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 
21 static 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 
64 static 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 
__aat2870_read(struct aat2870_data * aat2870,u8 addr,u8 * val)92 static 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 
118 out:
119 	dev_dbg(aat2870->dev, "read: addr=0x%02x, val=0x%02x\n", addr, *val);
120 	return 0;
121 }
122 
__aat2870_write(struct aat2870_data * aat2870,u8 addr,u8 val)123 static 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 
aat2870_read(struct aat2870_data * aat2870,u8 addr,u8 * val)153 static 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 
aat2870_write(struct aat2870_data * aat2870,u8 addr,u8 val)164 static 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 
aat2870_update(struct aat2870_data * aat2870,u8 addr,u8 mask,u8 val)175 static 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 
193 out_unlock:
194 	mutex_unlock(&aat2870->io_lock);
195 
196 	return ret;
197 }
198 
aat2870_enable(struct aat2870_data * aat2870)199 static 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 
aat2870_disable(struct aat2870_data * aat2870)207 static 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
aat2870_dump_reg(struct aat2870_data * aat2870,char * buf)216 static 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 
aat2870_reg_read_file(struct file * file,char __user * user_buf,size_t count,loff_t * ppos)251 static 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 
aat2870_reg_write_file(struct file * file,const char __user * user_buf,size_t count,loff_t * ppos)271 static 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 
315 static 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 
aat2870_init_debugfs(struct aat2870_data * aat2870)321 static 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
aat2870_init_debugfs(struct aat2870_data * aat2870)330 static inline void aat2870_init_debugfs(struct aat2870_data *aat2870)
331 {
332 }
333 #endif /* CONFIG_DEBUG_FS */
334 
aat2870_i2c_probe(struct i2c_client * client)335 static 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 	dev_set_drvdata(aat2870->dev, aat2870);
349 
350 	aat2870->client = client;
351 	i2c_set_clientdata(client, aat2870);
352 
353 	aat2870->reg_cache = aat2870_regs;
354 
355 	if (pdata->en_pin < 0)
356 		aat2870->en_pin = -1;
357 	else
358 		aat2870->en_pin = pdata->en_pin;
359 
360 	aat2870->init = pdata->init;
361 	aat2870->uninit = pdata->uninit;
362 	aat2870->read = aat2870_read;
363 	aat2870->write = aat2870_write;
364 	aat2870->update = aat2870_update;
365 
366 	mutex_init(&aat2870->io_lock);
367 
368 	if (aat2870->init)
369 		aat2870->init(aat2870);
370 
371 	if (aat2870->en_pin >= 0) {
372 		ret = devm_gpio_request_one(&client->dev, aat2870->en_pin,
373 					GPIOF_OUT_INIT_HIGH, "aat2870-en");
374 		if (ret < 0) {
375 			dev_err(&client->dev,
376 				"Failed to request GPIO %d\n", aat2870->en_pin);
377 			return ret;
378 		}
379 	}
380 
381 	aat2870_enable(aat2870);
382 
383 	for (i = 0; i < pdata->num_subdevs; i++) {
384 		for (j = 0; j < ARRAY_SIZE(aat2870_devs); j++) {
385 			if ((pdata->subdevs[i].id == aat2870_devs[j].id) &&
386 					!strcmp(pdata->subdevs[i].name,
387 						aat2870_devs[j].name)) {
388 				aat2870_devs[j].platform_data =
389 					pdata->subdevs[i].platform_data;
390 				break;
391 			}
392 		}
393 	}
394 
395 	ret = mfd_add_devices(aat2870->dev, 0, aat2870_devs,
396 			      ARRAY_SIZE(aat2870_devs), NULL, 0, NULL);
397 	if (ret != 0) {
398 		dev_err(aat2870->dev, "Failed to add subdev: %d\n", ret);
399 		goto out_disable;
400 	}
401 
402 	aat2870_init_debugfs(aat2870);
403 
404 	return 0;
405 
406 out_disable:
407 	aat2870_disable(aat2870);
408 	return ret;
409 }
410 
aat2870_i2c_suspend(struct device * dev)411 static int aat2870_i2c_suspend(struct device *dev)
412 {
413 	struct i2c_client *client = to_i2c_client(dev);
414 	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
415 
416 	aat2870_disable(aat2870);
417 
418 	return 0;
419 }
420 
aat2870_i2c_resume(struct device * dev)421 static int aat2870_i2c_resume(struct device *dev)
422 {
423 	struct i2c_client *client = to_i2c_client(dev);
424 	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
425 	struct aat2870_register *reg = NULL;
426 	int i;
427 
428 	aat2870_enable(aat2870);
429 
430 	/* restore registers */
431 	for (i = 0; i < AAT2870_REG_NUM; i++) {
432 		reg = &aat2870->reg_cache[i];
433 		if (reg->writeable)
434 			aat2870->write(aat2870, i, reg->value);
435 	}
436 
437 	return 0;
438 }
439 
440 static DEFINE_SIMPLE_DEV_PM_OPS(aat2870_pm_ops, aat2870_i2c_suspend,
441 				aat2870_i2c_resume);
442 
443 static const struct i2c_device_id aat2870_i2c_id_table[] = {
444 	{ "aat2870", 0 },
445 	{ }
446 };
447 
448 static struct i2c_driver aat2870_i2c_driver = {
449 	.driver = {
450 		.name			= "aat2870",
451 		.pm			= pm_sleep_ptr(&aat2870_pm_ops),
452 		.suppress_bind_attrs	= true,
453 	},
454 	.probe_new	= aat2870_i2c_probe,
455 	.id_table	= aat2870_i2c_id_table,
456 };
457 
aat2870_init(void)458 static int __init aat2870_init(void)
459 {
460 	return i2c_add_driver(&aat2870_i2c_driver);
461 }
462 subsys_initcall(aat2870_init);
463