1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/drivers/mfd/aat2870-core.c
4 *
5 * Copyright (c) 2011, NVIDIA Corporation.
6 * Author: Jin Park <jinyoungp@nvidia.com>
7 */
8
9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/debugfs.h>
12#include <linux/slab.h>
13#include <linux/uaccess.h>
14#include <linux/i2c.h>
15#include <linux/delay.h>
16#include <linux/gpio.h>
17#include <linux/mfd/core.h>
18#include <linux/mfd/aat2870.h>
19#include <linux/regulator/machine.h>
20
21static struct aat2870_register aat2870_regs[AAT2870_REG_NUM] = {
22	/* readable, writeable, value */
23	{ 0, 1, 0x00 },	/* 0x00 AAT2870_BL_CH_EN */
24	{ 0, 1, 0x16 },	/* 0x01 AAT2870_BLM */
25	{ 0, 1, 0x16 },	/* 0x02 AAT2870_BLS */
26	{ 0, 1, 0x56 },	/* 0x03 AAT2870_BL1 */
27	{ 0, 1, 0x56 },	/* 0x04 AAT2870_BL2 */
28	{ 0, 1, 0x56 },	/* 0x05 AAT2870_BL3 */
29	{ 0, 1, 0x56 },	/* 0x06 AAT2870_BL4 */
30	{ 0, 1, 0x56 },	/* 0x07 AAT2870_BL5 */
31	{ 0, 1, 0x56 },	/* 0x08 AAT2870_BL6 */
32	{ 0, 1, 0x56 },	/* 0x09 AAT2870_BL7 */
33	{ 0, 1, 0x56 },	/* 0x0A AAT2870_BL8 */
34	{ 0, 1, 0x00 },	/* 0x0B AAT2870_FLR */
35	{ 0, 1, 0x03 },	/* 0x0C AAT2870_FM */
36	{ 0, 1, 0x03 },	/* 0x0D AAT2870_FS */
37	{ 0, 1, 0x10 },	/* 0x0E AAT2870_ALS_CFG0 */
38	{ 0, 1, 0x06 },	/* 0x0F AAT2870_ALS_CFG1 */
39	{ 0, 1, 0x00 },	/* 0x10 AAT2870_ALS_CFG2 */
40	{ 1, 0, 0x00 },	/* 0x11 AAT2870_AMB */
41	{ 0, 1, 0x00 },	/* 0x12 AAT2870_ALS0 */
42	{ 0, 1, 0x00 },	/* 0x13 AAT2870_ALS1 */
43	{ 0, 1, 0x00 },	/* 0x14 AAT2870_ALS2 */
44	{ 0, 1, 0x00 },	/* 0x15 AAT2870_ALS3 */
45	{ 0, 1, 0x00 },	/* 0x16 AAT2870_ALS4 */
46	{ 0, 1, 0x00 },	/* 0x17 AAT2870_ALS5 */
47	{ 0, 1, 0x00 },	/* 0x18 AAT2870_ALS6 */
48	{ 0, 1, 0x00 },	/* 0x19 AAT2870_ALS7 */
49	{ 0, 1, 0x00 },	/* 0x1A AAT2870_ALS8 */
50	{ 0, 1, 0x00 },	/* 0x1B AAT2870_ALS9 */
51	{ 0, 1, 0x00 },	/* 0x1C AAT2870_ALSA */
52	{ 0, 1, 0x00 },	/* 0x1D AAT2870_ALSB */
53	{ 0, 1, 0x00 },	/* 0x1E AAT2870_ALSC */
54	{ 0, 1, 0x00 },	/* 0x1F AAT2870_ALSD */
55	{ 0, 1, 0x00 },	/* 0x20 AAT2870_ALSE */
56	{ 0, 1, 0x00 },	/* 0x21 AAT2870_ALSF */
57	{ 0, 1, 0x00 },	/* 0x22 AAT2870_SUB_SET */
58	{ 0, 1, 0x00 },	/* 0x23 AAT2870_SUB_CTRL */
59	{ 0, 1, 0x00 },	/* 0x24 AAT2870_LDO_AB */
60	{ 0, 1, 0x00 },	/* 0x25 AAT2870_LDO_CD */
61	{ 0, 1, 0x00 },	/* 0x26 AAT2870_LDO_EN */
62};
63
64static struct mfd_cell aat2870_devs[] = {
65	{
66		.name = "aat2870-backlight",
67		.id = AAT2870_ID_BL,
68		.pdata_size = sizeof(struct aat2870_bl_platform_data),
69	},
70	{
71		.name = "aat2870-regulator",
72		.id = AAT2870_ID_LDOA,
73		.pdata_size = sizeof(struct regulator_init_data),
74	},
75	{
76		.name = "aat2870-regulator",
77		.id = AAT2870_ID_LDOB,
78		.pdata_size = sizeof(struct regulator_init_data),
79	},
80	{
81		.name = "aat2870-regulator",
82		.id = AAT2870_ID_LDOC,
83		.pdata_size = sizeof(struct regulator_init_data),
84	},
85	{
86		.name = "aat2870-regulator",
87		.id = AAT2870_ID_LDOD,
88		.pdata_size = sizeof(struct regulator_init_data),
89	},
90};
91
92static int __aat2870_read(struct aat2870_data *aat2870, u8 addr, u8 *val)
93{
94	int ret;
95
96	if (addr >= AAT2870_REG_NUM) {
97		dev_err(aat2870->dev, "Invalid address, 0x%02x\n", addr);
98		return -EINVAL;
99	}
100
101	if (!aat2870->reg_cache[addr].readable) {
102		*val = aat2870->reg_cache[addr].value;
103		goto out;
104	}
105
106	ret = i2c_master_send(aat2870->client, &addr, 1);
107	if (ret < 0)
108		return ret;
109	if (ret != 1)
110		return -EIO;
111
112	ret = i2c_master_recv(aat2870->client, val, 1);
113	if (ret < 0)
114		return ret;
115	if (ret != 1)
116		return -EIO;
117
118out:
119	dev_dbg(aat2870->dev, "read: addr=0x%02x, val=0x%02x\n", addr, *val);
120	return 0;
121}
122
123static int __aat2870_write(struct aat2870_data *aat2870, u8 addr, u8 val)
124{
125	u8 msg[2];
126	int ret;
127
128	if (addr >= AAT2870_REG_NUM) {
129		dev_err(aat2870->dev, "Invalid address, 0x%02x\n", addr);
130		return -EINVAL;
131	}
132
133	if (!aat2870->reg_cache[addr].writeable) {
134		dev_err(aat2870->dev, "Address 0x%02x is not writeable\n",
135			addr);
136		return -EINVAL;
137	}
138
139	msg[0] = addr;
140	msg[1] = val;
141	ret = i2c_master_send(aat2870->client, msg, 2);
142	if (ret < 0)
143		return ret;
144	if (ret != 2)
145		return -EIO;
146
147	aat2870->reg_cache[addr].value = val;
148
149	dev_dbg(aat2870->dev, "write: addr=0x%02x, val=0x%02x\n", addr, val);
150	return 0;
151}
152
153static int aat2870_read(struct aat2870_data *aat2870, u8 addr, u8 *val)
154{
155	int ret;
156
157	mutex_lock(&aat2870->io_lock);
158	ret = __aat2870_read(aat2870, addr, val);
159	mutex_unlock(&aat2870->io_lock);
160
161	return ret;
162}
163
164static int aat2870_write(struct aat2870_data *aat2870, u8 addr, u8 val)
165{
166	int ret;
167
168	mutex_lock(&aat2870->io_lock);
169	ret = __aat2870_write(aat2870, addr, val);
170	mutex_unlock(&aat2870->io_lock);
171
172	return ret;
173}
174
175static int aat2870_update(struct aat2870_data *aat2870, u8 addr, u8 mask,
176			  u8 val)
177{
178	int change;
179	u8 old_val, new_val;
180	int ret;
181
182	mutex_lock(&aat2870->io_lock);
183
184	ret = __aat2870_read(aat2870, addr, &old_val);
185	if (ret)
186		goto out_unlock;
187
188	new_val = (old_val & ~mask) | (val & mask);
189	change = old_val != new_val;
190	if (change)
191		ret = __aat2870_write(aat2870, addr, new_val);
192
193out_unlock:
194	mutex_unlock(&aat2870->io_lock);
195
196	return ret;
197}
198
199static inline void aat2870_enable(struct aat2870_data *aat2870)
200{
201	if (aat2870->en_pin >= 0)
202		gpio_set_value(aat2870->en_pin, 1);
203
204	aat2870->is_enable = 1;
205}
206
207static inline void aat2870_disable(struct aat2870_data *aat2870)
208{
209	if (aat2870->en_pin >= 0)
210		gpio_set_value(aat2870->en_pin, 0);
211
212	aat2870->is_enable = 0;
213}
214
215#ifdef CONFIG_DEBUG_FS
216static ssize_t aat2870_dump_reg(struct aat2870_data *aat2870, char *buf)
217{
218	u8 addr, val;
219	ssize_t count = 0;
220	int ret;
221
222	count += sprintf(buf, "aat2870 registers\n");
223	for (addr = 0; addr < AAT2870_REG_NUM; addr++) {
224		count += snprintf(buf + count, PAGE_SIZE - count, "0x%02x: ", addr);
225		if (count >= PAGE_SIZE - 1)
226			break;
227
228		ret = aat2870->read(aat2870, addr, &val);
229		if (ret == 0)
230			count += snprintf(buf + count, PAGE_SIZE - count,
231					  "0x%02x", val);
232		else
233			count += snprintf(buf + count, PAGE_SIZE - count,
234					  "<read fail: %d>", ret);
235
236		if (count >= PAGE_SIZE - 1)
237			break;
238
239		count += snprintf(buf + count, PAGE_SIZE - count, "\n");
240		if (count >= PAGE_SIZE - 1)
241			break;
242	}
243
244	/* Truncate count; min() would cause a warning */
245	if (count >= PAGE_SIZE)
246		count = PAGE_SIZE - 1;
247
248	return count;
249}
250
251static ssize_t aat2870_reg_read_file(struct file *file, char __user *user_buf,
252				     size_t count, loff_t *ppos)
253{
254	struct aat2870_data *aat2870 = file->private_data;
255	char *buf;
256	ssize_t ret;
257
258	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
259	if (!buf)
260		return -ENOMEM;
261
262	ret = aat2870_dump_reg(aat2870, buf);
263	if (ret >= 0)
264		ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
265
266	kfree(buf);
267
268	return ret;
269}
270
271static ssize_t aat2870_reg_write_file(struct file *file,
272				      const char __user *user_buf, size_t count,
273				      loff_t *ppos)
274{
275	struct aat2870_data *aat2870 = file->private_data;
276	char buf[32];
277	ssize_t buf_size;
278	char *start = buf;
279	unsigned long addr, val;
280	int ret;
281
282	buf_size = min(count, (size_t)(sizeof(buf)-1));
283	if (copy_from_user(buf, user_buf, buf_size)) {
284		dev_err(aat2870->dev, "Failed to copy from user\n");
285		return -EFAULT;
286	}
287	buf[buf_size] = 0;
288
289	while (*start == ' ')
290		start++;
291
292	ret = kstrtoul(start, 16, &addr);
293	if (ret)
294		return ret;
295
296	if (addr >= AAT2870_REG_NUM) {
297		dev_err(aat2870->dev, "Invalid address, 0x%lx\n", addr);
298		return -EINVAL;
299	}
300
301	while (*start == ' ')
302		start++;
303
304	ret = kstrtoul(start, 16, &val);
305	if (ret)
306		return ret;
307
308	ret = aat2870->write(aat2870, (u8)addr, (u8)val);
309	if (ret)
310		return ret;
311
312	return buf_size;
313}
314
315static const struct file_operations aat2870_reg_fops = {
316	.open = simple_open,
317	.read = aat2870_reg_read_file,
318	.write = aat2870_reg_write_file,
319};
320
321static void aat2870_init_debugfs(struct aat2870_data *aat2870)
322{
323	aat2870->dentry_root = debugfs_create_dir("aat2870", NULL);
324
325	debugfs_create_file("regs", 0644, aat2870->dentry_root, aat2870,
326			    &aat2870_reg_fops);
327}
328
329#else
330static inline void aat2870_init_debugfs(struct aat2870_data *aat2870)
331{
332}
333#endif /* CONFIG_DEBUG_FS */
334
335static int aat2870_i2c_probe(struct i2c_client *client)
336{
337	struct aat2870_platform_data *pdata = dev_get_platdata(&client->dev);
338	struct aat2870_data *aat2870;
339	int i, j;
340	int ret = 0;
341
342	aat2870 = devm_kzalloc(&client->dev, sizeof(struct aat2870_data),
343				GFP_KERNEL);
344	if (!aat2870)
345		return -ENOMEM;
346
347	aat2870->dev = &client->dev;
348	aat2870->client = client;
349	i2c_set_clientdata(client, aat2870);
350
351	aat2870->reg_cache = aat2870_regs;
352
353	if (pdata->en_pin < 0)
354		aat2870->en_pin = -1;
355	else
356		aat2870->en_pin = pdata->en_pin;
357
358	aat2870->init = pdata->init;
359	aat2870->uninit = pdata->uninit;
360	aat2870->read = aat2870_read;
361	aat2870->write = aat2870_write;
362	aat2870->update = aat2870_update;
363
364	mutex_init(&aat2870->io_lock);
365
366	if (aat2870->init)
367		aat2870->init(aat2870);
368
369	if (aat2870->en_pin >= 0) {
370		ret = devm_gpio_request_one(&client->dev, aat2870->en_pin,
371					GPIOF_OUT_INIT_HIGH, "aat2870-en");
372		if (ret < 0) {
373			dev_err(&client->dev,
374				"Failed to request GPIO %d\n", aat2870->en_pin);
375			return ret;
376		}
377	}
378
379	aat2870_enable(aat2870);
380
381	for (i = 0; i < pdata->num_subdevs; i++) {
382		for (j = 0; j < ARRAY_SIZE(aat2870_devs); j++) {
383			if ((pdata->subdevs[i].id == aat2870_devs[j].id) &&
384					!strcmp(pdata->subdevs[i].name,
385						aat2870_devs[j].name)) {
386				aat2870_devs[j].platform_data =
387					pdata->subdevs[i].platform_data;
388				break;
389			}
390		}
391	}
392
393	ret = mfd_add_devices(aat2870->dev, 0, aat2870_devs,
394			      ARRAY_SIZE(aat2870_devs), NULL, 0, NULL);
395	if (ret != 0) {
396		dev_err(aat2870->dev, "Failed to add subdev: %d\n", ret);
397		goto out_disable;
398	}
399
400	aat2870_init_debugfs(aat2870);
401
402	return 0;
403
404out_disable:
405	aat2870_disable(aat2870);
406	return ret;
407}
408
409static int aat2870_i2c_suspend(struct device *dev)
410{
411	struct i2c_client *client = to_i2c_client(dev);
412	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
413
414	aat2870_disable(aat2870);
415
416	return 0;
417}
418
419static int aat2870_i2c_resume(struct device *dev)
420{
421	struct i2c_client *client = to_i2c_client(dev);
422	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
423	struct aat2870_register *reg = NULL;
424	int i;
425
426	aat2870_enable(aat2870);
427
428	/* restore registers */
429	for (i = 0; i < AAT2870_REG_NUM; i++) {
430		reg = &aat2870->reg_cache[i];
431		if (reg->writeable)
432			aat2870->write(aat2870, i, reg->value);
433	}
434
435	return 0;
436}
437
438static DEFINE_SIMPLE_DEV_PM_OPS(aat2870_pm_ops, aat2870_i2c_suspend,
439				aat2870_i2c_resume);
440
441static const struct i2c_device_id aat2870_i2c_id_table[] = {
442	{ "aat2870", 0 },
443	{ }
444};
445
446static struct i2c_driver aat2870_i2c_driver = {
447	.driver = {
448		.name			= "aat2870",
449		.pm			= pm_sleep_ptr(&aat2870_pm_ops),
450		.suppress_bind_attrs	= true,
451	},
452	.probe		= aat2870_i2c_probe,
453	.id_table	= aat2870_i2c_id_table,
454};
455
456static int __init aat2870_init(void)
457{
458	return i2c_add_driver(&aat2870_i2c_driver);
459}
460subsys_initcall(aat2870_init);
461