xref: /openbmc/linux/drivers/mfd/aat2870-core.c (revision 8fdff1dc)
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 
35 static 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 
78 static 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 
106 static 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 
132 out:
133 	dev_dbg(aat2870->dev, "read: addr=0x%02x, val=0x%02x\n", addr, *val);
134 	return 0;
135 }
136 
137 static 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 
167 static 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 
178 static 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 
189 static 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 
207 out_unlock:
208 	mutex_unlock(&aat2870->io_lock);
209 
210 	return ret;
211 }
212 
213 static 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 
221 static 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
230 static 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 
265 static ssize_t aat2870_reg_read_file(struct file *file, char __user *user_buf,
266 				     size_t count, loff_t *ppos)
267 {
268 	struct aat2870_data *aat2870 = file->private_data;
269 	char *buf;
270 	ssize_t ret;
271 
272 	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
273 	if (!buf)
274 		return -ENOMEM;
275 
276 	ret = aat2870_dump_reg(aat2870, buf);
277 	if (ret >= 0)
278 		ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
279 
280 	kfree(buf);
281 
282 	return ret;
283 }
284 
285 static ssize_t aat2870_reg_write_file(struct file *file,
286 				      const char __user *user_buf, size_t count,
287 				      loff_t *ppos)
288 {
289 	struct aat2870_data *aat2870 = file->private_data;
290 	char buf[32];
291 	ssize_t buf_size;
292 	char *start = buf;
293 	unsigned long addr, val;
294 	int ret;
295 
296 	buf_size = min(count, (sizeof(buf)-1));
297 	if (copy_from_user(buf, user_buf, buf_size)) {
298 		dev_err(aat2870->dev, "Failed to copy from user\n");
299 		return -EFAULT;
300 	}
301 	buf[buf_size] = 0;
302 
303 	while (*start == ' ')
304 		start++;
305 
306 	addr = simple_strtoul(start, &start, 16);
307 	if (addr >= AAT2870_REG_NUM) {
308 		dev_err(aat2870->dev, "Invalid address, 0x%lx\n", addr);
309 		return -EINVAL;
310 	}
311 
312 	while (*start == ' ')
313 		start++;
314 
315 	if (strict_strtoul(start, 16, &val))
316 		return -EINVAL;
317 
318 	ret = aat2870->write(aat2870, (u8)addr, (u8)val);
319 	if (ret)
320 		return ret;
321 
322 	return buf_size;
323 }
324 
325 static const struct file_operations aat2870_reg_fops = {
326 	.open = simple_open,
327 	.read = aat2870_reg_read_file,
328 	.write = aat2870_reg_write_file,
329 };
330 
331 static void aat2870_init_debugfs(struct aat2870_data *aat2870)
332 {
333 	aat2870->dentry_root = debugfs_create_dir("aat2870", NULL);
334 	if (!aat2870->dentry_root) {
335 		dev_warn(aat2870->dev,
336 			 "Failed to create debugfs root directory\n");
337 		return;
338 	}
339 
340 	aat2870->dentry_reg = debugfs_create_file("regs", 0644,
341 						  aat2870->dentry_root,
342 						  aat2870, &aat2870_reg_fops);
343 	if (!aat2870->dentry_reg)
344 		dev_warn(aat2870->dev,
345 			 "Failed to create debugfs register file\n");
346 }
347 
348 static void aat2870_uninit_debugfs(struct aat2870_data *aat2870)
349 {
350 	debugfs_remove_recursive(aat2870->dentry_root);
351 }
352 #else
353 static inline void aat2870_init_debugfs(struct aat2870_data *aat2870)
354 {
355 }
356 
357 static inline void aat2870_uninit_debugfs(struct aat2870_data *aat2870)
358 {
359 }
360 #endif /* CONFIG_DEBUG_FS */
361 
362 static int aat2870_i2c_probe(struct i2c_client *client,
363 			     const struct i2c_device_id *id)
364 {
365 	struct aat2870_platform_data *pdata = client->dev.platform_data;
366 	struct aat2870_data *aat2870;
367 	int i, j;
368 	int ret = 0;
369 
370 	aat2870 = kzalloc(sizeof(struct aat2870_data), GFP_KERNEL);
371 	if (!aat2870) {
372 		dev_err(&client->dev,
373 			"Failed to allocate memory for aat2870\n");
374 		ret = -ENOMEM;
375 		goto out;
376 	}
377 
378 	aat2870->dev = &client->dev;
379 	dev_set_drvdata(aat2870->dev, aat2870);
380 
381 	aat2870->client = client;
382 	i2c_set_clientdata(client, aat2870);
383 
384 	aat2870->reg_cache = aat2870_regs;
385 
386 	if (pdata->en_pin < 0)
387 		aat2870->en_pin = -1;
388 	else
389 		aat2870->en_pin = pdata->en_pin;
390 
391 	aat2870->init = pdata->init;
392 	aat2870->uninit = pdata->uninit;
393 	aat2870->read = aat2870_read;
394 	aat2870->write = aat2870_write;
395 	aat2870->update = aat2870_update;
396 
397 	mutex_init(&aat2870->io_lock);
398 
399 	if (aat2870->init)
400 		aat2870->init(aat2870);
401 
402 	if (aat2870->en_pin >= 0) {
403 		ret = gpio_request_one(aat2870->en_pin, GPIOF_OUT_INIT_HIGH,
404 				       "aat2870-en");
405 		if (ret < 0) {
406 			dev_err(&client->dev,
407 				"Failed to request GPIO %d\n", aat2870->en_pin);
408 			goto out_kfree;
409 		}
410 	}
411 
412 	aat2870_enable(aat2870);
413 
414 	for (i = 0; i < pdata->num_subdevs; i++) {
415 		for (j = 0; j < ARRAY_SIZE(aat2870_devs); j++) {
416 			if ((pdata->subdevs[i].id == aat2870_devs[j].id) &&
417 					!strcmp(pdata->subdevs[i].name,
418 						aat2870_devs[j].name)) {
419 				aat2870_devs[j].platform_data =
420 					pdata->subdevs[i].platform_data;
421 				break;
422 			}
423 		}
424 	}
425 
426 	ret = mfd_add_devices(aat2870->dev, 0, aat2870_devs,
427 			      ARRAY_SIZE(aat2870_devs), NULL, 0, NULL);
428 	if (ret != 0) {
429 		dev_err(aat2870->dev, "Failed to add subdev: %d\n", ret);
430 		goto out_disable;
431 	}
432 
433 	aat2870_init_debugfs(aat2870);
434 
435 	return 0;
436 
437 out_disable:
438 	aat2870_disable(aat2870);
439 	if (aat2870->en_pin >= 0)
440 		gpio_free(aat2870->en_pin);
441 out_kfree:
442 	kfree(aat2870);
443 out:
444 	return ret;
445 }
446 
447 static int aat2870_i2c_remove(struct i2c_client *client)
448 {
449 	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
450 
451 	aat2870_uninit_debugfs(aat2870);
452 
453 	mfd_remove_devices(aat2870->dev);
454 	aat2870_disable(aat2870);
455 	if (aat2870->en_pin >= 0)
456 		gpio_free(aat2870->en_pin);
457 	if (aat2870->uninit)
458 		aat2870->uninit(aat2870);
459 	kfree(aat2870);
460 
461 	return 0;
462 }
463 
464 #ifdef CONFIG_PM_SLEEP
465 static int aat2870_i2c_suspend(struct device *dev)
466 {
467 	struct i2c_client *client = to_i2c_client(dev);
468 	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
469 
470 	aat2870_disable(aat2870);
471 
472 	return 0;
473 }
474 
475 static int aat2870_i2c_resume(struct device *dev)
476 {
477 	struct i2c_client *client = to_i2c_client(dev);
478 	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
479 	struct aat2870_register *reg = NULL;
480 	int i;
481 
482 	aat2870_enable(aat2870);
483 
484 	/* restore registers */
485 	for (i = 0; i < AAT2870_REG_NUM; i++) {
486 		reg = &aat2870->reg_cache[i];
487 		if (reg->writeable)
488 			aat2870->write(aat2870, i, reg->value);
489 	}
490 
491 	return 0;
492 }
493 #endif /* CONFIG_PM_SLEEP */
494 
495 static SIMPLE_DEV_PM_OPS(aat2870_pm_ops, aat2870_i2c_suspend,
496 			 aat2870_i2c_resume);
497 
498 static const struct i2c_device_id aat2870_i2c_id_table[] = {
499 	{ "aat2870", 0 },
500 	{ }
501 };
502 MODULE_DEVICE_TABLE(i2c, aat2870_i2c_id_table);
503 
504 static struct i2c_driver aat2870_i2c_driver = {
505 	.driver = {
506 		.name	= "aat2870",
507 		.owner	= THIS_MODULE,
508 		.pm	= &aat2870_pm_ops,
509 	},
510 	.probe		= aat2870_i2c_probe,
511 	.remove		= aat2870_i2c_remove,
512 	.id_table	= aat2870_i2c_id_table,
513 };
514 
515 static int __init aat2870_init(void)
516 {
517 	return i2c_add_driver(&aat2870_i2c_driver);
518 }
519 subsys_initcall(aat2870_init);
520 
521 static void __exit aat2870_exit(void)
522 {
523 	i2c_del_driver(&aat2870_i2c_driver);
524 }
525 module_exit(aat2870_exit);
526 
527 MODULE_DESCRIPTION("Core support for the AnalogicTech AAT2870");
528 MODULE_LICENSE("GPL");
529 MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>");
530