1/*
2 * linux/drivers/mfd/aat2870-core.c
3 *
4 * Copyright (c) 2011, NVIDIA Corporation.
5 * Author: Jin Park <jinyoungp@nvidia.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * version 2 as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
19 * 02110-1301 USA
20 */
21
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/init.h>
25#include <linux/debugfs.h>
26#include <linux/slab.h>
27#include <linux/uaccess.h>
28#include <linux/i2c.h>
29#include <linux/delay.h>
30#include <linux/gpio.h>
31#include <linux/mfd/core.h>
32#include <linux/mfd/aat2870.h>
33#include <linux/regulator/machine.h>
34
35static struct aat2870_register aat2870_regs[AAT2870_REG_NUM] = {
36	/* readable, writeable, value */
37	{ 0, 1, 0x00 },	/* 0x00 AAT2870_BL_CH_EN */
38	{ 0, 1, 0x16 },	/* 0x01 AAT2870_BLM */
39	{ 0, 1, 0x16 },	/* 0x02 AAT2870_BLS */
40	{ 0, 1, 0x56 },	/* 0x03 AAT2870_BL1 */
41	{ 0, 1, 0x56 },	/* 0x04 AAT2870_BL2 */
42	{ 0, 1, 0x56 },	/* 0x05 AAT2870_BL3 */
43	{ 0, 1, 0x56 },	/* 0x06 AAT2870_BL4 */
44	{ 0, 1, 0x56 },	/* 0x07 AAT2870_BL5 */
45	{ 0, 1, 0x56 },	/* 0x08 AAT2870_BL6 */
46	{ 0, 1, 0x56 },	/* 0x09 AAT2870_BL7 */
47	{ 0, 1, 0x56 },	/* 0x0A AAT2870_BL8 */
48	{ 0, 1, 0x00 },	/* 0x0B AAT2870_FLR */
49	{ 0, 1, 0x03 },	/* 0x0C AAT2870_FM */
50	{ 0, 1, 0x03 },	/* 0x0D AAT2870_FS */
51	{ 0, 1, 0x10 },	/* 0x0E AAT2870_ALS_CFG0 */
52	{ 0, 1, 0x06 },	/* 0x0F AAT2870_ALS_CFG1 */
53	{ 0, 1, 0x00 },	/* 0x10 AAT2870_ALS_CFG2 */
54	{ 1, 0, 0x00 },	/* 0x11 AAT2870_AMB */
55	{ 0, 1, 0x00 },	/* 0x12 AAT2870_ALS0 */
56	{ 0, 1, 0x00 },	/* 0x13 AAT2870_ALS1 */
57	{ 0, 1, 0x00 },	/* 0x14 AAT2870_ALS2 */
58	{ 0, 1, 0x00 },	/* 0x15 AAT2870_ALS3 */
59	{ 0, 1, 0x00 },	/* 0x16 AAT2870_ALS4 */
60	{ 0, 1, 0x00 },	/* 0x17 AAT2870_ALS5 */
61	{ 0, 1, 0x00 },	/* 0x18 AAT2870_ALS6 */
62	{ 0, 1, 0x00 },	/* 0x19 AAT2870_ALS7 */
63	{ 0, 1, 0x00 },	/* 0x1A AAT2870_ALS8 */
64	{ 0, 1, 0x00 },	/* 0x1B AAT2870_ALS9 */
65	{ 0, 1, 0x00 },	/* 0x1C AAT2870_ALSA */
66	{ 0, 1, 0x00 },	/* 0x1D AAT2870_ALSB */
67	{ 0, 1, 0x00 },	/* 0x1E AAT2870_ALSC */
68	{ 0, 1, 0x00 },	/* 0x1F AAT2870_ALSD */
69	{ 0, 1, 0x00 },	/* 0x20 AAT2870_ALSE */
70	{ 0, 1, 0x00 },	/* 0x21 AAT2870_ALSF */
71	{ 0, 1, 0x00 },	/* 0x22 AAT2870_SUB_SET */
72	{ 0, 1, 0x00 },	/* 0x23 AAT2870_SUB_CTRL */
73	{ 0, 1, 0x00 },	/* 0x24 AAT2870_LDO_AB */
74	{ 0, 1, 0x00 },	/* 0x25 AAT2870_LDO_CD */
75	{ 0, 1, 0x00 },	/* 0x26 AAT2870_LDO_EN */
76};
77
78static struct mfd_cell aat2870_devs[] = {
79	{
80		.name = "aat2870-backlight",
81		.id = AAT2870_ID_BL,
82		.pdata_size = sizeof(struct aat2870_bl_platform_data),
83	},
84	{
85		.name = "aat2870-regulator",
86		.id = AAT2870_ID_LDOA,
87		.pdata_size = sizeof(struct regulator_init_data),
88	},
89	{
90		.name = "aat2870-regulator",
91		.id = AAT2870_ID_LDOB,
92		.pdata_size = sizeof(struct regulator_init_data),
93	},
94	{
95		.name = "aat2870-regulator",
96		.id = AAT2870_ID_LDOC,
97		.pdata_size = sizeof(struct regulator_init_data),
98	},
99	{
100		.name = "aat2870-regulator",
101		.id = AAT2870_ID_LDOD,
102		.pdata_size = sizeof(struct regulator_init_data),
103	},
104};
105
106static int __aat2870_read(struct aat2870_data *aat2870, u8 addr, u8 *val)
107{
108	int ret;
109
110	if (addr >= AAT2870_REG_NUM) {
111		dev_err(aat2870->dev, "Invalid address, 0x%02x\n", addr);
112		return -EINVAL;
113	}
114
115	if (!aat2870->reg_cache[addr].readable) {
116		*val = aat2870->reg_cache[addr].value;
117		goto out;
118	}
119
120	ret = i2c_master_send(aat2870->client, &addr, 1);
121	if (ret < 0)
122		return ret;
123	if (ret != 1)
124		return -EIO;
125
126	ret = i2c_master_recv(aat2870->client, val, 1);
127	if (ret < 0)
128		return ret;
129	if (ret != 1)
130		return -EIO;
131
132out:
133	dev_dbg(aat2870->dev, "read: addr=0x%02x, val=0x%02x\n", addr, *val);
134	return 0;
135}
136
137static int __aat2870_write(struct aat2870_data *aat2870, u8 addr, u8 val)
138{
139	u8 msg[2];
140	int ret;
141
142	if (addr >= AAT2870_REG_NUM) {
143		dev_err(aat2870->dev, "Invalid address, 0x%02x\n", addr);
144		return -EINVAL;
145	}
146
147	if (!aat2870->reg_cache[addr].writeable) {
148		dev_err(aat2870->dev, "Address 0x%02x is not writeable\n",
149			addr);
150		return -EINVAL;
151	}
152
153	msg[0] = addr;
154	msg[1] = val;
155	ret = i2c_master_send(aat2870->client, msg, 2);
156	if (ret < 0)
157		return ret;
158	if (ret != 2)
159		return -EIO;
160
161	aat2870->reg_cache[addr].value = val;
162
163	dev_dbg(aat2870->dev, "write: addr=0x%02x, val=0x%02x\n", addr, val);
164	return 0;
165}
166
167static int aat2870_read(struct aat2870_data *aat2870, u8 addr, u8 *val)
168{
169	int ret;
170
171	mutex_lock(&aat2870->io_lock);
172	ret = __aat2870_read(aat2870, addr, val);
173	mutex_unlock(&aat2870->io_lock);
174
175	return ret;
176}
177
178static int aat2870_write(struct aat2870_data *aat2870, u8 addr, u8 val)
179{
180	int ret;
181
182	mutex_lock(&aat2870->io_lock);
183	ret = __aat2870_write(aat2870, addr, val);
184	mutex_unlock(&aat2870->io_lock);
185
186	return ret;
187}
188
189static int aat2870_update(struct aat2870_data *aat2870, u8 addr, u8 mask,
190			  u8 val)
191{
192	int change;
193	u8 old_val, new_val;
194	int ret;
195
196	mutex_lock(&aat2870->io_lock);
197
198	ret = __aat2870_read(aat2870, addr, &old_val);
199	if (ret)
200		goto out_unlock;
201
202	new_val = (old_val & ~mask) | (val & mask);
203	change = old_val != new_val;
204	if (change)
205		ret = __aat2870_write(aat2870, addr, new_val);
206
207out_unlock:
208	mutex_unlock(&aat2870->io_lock);
209
210	return ret;
211}
212
213static inline void aat2870_enable(struct aat2870_data *aat2870)
214{
215	if (aat2870->en_pin >= 0)
216		gpio_set_value(aat2870->en_pin, 1);
217
218	aat2870->is_enable = 1;
219}
220
221static inline void aat2870_disable(struct aat2870_data *aat2870)
222{
223	if (aat2870->en_pin >= 0)
224		gpio_set_value(aat2870->en_pin, 0);
225
226	aat2870->is_enable = 0;
227}
228
229#ifdef CONFIG_DEBUG_FS
230static ssize_t aat2870_dump_reg(struct aat2870_data *aat2870, char *buf)
231{
232	u8 addr, val;
233	ssize_t count = 0;
234	int ret;
235
236	count += sprintf(buf, "aat2870 registers\n");
237	for (addr = 0; addr < AAT2870_REG_NUM; addr++) {
238		count += sprintf(buf + count, "0x%02x: ", addr);
239		if (count >= PAGE_SIZE - 1)
240			break;
241
242		ret = aat2870->read(aat2870, addr, &val);
243		if (ret == 0)
244			count += snprintf(buf + count, PAGE_SIZE - count,
245					  "0x%02x", val);
246		else
247			count += snprintf(buf + count, PAGE_SIZE - count,
248					  "<read fail: %d>", ret);
249
250		if (count >= PAGE_SIZE - 1)
251			break;
252
253		count += snprintf(buf + count, PAGE_SIZE - count, "\n");
254		if (count >= PAGE_SIZE - 1)
255			break;
256	}
257
258	/* Truncate count; min() would cause a warning */
259	if (count >= PAGE_SIZE)
260		count = PAGE_SIZE - 1;
261
262	return count;
263}
264
265static int aat2870_reg_open_file(struct inode *inode, struct file *file)
266{
267	file->private_data = inode->i_private;
268
269	return 0;
270}
271
272static ssize_t aat2870_reg_read_file(struct file *file, char __user *user_buf,
273				     size_t count, loff_t *ppos)
274{
275	struct aat2870_data *aat2870 = file->private_data;
276	char *buf;
277	ssize_t ret;
278
279	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
280	if (!buf)
281		return -ENOMEM;
282
283	ret = aat2870_dump_reg(aat2870, buf);
284	if (ret >= 0)
285		ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
286
287	kfree(buf);
288
289	return ret;
290}
291
292static ssize_t aat2870_reg_write_file(struct file *file,
293				      const char __user *user_buf, size_t count,
294				      loff_t *ppos)
295{
296	struct aat2870_data *aat2870 = file->private_data;
297	char buf[32];
298	ssize_t buf_size;
299	char *start = buf;
300	unsigned long addr, val;
301	int ret;
302
303	buf_size = min(count, (sizeof(buf)-1));
304	if (copy_from_user(buf, user_buf, buf_size)) {
305		dev_err(aat2870->dev, "Failed to copy from user\n");
306		return -EFAULT;
307	}
308	buf[buf_size] = 0;
309
310	while (*start == ' ')
311		start++;
312
313	addr = simple_strtoul(start, &start, 16);
314	if (addr >= AAT2870_REG_NUM) {
315		dev_err(aat2870->dev, "Invalid address, 0x%lx\n", addr);
316		return -EINVAL;
317	}
318
319	while (*start == ' ')
320		start++;
321
322	if (strict_strtoul(start, 16, &val))
323		return -EINVAL;
324
325	ret = aat2870->write(aat2870, (u8)addr, (u8)val);
326	if (ret)
327		return ret;
328
329	return buf_size;
330}
331
332static const struct file_operations aat2870_reg_fops = {
333	.open = aat2870_reg_open_file,
334	.read = aat2870_reg_read_file,
335	.write = aat2870_reg_write_file,
336};
337
338static void aat2870_init_debugfs(struct aat2870_data *aat2870)
339{
340	aat2870->dentry_root = debugfs_create_dir("aat2870", NULL);
341	if (!aat2870->dentry_root) {
342		dev_warn(aat2870->dev,
343			 "Failed to create debugfs root directory\n");
344		return;
345	}
346
347	aat2870->dentry_reg = debugfs_create_file("regs", 0644,
348						  aat2870->dentry_root,
349						  aat2870, &aat2870_reg_fops);
350	if (!aat2870->dentry_reg)
351		dev_warn(aat2870->dev,
352			 "Failed to create debugfs register file\n");
353}
354
355static void aat2870_uninit_debugfs(struct aat2870_data *aat2870)
356{
357	debugfs_remove_recursive(aat2870->dentry_root);
358}
359#else
360static inline void aat2870_init_debugfs(struct aat2870_data *aat2870)
361{
362}
363
364static inline void aat2870_uninit_debugfs(struct aat2870_data *aat2870)
365{
366}
367#endif /* CONFIG_DEBUG_FS */
368
369static int aat2870_i2c_probe(struct i2c_client *client,
370			     const struct i2c_device_id *id)
371{
372	struct aat2870_platform_data *pdata = client->dev.platform_data;
373	struct aat2870_data *aat2870;
374	int i, j;
375	int ret = 0;
376
377	aat2870 = kzalloc(sizeof(struct aat2870_data), GFP_KERNEL);
378	if (!aat2870) {
379		dev_err(&client->dev,
380			"Failed to allocate memory for aat2870\n");
381		ret = -ENOMEM;
382		goto out;
383	}
384
385	aat2870->dev = &client->dev;
386	dev_set_drvdata(aat2870->dev, aat2870);
387
388	aat2870->client = client;
389	i2c_set_clientdata(client, aat2870);
390
391	aat2870->reg_cache = aat2870_regs;
392
393	if (pdata->en_pin < 0)
394		aat2870->en_pin = -1;
395	else
396		aat2870->en_pin = pdata->en_pin;
397
398	aat2870->init = pdata->init;
399	aat2870->uninit = pdata->uninit;
400	aat2870->read = aat2870_read;
401	aat2870->write = aat2870_write;
402	aat2870->update = aat2870_update;
403
404	mutex_init(&aat2870->io_lock);
405
406	if (aat2870->init)
407		aat2870->init(aat2870);
408
409	if (aat2870->en_pin >= 0) {
410		ret = gpio_request_one(aat2870->en_pin, GPIOF_OUT_INIT_HIGH,
411				       "aat2870-en");
412		if (ret < 0) {
413			dev_err(&client->dev,
414				"Failed to request GPIO %d\n", aat2870->en_pin);
415			goto out_kfree;
416		}
417	}
418
419	aat2870_enable(aat2870);
420
421	for (i = 0; i < pdata->num_subdevs; i++) {
422		for (j = 0; j < ARRAY_SIZE(aat2870_devs); j++) {
423			if ((pdata->subdevs[i].id == aat2870_devs[j].id) &&
424					!strcmp(pdata->subdevs[i].name,
425						aat2870_devs[j].name)) {
426				aat2870_devs[j].platform_data =
427					pdata->subdevs[i].platform_data;
428				break;
429			}
430		}
431	}
432
433	ret = mfd_add_devices(aat2870->dev, 0, aat2870_devs,
434			      ARRAY_SIZE(aat2870_devs), NULL, 0);
435	if (ret != 0) {
436		dev_err(aat2870->dev, "Failed to add subdev: %d\n", ret);
437		goto out_disable;
438	}
439
440	aat2870_init_debugfs(aat2870);
441
442	return 0;
443
444out_disable:
445	aat2870_disable(aat2870);
446	if (aat2870->en_pin >= 0)
447		gpio_free(aat2870->en_pin);
448out_kfree:
449	kfree(aat2870);
450out:
451	return ret;
452}
453
454static int aat2870_i2c_remove(struct i2c_client *client)
455{
456	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
457
458	aat2870_uninit_debugfs(aat2870);
459
460	mfd_remove_devices(aat2870->dev);
461	aat2870_disable(aat2870);
462	if (aat2870->en_pin >= 0)
463		gpio_free(aat2870->en_pin);
464	if (aat2870->uninit)
465		aat2870->uninit(aat2870);
466	kfree(aat2870);
467
468	return 0;
469}
470
471#ifdef CONFIG_PM_SLEEP
472static int aat2870_i2c_suspend(struct device *dev)
473{
474	struct i2c_client *client = to_i2c_client(dev);
475	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
476
477	aat2870_disable(aat2870);
478
479	return 0;
480}
481
482static int aat2870_i2c_resume(struct device *dev)
483{
484	struct i2c_client *client = to_i2c_client(dev);
485	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
486	struct aat2870_register *reg = NULL;
487	int i;
488
489	aat2870_enable(aat2870);
490
491	/* restore registers */
492	for (i = 0; i < AAT2870_REG_NUM; i++) {
493		reg = &aat2870->reg_cache[i];
494		if (reg->writeable)
495			aat2870->write(aat2870, i, reg->value);
496	}
497
498	return 0;
499}
500#endif /* CONFIG_PM_SLEEP */
501
502static SIMPLE_DEV_PM_OPS(aat2870_pm_ops, aat2870_i2c_suspend,
503			 aat2870_i2c_resume);
504
505static const struct i2c_device_id aat2870_i2c_id_table[] = {
506	{ "aat2870", 0 },
507	{ }
508};
509MODULE_DEVICE_TABLE(i2c, aat2870_i2c_id_table);
510
511static struct i2c_driver aat2870_i2c_driver = {
512	.driver = {
513		.name	= "aat2870",
514		.owner	= THIS_MODULE,
515		.pm	= &aat2870_pm_ops,
516	},
517	.probe		= aat2870_i2c_probe,
518	.remove		= aat2870_i2c_remove,
519	.id_table	= aat2870_i2c_id_table,
520};
521
522static int __init aat2870_init(void)
523{
524	return i2c_add_driver(&aat2870_i2c_driver);
525}
526subsys_initcall(aat2870_init);
527
528static void __exit aat2870_exit(void)
529{
530	i2c_del_driver(&aat2870_i2c_driver);
531}
532module_exit(aat2870_exit);
533
534MODULE_DESCRIPTION("Core support for the AnalogicTech AAT2870");
535MODULE_LICENSE("GPL");
536MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>");
537