wm8994-core.c revision 77bd70e9009eab6dbdef3ee08afe87ab26df8dac 
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		buf[i] = be16_to_cpu(buf[i]);
44
45		dev_vdbg(wm8994->dev, "Read %04x from R%d(0x%x)\n",
46			 buf[i], reg + i, reg + i);
47	}
48
49	return 0;
50}
51
52/**
53 * wm8994_reg_read: Read a single WM8994 register.
54 *
55 * @wm8994: Device to read from.
56 * @reg: Register to read.
57 */
58int wm8994_reg_read(struct wm8994 *wm8994, unsigned short reg)
59{
60	unsigned short val;
61	int ret;
62
63	mutex_lock(&wm8994->io_lock);
64
65	ret = wm8994_read(wm8994, reg, 2, &val);
66
67	mutex_unlock(&wm8994->io_lock);
68
69	if (ret < 0)
70		return ret;
71	else
72		return val;
73}
74EXPORT_SYMBOL_GPL(wm8994_reg_read);
75
76/**
77 * wm8994_bulk_read: Read multiple WM8994 registers
78 *
79 * @wm8994: Device to read from
80 * @reg: First register
81 * @count: Number of registers
82 * @buf: Buffer to fill.
83 */
84int wm8994_bulk_read(struct wm8994 *wm8994, unsigned short reg,
85		     int count, u16 *buf)
86{
87	int ret;
88
89	mutex_lock(&wm8994->io_lock);
90
91	ret = wm8994_read(wm8994, reg, count * 2, buf);
92
93	mutex_unlock(&wm8994->io_lock);
94
95	return ret;
96}
97EXPORT_SYMBOL_GPL(wm8994_bulk_read);
98
99static int wm8994_write(struct wm8994 *wm8994, unsigned short reg,
100			int bytes, void *src)
101{
102	u16 *buf = src;
103	int i;
104
105	BUG_ON(bytes % 2);
106	BUG_ON(bytes <= 0);
107
108	for (i = 0; i < bytes / 2; i++) {
109		dev_vdbg(wm8994->dev, "Write %04x to R%d(0x%x)\n",
110			 buf[i], reg + i, reg + i);
111
112		buf[i] = cpu_to_be16(buf[i]);
113	}
114
115	return wm8994->write_dev(wm8994, reg, bytes, src);
116}
117
118/**
119 * wm8994_reg_write: Write a single WM8994 register.
120 *
121 * @wm8994: Device to write to.
122 * @reg: Register to write to.
123 * @val: Value to write.
124 */
125int wm8994_reg_write(struct wm8994 *wm8994, unsigned short reg,
126		     unsigned short val)
127{
128	int ret;
129
130	mutex_lock(&wm8994->io_lock);
131
132	ret = wm8994_write(wm8994, reg, 2, &val);
133
134	mutex_unlock(&wm8994->io_lock);
135
136	return ret;
137}
138EXPORT_SYMBOL_GPL(wm8994_reg_write);
139
140/**
141 * wm8994_set_bits: Set the value of a bitfield in a WM8994 register
142 *
143 * @wm8994: Device to write to.
144 * @reg: Register to write to.
145 * @mask: Mask of bits to set.
146 * @val: Value to set (unshifted)
147 */
148int wm8994_set_bits(struct wm8994 *wm8994, unsigned short reg,
149		    unsigned short mask, unsigned short val)
150{
151	int ret;
152	u16 r;
153
154	mutex_lock(&wm8994->io_lock);
155
156	ret = wm8994_read(wm8994, reg, 2, &r);
157	if (ret < 0)
158		goto out;
159
160	r &= ~mask;
161	r |= val;
162
163	ret = wm8994_write(wm8994, reg, 2, &r);
164
165out:
166	mutex_unlock(&wm8994->io_lock);
167
168	return ret;
169}
170EXPORT_SYMBOL_GPL(wm8994_set_bits);
171
172static struct mfd_cell wm8994_regulator_devs[] = {
173	{
174		.name = "wm8994-ldo",
175		.id = 1,
176		.pm_runtime_no_callbacks = true,
177	},
178	{
179		.name = "wm8994-ldo",
180		.id = 2,
181		.pm_runtime_no_callbacks = true,
182	},
183};
184
185static struct resource wm8994_codec_resources[] = {
186	{
187		.start = WM8994_IRQ_TEMP_SHUT,
188		.end   = WM8994_IRQ_TEMP_WARN,
189		.flags = IORESOURCE_IRQ,
190	},
191};
192
193static struct resource wm8994_gpio_resources[] = {
194	{
195		.start = WM8994_IRQ_GPIO(1),
196		.end   = WM8994_IRQ_GPIO(11),
197		.flags = IORESOURCE_IRQ,
198	},
199};
200
201static struct mfd_cell wm8994_devs[] = {
202	{
203		.name = "wm8994-codec",
204		.num_resources = ARRAY_SIZE(wm8994_codec_resources),
205		.resources = wm8994_codec_resources,
206	},
207
208	{
209		.name = "wm8994-gpio",
210		.num_resources = ARRAY_SIZE(wm8994_gpio_resources),
211		.resources = wm8994_gpio_resources,
212		.pm_runtime_no_callbacks = true,
213	},
214};
215
216/*
217 * Supplies for the main bulk of CODEC; the LDO supplies are ignored
218 * and should be handled via the standard regulator API supply
219 * management.
220 */
221static const char *wm8994_main_supplies[] = {
222	"DBVDD",
223	"DCVDD",
224	"AVDD1",
225	"AVDD2",
226	"CPVDD",
227	"SPKVDD1",
228	"SPKVDD2",
229};
230
231static const char *wm8958_main_supplies[] = {
232	"DBVDD1",
233	"DBVDD2",
234	"DBVDD3",
235	"DCVDD",
236	"AVDD1",
237	"AVDD2",
238	"CPVDD",
239	"SPKVDD1",
240	"SPKVDD2",
241};
242
243#ifdef CONFIG_PM
244static int wm8994_suspend(struct device *dev)
245{
246	struct wm8994 *wm8994 = dev_get_drvdata(dev);
247	int ret;
248
249	/* Don't actually go through with the suspend if the CODEC is
250	 * still active (eg, for audio passthrough from CP. */
251	ret = wm8994_reg_read(wm8994, WM8994_POWER_MANAGEMENT_1);
252	if (ret < 0) {
253		dev_err(dev, "Failed to read power status: %d\n", ret);
254	} else if (ret & WM8994_VMID_SEL_MASK) {
255		dev_dbg(dev, "CODEC still active, ignoring suspend\n");
256		return 0;
257	}
258
259	/* GPIO configuration state is saved here since we may be configuring
260	 * the GPIO alternate functions even if we're not using the gpiolib
261	 * driver for them.
262	 */
263	ret = wm8994_read(wm8994, WM8994_GPIO_1, WM8994_NUM_GPIO_REGS * 2,
264			  &wm8994->gpio_regs);
265	if (ret < 0)
266		dev_err(dev, "Failed to save GPIO registers: %d\n", ret);
267
268	/* For similar reasons we also stash the regulator states */
269	ret = wm8994_read(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
270			  &wm8994->ldo_regs);
271	if (ret < 0)
272		dev_err(dev, "Failed to save LDO registers: %d\n", ret);
273
274	wm8994->suspended = true;
275
276	ret = regulator_bulk_disable(wm8994->num_supplies,
277				     wm8994->supplies);
278	if (ret != 0) {
279		dev_err(dev, "Failed to disable supplies: %d\n", ret);
280		return ret;
281	}
282
283	return 0;
284}
285
286static int wm8994_resume(struct device *dev)
287{
288	struct wm8994 *wm8994 = dev_get_drvdata(dev);
289	int ret;
290
291	/* We may have lied to the PM core about suspending */
292	if (!wm8994->suspended)
293		return 0;
294
295	ret = regulator_bulk_enable(wm8994->num_supplies,
296				    wm8994->supplies);
297	if (ret != 0) {
298		dev_err(dev, "Failed to enable supplies: %d\n", ret);
299		return ret;
300	}
301
302	ret = wm8994_write(wm8994, WM8994_INTERRUPT_STATUS_1_MASK,
303			   WM8994_NUM_IRQ_REGS * 2, &wm8994->irq_masks_cur);
304	if (ret < 0)
305		dev_err(dev, "Failed to restore interrupt masks: %d\n", ret);
306
307	ret = wm8994_write(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
308			   &wm8994->ldo_regs);
309	if (ret < 0)
310		dev_err(dev, "Failed to restore LDO registers: %d\n", ret);
311
312	ret = wm8994_write(wm8994, WM8994_GPIO_1, WM8994_NUM_GPIO_REGS * 2,
313			   &wm8994->gpio_regs);
314	if (ret < 0)
315		dev_err(dev, "Failed to restore GPIO registers: %d\n", ret);
316
317	wm8994->suspended = false;
318
319	return 0;
320}
321#endif
322
323#ifdef CONFIG_REGULATOR
324static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
325{
326	struct wm8994_ldo_pdata *ldo_pdata;
327
328	if (!pdata)
329		return 0;
330
331	ldo_pdata = &pdata->ldo[ldo];
332
333	if (!ldo_pdata->init_data)
334		return 0;
335
336	return ldo_pdata->init_data->num_consumer_supplies != 0;
337}
338#else
339static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
340{
341	return 0;
342}
343#endif
344
345/*
346 * Instantiate the generic non-control parts of the device.
347 */
348static int wm8994_device_init(struct wm8994 *wm8994, int irq)
349{
350	struct wm8994_pdata *pdata = wm8994->dev->platform_data;
351	const char *devname;
352	int ret, i;
353
354	mutex_init(&wm8994->io_lock);
355	dev_set_drvdata(wm8994->dev, wm8994);
356
357	/* Add the on-chip regulators first for bootstrapping */
358	ret = mfd_add_devices(wm8994->dev, -1,
359			      wm8994_regulator_devs,
360			      ARRAY_SIZE(wm8994_regulator_devs),
361			      NULL, 0);
362	if (ret != 0) {
363		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
364		goto err;
365	}
366
367	switch (wm8994->type) {
368	case WM8994:
369		wm8994->num_supplies = ARRAY_SIZE(wm8994_main_supplies);
370		break;
371	case WM8958:
372		wm8994->num_supplies = ARRAY_SIZE(wm8958_main_supplies);
373		break;
374	default:
375		BUG();
376		return -EINVAL;
377	}
378
379	wm8994->supplies = kzalloc(sizeof(struct regulator_bulk_data) *
380				   wm8994->num_supplies,
381				   GFP_KERNEL);
382	if (!wm8994->supplies) {
383		ret = -ENOMEM;
384		goto err;
385	}
386
387	switch (wm8994->type) {
388	case WM8994:
389		for (i = 0; i < ARRAY_SIZE(wm8994_main_supplies); i++)
390			wm8994->supplies[i].supply = wm8994_main_supplies[i];
391		break;
392	case WM8958:
393		for (i = 0; i < ARRAY_SIZE(wm8958_main_supplies); i++)
394			wm8994->supplies[i].supply = wm8958_main_supplies[i];
395		break;
396	default:
397		BUG();
398		return -EINVAL;
399	}
400
401	ret = regulator_bulk_get(wm8994->dev, wm8994->num_supplies,
402				 wm8994->supplies);
403	if (ret != 0) {
404		dev_err(wm8994->dev, "Failed to get supplies: %d\n", ret);
405		goto err_supplies;
406	}
407
408	ret = regulator_bulk_enable(wm8994->num_supplies,
409				    wm8994->supplies);
410	if (ret != 0) {
411		dev_err(wm8994->dev, "Failed to enable supplies: %d\n", ret);
412		goto err_get;
413	}
414
415	ret = wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET);
416	if (ret < 0) {
417		dev_err(wm8994->dev, "Failed to read ID register\n");
418		goto err_enable;
419	}
420	switch (ret) {
421	case 0x8994:
422		devname = "WM8994";
423		if (wm8994->type != WM8994)
424			dev_warn(wm8994->dev, "Device registered as type %d\n",
425				 wm8994->type);
426		wm8994->type = WM8994;
427		break;
428	case 0x8958:
429		devname = "WM8958";
430		if (wm8994->type != WM8958)
431			dev_warn(wm8994->dev, "Device registered as type %d\n",
432				 wm8994->type);
433		wm8994->type = WM8958;
434		break;
435	default:
436		dev_err(wm8994->dev, "Device is not a WM8994, ID is %x\n",
437			ret);
438		ret = -EINVAL;
439		goto err_enable;
440	}
441
442	ret = wm8994_reg_read(wm8994, WM8994_CHIP_REVISION);
443	if (ret < 0) {
444		dev_err(wm8994->dev, "Failed to read revision register: %d\n",
445			ret);
446		goto err_enable;
447	}
448
449	switch (ret) {
450	case 0:
451	case 1:
452		if (wm8994->type == WM8994)
453			dev_warn(wm8994->dev,
454				 "revision %c not fully supported\n",
455				 'A' + ret);
456		break;
457	default:
458		break;
459	}
460
461	dev_info(wm8994->dev, "%s revision %c\n", devname, 'A' + ret);
462
463	if (pdata) {
464		wm8994->irq_base = pdata->irq_base;
465		wm8994->gpio_base = pdata->gpio_base;
466
467		/* GPIO configuration is only applied if it's non-zero */
468		for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) {
469			if (pdata->gpio_defaults[i]) {
470				wm8994_set_bits(wm8994, WM8994_GPIO_1 + i,
471						0xffff,
472						pdata->gpio_defaults[i]);
473			}
474		}
475	}
476
477	/* In some system designs where the regulators are not in use,
478	 * we can achieve a small reduction in leakage currents by
479	 * floating LDO outputs.  This bit makes no difference if the
480	 * LDOs are enabled, it only affects cases where the LDOs were
481	 * in operation and are then disabled.
482	 */
483	for (i = 0; i < WM8994_NUM_LDO_REGS; i++) {
484		if (wm8994_ldo_in_use(pdata, i))
485			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
486					WM8994_LDO1_DISCH, WM8994_LDO1_DISCH);
487		else
488			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
489					WM8994_LDO1_DISCH, 0);
490	}
491
492	wm8994_irq_init(wm8994);
493
494	ret = mfd_add_devices(wm8994->dev, -1,
495			      wm8994_devs, ARRAY_SIZE(wm8994_devs),
496			      NULL, 0);
497	if (ret != 0) {
498		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
499		goto err_irq;
500	}
501
502	pm_runtime_enable(wm8994->dev);
503	pm_runtime_resume(wm8994->dev);
504
505	return 0;
506
507err_irq:
508	wm8994_irq_exit(wm8994);
509err_enable:
510	regulator_bulk_disable(wm8994->num_supplies,
511			       wm8994->supplies);
512err_get:
513	regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);
514err_supplies:
515	kfree(wm8994->supplies);
516err:
517	mfd_remove_devices(wm8994->dev);
518	kfree(wm8994);
519	return ret;
520}
521
522static void wm8994_device_exit(struct wm8994 *wm8994)
523{
524	pm_runtime_disable(wm8994->dev);
525	mfd_remove_devices(wm8994->dev);
526	wm8994_irq_exit(wm8994);
527	regulator_bulk_disable(wm8994->num_supplies,
528			       wm8994->supplies);
529	regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);
530	kfree(wm8994->supplies);
531	kfree(wm8994);
532}
533
534static int wm8994_i2c_read_device(struct wm8994 *wm8994, unsigned short reg,
535				  int bytes, void *dest)
536{
537	struct i2c_client *i2c = wm8994->control_data;
538	int ret;
539	u16 r = cpu_to_be16(reg);
540
541	ret = i2c_master_send(i2c, (unsigned char *)&r, 2);
542	if (ret < 0)
543		return ret;
544	if (ret != 2)
545		return -EIO;
546
547	ret = i2c_master_recv(i2c, dest, bytes);
548	if (ret < 0)
549		return ret;
550	if (ret != bytes)
551		return -EIO;
552	return 0;
553}
554
555/* Currently we allocate the write buffer on the stack; this is OK for
556 * small writes - if we need to do large writes this will need to be
557 * revised.
558 */
559static int wm8994_i2c_write_device(struct wm8994 *wm8994, unsigned short reg,
560				   int bytes, void *src)
561{
562	struct i2c_client *i2c = wm8994->control_data;
563	unsigned char msg[bytes + 2];
564	int ret;
565
566	reg = cpu_to_be16(reg);
567	memcpy(&msg[0], &reg, 2);
568	memcpy(&msg[2], src, bytes);
569
570	ret = i2c_master_send(i2c, msg, bytes + 2);
571	if (ret < 0)
572		return ret;
573	if (ret < bytes + 2)
574		return -EIO;
575
576	return 0;
577}
578
579static int wm8994_i2c_probe(struct i2c_client *i2c,
580			    const struct i2c_device_id *id)
581{
582	struct wm8994 *wm8994;
583
584	wm8994 = kzalloc(sizeof(struct wm8994), GFP_KERNEL);
585	if (wm8994 == NULL)
586		return -ENOMEM;
587
588	i2c_set_clientdata(i2c, wm8994);
589	wm8994->dev = &i2c->dev;
590	wm8994->control_data = i2c;
591	wm8994->read_dev = wm8994_i2c_read_device;
592	wm8994->write_dev = wm8994_i2c_write_device;
593	wm8994->irq = i2c->irq;
594	wm8994->type = id->driver_data;
595
596	return wm8994_device_init(wm8994, i2c->irq);
597}
598
599static int wm8994_i2c_remove(struct i2c_client *i2c)
600{
601	struct wm8994 *wm8994 = i2c_get_clientdata(i2c);
602
603	wm8994_device_exit(wm8994);
604
605	return 0;
606}
607
608static const struct i2c_device_id wm8994_i2c_id[] = {
609	{ "wm8994", WM8994 },
610	{ "wm8958", WM8958 },
611	{ }
612};
613MODULE_DEVICE_TABLE(i2c, wm8994_i2c_id);
614
615UNIVERSAL_DEV_PM_OPS(wm8994_pm_ops, wm8994_suspend, wm8994_resume, NULL);
616
617static struct i2c_driver wm8994_i2c_driver = {
618	.driver = {
619		.name = "wm8994",
620		.owner = THIS_MODULE,
621		.pm = &wm8994_pm_ops,
622	},
623	.probe = wm8994_i2c_probe,
624	.remove = wm8994_i2c_remove,
625	.id_table = wm8994_i2c_id,
626};
627
628static int __init wm8994_i2c_init(void)
629{
630	int ret;
631
632	ret = i2c_add_driver(&wm8994_i2c_driver);
633	if (ret != 0)
634		pr_err("Failed to register wm8994 I2C driver: %d\n", ret);
635
636	return ret;
637}
638module_init(wm8994_i2c_init);
639
640static void __exit wm8994_i2c_exit(void)
641{
642	i2c_del_driver(&wm8994_i2c_driver);
643}
644module_exit(wm8994_i2c_exit);
645
646MODULE_DESCRIPTION("Core support for the WM8994 audio CODEC");
647MODULE_LICENSE("GPL");
648MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
649