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 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
404 out_disable:
405 aat2870_disable(aat2870);
406 return ret;
407 }
408
aat2870_i2c_suspend(struct device * dev)409 static 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
aat2870_i2c_resume(struct device * dev)419 static 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
438 static DEFINE_SIMPLE_DEV_PM_OPS(aat2870_pm_ops, aat2870_i2c_suspend,
439 aat2870_i2c_resume);
440
441 static const struct i2c_device_id aat2870_i2c_id_table[] = {
442 { "aat2870", 0 },
443 { }
444 };
445
446 static 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
aat2870_init(void)456 static int __init aat2870_init(void)
457 {
458 return i2c_add_driver(&aat2870_i2c_driver);
459 }
460 subsys_initcall(aat2870_init);
461