wm8994-core.c revision 881de67046f424fc3a6e05b1c681c12afd94e802
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/delay.h>
20#include <linux/mfd/core.h>
21#include <linux/pm_runtime.h>
22#include <linux/regulator/consumer.h>
23#include <linux/regulator/machine.h>
24
25#include <linux/mfd/wm8994/core.h>
26#include <linux/mfd/wm8994/pdata.h>
27#include <linux/mfd/wm8994/registers.h>
28
29static int wm8994_read(struct wm8994 *wm8994, unsigned short reg,
30		       int bytes, void *dest)
31{
32	int ret, i;
33	u16 *buf = dest;
34
35	BUG_ON(bytes % 2);
36	BUG_ON(bytes <= 0);
37
38	ret = wm8994->read_dev(wm8994, reg, bytes, dest);
39	if (ret < 0)
40		return ret;
41
42	for (i = 0; i < bytes / 2; i++) {
43		dev_vdbg(wm8994->dev, "Read %04x from R%d(0x%x)\n",
44			 be16_to_cpu(buf[i]), reg + i, reg + i);
45	}
46
47	return 0;
48}
49
50/**
51 * wm8994_reg_read: Read a single WM8994 register.
52 *
53 * @wm8994: Device to read from.
54 * @reg: Register to read.
55 */
56int wm8994_reg_read(struct wm8994 *wm8994, unsigned short reg)
57{
58	unsigned short val;
59	int ret;
60
61	mutex_lock(&wm8994->io_lock);
62
63	ret = wm8994_read(wm8994, reg, 2, &val);
64
65	mutex_unlock(&wm8994->io_lock);
66
67	if (ret < 0)
68		return ret;
69	else
70		return be16_to_cpu(val);
71}
72EXPORT_SYMBOL_GPL(wm8994_reg_read);
73
74/**
75 * wm8994_bulk_read: Read multiple WM8994 registers
76 *
77 * @wm8994: Device to read from
78 * @reg: First register
79 * @count: Number of registers
80 * @buf: Buffer to fill.  The data will be returned big endian.
81 */
82int wm8994_bulk_read(struct wm8994 *wm8994, unsigned short reg,
83		     int count, u16 *buf)
84{
85	int ret;
86
87	mutex_lock(&wm8994->io_lock);
88
89	ret = wm8994_read(wm8994, reg, count * 2, buf);
90
91	mutex_unlock(&wm8994->io_lock);
92
93	return ret;
94}
95EXPORT_SYMBOL_GPL(wm8994_bulk_read);
96
97static int wm8994_write(struct wm8994 *wm8994, unsigned short reg,
98			int bytes, const void *src)
99{
100	const u16 *buf = src;
101	int i;
102
103	BUG_ON(bytes % 2);
104	BUG_ON(bytes <= 0);
105
106	for (i = 0; i < bytes / 2; i++) {
107		dev_vdbg(wm8994->dev, "Write %04x to R%d(0x%x)\n",
108			 be16_to_cpu(buf[i]), reg + i, reg + i);
109	}
110
111	return wm8994->write_dev(wm8994, reg, bytes, src);
112}
113
114/**
115 * wm8994_reg_write: Write a single WM8994 register.
116 *
117 * @wm8994: Device to write to.
118 * @reg: Register to write to.
119 * @val: Value to write.
120 */
121int wm8994_reg_write(struct wm8994 *wm8994, unsigned short reg,
122		     unsigned short val)
123{
124	int ret;
125
126	val = cpu_to_be16(val);
127
128	mutex_lock(&wm8994->io_lock);
129
130	ret = wm8994_write(wm8994, reg, 2, &val);
131
132	mutex_unlock(&wm8994->io_lock);
133
134	return ret;
135}
136EXPORT_SYMBOL_GPL(wm8994_reg_write);
137
138/**
139 * wm8994_bulk_write: Write multiple WM8994 registers
140 *
141 * @wm8994: Device to write to
142 * @reg: First register
143 * @count: Number of registers
144 * @buf: Buffer to write from.  Data must be big-endian formatted.
145 */
146int wm8994_bulk_write(struct wm8994 *wm8994, unsigned short reg,
147		      int count, const u16 *buf)
148{
149	int ret;
150
151	mutex_lock(&wm8994->io_lock);
152
153	ret = wm8994_write(wm8994, reg, count * 2, buf);
154
155	mutex_unlock(&wm8994->io_lock);
156
157	return ret;
158}
159EXPORT_SYMBOL_GPL(wm8994_bulk_write);
160
161/**
162 * wm8994_set_bits: Set the value of a bitfield in a WM8994 register
163 *
164 * @wm8994: Device to write to.
165 * @reg: Register to write to.
166 * @mask: Mask of bits to set.
167 * @val: Value to set (unshifted)
168 */
169int wm8994_set_bits(struct wm8994 *wm8994, unsigned short reg,
170		    unsigned short mask, unsigned short val)
171{
172	int ret;
173	u16 r;
174
175	mutex_lock(&wm8994->io_lock);
176
177	ret = wm8994_read(wm8994, reg, 2, &r);
178	if (ret < 0)
179		goto out;
180
181	r = be16_to_cpu(r);
182
183	r &= ~mask;
184	r |= val;
185
186	r = cpu_to_be16(r);
187
188	ret = wm8994_write(wm8994, reg, 2, &r);
189
190out:
191	mutex_unlock(&wm8994->io_lock);
192
193	return ret;
194}
195EXPORT_SYMBOL_GPL(wm8994_set_bits);
196
197static struct mfd_cell wm8994_regulator_devs[] = {
198	{
199		.name = "wm8994-ldo",
200		.id = 1,
201		.pm_runtime_no_callbacks = true,
202	},
203	{
204		.name = "wm8994-ldo",
205		.id = 2,
206		.pm_runtime_no_callbacks = true,
207	},
208};
209
210static struct resource wm8994_codec_resources[] = {
211	{
212		.start = WM8994_IRQ_TEMP_SHUT,
213		.end   = WM8994_IRQ_TEMP_WARN,
214		.flags = IORESOURCE_IRQ,
215	},
216};
217
218static struct resource wm8994_gpio_resources[] = {
219	{
220		.start = WM8994_IRQ_GPIO(1),
221		.end   = WM8994_IRQ_GPIO(11),
222		.flags = IORESOURCE_IRQ,
223	},
224};
225
226static struct mfd_cell wm8994_devs[] = {
227	{
228		.name = "wm8994-codec",
229		.num_resources = ARRAY_SIZE(wm8994_codec_resources),
230		.resources = wm8994_codec_resources,
231	},
232
233	{
234		.name = "wm8994-gpio",
235		.num_resources = ARRAY_SIZE(wm8994_gpio_resources),
236		.resources = wm8994_gpio_resources,
237		.pm_runtime_no_callbacks = true,
238	},
239};
240
241/*
242 * Supplies for the main bulk of CODEC; the LDO supplies are ignored
243 * and should be handled via the standard regulator API supply
244 * management.
245 */
246static const char *wm8994_main_supplies[] = {
247	"DBVDD",
248	"DCVDD",
249	"AVDD1",
250	"AVDD2",
251	"CPVDD",
252	"SPKVDD1",
253	"SPKVDD2",
254};
255
256static const char *wm8958_main_supplies[] = {
257	"DBVDD1",
258	"DBVDD2",
259	"DBVDD3",
260	"DCVDD",
261	"AVDD1",
262	"AVDD2",
263	"CPVDD",
264	"SPKVDD1",
265	"SPKVDD2",
266};
267
268#ifdef CONFIG_PM
269static int wm8994_suspend(struct device *dev)
270{
271	struct wm8994 *wm8994 = dev_get_drvdata(dev);
272	int ret;
273
274	/* Don't actually go through with the suspend if the CODEC is
275	 * still active (eg, for audio passthrough from CP. */
276	ret = wm8994_reg_read(wm8994, WM8994_POWER_MANAGEMENT_1);
277	if (ret < 0) {
278		dev_err(dev, "Failed to read power status: %d\n", ret);
279	} else if (ret & WM8994_VMID_SEL_MASK) {
280		dev_dbg(dev, "CODEC still active, ignoring suspend\n");
281		return 0;
282	}
283
284	/* Disable LDO pulldowns while the device is suspended if we
285	 * don't know that something will be driving them. */
286	if (!wm8994->ldo_ena_always_driven)
287		wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
288				WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
289				WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD);
290
291	/* GPIO configuration state is saved here since we may be configuring
292	 * the GPIO alternate functions even if we're not using the gpiolib
293	 * driver for them.
294	 */
295	ret = wm8994_read(wm8994, WM8994_GPIO_1, WM8994_NUM_GPIO_REGS * 2,
296			  &wm8994->gpio_regs);
297	if (ret < 0)
298		dev_err(dev, "Failed to save GPIO registers: %d\n", ret);
299
300	/* For similar reasons we also stash the regulator states */
301	ret = wm8994_read(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
302			  &wm8994->ldo_regs);
303	if (ret < 0)
304		dev_err(dev, "Failed to save LDO registers: %d\n", ret);
305
306	/* Explicitly put the device into reset in case regulators
307	 * don't get disabled in order to ensure consistent restart.
308	 */
309	wm8994_reg_write(wm8994, WM8994_SOFTWARE_RESET, 0x8994);
310
311	wm8994->suspended = true;
312
313	ret = regulator_bulk_disable(wm8994->num_supplies,
314				     wm8994->supplies);
315	if (ret != 0) {
316		dev_err(dev, "Failed to disable supplies: %d\n", ret);
317		return ret;
318	}
319
320	return 0;
321}
322
323static int wm8994_resume(struct device *dev)
324{
325	struct wm8994 *wm8994 = dev_get_drvdata(dev);
326	int ret, i;
327
328	/* We may have lied to the PM core about suspending */
329	if (!wm8994->suspended)
330		return 0;
331
332	ret = regulator_bulk_enable(wm8994->num_supplies,
333				    wm8994->supplies);
334	if (ret != 0) {
335		dev_err(dev, "Failed to enable supplies: %d\n", ret);
336		return ret;
337	}
338
339	/* Write register at a time as we use the cache on the CPU so store
340	 * it in native endian.
341	 */
342	for (i = 0; i < ARRAY_SIZE(wm8994->irq_masks_cur); i++) {
343		ret = wm8994_reg_write(wm8994, WM8994_INTERRUPT_STATUS_1_MASK
344				       + i, wm8994->irq_masks_cur[i]);
345		if (ret < 0)
346			dev_err(dev, "Failed to restore interrupt masks: %d\n",
347				ret);
348	}
349
350	ret = wm8994_write(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
351			   &wm8994->ldo_regs);
352	if (ret < 0)
353		dev_err(dev, "Failed to restore LDO registers: %d\n", ret);
354
355	ret = wm8994_write(wm8994, WM8994_GPIO_1, WM8994_NUM_GPIO_REGS * 2,
356			   &wm8994->gpio_regs);
357	if (ret < 0)
358		dev_err(dev, "Failed to restore GPIO registers: %d\n", ret);
359
360	/* Disable LDO pulldowns while the device is active */
361	wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
362			WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
363			0);
364
365	wm8994->suspended = false;
366
367	return 0;
368}
369#endif
370
371#ifdef CONFIG_REGULATOR
372static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
373{
374	struct wm8994_ldo_pdata *ldo_pdata;
375
376	if (!pdata)
377		return 0;
378
379	ldo_pdata = &pdata->ldo[ldo];
380
381	if (!ldo_pdata->init_data)
382		return 0;
383
384	return ldo_pdata->init_data->num_consumer_supplies != 0;
385}
386#else
387static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
388{
389	return 0;
390}
391#endif
392
393/*
394 * Instantiate the generic non-control parts of the device.
395 */
396static int wm8994_device_init(struct wm8994 *wm8994, int irq)
397{
398	struct wm8994_pdata *pdata = wm8994->dev->platform_data;
399	const char *devname;
400	int ret, i;
401
402	mutex_init(&wm8994->io_lock);
403	dev_set_drvdata(wm8994->dev, wm8994);
404
405	/* Add the on-chip regulators first for bootstrapping */
406	ret = mfd_add_devices(wm8994->dev, -1,
407			      wm8994_regulator_devs,
408			      ARRAY_SIZE(wm8994_regulator_devs),
409			      NULL, 0);
410	if (ret != 0) {
411		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
412		goto err;
413	}
414
415	switch (wm8994->type) {
416	case WM8994:
417		wm8994->num_supplies = ARRAY_SIZE(wm8994_main_supplies);
418		break;
419	case WM8958:
420		wm8994->num_supplies = ARRAY_SIZE(wm8958_main_supplies);
421		break;
422	default:
423		BUG();
424		goto err;
425	}
426
427	wm8994->supplies = kzalloc(sizeof(struct regulator_bulk_data) *
428				   wm8994->num_supplies,
429				   GFP_KERNEL);
430	if (!wm8994->supplies) {
431		ret = -ENOMEM;
432		goto err;
433	}
434
435	switch (wm8994->type) {
436	case WM8994:
437		for (i = 0; i < ARRAY_SIZE(wm8994_main_supplies); i++)
438			wm8994->supplies[i].supply = wm8994_main_supplies[i];
439		break;
440	case WM8958:
441		for (i = 0; i < ARRAY_SIZE(wm8958_main_supplies); i++)
442			wm8994->supplies[i].supply = wm8958_main_supplies[i];
443		break;
444	default:
445		BUG();
446		goto err;
447	}
448
449	ret = regulator_bulk_get(wm8994->dev, wm8994->num_supplies,
450				 wm8994->supplies);
451	if (ret != 0) {
452		dev_err(wm8994->dev, "Failed to get supplies: %d\n", ret);
453		goto err_supplies;
454	}
455
456	ret = regulator_bulk_enable(wm8994->num_supplies,
457				    wm8994->supplies);
458	if (ret != 0) {
459		dev_err(wm8994->dev, "Failed to enable supplies: %d\n", ret);
460		goto err_get;
461	}
462
463	ret = wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET);
464	if (ret < 0) {
465		dev_err(wm8994->dev, "Failed to read ID register\n");
466		goto err_enable;
467	}
468	switch (ret) {
469	case 0x8994:
470		devname = "WM8994";
471		if (wm8994->type != WM8994)
472			dev_warn(wm8994->dev, "Device registered as type %d\n",
473				 wm8994->type);
474		wm8994->type = WM8994;
475		break;
476	case 0x8958:
477		devname = "WM8958";
478		if (wm8994->type != WM8958)
479			dev_warn(wm8994->dev, "Device registered as type %d\n",
480				 wm8994->type);
481		wm8994->type = WM8958;
482		break;
483	default:
484		dev_err(wm8994->dev, "Device is not a WM8994, ID is %x\n",
485			ret);
486		ret = -EINVAL;
487		goto err_enable;
488	}
489
490	ret = wm8994_reg_read(wm8994, WM8994_CHIP_REVISION);
491	if (ret < 0) {
492		dev_err(wm8994->dev, "Failed to read revision register: %d\n",
493			ret);
494		goto err_enable;
495	}
496
497	switch (wm8994->type) {
498	case WM8994:
499		switch (ret) {
500		case 0:
501		case 1:
502			dev_warn(wm8994->dev,
503				 "revision %c not fully supported\n",
504				 'A' + ret);
505			break;
506		default:
507			break;
508		}
509		break;
510	default:
511		break;
512	}
513
514	dev_info(wm8994->dev, "%s revision %c\n", devname, 'A' + ret);
515
516	if (pdata) {
517		wm8994->irq_base = pdata->irq_base;
518		wm8994->gpio_base = pdata->gpio_base;
519
520		/* GPIO configuration is only applied if it's non-zero */
521		for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) {
522			if (pdata->gpio_defaults[i]) {
523				wm8994_set_bits(wm8994, WM8994_GPIO_1 + i,
524						0xffff,
525						pdata->gpio_defaults[i]);
526			}
527		}
528
529		wm8994->ldo_ena_always_driven = pdata->ldo_ena_always_driven;
530	}
531
532	/* Disable LDO pulldowns while the device is active */
533	wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
534			WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
535			0);
536
537	/* In some system designs where the regulators are not in use,
538	 * we can achieve a small reduction in leakage currents by
539	 * floating LDO outputs.  This bit makes no difference if the
540	 * LDOs are enabled, it only affects cases where the LDOs were
541	 * in operation and are then disabled.
542	 */
543	for (i = 0; i < WM8994_NUM_LDO_REGS; i++) {
544		if (wm8994_ldo_in_use(pdata, i))
545			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
546					WM8994_LDO1_DISCH, WM8994_LDO1_DISCH);
547		else
548			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
549					WM8994_LDO1_DISCH, 0);
550	}
551
552	wm8994_irq_init(wm8994);
553
554	ret = mfd_add_devices(wm8994->dev, -1,
555			      wm8994_devs, ARRAY_SIZE(wm8994_devs),
556			      NULL, 0);
557	if (ret != 0) {
558		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
559		goto err_irq;
560	}
561
562	pm_runtime_enable(wm8994->dev);
563	pm_runtime_resume(wm8994->dev);
564
565	return 0;
566
567err_irq:
568	wm8994_irq_exit(wm8994);
569err_enable:
570	regulator_bulk_disable(wm8994->num_supplies,
571			       wm8994->supplies);
572err_get:
573	regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);
574err_supplies:
575	kfree(wm8994->supplies);
576err:
577	mfd_remove_devices(wm8994->dev);
578	kfree(wm8994);
579	return ret;
580}
581
582static void wm8994_device_exit(struct wm8994 *wm8994)
583{
584	pm_runtime_disable(wm8994->dev);
585	mfd_remove_devices(wm8994->dev);
586	wm8994_irq_exit(wm8994);
587	regulator_bulk_disable(wm8994->num_supplies,
588			       wm8994->supplies);
589	regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);
590	kfree(wm8994->supplies);
591	kfree(wm8994);
592}
593
594static int wm8994_i2c_read_device(struct wm8994 *wm8994, unsigned short reg,
595				  int bytes, void *dest)
596{
597	struct i2c_client *i2c = wm8994->control_data;
598	int ret;
599	u16 r = cpu_to_be16(reg);
600
601	ret = i2c_master_send(i2c, (unsigned char *)&r, 2);
602	if (ret < 0)
603		return ret;
604	if (ret != 2)
605		return -EIO;
606
607	ret = i2c_master_recv(i2c, dest, bytes);
608	if (ret < 0)
609		return ret;
610	if (ret != bytes)
611		return -EIO;
612	return 0;
613}
614
615static int wm8994_i2c_write_device(struct wm8994 *wm8994, unsigned short reg,
616				   int bytes, const void *src)
617{
618	struct i2c_client *i2c = wm8994->control_data;
619	struct i2c_msg xfer[2];
620	int ret;
621
622	reg = cpu_to_be16(reg);
623
624	xfer[0].addr = i2c->addr;
625	xfer[0].flags = 0;
626	xfer[0].len = 2;
627	xfer[0].buf = (char *)&reg;
628
629	xfer[1].addr = i2c->addr;
630	xfer[1].flags = I2C_M_NOSTART;
631	xfer[1].len = bytes;
632	xfer[1].buf = (char *)src;
633
634	ret = i2c_transfer(i2c->adapter, xfer, 2);
635	if (ret < 0)
636		return ret;
637	if (ret != 2)
638		return -EIO;
639
640	return 0;
641}
642
643static int wm8994_i2c_probe(struct i2c_client *i2c,
644			    const struct i2c_device_id *id)
645{
646	struct wm8994 *wm8994;
647
648	wm8994 = kzalloc(sizeof(struct wm8994), GFP_KERNEL);
649	if (wm8994 == NULL)
650		return -ENOMEM;
651
652	i2c_set_clientdata(i2c, wm8994);
653	wm8994->dev = &i2c->dev;
654	wm8994->control_data = i2c;
655	wm8994->read_dev = wm8994_i2c_read_device;
656	wm8994->write_dev = wm8994_i2c_write_device;
657	wm8994->irq = i2c->irq;
658	wm8994->type = id->driver_data;
659
660	return wm8994_device_init(wm8994, i2c->irq);
661}
662
663static int wm8994_i2c_remove(struct i2c_client *i2c)
664{
665	struct wm8994 *wm8994 = i2c_get_clientdata(i2c);
666
667	wm8994_device_exit(wm8994);
668
669	return 0;
670}
671
672static const struct i2c_device_id wm8994_i2c_id[] = {
673	{ "wm8994", WM8994 },
674	{ "wm8958", WM8958 },
675	{ }
676};
677MODULE_DEVICE_TABLE(i2c, wm8994_i2c_id);
678
679static UNIVERSAL_DEV_PM_OPS(wm8994_pm_ops, wm8994_suspend, wm8994_resume,
680			    NULL);
681
682static struct i2c_driver wm8994_i2c_driver = {
683	.driver = {
684		.name = "wm8994",
685		.owner = THIS_MODULE,
686		.pm = &wm8994_pm_ops,
687	},
688	.probe = wm8994_i2c_probe,
689	.remove = wm8994_i2c_remove,
690	.id_table = wm8994_i2c_id,
691};
692
693static int __init wm8994_i2c_init(void)
694{
695	int ret;
696
697	ret = i2c_add_driver(&wm8994_i2c_driver);
698	if (ret != 0)
699		pr_err("Failed to register wm8994 I2C driver: %d\n", ret);
700
701	return ret;
702}
703module_init(wm8994_i2c_init);
704
705static void __exit wm8994_i2c_exit(void)
706{
707	i2c_del_driver(&wm8994_i2c_driver);
708}
709module_exit(wm8994_i2c_exit);
710
711MODULE_DESCRIPTION("Core support for the WM8994 audio CODEC");
712MODULE_LICENSE("GPL");
713MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
714