wm8994-core.c revision d450f19eea0c3f64d60dc37655bae03b2455e5bb 
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	/* GPIO configuration state is saved here since we may be configuring
250	 * the GPIO alternate functions even if we're not using the gpiolib
251	 * driver for them.
252	 */
253	ret = wm8994_read(wm8994, WM8994_GPIO_1, WM8994_NUM_GPIO_REGS * 2,
254			  &wm8994->gpio_regs);
255	if (ret < 0)
256		dev_err(dev, "Failed to save GPIO registers: %d\n", ret);
257
258	/* For similar reasons we also stash the regulator states */
259	ret = wm8994_read(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
260			  &wm8994->ldo_regs);
261	if (ret < 0)
262		dev_err(dev, "Failed to save LDO registers: %d\n", ret);
263
264	ret = regulator_bulk_disable(wm8994->num_supplies,
265				     wm8994->supplies);
266	if (ret != 0) {
267		dev_err(dev, "Failed to disable supplies: %d\n", ret);
268		return ret;
269	}
270
271	return 0;
272}
273
274static int wm8994_resume(struct device *dev)
275{
276	struct wm8994 *wm8994 = dev_get_drvdata(dev);
277	int ret;
278
279	ret = regulator_bulk_enable(wm8994->num_supplies,
280				    wm8994->supplies);
281	if (ret != 0) {
282		dev_err(dev, "Failed to enable supplies: %d\n", ret);
283		return ret;
284	}
285
286	ret = wm8994_write(wm8994, WM8994_INTERRUPT_STATUS_1_MASK,
287			   WM8994_NUM_IRQ_REGS * 2, &wm8994->irq_masks_cur);
288	if (ret < 0)
289		dev_err(dev, "Failed to restore interrupt masks: %d\n", ret);
290
291	ret = wm8994_write(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
292			   &wm8994->ldo_regs);
293	if (ret < 0)
294		dev_err(dev, "Failed to restore LDO registers: %d\n", ret);
295
296	ret = wm8994_write(wm8994, WM8994_GPIO_1, WM8994_NUM_GPIO_REGS * 2,
297			   &wm8994->gpio_regs);
298	if (ret < 0)
299		dev_err(dev, "Failed to restore GPIO registers: %d\n", ret);
300
301	return 0;
302}
303#endif
304
305#ifdef CONFIG_REGULATOR
306static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
307{
308	struct wm8994_ldo_pdata *ldo_pdata;
309
310	if (!pdata)
311		return 0;
312
313	ldo_pdata = &pdata->ldo[ldo];
314
315	if (!ldo_pdata->init_data)
316		return 0;
317
318	return ldo_pdata->init_data->num_consumer_supplies != 0;
319}
320#else
321static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
322{
323	return 0;
324}
325#endif
326
327/*
328 * Instantiate the generic non-control parts of the device.
329 */
330static int wm8994_device_init(struct wm8994 *wm8994, int irq)
331{
332	struct wm8994_pdata *pdata = wm8994->dev->platform_data;
333	const char *devname;
334	int ret, i;
335
336	mutex_init(&wm8994->io_lock);
337	dev_set_drvdata(wm8994->dev, wm8994);
338
339	/* Add the on-chip regulators first for bootstrapping */
340	ret = mfd_add_devices(wm8994->dev, -1,
341			      wm8994_regulator_devs,
342			      ARRAY_SIZE(wm8994_regulator_devs),
343			      NULL, 0);
344	if (ret != 0) {
345		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
346		goto err;
347	}
348
349	switch (wm8994->type) {
350	case WM8994:
351		wm8994->num_supplies = ARRAY_SIZE(wm8994_main_supplies);
352		break;
353	case WM8958:
354		wm8994->num_supplies = ARRAY_SIZE(wm8958_main_supplies);
355		break;
356	default:
357		BUG();
358		return -EINVAL;
359	}
360
361	wm8994->supplies = kzalloc(sizeof(struct regulator_bulk_data) *
362				   wm8994->num_supplies,
363				   GFP_KERNEL);
364	if (!wm8994->supplies) {
365		ret = -ENOMEM;
366		goto err;
367	}
368
369	switch (wm8994->type) {
370	case WM8994:
371		for (i = 0; i < ARRAY_SIZE(wm8994_main_supplies); i++)
372			wm8994->supplies[i].supply = wm8994_main_supplies[i];
373		break;
374	case WM8958:
375		for (i = 0; i < ARRAY_SIZE(wm8958_main_supplies); i++)
376			wm8994->supplies[i].supply = wm8958_main_supplies[i];
377		break;
378	default:
379		BUG();
380		return -EINVAL;
381	}
382
383	ret = regulator_bulk_get(wm8994->dev, wm8994->num_supplies,
384				 wm8994->supplies);
385	if (ret != 0) {
386		dev_err(wm8994->dev, "Failed to get supplies: %d\n", ret);
387		goto err_supplies;
388	}
389
390	ret = regulator_bulk_enable(wm8994->num_supplies,
391				    wm8994->supplies);
392	if (ret != 0) {
393		dev_err(wm8994->dev, "Failed to enable supplies: %d\n", ret);
394		goto err_get;
395	}
396
397	ret = wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET);
398	if (ret < 0) {
399		dev_err(wm8994->dev, "Failed to read ID register\n");
400		goto err_enable;
401	}
402	switch (ret) {
403	case 0x8994:
404		devname = "WM8994";
405		if (wm8994->type != WM8994)
406			dev_warn(wm8994->dev, "Device registered as type %d\n",
407				 wm8994->type);
408		wm8994->type = WM8994;
409		break;
410	case 0x8958:
411		devname = "WM8958";
412		if (wm8994->type != WM8958)
413			dev_warn(wm8994->dev, "Device registered as type %d\n",
414				 wm8994->type);
415		wm8994->type = WM8958;
416		break;
417	default:
418		dev_err(wm8994->dev, "Device is not a WM8994, ID is %x\n",
419			ret);
420		ret = -EINVAL;
421		goto err_enable;
422	}
423
424	ret = wm8994_reg_read(wm8994, WM8994_CHIP_REVISION);
425	if (ret < 0) {
426		dev_err(wm8994->dev, "Failed to read revision register: %d\n",
427			ret);
428		goto err_enable;
429	}
430
431	switch (ret) {
432	case 0:
433	case 1:
434		if (wm8994->type == WM8994)
435			dev_warn(wm8994->dev,
436				 "revision %c not fully supported\n",
437				 'A' + ret);
438		break;
439	default:
440		break;
441	}
442
443	dev_info(wm8994->dev, "%s revision %c\n", devname, 'A' + ret);
444
445	if (pdata) {
446		wm8994->irq_base = pdata->irq_base;
447		wm8994->gpio_base = pdata->gpio_base;
448
449		/* GPIO configuration is only applied if it's non-zero */
450		for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) {
451			if (pdata->gpio_defaults[i]) {
452				wm8994_set_bits(wm8994, WM8994_GPIO_1 + i,
453						0xffff,
454						pdata->gpio_defaults[i]);
455			}
456		}
457	}
458
459	/* In some system designs where the regulators are not in use,
460	 * we can achieve a small reduction in leakage currents by
461	 * floating LDO outputs.  This bit makes no difference if the
462	 * LDOs are enabled, it only affects cases where the LDOs were
463	 * in operation and are then disabled.
464	 */
465	for (i = 0; i < WM8994_NUM_LDO_REGS; i++) {
466		if (wm8994_ldo_in_use(pdata, i))
467			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
468					WM8994_LDO1_DISCH, WM8994_LDO1_DISCH);
469		else
470			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
471					WM8994_LDO1_DISCH, 0);
472	}
473
474	wm8994_irq_init(wm8994);
475
476	ret = mfd_add_devices(wm8994->dev, -1,
477			      wm8994_devs, ARRAY_SIZE(wm8994_devs),
478			      NULL, 0);
479	if (ret != 0) {
480		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
481		goto err_irq;
482	}
483
484	pm_runtime_enable(wm8994->dev);
485	pm_runtime_resume(wm8994->dev);
486
487	return 0;
488
489err_irq:
490	wm8994_irq_exit(wm8994);
491err_enable:
492	regulator_bulk_disable(wm8994->num_supplies,
493			       wm8994->supplies);
494err_get:
495	regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);
496err_supplies:
497	kfree(wm8994->supplies);
498err:
499	mfd_remove_devices(wm8994->dev);
500	kfree(wm8994);
501	return ret;
502}
503
504static void wm8994_device_exit(struct wm8994 *wm8994)
505{
506	pm_runtime_disable(wm8994->dev);
507	mfd_remove_devices(wm8994->dev);
508	wm8994_irq_exit(wm8994);
509	regulator_bulk_disable(wm8994->num_supplies,
510			       wm8994->supplies);
511	regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);
512	kfree(wm8994->supplies);
513	kfree(wm8994);
514}
515
516static int wm8994_i2c_read_device(struct wm8994 *wm8994, unsigned short reg,
517				  int bytes, void *dest)
518{
519	struct i2c_client *i2c = wm8994->control_data;
520	int ret;
521	u16 r = cpu_to_be16(reg);
522
523	ret = i2c_master_send(i2c, (unsigned char *)&r, 2);
524	if (ret < 0)
525		return ret;
526	if (ret != 2)
527		return -EIO;
528
529	ret = i2c_master_recv(i2c, dest, bytes);
530	if (ret < 0)
531		return ret;
532	if (ret != bytes)
533		return -EIO;
534	return 0;
535}
536
537/* Currently we allocate the write buffer on the stack; this is OK for
538 * small writes - if we need to do large writes this will need to be
539 * revised.
540 */
541static int wm8994_i2c_write_device(struct wm8994 *wm8994, unsigned short reg,
542				   int bytes, void *src)
543{
544	struct i2c_client *i2c = wm8994->control_data;
545	unsigned char msg[bytes + 2];
546	int ret;
547
548	reg = cpu_to_be16(reg);
549	memcpy(&msg[0], &reg, 2);
550	memcpy(&msg[2], src, bytes);
551
552	ret = i2c_master_send(i2c, msg, bytes + 2);
553	if (ret < 0)
554		return ret;
555	if (ret < bytes + 2)
556		return -EIO;
557
558	return 0;
559}
560
561static int wm8994_i2c_probe(struct i2c_client *i2c,
562			    const struct i2c_device_id *id)
563{
564	struct wm8994 *wm8994;
565
566	wm8994 = kzalloc(sizeof(struct wm8994), GFP_KERNEL);
567	if (wm8994 == NULL)
568		return -ENOMEM;
569
570	i2c_set_clientdata(i2c, wm8994);
571	wm8994->dev = &i2c->dev;
572	wm8994->control_data = i2c;
573	wm8994->read_dev = wm8994_i2c_read_device;
574	wm8994->write_dev = wm8994_i2c_write_device;
575	wm8994->irq = i2c->irq;
576	wm8994->type = id->driver_data;
577
578	return wm8994_device_init(wm8994, i2c->irq);
579}
580
581static int wm8994_i2c_remove(struct i2c_client *i2c)
582{
583	struct wm8994 *wm8994 = i2c_get_clientdata(i2c);
584
585	wm8994_device_exit(wm8994);
586
587	return 0;
588}
589
590static const struct i2c_device_id wm8994_i2c_id[] = {
591	{ "wm8994", WM8994 },
592	{ "wm8958", WM8958 },
593	{ }
594};
595MODULE_DEVICE_TABLE(i2c, wm8994_i2c_id);
596
597UNIVERSAL_DEV_PM_OPS(wm8994_pm_ops, wm8994_suspend, wm8994_resume, NULL);
598
599static struct i2c_driver wm8994_i2c_driver = {
600	.driver = {
601		.name = "wm8994",
602		.owner = THIS_MODULE,
603		.pm = &wm8994_pm_ops,
604	},
605	.probe = wm8994_i2c_probe,
606	.remove = wm8994_i2c_remove,
607	.id_table = wm8994_i2c_id,
608};
609
610static int __init wm8994_i2c_init(void)
611{
612	int ret;
613
614	ret = i2c_add_driver(&wm8994_i2c_driver);
615	if (ret != 0)
616		pr_err("Failed to register wm8994 I2C driver: %d\n", ret);
617
618	return ret;
619}
620module_init(wm8994_i2c_init);
621
622static void __exit wm8994_i2c_exit(void)
623{
624	i2c_del_driver(&wm8994_i2c_driver);
625}
626module_exit(wm8994_i2c_exit);
627
628MODULE_DESCRIPTION("Core support for the WM8994 audio CODEC");
629MODULE_LICENSE("GPL");
630MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
631