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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * apds9802als.c - apds9802 ALS Driver
4 *
5 * Copyright (C) 2009 Intel Corp
6 *
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 *
9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
10 */
11
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/i2c.h>
15#include <linux/err.h>
16#include <linux/delay.h>
17#include <linux/mutex.h>
18#include <linux/sysfs.h>
19#include <linux/pm_runtime.h>
20
21#define ALS_MIN_RANGE_VAL 1
22#define ALS_MAX_RANGE_VAL 2
23#define POWER_STA_ENABLE 1
24#define POWER_STA_DISABLE 0
25
26#define DRIVER_NAME "apds9802als"
27
28struct als_data {
29 struct mutex mutex;
30};
31
32static ssize_t als_sensing_range_show(struct device *dev,
33 struct device_attribute *attr, char *buf)
34{
35 struct i2c_client *client = to_i2c_client(dev);
36 int val;
37
38 val = i2c_smbus_read_byte_data(client, 0x81);
39 if (val < 0)
40 return val;
41 if (val & 1)
42 return sprintf(buf, "4095\n");
43 else
44 return sprintf(buf, "65535\n");
45}
46
47static int als_wait_for_data_ready(struct device *dev)
48{
49 struct i2c_client *client = to_i2c_client(dev);
50 int ret;
51 int retry = 10;
52
53 do {
54 msleep(30);
55 ret = i2c_smbus_read_byte_data(client, 0x86);
56 } while (!(ret & 0x80) && retry--);
57
58 if (retry < 0) {
59 dev_warn(dev, "timeout waiting for data ready\n");
60 return -ETIMEDOUT;
61 }
62
63 return 0;
64}
65
66static ssize_t als_lux0_input_data_show(struct device *dev,
67 struct device_attribute *attr, char *buf)
68{
69 struct i2c_client *client = to_i2c_client(dev);
70 struct als_data *data = i2c_get_clientdata(client);
71 int ret_val;
72 int temp;
73
74 /* Protect against parallel reads */
75 pm_runtime_get_sync(dev);
76 mutex_lock(&data->mutex);
77
78 /* clear EOC interrupt status */
79 i2c_smbus_write_byte(client, 0x40);
80 /* start measurement */
81 temp = i2c_smbus_read_byte_data(client, 0x81);
82 i2c_smbus_write_byte_data(client, 0x81, temp | 0x08);
83
84 ret_val = als_wait_for_data_ready(dev);
85 if (ret_val < 0)
86 goto failed;
87
88 temp = i2c_smbus_read_byte_data(client, 0x8C); /* LSB data */
89 if (temp < 0) {
90 ret_val = temp;
91 goto failed;
92 }
93 ret_val = i2c_smbus_read_byte_data(client, 0x8D); /* MSB data */
94 if (ret_val < 0)
95 goto failed;
96
97 mutex_unlock(&data->mutex);
98 pm_runtime_put_sync(dev);
99
100 temp = (ret_val << 8) | temp;
101 return sprintf(buf, "%d\n", temp);
102failed:
103 mutex_unlock(&data->mutex);
104 pm_runtime_put_sync(dev);
105 return ret_val;
106}
107
108static ssize_t als_sensing_range_store(struct device *dev,
109 struct device_attribute *attr, const char *buf, size_t count)
110{
111 struct i2c_client *client = to_i2c_client(dev);
112 struct als_data *data = i2c_get_clientdata(client);
113 int ret_val;
114 unsigned long val;
115
116 ret_val = kstrtoul(buf, 10, &val);
117 if (ret_val)
118 return ret_val;
119
120 if (val < 4096)
121 val = 1;
122 else if (val < 65536)
123 val = 2;
124 else
125 return -ERANGE;
126
127 pm_runtime_get_sync(dev);
128
129 /* Make sure nobody else reads/modifies/writes 0x81 while we
130 are active */
131 mutex_lock(&data->mutex);
132
133 ret_val = i2c_smbus_read_byte_data(client, 0x81);
134 if (ret_val < 0)
135 goto fail;
136
137 /* Reset the bits before setting them */
138 ret_val = ret_val & 0xFA;
139
140 if (val == 1) /* Setting detection range up to 4k LUX */
141 ret_val = (ret_val | 0x01);
142 else /* Setting detection range up to 64k LUX*/
143 ret_val = (ret_val | 0x00);
144
145 ret_val = i2c_smbus_write_byte_data(client, 0x81, ret_val);
146
147 if (ret_val >= 0) {
148 /* All OK */
149 mutex_unlock(&data->mutex);
150 pm_runtime_put_sync(dev);
151 return count;
152 }
153fail:
154 mutex_unlock(&data->mutex);
155 pm_runtime_put_sync(dev);
156 return ret_val;
157}
158
159static int als_set_power_state(struct i2c_client *client, bool on_off)
160{
161 int ret_val;
162 struct als_data *data = i2c_get_clientdata(client);
163
164 mutex_lock(&data->mutex);
165 ret_val = i2c_smbus_read_byte_data(client, 0x80);
166 if (ret_val < 0)
167 goto fail;
168 if (on_off)
169 ret_val = ret_val | 0x01;
170 else
171 ret_val = ret_val & 0xFE;
172 ret_val = i2c_smbus_write_byte_data(client, 0x80, ret_val);
173fail:
174 mutex_unlock(&data->mutex);
175 return ret_val;
176}
177
178static DEVICE_ATTR(lux0_sensor_range, S_IRUGO | S_IWUSR,
179 als_sensing_range_show, als_sensing_range_store);
180static DEVICE_ATTR(lux0_input, S_IRUGO, als_lux0_input_data_show, NULL);
181
182static struct attribute *mid_att_als[] = {
183 &dev_attr_lux0_sensor_range.attr,
184 &dev_attr_lux0_input.attr,
185 NULL
186};
187
188static const struct attribute_group m_als_gr = {
189 .name = "apds9802als",
190 .attrs = mid_att_als
191};
192
193static int als_set_default_config(struct i2c_client *client)
194{
195 int ret_val;
196 /* Write the command and then switch on */
197 ret_val = i2c_smbus_write_byte_data(client, 0x80, 0x01);
198 if (ret_val < 0) {
199 dev_err(&client->dev, "failed default switch on write\n");
200 return ret_val;
201 }
202 /* detection range: 1~64K Lux, maunal measurement */
203 ret_val = i2c_smbus_write_byte_data(client, 0x81, 0x08);
204 if (ret_val < 0)
205 dev_err(&client->dev, "failed default LUX on write\n");
206
207 /* We always get 0 for the 1st measurement after system power on,
208 * so make sure it is finished before user asks for data.
209 */
210 als_wait_for_data_ready(&client->dev);
211
212 return ret_val;
213}
214
215static int apds9802als_probe(struct i2c_client *client)
216{
217 int res;
218 struct als_data *data;
219
220 data = kzalloc_obj(struct als_data);
221 if (data == NULL) {
222 dev_err(&client->dev, "Memory allocation failed\n");
223 return -ENOMEM;
224 }
225 i2c_set_clientdata(client, data);
226 res = sysfs_create_group(&client->dev.kobj, &m_als_gr);
227 if (res) {
228 dev_err(&client->dev, "device create file failed\n");
229 goto als_error1;
230 }
231 dev_info(&client->dev, "ALS chip found\n");
232 als_set_default_config(client);
233 mutex_init(&data->mutex);
234
235 pm_runtime_set_active(&client->dev);
236 pm_runtime_enable(&client->dev);
237
238 return res;
239als_error1:
240 kfree(data);
241 return res;
242}
243
244static void apds9802als_remove(struct i2c_client *client)
245{
246 struct als_data *data = i2c_get_clientdata(client);
247
248 pm_runtime_get_sync(&client->dev);
249
250 als_set_power_state(client, false);
251 sysfs_remove_group(&client->dev.kobj, &m_als_gr);
252
253 pm_runtime_disable(&client->dev);
254 pm_runtime_set_suspended(&client->dev);
255 pm_runtime_put_noidle(&client->dev);
256
257 kfree(data);
258}
259
260#ifdef CONFIG_PM
261
262static int apds9802als_suspend(struct device *dev)
263{
264 struct i2c_client *client = to_i2c_client(dev);
265
266 als_set_power_state(client, false);
267 return 0;
268}
269
270static int apds9802als_resume(struct device *dev)
271{
272 struct i2c_client *client = to_i2c_client(dev);
273
274 als_set_power_state(client, true);
275 return 0;
276}
277
278static UNIVERSAL_DEV_PM_OPS(apds9802als_pm_ops, apds9802als_suspend,
279 apds9802als_resume, NULL);
280
281#define APDS9802ALS_PM_OPS (&apds9802als_pm_ops)
282
283#else /* CONFIG_PM */
284#define APDS9802ALS_PM_OPS NULL
285#endif /* CONFIG_PM */
286
287static const struct i2c_device_id apds9802als_id[] = {
288 { .name = DRIVER_NAME },
289 { }
290};
291
292MODULE_DEVICE_TABLE(i2c, apds9802als_id);
293
294static struct i2c_driver apds9802als_driver = {
295 .driver = {
296 .name = DRIVER_NAME,
297 .pm = APDS9802ALS_PM_OPS,
298 },
299 .probe = apds9802als_probe,
300 .remove = apds9802als_remove,
301 .id_table = apds9802als_id,
302};
303
304module_i2c_driver(apds9802als_driver);
305
306MODULE_AUTHOR("Anantha Narayanan <[email protected]");
307MODULE_DESCRIPTION("Avago apds9802als ALS Driver");
308MODULE_LICENSE("GPL v2");