wm8994-core.c revision c9fbf7e070bbf9cc7adc1420df87706c62cb04ed
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/i2c.h>
18#include <linux/delay.h>
19#include <linux/mfd/core.h>
20#include <linux/regulator/consumer.h>
21#include <linux/regulator/machine.h>
22
23#include <linux/mfd/wm8994/core.h>
24#include <linux/mfd/wm8994/pdata.h>
25#include <linux/mfd/wm8994/registers.h>
26
27static int wm8994_read(struct wm8994 *wm8994, unsigned short reg,
28		       int bytes, void *dest)
29{
30	int ret, i;
31	u16 *buf = dest;
32
33	BUG_ON(bytes % 2);
34	BUG_ON(bytes <= 0);
35
36	ret = wm8994->read_dev(wm8994, reg, bytes, dest);
37	if (ret < 0)
38		return ret;
39
40	for (i = 0; i < bytes / 2; i++) {
41		buf[i] = be16_to_cpu(buf[i]);
42
43		dev_vdbg(wm8994->dev, "Read %04x from R%d(0x%x)\n",
44			 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 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.
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, void *src)
99{
100	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			 buf[i], reg + i, reg + i);
109
110		buf[i] = cpu_to_be16(buf[i]);
111	}
112
113	return wm8994->write_dev(wm8994, reg, bytes, src);
114}
115
116/**
117 * wm8994_reg_write: Write a single WM8994 register.
118 *
119 * @wm8994: Device to write to.
120 * @reg: Register to write to.
121 * @val: Value to write.
122 */
123int wm8994_reg_write(struct wm8994 *wm8994, unsigned short reg,
124		     unsigned short val)
125{
126	int ret;
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_set_bits: Set the value of a bitfield in a WM8994 register
140 *
141 * @wm8994: Device to write to.
142 * @reg: Register to write to.
143 * @mask: Mask of bits to set.
144 * @val: Value to set (unshifted)
145 */
146int wm8994_set_bits(struct wm8994 *wm8994, unsigned short reg,
147		    unsigned short mask, unsigned short val)
148{
149	int ret;
150	u16 r;
151
152	mutex_lock(&wm8994->io_lock);
153
154	ret = wm8994_read(wm8994, reg, 2, &r);
155	if (ret < 0)
156		goto out;
157
158	r &= ~mask;
159	r |= val;
160
161	ret = wm8994_write(wm8994, reg, 2, &r);
162
163out:
164	mutex_unlock(&wm8994->io_lock);
165
166	return ret;
167}
168EXPORT_SYMBOL_GPL(wm8994_set_bits);
169
170static struct mfd_cell wm8994_regulator_devs[] = {
171	{ .name = "wm8994-ldo", .id = 1 },
172	{ .name = "wm8994-ldo", .id = 2 },
173};
174
175static struct resource wm8994_codec_resources[] = {
176	{
177		.start = WM8994_IRQ_TEMP_SHUT,
178		.end   = WM8994_IRQ_TEMP_WARN,
179		.flags = IORESOURCE_IRQ,
180	},
181};
182
183static struct resource wm8994_gpio_resources[] = {
184	{
185		.start = WM8994_IRQ_GPIO(1),
186		.end   = WM8994_IRQ_GPIO(11),
187		.flags = IORESOURCE_IRQ,
188	},
189};
190
191static struct mfd_cell wm8994_devs[] = {
192	{
193		.name = "wm8994-codec",
194		.num_resources = ARRAY_SIZE(wm8994_codec_resources),
195		.resources = wm8994_codec_resources,
196	},
197
198	{
199		.name = "wm8994-gpio",
200		.num_resources = ARRAY_SIZE(wm8994_gpio_resources),
201		.resources = wm8994_gpio_resources,
202	},
203};
204
205/*
206 * Supplies for the main bulk of CODEC; the LDO supplies are ignored
207 * and should be handled via the standard regulator API supply
208 * management.
209 */
210static const char *wm8994_main_supplies[] = {
211	"DBVDD",
212	"DCVDD",
213	"AVDD1",
214	"AVDD2",
215	"CPVDD",
216	"SPKVDD1",
217	"SPKVDD2",
218};
219
220#ifdef CONFIG_PM
221static int wm8994_device_suspend(struct device *dev)
222{
223	struct wm8994 *wm8994 = dev_get_drvdata(dev);
224	int ret;
225
226	/* GPIO configuration state is saved here since we may be configuring
227	 * the GPIO alternate functions even if we're not using the gpiolib
228	 * driver for them.
229	 */
230	ret = wm8994_read(wm8994, WM8994_GPIO_1, WM8994_NUM_GPIO_REGS * 2,
231			  &wm8994->gpio_regs);
232	if (ret < 0)
233		dev_err(dev, "Failed to save GPIO registers: %d\n", ret);
234
235	/* For similar reasons we also stash the regulator states */
236	ret = wm8994_read(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
237			  &wm8994->ldo_regs);
238	if (ret < 0)
239		dev_err(dev, "Failed to save LDO registers: %d\n", ret);
240
241	ret = regulator_bulk_disable(ARRAY_SIZE(wm8994_main_supplies),
242				     wm8994->supplies);
243	if (ret != 0) {
244		dev_err(dev, "Failed to disable supplies: %d\n", ret);
245		return ret;
246	}
247
248	return 0;
249}
250
251static int wm8994_device_resume(struct device *dev)
252{
253	struct wm8994 *wm8994 = dev_get_drvdata(dev);
254	int ret;
255
256	ret = regulator_bulk_enable(ARRAY_SIZE(wm8994_main_supplies),
257				    wm8994->supplies);
258	if (ret != 0) {
259		dev_err(dev, "Failed to enable supplies: %d\n", ret);
260		return ret;
261	}
262
263	ret = wm8994_write(wm8994, WM8994_INTERRUPT_STATUS_1_MASK,
264			   WM8994_NUM_IRQ_REGS * 2, &wm8994->irq_masks_cur);
265	if (ret < 0)
266		dev_err(dev, "Failed to restore interrupt masks: %d\n", ret);
267
268	ret = wm8994_write(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
269			   &wm8994->ldo_regs);
270	if (ret < 0)
271		dev_err(dev, "Failed to restore LDO registers: %d\n", ret);
272
273	ret = wm8994_write(wm8994, WM8994_GPIO_1, WM8994_NUM_GPIO_REGS * 2,
274			   &wm8994->gpio_regs);
275	if (ret < 0)
276		dev_err(dev, "Failed to restore GPIO registers: %d\n", ret);
277
278	return 0;
279}
280#endif
281
282#ifdef CONFIG_REGULATOR
283static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
284{
285	struct wm8994_ldo_pdata *ldo_pdata;
286
287	if (!pdata)
288		return 0;
289
290	ldo_pdata = &pdata->ldo[ldo];
291
292	if (!ldo_pdata->init_data)
293		return 0;
294
295	return ldo_pdata->init_data->num_consumer_supplies != 0;
296}
297#else
298static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
299{
300	return 0;
301}
302#endif
303
304/*
305 * Instantiate the generic non-control parts of the device.
306 */
307static int wm8994_device_init(struct wm8994 *wm8994, unsigned long id, int irq)
308{
309	struct wm8994_pdata *pdata = wm8994->dev->platform_data;
310	int ret, i;
311
312	mutex_init(&wm8994->io_lock);
313	dev_set_drvdata(wm8994->dev, wm8994);
314
315	/* Add the on-chip regulators first for bootstrapping */
316	ret = mfd_add_devices(wm8994->dev, -1,
317			      wm8994_regulator_devs,
318			      ARRAY_SIZE(wm8994_regulator_devs),
319			      NULL, 0);
320	if (ret != 0) {
321		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
322		goto err;
323	}
324
325	wm8994->supplies = kzalloc(sizeof(struct regulator_bulk_data) *
326				   ARRAY_SIZE(wm8994_main_supplies),
327				   GFP_KERNEL);
328	if (!wm8994->supplies)
329		goto err;
330
331	for (i = 0; i < ARRAY_SIZE(wm8994_main_supplies); i++)
332		wm8994->supplies[i].supply = wm8994_main_supplies[i];
333
334	ret = regulator_bulk_get(wm8994->dev, ARRAY_SIZE(wm8994_main_supplies),
335				 wm8994->supplies);
336	if (ret != 0) {
337		dev_err(wm8994->dev, "Failed to get supplies: %d\n", ret);
338		goto err_supplies;
339	}
340
341	ret = regulator_bulk_enable(ARRAY_SIZE(wm8994_main_supplies),
342				    wm8994->supplies);
343	if (ret != 0) {
344		dev_err(wm8994->dev, "Failed to enable supplies: %d\n", ret);
345		goto err_get;
346	}
347
348	ret = wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET);
349	if (ret < 0) {
350		dev_err(wm8994->dev, "Failed to read ID register\n");
351		goto err_enable;
352	}
353	if (ret != 0x8994) {
354		dev_err(wm8994->dev, "Device is not a WM8994, ID is %x\n",
355			ret);
356		ret = -EINVAL;
357		goto err_enable;
358	}
359
360	ret = wm8994_reg_read(wm8994, WM8994_CHIP_REVISION);
361	if (ret < 0) {
362		dev_err(wm8994->dev, "Failed to read revision register: %d\n",
363			ret);
364		goto err_enable;
365	}
366
367	switch (ret) {
368	case 0:
369	case 1:
370		dev_warn(wm8994->dev, "revision %c not fully supported\n",
371			'A' + ret);
372		break;
373	default:
374		dev_info(wm8994->dev, "revision %c\n", 'A' + ret);
375		break;
376	}
377
378
379	if (pdata) {
380		wm8994->irq_base = pdata->irq_base;
381		wm8994->gpio_base = pdata->gpio_base;
382
383		/* GPIO configuration is only applied if it's non-zero */
384		for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) {
385			if (pdata->gpio_defaults[i]) {
386				wm8994_set_bits(wm8994, WM8994_GPIO_1 + i,
387						0xffff,
388						pdata->gpio_defaults[i]);
389			}
390		}
391	}
392
393	/* In some system designs where the regulators are not in use,
394	 * we can achieve a small reduction in leakage currents by
395	 * floating LDO outputs.  This bit makes no difference if the
396	 * LDOs are enabled, it only affects cases where the LDOs were
397	 * in operation and are then disabled.
398	 */
399	for (i = 0; i < WM8994_NUM_LDO_REGS; i++) {
400		if (wm8994_ldo_in_use(pdata, i))
401			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
402					WM8994_LDO1_DISCH, WM8994_LDO1_DISCH);
403		else
404			wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
405					WM8994_LDO1_DISCH, 0);
406	}
407
408	wm8994_irq_init(wm8994);
409
410	ret = mfd_add_devices(wm8994->dev, -1,
411			      wm8994_devs, ARRAY_SIZE(wm8994_devs),
412			      NULL, 0);
413	if (ret != 0) {
414		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
415		goto err_irq;
416	}
417
418	return 0;
419
420err_irq:
421	wm8994_irq_exit(wm8994);
422err_enable:
423	regulator_bulk_disable(ARRAY_SIZE(wm8994_main_supplies),
424			       wm8994->supplies);
425err_get:
426	regulator_bulk_free(ARRAY_SIZE(wm8994_main_supplies), wm8994->supplies);
427err_supplies:
428	kfree(wm8994->supplies);
429err:
430	mfd_remove_devices(wm8994->dev);
431	kfree(wm8994);
432	return ret;
433}
434
435static void wm8994_device_exit(struct wm8994 *wm8994)
436{
437	mfd_remove_devices(wm8994->dev);
438	wm8994_irq_exit(wm8994);
439	regulator_bulk_disable(ARRAY_SIZE(wm8994_main_supplies),
440			       wm8994->supplies);
441	regulator_bulk_free(ARRAY_SIZE(wm8994_main_supplies), wm8994->supplies);
442	kfree(wm8994->supplies);
443	kfree(wm8994);
444}
445
446static int wm8994_i2c_read_device(struct wm8994 *wm8994, unsigned short reg,
447				  int bytes, void *dest)
448{
449	struct i2c_client *i2c = wm8994->control_data;
450	int ret;
451	u16 r = cpu_to_be16(reg);
452
453	ret = i2c_master_send(i2c, (unsigned char *)&r, 2);
454	if (ret < 0)
455		return ret;
456	if (ret != 2)
457		return -EIO;
458
459	ret = i2c_master_recv(i2c, dest, bytes);
460	if (ret < 0)
461		return ret;
462	if (ret != bytes)
463		return -EIO;
464	return 0;
465}
466
467/* Currently we allocate the write buffer on the stack; this is OK for
468 * small writes - if we need to do large writes this will need to be
469 * revised.
470 */
471static int wm8994_i2c_write_device(struct wm8994 *wm8994, unsigned short reg,
472				   int bytes, void *src)
473{
474	struct i2c_client *i2c = wm8994->control_data;
475	unsigned char msg[bytes + 2];
476	int ret;
477
478	reg = cpu_to_be16(reg);
479	memcpy(&msg[0], &reg, 2);
480	memcpy(&msg[2], src, bytes);
481
482	ret = i2c_master_send(i2c, msg, bytes + 2);
483	if (ret < 0)
484		return ret;
485	if (ret < bytes + 2)
486		return -EIO;
487
488	return 0;
489}
490
491static int wm8994_i2c_probe(struct i2c_client *i2c,
492			    const struct i2c_device_id *id)
493{
494	struct wm8994 *wm8994;
495
496	wm8994 = kzalloc(sizeof(struct wm8994), GFP_KERNEL);
497	if (wm8994 == NULL) {
498		kfree(i2c);
499		return -ENOMEM;
500	}
501
502	i2c_set_clientdata(i2c, wm8994);
503	wm8994->dev = &i2c->dev;
504	wm8994->control_data = i2c;
505	wm8994->read_dev = wm8994_i2c_read_device;
506	wm8994->write_dev = wm8994_i2c_write_device;
507	wm8994->irq = i2c->irq;
508
509	return wm8994_device_init(wm8994, id->driver_data, i2c->irq);
510}
511
512static int wm8994_i2c_remove(struct i2c_client *i2c)
513{
514	struct wm8994 *wm8994 = i2c_get_clientdata(i2c);
515
516	wm8994_device_exit(wm8994);
517
518	return 0;
519}
520
521#ifdef CONFIG_PM
522static int wm8994_i2c_suspend(struct i2c_client *i2c, pm_message_t state)
523{
524	return wm8994_device_suspend(&i2c->dev);
525}
526
527static int wm8994_i2c_resume(struct i2c_client *i2c)
528{
529	return wm8994_device_resume(&i2c->dev);
530}
531#else
532#define wm8994_i2c_suspend NULL
533#define wm8994_i2c_resume NULL
534#endif
535
536static const struct i2c_device_id wm8994_i2c_id[] = {
537	{ "wm8994", 0 },
538	{ }
539};
540MODULE_DEVICE_TABLE(i2c, wm8994_i2c_id);
541
542static struct i2c_driver wm8994_i2c_driver = {
543	.driver = {
544		   .name = "wm8994",
545		   .owner = THIS_MODULE,
546	},
547	.probe = wm8994_i2c_probe,
548	.remove = wm8994_i2c_remove,
549	.suspend = wm8994_i2c_suspend,
550	.resume = wm8994_i2c_resume,
551	.id_table = wm8994_i2c_id,
552};
553
554static int __init wm8994_i2c_init(void)
555{
556	int ret;
557
558	ret = i2c_add_driver(&wm8994_i2c_driver);
559	if (ret != 0)
560		pr_err("Failed to register wm8994 I2C driver: %d\n", ret);
561
562	return ret;
563}
564module_init(wm8994_i2c_init);
565
566static void __exit wm8994_i2c_exit(void)
567{
568	i2c_del_driver(&wm8994_i2c_driver);
569}
570module_exit(wm8994_i2c_exit);
571
572MODULE_DESCRIPTION("Core support for the WM8994 audio CODEC");
573MODULE_LICENSE("GPL");
574MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
575