;
471 
472 	case WM8958:
473 		switch (wm8994->revision) {
474 		case 0:
475 			regmap_patch = wm8958_reva_patch;
476 			patch_regs = ARRAY_SIZE(wm8958_reva_patch);
477 			break;
478 		default:
479 			break;
480 		}
481 		break;
482 
483 	case WM1811:
484 		/* Revision C did not change the relevant layer */
485 		if (wm8994->revision > 1)
486 			wm8994->revision++;
487 
488 		regmap_patch = wm1811_reva_patch;
489 		patch_regs = ARRAY_SIZE(wm1811_reva_patch);
490 		break;
491 
492 	default:
493 		break;
494 	}
495 
496 	dev_info(wm8994->dev, "%s revision %c CUST_ID %02x\n", devname,
497 		 'A' + wm8994->revision, wm8994->cust_id);
498 
499 	switch (wm8994->type) {
500 	case WM1811:
501 		regmap_config = &wm1811_regmap_config;
502 		break;
503 	case WM8994:
504 		regmap_config = &wm8994_regmap_config;
505 		break;
506 	case WM8958:
507 		regmap_config = &wm8958_regmap_config;
508 		break;
509 	default:
510 		dev_err(wm8994->dev, "Unknown device type %d\n", wm8994->type);
511 		return -EINVAL;
512 	}
513 
514 	ret = regmap_reinit_cache(wm8994->regmap, regmap_config);
515 	if (ret != 0) {
516 		dev_err(wm8994->dev, "Failed to reinit register cache: %d\n",
517 			ret);
518 		return ret;
519 	}
520 
521 	/* Explicitly put the device into reset in case regulators
522 	 * don't get disabled in order to ensure we know the device
523 	 * state.
524 	 */
525 	ret = wm8994_reg_write(wm8994, WM8994_SOFTWARE_RESET,
526 			       wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET));
527 	if (ret != 0) {
528 		dev_err(wm8994->dev, "Failed to reset device: %d\n", ret);
529 		return ret;
530 	}
531 
532 	if (regmap_patch) {
533 		ret = regmap_register_patch(wm8994->regmap, regmap_patch,
534 					    patch_regs);
535 		if (ret != 0) {
536 			dev_err(wm8994->dev, "Failed to register patch: %d\n",
537 				ret);
538 			goto err;
539 		}
540 	}
541 
542 	wm8994->irq_base = pdata->irq_base;
543 	wm8994->gpio_base = pdata->gpio_base;
544 
545 	/* GPIO configuration is only applied if it's non-zero */
546 	for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) {
547 		if (pdata->gpio_defaults[i]) {
548 			wm8994_set_bits(wm8994, WM8994_GPIO_1 + i,
549 					0xffff, pdata->gpio_defaults[i]);
550 		}
551 	}
552 
553 	wm8994->ldo_ena_always_driven = pdata->ldo_ena_always_driven;
554 
555 	if (pdata->spkmode_pu)
556 		pulls |= WM8994_SPKMODE_PU;
557 
558 	/* Disable unneeded pulls */
559 	wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
560 			WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD |
561 			WM8994_SPKMODE_PU | WM8994_CSNADDR_PD,
562 			pulls);
563 
564 	/* In some system designs where the regulators are not in use,
565 	 * we can achieve a small reduction in leakage currents by
566 	 * floating LDO outputs.  This bit makes no difference if the
567 	 * LDOs are enabled, it only affects cases where the LDOs were
568 	 * in operation and are then disabled.
569 	 */
570 	for (i = 0; i < WM8994_NUM_LDO_REGS; i++) {
571 		if (wm8994_ldo_in_use(pdata, i))
572 			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
573 					WM8994_LDO1_DISCH, WM8994_LDO1_DISCH);
574 		else
575 			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
576 					WM8994_LDO1_DISCH, 0);
577 	}
578 
579 	wm8994_irq_init(wm8994);
580 
581 	ret = mfd_add_devices(wm8994->dev, -1,
582 			      wm8994_devs, ARRAY_SIZE(wm8994_devs),
583 			      NULL, 0, NULL);
584 	if (ret != 0) {
585 		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
586 		goto err_irq;
587 	}
588 
589 	pm_runtime_enable(wm8994->dev);
590 	pm_runtime_idle(wm8994->dev);
591 
592 	return 0;
593 
594 err_irq:
595 	wm8994_irq_exit(wm8994);
596 err_enable:
597 	regulator_bulk_disable(wm8994->num_supplies,
598 			       wm8994->supplies);
599 err:
600 	mfd_remove_devices(wm8994->dev);
601 	return ret;
602 }
603 
604 static void wm8994_device_exit(struct wm8994 *wm8994)
605 {
606 	pm_runtime_disable(wm8994->dev);
607 	mfd_remove_devices(wm8994->dev);
608 	wm8994_irq_exit(wm8994);
609 	regulator_bulk_disable(wm8994->num_supplies,
610 			       wm8994->supplies);
611 }
612 
613 static const struct of_device_id wm8994_of_match[] = {
614 	{ .compatible = "wlf,wm1811", .data = (void *)WM1811 },
615 	{ .compatible = "wlf,wm8994", .data = (void *)WM8994 },
616 	{ .compatible = "wlf,wm8958", .data = (void *)WM8958 },
617 	{ }
618 };
619 MODULE_DEVICE_TABLE(of, wm8994_of_match);
620 
621 static int wm8994_i2c_probe(struct i2c_client *i2c,
622 				      const struct i2c_device_id *id)
623 {
624 	const struct of_device_id *of_id;
625 	struct wm8994 *wm8994;
626 	int ret;
627 
628 	wm8994 = devm_kzalloc(&i2c->dev, sizeof(struct wm8994), GFP_KERNEL);
629 	if (wm8994 == NULL)
630 		return -ENOMEM;
631 
632 	i2c_set_clientdata(i2c, wm8994);
633 	wm8994->dev = &i2c->dev;
634 	wm8994->irq = i2c->irq;
635 
636 	if (i2c->dev.of_node) {
637 		of_id = of_match_device(wm8994_of_match, &i2c->dev);
638 		if (of_id)
639 			wm8994->type = (enum wm8994_type)of_id->data;
640 	} else {
641 		wm8994->type = id->driver_data;
642 	}
643 
644 	wm8994->regmap = devm_regmap_init_i2c(i2c, &wm8994_base_regmap_config);
645 	if (IS_ERR(wm8994->regmap)) {
646 		ret = PTR_ERR(wm8994->regmap);
647 		dev_err(wm8994->dev, "Failed to allocate register map: %d\n",
648 			ret);
649 		return ret;
650 	}
651 
652 	return wm8994_device_init(wm8994, i2c->irq);
653 }
654 
655 static int wm8994_i2c_remove(struct i2c_client *i2c)
656 {
657 	struct wm8994 *wm8994 = i2c_get_clientdata(i2c);
658 
659 	wm8994_device_exit(wm8994);
660 
661 	return 0;
662 }
663 
664 static const struct i2c_device_id wm8994_i2c_id[] = {
665 	{ "wm1811", WM1811 },
666 	{ "wm1811a", WM1811 },
667 	{ "wm8994", WM8994 },
668 	{ "wm8958", WM8958 },
669 	{ }
670 };
671 MODULE_DEVICE_TABLE(i2c, wm8994_i2c_id);
672 
673 static const struct dev_pm_ops wm8994_pm_ops = {
674 	SET_RUNTIME_PM_OPS(wm8994_suspend, wm8994_resume, NULL)
675 };
676 
677 static struct i2c_driver wm8994_i2c_driver = {
678 	.driver = {
679 		.name = "wm8994",
680 		.pm = &wm8994_pm_ops,
681 		.of_match_table = of_match_ptr(wm8994_of_match),
682 	},
683 	.probe = wm8994_i2c_probe,
684 	.remove = wm8994_i2c_remove,
685 	.id_table = wm8994_i2c_id,
686 };
687 
688 module_i2c_driver(wm8994_i2c_driver);
689 
690 MODULE_DESCRIPTION("Core support for the WM8994 audio CODEC");
691 MODULE_LICENSE("GPL");
692 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
693