Commit | Line | Data |
---|---|---|
1f0477f1 LW |
1 | /* |
2 | * ROHM 1780GLI Ambient Light Sensor Driver | |
3 | * | |
4 | * Copyright (C) 2016 Linaro Ltd. | |
5 | * Author: Linus Walleij <linus.walleij@linaro.org> | |
6 | * Loosely based on the previous BH1780 ALS misc driver | |
7 | * Copyright (C) 2010 Texas Instruments | |
8 | * Author: Hemanth V <hemanthv@ti.com> | |
9 | */ | |
10 | #include <linux/i2c.h> | |
11 | #include <linux/slab.h> | |
12 | #include <linux/platform_device.h> | |
13 | #include <linux/delay.h> | |
14 | #include <linux/module.h> | |
15 | #include <linux/of.h> | |
16 | #include <linux/pm_runtime.h> | |
17 | #include <linux/iio/iio.h> | |
18 | #include <linux/iio/sysfs.h> | |
19 | #include <linux/bitops.h> | |
20 | ||
21 | #define BH1780_CMD_BIT BIT(7) | |
22 | #define BH1780_REG_CONTROL 0x00 | |
23 | #define BH1780_REG_PARTID 0x0A | |
24 | #define BH1780_REG_MANFID 0x0B | |
25 | #define BH1780_REG_DLOW 0x0C | |
26 | #define BH1780_REG_DHIGH 0x0D | |
27 | ||
28 | #define BH1780_REVMASK GENMASK(3,0) | |
29 | #define BH1780_POWMASK GENMASK(1,0) | |
30 | #define BH1780_POFF (0x0) | |
31 | #define BH1780_PON (0x3) | |
32 | ||
33 | /* power on settling time in ms */ | |
34 | #define BH1780_PON_DELAY 2 | |
35 | /* max time before value available in ms */ | |
36 | #define BH1780_INTERVAL 250 | |
37 | ||
38 | struct bh1780_data { | |
39 | struct i2c_client *client; | |
40 | }; | |
41 | ||
42 | static int bh1780_write(struct bh1780_data *bh1780, u8 reg, u8 val) | |
43 | { | |
44 | int ret = i2c_smbus_write_byte_data(bh1780->client, | |
45 | BH1780_CMD_BIT | reg, | |
46 | val); | |
47 | if (ret < 0) | |
48 | dev_err(&bh1780->client->dev, | |
49 | "i2c_smbus_write_byte_data failed error " | |
50 | "%d, register %01x\n", | |
51 | ret, reg); | |
52 | return ret; | |
53 | } | |
54 | ||
55 | static int bh1780_read(struct bh1780_data *bh1780, u8 reg) | |
56 | { | |
57 | int ret = i2c_smbus_read_byte_data(bh1780->client, | |
58 | BH1780_CMD_BIT | reg); | |
59 | if (ret < 0) | |
60 | dev_err(&bh1780->client->dev, | |
61 | "i2c_smbus_read_byte_data failed error " | |
62 | "%d, register %01x\n", | |
63 | ret, reg); | |
64 | return ret; | |
65 | } | |
66 | ||
67 | static int bh1780_read_word(struct bh1780_data *bh1780, u8 reg) | |
68 | { | |
69 | int ret = i2c_smbus_read_word_data(bh1780->client, | |
70 | BH1780_CMD_BIT | reg); | |
71 | if (ret < 0) | |
72 | dev_err(&bh1780->client->dev, | |
73 | "i2c_smbus_read_word_data failed error " | |
74 | "%d, register %01x\n", | |
75 | ret, reg); | |
76 | return ret; | |
77 | } | |
78 | ||
79 | static int bh1780_debugfs_reg_access(struct iio_dev *indio_dev, | |
80 | unsigned int reg, unsigned int writeval, | |
81 | unsigned int *readval) | |
82 | { | |
83 | struct bh1780_data *bh1780 = iio_priv(indio_dev); | |
84 | int ret; | |
85 | ||
86 | if (!readval) | |
87 | bh1780_write(bh1780, (u8)reg, (u8)writeval); | |
88 | ||
89 | ret = bh1780_read(bh1780, (u8)reg); | |
90 | if (ret < 0) | |
91 | return ret; | |
92 | ||
93 | *readval = ret; | |
94 | ||
95 | return 0; | |
96 | } | |
97 | ||
98 | static int bh1780_read_raw(struct iio_dev *indio_dev, | |
99 | struct iio_chan_spec const *chan, | |
100 | int *val, int *val2, long mask) | |
101 | { | |
102 | struct bh1780_data *bh1780 = iio_priv(indio_dev); | |
103 | int value; | |
104 | ||
105 | switch (mask) { | |
106 | case IIO_CHAN_INFO_RAW: | |
107 | switch (chan->type) { | |
108 | case IIO_LIGHT: | |
109 | pm_runtime_get_sync(&bh1780->client->dev); | |
110 | value = bh1780_read_word(bh1780, BH1780_REG_DLOW); | |
111 | if (value < 0) | |
112 | return value; | |
113 | pm_runtime_mark_last_busy(&bh1780->client->dev); | |
114 | pm_runtime_put_autosuspend(&bh1780->client->dev); | |
115 | *val = value; | |
116 | ||
117 | return IIO_VAL_INT; | |
118 | default: | |
119 | return -EINVAL; | |
120 | } | |
121 | case IIO_CHAN_INFO_INT_TIME: | |
122 | *val = 0; | |
123 | *val2 = BH1780_INTERVAL * 1000; | |
124 | return IIO_VAL_INT_PLUS_MICRO; | |
125 | default: | |
126 | return -EINVAL; | |
127 | } | |
128 | } | |
129 | ||
130 | static const struct iio_info bh1780_info = { | |
131 | .driver_module = THIS_MODULE, | |
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 = to_i2c_adapter(client->dev.parent); | |
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 | /* Power up the device */ | |
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 | * As the device takes 250 ms to even come up with a fresh | |
181 | * measurement after power-on, do not shut it down unnecessarily. | |
182 | * Set autosuspend to a five seconds. | |
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 = id->name; | |
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 bh1780_data *bh1780 = i2c_get_clientdata(client); | |
230 | int ret; | |
231 | ||
232 | ret = bh1780_write(bh1780, BH1780_REG_CONTROL, BH1780_POFF); | |
233 | if (ret < 0) { | |
234 | dev_err(dev, "failed to runtime suspend\n"); | |
235 | return ret; | |
236 | } | |
237 | ||
238 | return 0; | |
239 | } | |
240 | ||
241 | static int bh1780_runtime_resume(struct device *dev) | |
242 | { | |
243 | struct i2c_client *client = to_i2c_client(dev); | |
244 | struct bh1780_data *bh1780 = i2c_get_clientdata(client); | |
245 | int ret; | |
246 | ||
247 | ret = bh1780_write(bh1780, BH1780_REG_CONTROL, BH1780_PON); | |
248 | if (ret < 0) { | |
249 | dev_err(dev, "failed to runtime resume\n"); | |
250 | return ret; | |
251 | } | |
252 | ||
253 | /* Wait for power on, then for a value to be available */ | |
254 | msleep(BH1780_PON_DELAY + BH1780_INTERVAL); | |
255 | ||
256 | return 0; | |
257 | } | |
258 | #endif /* CONFIG_PM */ | |
259 | ||
260 | static const struct dev_pm_ops bh1780_dev_pm_ops = { | |
261 | SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, | |
262 | pm_runtime_force_resume) | |
263 | SET_RUNTIME_PM_OPS(bh1780_runtime_suspend, | |
264 | bh1780_runtime_resume, NULL) | |
265 | }; | |
266 | ||
267 | static const struct i2c_device_id bh1780_id[] = { | |
268 | { "bh1780", 0 }, | |
269 | { }, | |
270 | }; | |
271 | ||
272 | MODULE_DEVICE_TABLE(i2c, bh1780_id); | |
273 | ||
274 | #ifdef CONFIG_OF | |
275 | static const struct of_device_id of_bh1780_match[] = { | |
276 | { .compatible = "rohm,bh1780gli", }, | |
277 | {}, | |
278 | }; | |
279 | MODULE_DEVICE_TABLE(of, of_bh1780_match); | |
280 | #endif | |
281 | ||
282 | static struct i2c_driver bh1780_driver = { | |
283 | .probe = bh1780_probe, | |
284 | .remove = bh1780_remove, | |
285 | .id_table = bh1780_id, | |
286 | .driver = { | |
287 | .name = "bh1780", | |
288 | .pm = &bh1780_dev_pm_ops, | |
289 | .of_match_table = of_match_ptr(of_bh1780_match), | |
290 | }, | |
291 | }; | |
292 | ||
293 | module_i2c_driver(bh1780_driver); | |
294 | ||
295 | MODULE_DESCRIPTION("ROHM BH1780GLI Ambient Light Sensor Driver"); | |
296 | MODULE_LICENSE("GPL"); | |
297 | MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>"); |