xref: /openbmc/linux/drivers/mfd/aat2870-core.c (revision 7d545e77)
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 
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 
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 
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 
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 
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 
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 
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
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 += sprintf(buf + 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 
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 
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 
321 static void aat2870_init_debugfs(struct aat2870_data *aat2870)
322 {
323 	aat2870->dentry_root = debugfs_create_dir("aat2870", NULL);
324 	if (!aat2870->dentry_root) {
325 		dev_warn(aat2870->dev,
326 			 "Failed to create debugfs root directory\n");
327 		return;
328 	}
329 
330 	aat2870->dentry_reg = debugfs_create_file("regs", 0644,
331 						  aat2870->dentry_root,
332 						  aat2870, &aat2870_reg_fops);
333 	if (!aat2870->dentry_reg)
334 		dev_warn(aat2870->dev,
335 			 "Failed to create debugfs register file\n");
336 }
337 
338 #else
339 static inline void aat2870_init_debugfs(struct aat2870_data *aat2870)
340 {
341 }
342 #endif /* CONFIG_DEBUG_FS */
343 
344 static int aat2870_i2c_probe(struct i2c_client *client,
345 			     const struct i2c_device_id *id)
346 {
347 	struct aat2870_platform_data *pdata = dev_get_platdata(&client->dev);
348 	struct aat2870_data *aat2870;
349 	int i, j;
350 	int ret = 0;
351 
352 	aat2870 = devm_kzalloc(&client->dev, sizeof(struct aat2870_data),
353 				GFP_KERNEL);
354 	if (!aat2870)
355 		return -ENOMEM;
356 
357 	aat2870->dev = &client->dev;
358 	dev_set_drvdata(aat2870->dev, aat2870);
359 
360 	aat2870->client = client;
361 	i2c_set_clientdata(client, aat2870);
362 
363 	aat2870->reg_cache = aat2870_regs;
364 
365 	if (pdata->en_pin < 0)
366 		aat2870->en_pin = -1;
367 	else
368 		aat2870->en_pin = pdata->en_pin;
369 
370 	aat2870->init = pdata->init;
371 	aat2870->uninit = pdata->uninit;
372 	aat2870->read = aat2870_read;
373 	aat2870->write = aat2870_write;
374 	aat2870->update = aat2870_update;
375 
376 	mutex_init(&aat2870->io_lock);
377 
378 	if (aat2870->init)
379 		aat2870->init(aat2870);
380 
381 	if (aat2870->en_pin >= 0) {
382 		ret = devm_gpio_request_one(&client->dev, aat2870->en_pin,
383 					GPIOF_OUT_INIT_HIGH, "aat2870-en");
384 		if (ret < 0) {
385 			dev_err(&client->dev,
386 				"Failed to request GPIO %d\n", aat2870->en_pin);
387 			return ret;
388 		}
389 	}
390 
391 	aat2870_enable(aat2870);
392 
393 	for (i = 0; i < pdata->num_subdevs; i++) {
394 		for (j = 0; j < ARRAY_SIZE(aat2870_devs); j++) {
395 			if ((pdata->subdevs[i].id == aat2870_devs[j].id) &&
396 					!strcmp(pdata->subdevs[i].name,
397 						aat2870_devs[j].name)) {
398 				aat2870_devs[j].platform_data =
399 					pdata->subdevs[i].platform_data;
400 				break;
401 			}
402 		}
403 	}
404 
405 	ret = mfd_add_devices(aat2870->dev, 0, aat2870_devs,
406 			      ARRAY_SIZE(aat2870_devs), NULL, 0, NULL);
407 	if (ret != 0) {
408 		dev_err(aat2870->dev, "Failed to add subdev: %d\n", ret);
409 		goto out_disable;
410 	}
411 
412 	aat2870_init_debugfs(aat2870);
413 
414 	return 0;
415 
416 out_disable:
417 	aat2870_disable(aat2870);
418 	return ret;
419 }
420 
421 #ifdef CONFIG_PM_SLEEP
422 static int aat2870_i2c_suspend(struct device *dev)
423 {
424 	struct i2c_client *client = to_i2c_client(dev);
425 	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
426 
427 	aat2870_disable(aat2870);
428 
429 	return 0;
430 }
431 
432 static int aat2870_i2c_resume(struct device *dev)
433 {
434 	struct i2c_client *client = to_i2c_client(dev);
435 	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
436 	struct aat2870_register *reg = NULL;
437 	int i;
438 
439 	aat2870_enable(aat2870);
440 
441 	/* restore registers */
442 	for (i = 0; i < AAT2870_REG_NUM; i++) {
443 		reg = &aat2870->reg_cache[i];
444 		if (reg->writeable)
445 			aat2870->write(aat2870, i, reg->value);
446 	}
447 
448 	return 0;
449 }
450 #endif /* CONFIG_PM_SLEEP */
451 
452 static SIMPLE_DEV_PM_OPS(aat2870_pm_ops, aat2870_i2c_suspend,
453 			 aat2870_i2c_resume);
454 
455 static const struct i2c_device_id aat2870_i2c_id_table[] = {
456 	{ "aat2870", 0 },
457 	{ }
458 };
459 
460 static struct i2c_driver aat2870_i2c_driver = {
461 	.driver = {
462 		.name			= "aat2870",
463 		.pm			= &aat2870_pm_ops,
464 		.suppress_bind_attrs	= true,
465 	},
466 	.probe		= aat2870_i2c_probe,
467 	.id_table	= aat2870_i2c_id_table,
468 };
469 
470 static int __init aat2870_init(void)
471 {
472 	return i2c_add_driver(&aat2870_i2c_driver);
473 }
474 subsys_initcall(aat2870_init);
475