xref: /openbmc/linux/drivers/mfd/aat2870-core.c (revision ae213c44)
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/init.h>
24 #include <linux/debugfs.h>
25 #include <linux/slab.h>
26 #include <linux/uaccess.h>
27 #include <linux/i2c.h>
28 #include <linux/delay.h>
29 #include <linux/gpio.h>
30 #include <linux/mfd/core.h>
31 #include <linux/mfd/aat2870.h>
32 #include <linux/regulator/machine.h>
33 
34 static struct aat2870_register aat2870_regs[AAT2870_REG_NUM] = {
35 	/* readable, writeable, value */
36 	{ 0, 1, 0x00 },	/* 0x00 AAT2870_BL_CH_EN */
37 	{ 0, 1, 0x16 },	/* 0x01 AAT2870_BLM */
38 	{ 0, 1, 0x16 },	/* 0x02 AAT2870_BLS */
39 	{ 0, 1, 0x56 },	/* 0x03 AAT2870_BL1 */
40 	{ 0, 1, 0x56 },	/* 0x04 AAT2870_BL2 */
41 	{ 0, 1, 0x56 },	/* 0x05 AAT2870_BL3 */
42 	{ 0, 1, 0x56 },	/* 0x06 AAT2870_BL4 */
43 	{ 0, 1, 0x56 },	/* 0x07 AAT2870_BL5 */
44 	{ 0, 1, 0x56 },	/* 0x08 AAT2870_BL6 */
45 	{ 0, 1, 0x56 },	/* 0x09 AAT2870_BL7 */
46 	{ 0, 1, 0x56 },	/* 0x0A AAT2870_BL8 */
47 	{ 0, 1, 0x00 },	/* 0x0B AAT2870_FLR */
48 	{ 0, 1, 0x03 },	/* 0x0C AAT2870_FM */
49 	{ 0, 1, 0x03 },	/* 0x0D AAT2870_FS */
50 	{ 0, 1, 0x10 },	/* 0x0E AAT2870_ALS_CFG0 */
51 	{ 0, 1, 0x06 },	/* 0x0F AAT2870_ALS_CFG1 */
52 	{ 0, 1, 0x00 },	/* 0x10 AAT2870_ALS_CFG2 */
53 	{ 1, 0, 0x00 },	/* 0x11 AAT2870_AMB */
54 	{ 0, 1, 0x00 },	/* 0x12 AAT2870_ALS0 */
55 	{ 0, 1, 0x00 },	/* 0x13 AAT2870_ALS1 */
56 	{ 0, 1, 0x00 },	/* 0x14 AAT2870_ALS2 */
57 	{ 0, 1, 0x00 },	/* 0x15 AAT2870_ALS3 */
58 	{ 0, 1, 0x00 },	/* 0x16 AAT2870_ALS4 */
59 	{ 0, 1, 0x00 },	/* 0x17 AAT2870_ALS5 */
60 	{ 0, 1, 0x00 },	/* 0x18 AAT2870_ALS6 */
61 	{ 0, 1, 0x00 },	/* 0x19 AAT2870_ALS7 */
62 	{ 0, 1, 0x00 },	/* 0x1A AAT2870_ALS8 */
63 	{ 0, 1, 0x00 },	/* 0x1B AAT2870_ALS9 */
64 	{ 0, 1, 0x00 },	/* 0x1C AAT2870_ALSA */
65 	{ 0, 1, 0x00 },	/* 0x1D AAT2870_ALSB */
66 	{ 0, 1, 0x00 },	/* 0x1E AAT2870_ALSC */
67 	{ 0, 1, 0x00 },	/* 0x1F AAT2870_ALSD */
68 	{ 0, 1, 0x00 },	/* 0x20 AAT2870_ALSE */
69 	{ 0, 1, 0x00 },	/* 0x21 AAT2870_ALSF */
70 	{ 0, 1, 0x00 },	/* 0x22 AAT2870_SUB_SET */
71 	{ 0, 1, 0x00 },	/* 0x23 AAT2870_SUB_CTRL */
72 	{ 0, 1, 0x00 },	/* 0x24 AAT2870_LDO_AB */
73 	{ 0, 1, 0x00 },	/* 0x25 AAT2870_LDO_CD */
74 	{ 0, 1, 0x00 },	/* 0x26 AAT2870_LDO_EN */
75 };
76 
77 static struct mfd_cell aat2870_devs[] = {
78 	{
79 		.name = "aat2870-backlight",
80 		.id = AAT2870_ID_BL,
81 		.pdata_size = sizeof(struct aat2870_bl_platform_data),
82 	},
83 	{
84 		.name = "aat2870-regulator",
85 		.id = AAT2870_ID_LDOA,
86 		.pdata_size = sizeof(struct regulator_init_data),
87 	},
88 	{
89 		.name = "aat2870-regulator",
90 		.id = AAT2870_ID_LDOB,
91 		.pdata_size = sizeof(struct regulator_init_data),
92 	},
93 	{
94 		.name = "aat2870-regulator",
95 		.id = AAT2870_ID_LDOC,
96 		.pdata_size = sizeof(struct regulator_init_data),
97 	},
98 	{
99 		.name = "aat2870-regulator",
100 		.id = AAT2870_ID_LDOD,
101 		.pdata_size = sizeof(struct regulator_init_data),
102 	},
103 };
104 
105 static int __aat2870_read(struct aat2870_data *aat2870, u8 addr, u8 *val)
106 {
107 	int ret;
108 
109 	if (addr >= AAT2870_REG_NUM) {
110 		dev_err(aat2870->dev, "Invalid address, 0x%02x\n", addr);
111 		return -EINVAL;
112 	}
113 
114 	if (!aat2870->reg_cache[addr].readable) {
115 		*val = aat2870->reg_cache[addr].value;
116 		goto out;
117 	}
118 
119 	ret = i2c_master_send(aat2870->client, &addr, 1);
120 	if (ret < 0)
121 		return ret;
122 	if (ret != 1)
123 		return -EIO;
124 
125 	ret = i2c_master_recv(aat2870->client, val, 1);
126 	if (ret < 0)
127 		return ret;
128 	if (ret != 1)
129 		return -EIO;
130 
131 out:
132 	dev_dbg(aat2870->dev, "read: addr=0x%02x, val=0x%02x\n", addr, *val);
133 	return 0;
134 }
135 
136 static int __aat2870_write(struct aat2870_data *aat2870, u8 addr, u8 val)
137 {
138 	u8 msg[2];
139 	int ret;
140 
141 	if (addr >= AAT2870_REG_NUM) {
142 		dev_err(aat2870->dev, "Invalid address, 0x%02x\n", addr);
143 		return -EINVAL;
144 	}
145 
146 	if (!aat2870->reg_cache[addr].writeable) {
147 		dev_err(aat2870->dev, "Address 0x%02x is not writeable\n",
148 			addr);
149 		return -EINVAL;
150 	}
151 
152 	msg[0] = addr;
153 	msg[1] = val;
154 	ret = i2c_master_send(aat2870->client, msg, 2);
155 	if (ret < 0)
156 		return ret;
157 	if (ret != 2)
158 		return -EIO;
159 
160 	aat2870->reg_cache[addr].value = val;
161 
162 	dev_dbg(aat2870->dev, "write: addr=0x%02x, val=0x%02x\n", addr, val);
163 	return 0;
164 }
165 
166 static int aat2870_read(struct aat2870_data *aat2870, u8 addr, u8 *val)
167 {
168 	int ret;
169 
170 	mutex_lock(&aat2870->io_lock);
171 	ret = __aat2870_read(aat2870, addr, val);
172 	mutex_unlock(&aat2870->io_lock);
173 
174 	return ret;
175 }
176 
177 static int aat2870_write(struct aat2870_data *aat2870, u8 addr, u8 val)
178 {
179 	int ret;
180 
181 	mutex_lock(&aat2870->io_lock);
182 	ret = __aat2870_write(aat2870, addr, val);
183 	mutex_unlock(&aat2870->io_lock);
184 
185 	return ret;
186 }
187 
188 static int aat2870_update(struct aat2870_data *aat2870, u8 addr, u8 mask,
189 			  u8 val)
190 {
191 	int change;
192 	u8 old_val, new_val;
193 	int ret;
194 
195 	mutex_lock(&aat2870->io_lock);
196 
197 	ret = __aat2870_read(aat2870, addr, &old_val);
198 	if (ret)
199 		goto out_unlock;
200 
201 	new_val = (old_val & ~mask) | (val & mask);
202 	change = old_val != new_val;
203 	if (change)
204 		ret = __aat2870_write(aat2870, addr, new_val);
205 
206 out_unlock:
207 	mutex_unlock(&aat2870->io_lock);
208 
209 	return ret;
210 }
211 
212 static inline void aat2870_enable(struct aat2870_data *aat2870)
213 {
214 	if (aat2870->en_pin >= 0)
215 		gpio_set_value(aat2870->en_pin, 1);
216 
217 	aat2870->is_enable = 1;
218 }
219 
220 static inline void aat2870_disable(struct aat2870_data *aat2870)
221 {
222 	if (aat2870->en_pin >= 0)
223 		gpio_set_value(aat2870->en_pin, 0);
224 
225 	aat2870->is_enable = 0;
226 }
227 
228 #ifdef CONFIG_DEBUG_FS
229 static ssize_t aat2870_dump_reg(struct aat2870_data *aat2870, char *buf)
230 {
231 	u8 addr, val;
232 	ssize_t count = 0;
233 	int ret;
234 
235 	count += sprintf(buf, "aat2870 registers\n");
236 	for (addr = 0; addr < AAT2870_REG_NUM; addr++) {
237 		count += sprintf(buf + count, "0x%02x: ", addr);
238 		if (count >= PAGE_SIZE - 1)
239 			break;
240 
241 		ret = aat2870->read(aat2870, addr, &val);
242 		if (ret == 0)
243 			count += snprintf(buf + count, PAGE_SIZE - count,
244 					  "0x%02x", val);
245 		else
246 			count += snprintf(buf + count, PAGE_SIZE - count,
247 					  "<read fail: %d>", ret);
248 
249 		if (count >= PAGE_SIZE - 1)
250 			break;
251 
252 		count += snprintf(buf + count, PAGE_SIZE - count, "\n");
253 		if (count >= PAGE_SIZE - 1)
254 			break;
255 	}
256 
257 	/* Truncate count; min() would cause a warning */
258 	if (count >= PAGE_SIZE)
259 		count = PAGE_SIZE - 1;
260 
261 	return count;
262 }
263 
264 static ssize_t aat2870_reg_read_file(struct file *file, char __user *user_buf,
265 				     size_t count, loff_t *ppos)
266 {
267 	struct aat2870_data *aat2870 = file->private_data;
268 	char *buf;
269 	ssize_t ret;
270 
271 	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
272 	if (!buf)
273 		return -ENOMEM;
274 
275 	ret = aat2870_dump_reg(aat2870, buf);
276 	if (ret >= 0)
277 		ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
278 
279 	kfree(buf);
280 
281 	return ret;
282 }
283 
284 static ssize_t aat2870_reg_write_file(struct file *file,
285 				      const char __user *user_buf, size_t count,
286 				      loff_t *ppos)
287 {
288 	struct aat2870_data *aat2870 = file->private_data;
289 	char buf[32];
290 	ssize_t buf_size;
291 	char *start = buf;
292 	unsigned long addr, val;
293 	int ret;
294 
295 	buf_size = min(count, (size_t)(sizeof(buf)-1));
296 	if (copy_from_user(buf, user_buf, buf_size)) {
297 		dev_err(aat2870->dev, "Failed to copy from user\n");
298 		return -EFAULT;
299 	}
300 	buf[buf_size] = 0;
301 
302 	while (*start == ' ')
303 		start++;
304 
305 	ret = kstrtoul(start, 16, &addr);
306 	if (ret)
307 		return ret;
308 
309 	if (addr >= AAT2870_REG_NUM) {
310 		dev_err(aat2870->dev, "Invalid address, 0x%lx\n", addr);
311 		return -EINVAL;
312 	}
313 
314 	while (*start == ' ')
315 		start++;
316 
317 	ret = kstrtoul(start, 16, &val);
318 	if (ret)
319 		return ret;
320 
321 	ret = aat2870->write(aat2870, (u8)addr, (u8)val);
322 	if (ret)
323 		return ret;
324 
325 	return buf_size;
326 }
327 
328 static const struct file_operations aat2870_reg_fops = {
329 	.open = simple_open,
330 	.read = aat2870_reg_read_file,
331 	.write = aat2870_reg_write_file,
332 };
333 
334 static void aat2870_init_debugfs(struct aat2870_data *aat2870)
335 {
336 	aat2870->dentry_root = debugfs_create_dir("aat2870", NULL);
337 	if (!aat2870->dentry_root) {
338 		dev_warn(aat2870->dev,
339 			 "Failed to create debugfs root directory\n");
340 		return;
341 	}
342 
343 	aat2870->dentry_reg = debugfs_create_file("regs", 0644,
344 						  aat2870->dentry_root,
345 						  aat2870, &aat2870_reg_fops);
346 	if (!aat2870->dentry_reg)
347 		dev_warn(aat2870->dev,
348 			 "Failed to create debugfs register file\n");
349 }
350 
351 #else
352 static inline void aat2870_init_debugfs(struct aat2870_data *aat2870)
353 {
354 }
355 #endif /* CONFIG_DEBUG_FS */
356 
357 static int aat2870_i2c_probe(struct i2c_client *client,
358 			     const struct i2c_device_id *id)
359 {
360 	struct aat2870_platform_data *pdata = dev_get_platdata(&client->dev);
361 	struct aat2870_data *aat2870;
362 	int i, j;
363 	int ret = 0;
364 
365 	aat2870 = devm_kzalloc(&client->dev, sizeof(struct aat2870_data),
366 				GFP_KERNEL);
367 	if (!aat2870)
368 		return -ENOMEM;
369 
370 	aat2870->dev = &client->dev;
371 	dev_set_drvdata(aat2870->dev, aat2870);
372 
373 	aat2870->client = client;
374 	i2c_set_clientdata(client, aat2870);
375 
376 	aat2870->reg_cache = aat2870_regs;
377 
378 	if (pdata->en_pin < 0)
379 		aat2870->en_pin = -1;
380 	else
381 		aat2870->en_pin = pdata->en_pin;
382 
383 	aat2870->init = pdata->init;
384 	aat2870->uninit = pdata->uninit;
385 	aat2870->read = aat2870_read;
386 	aat2870->write = aat2870_write;
387 	aat2870->update = aat2870_update;
388 
389 	mutex_init(&aat2870->io_lock);
390 
391 	if (aat2870->init)
392 		aat2870->init(aat2870);
393 
394 	if (aat2870->en_pin >= 0) {
395 		ret = devm_gpio_request_one(&client->dev, aat2870->en_pin,
396 					GPIOF_OUT_INIT_HIGH, "aat2870-en");
397 		if (ret < 0) {
398 			dev_err(&client->dev,
399 				"Failed to request GPIO %d\n", aat2870->en_pin);
400 			return ret;
401 		}
402 	}
403 
404 	aat2870_enable(aat2870);
405 
406 	for (i = 0; i < pdata->num_subdevs; i++) {
407 		for (j = 0; j < ARRAY_SIZE(aat2870_devs); j++) {
408 			if ((pdata->subdevs[i].id == aat2870_devs[j].id) &&
409 					!strcmp(pdata->subdevs[i].name,
410 						aat2870_devs[j].name)) {
411 				aat2870_devs[j].platform_data =
412 					pdata->subdevs[i].platform_data;
413 				break;
414 			}
415 		}
416 	}
417 
418 	ret = mfd_add_devices(aat2870->dev, 0, aat2870_devs,
419 			      ARRAY_SIZE(aat2870_devs), NULL, 0, NULL);
420 	if (ret != 0) {
421 		dev_err(aat2870->dev, "Failed to add subdev: %d\n", ret);
422 		goto out_disable;
423 	}
424 
425 	aat2870_init_debugfs(aat2870);
426 
427 	return 0;
428 
429 out_disable:
430 	aat2870_disable(aat2870);
431 	return ret;
432 }
433 
434 #ifdef CONFIG_PM_SLEEP
435 static int aat2870_i2c_suspend(struct device *dev)
436 {
437 	struct i2c_client *client = to_i2c_client(dev);
438 	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
439 
440 	aat2870_disable(aat2870);
441 
442 	return 0;
443 }
444 
445 static int aat2870_i2c_resume(struct device *dev)
446 {
447 	struct i2c_client *client = to_i2c_client(dev);
448 	struct aat2870_data *aat2870 = i2c_get_clientdata(client);
449 	struct aat2870_register *reg = NULL;
450 	int i;
451 
452 	aat2870_enable(aat2870);
453 
454 	/* restore registers */
455 	for (i = 0; i < AAT2870_REG_NUM; i++) {
456 		reg = &aat2870->reg_cache[i];
457 		if (reg->writeable)
458 			aat2870->write(aat2870, i, reg->value);
459 	}
460 
461 	return 0;
462 }
463 #endif /* CONFIG_PM_SLEEP */
464 
465 static SIMPLE_DEV_PM_OPS(aat2870_pm_ops, aat2870_i2c_suspend,
466 			 aat2870_i2c_resume);
467 
468 static const struct i2c_device_id aat2870_i2c_id_table[] = {
469 	{ "aat2870", 0 },
470 	{ }
471 };
472 
473 static struct i2c_driver aat2870_i2c_driver = {
474 	.driver = {
475 		.name			= "aat2870",
476 		.pm			= &aat2870_pm_ops,
477 		.suppress_bind_attrs	= true,
478 	},
479 	.probe		= aat2870_i2c_probe,
480 	.id_table	= aat2870_i2c_id_table,
481 };
482 
483 static int __init aat2870_init(void)
484 {
485 	return i2c_add_driver(&aat2870_i2c_driver);
486 }
487 subsys_initcall(aat2870_init);
488