This source file includes following definitions.
- bh1780_write
- bh1780_read
- bh1780_read_word
- bh1780_debugfs_reg_access
- bh1780_read_raw
- bh1780_probe
- bh1780_remove
- bh1780_runtime_suspend
- bh1780_runtime_resume
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11 #include <linux/i2c.h>
12 #include <linux/slab.h>
13 #include <linux/platform_device.h>
14 #include <linux/delay.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/iio/iio.h>
19 #include <linux/iio/sysfs.h>
20 #include <linux/bitops.h>
21
22 #define BH1780_CMD_BIT BIT(7)
23 #define BH1780_REG_CONTROL 0x00
24 #define BH1780_REG_PARTID 0x0A
25 #define BH1780_REG_MANFID 0x0B
26 #define BH1780_REG_DLOW 0x0C
27 #define BH1780_REG_DHIGH 0x0D
28
29 #define BH1780_REVMASK GENMASK(3,0)
30 #define BH1780_POWMASK GENMASK(1,0)
31 #define BH1780_POFF (0x0)
32 #define BH1780_PON (0x3)
33
34
35 #define BH1780_PON_DELAY 2
36
37 #define BH1780_INTERVAL 250
38
39 struct bh1780_data {
40 struct i2c_client *client;
41 };
42
43 static int bh1780_write(struct bh1780_data *bh1780, u8 reg, u8 val)
44 {
45 int ret = i2c_smbus_write_byte_data(bh1780->client,
46 BH1780_CMD_BIT | reg,
47 val);
48 if (ret < 0)
49 dev_err(&bh1780->client->dev,
50 "i2c_smbus_write_byte_data failed error "
51 "%d, register %01x\n",
52 ret, reg);
53 return ret;
54 }
55
56 static int bh1780_read(struct bh1780_data *bh1780, u8 reg)
57 {
58 int ret = i2c_smbus_read_byte_data(bh1780->client,
59 BH1780_CMD_BIT | reg);
60 if (ret < 0)
61 dev_err(&bh1780->client->dev,
62 "i2c_smbus_read_byte_data failed error "
63 "%d, register %01x\n",
64 ret, reg);
65 return ret;
66 }
67
68 static int bh1780_read_word(struct bh1780_data *bh1780, u8 reg)
69 {
70 int ret = i2c_smbus_read_word_data(bh1780->client,
71 BH1780_CMD_BIT | reg);
72 if (ret < 0)
73 dev_err(&bh1780->client->dev,
74 "i2c_smbus_read_word_data failed error "
75 "%d, register %01x\n",
76 ret, reg);
77 return ret;
78 }
79
80 static int bh1780_debugfs_reg_access(struct iio_dev *indio_dev,
81 unsigned int reg, unsigned int writeval,
82 unsigned int *readval)
83 {
84 struct bh1780_data *bh1780 = iio_priv(indio_dev);
85 int ret;
86
87 if (!readval)
88 return bh1780_write(bh1780, (u8)reg, (u8)writeval);
89
90 ret = bh1780_read(bh1780, (u8)reg);
91 if (ret < 0)
92 return ret;
93
94 *readval = ret;
95
96 return 0;
97 }
98
99 static int bh1780_read_raw(struct iio_dev *indio_dev,
100 struct iio_chan_spec const *chan,
101 int *val, int *val2, long mask)
102 {
103 struct bh1780_data *bh1780 = iio_priv(indio_dev);
104 int value;
105
106 switch (mask) {
107 case IIO_CHAN_INFO_RAW:
108 switch (chan->type) {
109 case IIO_LIGHT:
110 pm_runtime_get_sync(&bh1780->client->dev);
111 value = bh1780_read_word(bh1780, BH1780_REG_DLOW);
112 if (value < 0)
113 return value;
114 pm_runtime_mark_last_busy(&bh1780->client->dev);
115 pm_runtime_put_autosuspend(&bh1780->client->dev);
116 *val = value;
117
118 return IIO_VAL_INT;
119 default:
120 return -EINVAL;
121 }
122 case IIO_CHAN_INFO_INT_TIME:
123 *val = 0;
124 *val2 = BH1780_INTERVAL * 1000;
125 return IIO_VAL_INT_PLUS_MICRO;
126 default:
127 return -EINVAL;
128 }
129 }
130
131 static const struct iio_info bh1780_info = {
132 .read_raw = bh1780_read_raw,
133 .debugfs_reg_access = bh1780_debugfs_reg_access,
134 };
135
136 static const struct iio_chan_spec bh1780_channels[] = {
137 {
138 .type = IIO_LIGHT,
139 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
140 BIT(IIO_CHAN_INFO_INT_TIME)
141 }
142 };
143
144 static int bh1780_probe(struct i2c_client *client,
145 const struct i2c_device_id *id)
146 {
147 int ret;
148 struct bh1780_data *bh1780;
149 struct i2c_adapter *adapter = client->adapter;
150 struct iio_dev *indio_dev;
151
152 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
153 return -EIO;
154
155 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*bh1780));
156 if (!indio_dev)
157 return -ENOMEM;
158
159 bh1780 = iio_priv(indio_dev);
160 bh1780->client = client;
161 i2c_set_clientdata(client, indio_dev);
162
163
164 ret = bh1780_write(bh1780, BH1780_REG_CONTROL, BH1780_PON);
165 if (ret < 0)
166 return ret;
167 msleep(BH1780_PON_DELAY);
168 pm_runtime_get_noresume(&client->dev);
169 pm_runtime_set_active(&client->dev);
170 pm_runtime_enable(&client->dev);
171
172 ret = bh1780_read(bh1780, BH1780_REG_PARTID);
173 if (ret < 0)
174 goto out_disable_pm;
175 dev_info(&client->dev,
176 "Ambient Light Sensor, Rev : %lu\n",
177 (ret & BH1780_REVMASK));
178
179
180
181
182
183
184 pm_runtime_set_autosuspend_delay(&client->dev, 5000);
185 pm_runtime_use_autosuspend(&client->dev);
186 pm_runtime_put(&client->dev);
187
188 indio_dev->dev.parent = &client->dev;
189 indio_dev->info = &bh1780_info;
190 indio_dev->name = "bh1780";
191 indio_dev->channels = bh1780_channels;
192 indio_dev->num_channels = ARRAY_SIZE(bh1780_channels);
193 indio_dev->modes = INDIO_DIRECT_MODE;
194
195 ret = iio_device_register(indio_dev);
196 if (ret)
197 goto out_disable_pm;
198 return 0;
199
200 out_disable_pm:
201 pm_runtime_put_noidle(&client->dev);
202 pm_runtime_disable(&client->dev);
203 return ret;
204 }
205
206 static int bh1780_remove(struct i2c_client *client)
207 {
208 struct iio_dev *indio_dev = i2c_get_clientdata(client);
209 struct bh1780_data *bh1780 = iio_priv(indio_dev);
210 int ret;
211
212 iio_device_unregister(indio_dev);
213 pm_runtime_get_sync(&client->dev);
214 pm_runtime_put_noidle(&client->dev);
215 pm_runtime_disable(&client->dev);
216 ret = bh1780_write(bh1780, BH1780_REG_CONTROL, BH1780_POFF);
217 if (ret < 0) {
218 dev_err(&client->dev, "failed to power off\n");
219 return ret;
220 }
221
222 return 0;
223 }
224
225 #ifdef CONFIG_PM
226 static int bh1780_runtime_suspend(struct device *dev)
227 {
228 struct i2c_client *client = to_i2c_client(dev);
229 struct iio_dev *indio_dev = i2c_get_clientdata(client);
230 struct bh1780_data *bh1780 = iio_priv(indio_dev);
231 int ret;
232
233 ret = bh1780_write(bh1780, BH1780_REG_CONTROL, BH1780_POFF);
234 if (ret < 0) {
235 dev_err(dev, "failed to runtime suspend\n");
236 return ret;
237 }
238
239 return 0;
240 }
241
242 static int bh1780_runtime_resume(struct device *dev)
243 {
244 struct i2c_client *client = to_i2c_client(dev);
245 struct iio_dev *indio_dev = i2c_get_clientdata(client);
246 struct bh1780_data *bh1780 = iio_priv(indio_dev);
247 int ret;
248
249 ret = bh1780_write(bh1780, BH1780_REG_CONTROL, BH1780_PON);
250 if (ret < 0) {
251 dev_err(dev, "failed to runtime resume\n");
252 return ret;
253 }
254
255
256 msleep(BH1780_PON_DELAY + BH1780_INTERVAL);
257
258 return 0;
259 }
260 #endif
261
262 static const struct dev_pm_ops bh1780_dev_pm_ops = {
263 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
264 pm_runtime_force_resume)
265 SET_RUNTIME_PM_OPS(bh1780_runtime_suspend,
266 bh1780_runtime_resume, NULL)
267 };
268
269 static const struct i2c_device_id bh1780_id[] = {
270 { "bh1780", 0 },
271 { },
272 };
273
274 MODULE_DEVICE_TABLE(i2c, bh1780_id);
275
276 #ifdef CONFIG_OF
277 static const struct of_device_id of_bh1780_match[] = {
278 { .compatible = "rohm,bh1780gli", },
279 {},
280 };
281 MODULE_DEVICE_TABLE(of, of_bh1780_match);
282 #endif
283
284 static struct i2c_driver bh1780_driver = {
285 .probe = bh1780_probe,
286 .remove = bh1780_remove,
287 .id_table = bh1780_id,
288 .driver = {
289 .name = "bh1780",
290 .pm = &bh1780_dev_pm_ops,
291 .of_match_table = of_match_ptr(of_bh1780_match),
292 },
293 };
294
295 module_i2c_driver(bh1780_driver);
296
297 MODULE_DESCRIPTION("ROHM BH1780GLI Ambient Light Sensor Driver");
298 MODULE_LICENSE("GPL");
299 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");