1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* STMicroelectronics uvis25 sensor driver
*
* Copyright 2017 STMicroelectronics Inc.
*
* Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/iio/sysfs.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/interrupt.h>
#include <linux/irqreturn.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/buffer.h>
#include <linux/regmap.h>
#include "st_uvis25.h"
#define ST_UVIS25_REG_WHOAMI_ADDR 0x0f
#define ST_UVIS25_REG_WHOAMI_VAL 0xca
#define ST_UVIS25_REG_CTRL1_ADDR 0x20
#define ST_UVIS25_REG_ODR_MASK BIT(0)
#define ST_UVIS25_REG_BDU_MASK BIT(1)
#define ST_UVIS25_REG_CTRL2_ADDR 0x21
#define ST_UVIS25_REG_BOOT_MASK BIT(7)
#define ST_UVIS25_REG_CTRL3_ADDR 0x22
#define ST_UVIS25_REG_HL_MASK BIT(7)
#define ST_UVIS25_REG_STATUS_ADDR 0x27
#define ST_UVIS25_REG_UV_DA_MASK BIT(0)
#define ST_UVIS25_REG_OUT_ADDR 0x28
static const struct iio_chan_spec st_uvis25_channels[] = {
{
.type = IIO_UVINDEX,
.address = ST_UVIS25_REG_OUT_ADDR,
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
.scan_index = 0,
.scan_type = {
.sign = 'u',
.realbits = 8,
.storagebits = 8,
},
},
IIO_CHAN_SOFT_TIMESTAMP(1),
};
static int st_uvis25_check_whoami(struct st_uvis25_hw *hw)
{
int err, data;
err = regmap_read(hw->regmap, ST_UVIS25_REG_WHOAMI_ADDR, &data);
if (err < 0) {
dev_err(regmap_get_device(hw->regmap),
"failed to read whoami register\n");
return err;
}
if (data != ST_UVIS25_REG_WHOAMI_VAL) {
dev_err(regmap_get_device(hw->regmap),
"wrong whoami {%02x vs %02x}\n",
data, ST_UVIS25_REG_WHOAMI_VAL);
return -ENODEV;
}
return 0;
}
static int st_uvis25_set_enable(struct st_uvis25_hw *hw, bool enable)
{
int err;
err = regmap_update_bits(hw->regmap, ST_UVIS25_REG_CTRL1_ADDR,
ST_UVIS25_REG_ODR_MASK, enable);
if (err < 0)
return err;
hw->enabled = enable;
return 0;
}
static int st_uvis25_read_oneshot(struct st_uvis25_hw *hw, u8 addr, int *val)
{
int err;
err = st_uvis25_set_enable(hw, true);
if (err < 0)
return err;
msleep(1500);
/*
* in order to avoid possible race conditions with interrupt
* generation, disable the sensor first and then poll output
* register. That sequence guarantees the interrupt will be reset
* when irq line is unmasked
*/
err = st_uvis25_set_enable(hw, false);
if (err < 0)
return err;
err = regmap_read(hw->regmap, addr, val);
return err < 0 ? err : IIO_VAL_INT;
}
static int st_uvis25_read_raw(struct iio_dev *iio_dev,
struct iio_chan_spec const *ch,
int *val, int *val2, long mask)
{
int ret;
ret = iio_device_claim_direct_mode(iio_dev);
if (ret)
return ret;
switch (mask) {
case IIO_CHAN_INFO_PROCESSED: {
struct st_uvis25_hw *hw = iio_priv(iio_dev);
/*
* mask irq line during oneshot read since the sensor
* does not export the capability to disable data-ready line
* in the register map and it is enabled by default.
* If the line is unmasked during read_raw() it will be set
* active and never reset since the trigger is disabled
*/
if (hw->irq > 0)
disable_irq(hw->irq);
ret = st_uvis25_read_oneshot(hw, ch->address, val);
if (hw->irq > 0)
enable_irq(hw->irq);
break;
}
default:
ret = -EINVAL;
break;
}
iio_device_release_direct_mode(iio_dev);
return ret;
}
static irqreturn_t st_uvis25_trigger_handler_thread(int irq, void *private)
{
struct st_uvis25_hw *hw = private;
int err, status;
err = regmap_read(hw->regmap, ST_UVIS25_REG_STATUS_ADDR, &status);
if (err < 0)
return IRQ_HANDLED;
if (!(status & ST_UVIS25_REG_UV_DA_MASK))
return IRQ_NONE;
iio_trigger_poll_nested(hw->trig);
return IRQ_HANDLED;
}
static int st_uvis25_allocate_trigger(struct iio_dev *iio_dev)
{
struct st_uvis25_hw *hw = iio_priv(iio_dev);
struct device *dev = regmap_get_device(hw->regmap);
bool irq_active_low = false;
unsigned long irq_type;
int err;
irq_type = irq_get_trigger_type(hw->irq);
switch (irq_type) {
case IRQF_TRIGGER_HIGH:
case IRQF_TRIGGER_RISING:
break;
case IRQF_TRIGGER_LOW:
case IRQF_TRIGGER_FALLING:
irq_active_low = true;
break;
default:
dev_info(dev, "mode %lx unsupported\n", irq_type);
return -EINVAL;
}
err = regmap_update_bits(hw->regmap, ST_UVIS25_REG_CTRL3_ADDR,
ST_UVIS25_REG_HL_MASK, irq_active_low);
if (err < 0)
return err;
err = devm_request_threaded_irq(dev, hw->irq, NULL,
st_uvis25_trigger_handler_thread,
irq_type | IRQF_ONESHOT,
iio_dev->name, hw);
if (err) {
dev_err(dev, "failed to request trigger irq %d\n",
hw->irq);
return err;
}
hw->trig = devm_iio_trigger_alloc(dev, "%s-trigger",
iio_dev->name);
if (!hw->trig)
return -ENOMEM;
iio_trigger_set_drvdata(hw->trig, iio_dev);
return devm_iio_trigger_register(dev, hw->trig);
}
static int st_uvis25_buffer_preenable(struct iio_dev *iio_dev)
{
return st_uvis25_set_enable(iio_priv(iio_dev), true);
}
static int st_uvis25_buffer_postdisable(struct iio_dev *iio_dev)
{
return st_uvis25_set_enable(iio_priv(iio_dev), false);
}
static const struct iio_buffer_setup_ops st_uvis25_buffer_ops = {
.preenable = st_uvis25_buffer_preenable,
.postdisable = st_uvis25_buffer_postdisable,
};
static irqreturn_t st_uvis25_buffer_handler_thread(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *iio_dev = pf->indio_dev;
struct st_uvis25_hw *hw = iio_priv(iio_dev);
unsigned int val;
int err;
err = regmap_read(hw->regmap, ST_UVIS25_REG_OUT_ADDR, &val);
if (err < 0)
goto out;
hw->scan.chan = val;
iio_push_to_buffers_with_timestamp(iio_dev, &hw->scan,
iio_get_time_ns(iio_dev));
out:
iio_trigger_notify_done(hw->trig);
return IRQ_HANDLED;
}
static int st_uvis25_allocate_buffer(struct iio_dev *iio_dev)
{
struct st_uvis25_hw *hw = iio_priv(iio_dev);
return devm_iio_triggered_buffer_setup(regmap_get_device(hw->regmap),
iio_dev, NULL,
st_uvis25_buffer_handler_thread,
&st_uvis25_buffer_ops);
}
static const struct iio_info st_uvis25_info = {
.read_raw = st_uvis25_read_raw,
};
static int st_uvis25_init_sensor(struct st_uvis25_hw *hw)
{
int err;
err = regmap_update_bits(hw->regmap, ST_UVIS25_REG_CTRL2_ADDR,
ST_UVIS25_REG_BOOT_MASK, 1);
if (err < 0)
return err;
msleep(2000);
return regmap_update_bits(hw->regmap, ST_UVIS25_REG_CTRL1_ADDR,
ST_UVIS25_REG_BDU_MASK, 1);
}
int st_uvis25_probe(struct device *dev, int irq, struct regmap *regmap)
{
struct st_uvis25_hw *hw;
struct iio_dev *iio_dev;
int err;
iio_dev = devm_iio_device_alloc(dev, sizeof(*hw));
if (!iio_dev)
return -ENOMEM;
dev_set_drvdata(dev, iio_dev);
hw = iio_priv(iio_dev);
hw->irq = irq;
hw->regmap = regmap;
err = st_uvis25_check_whoami(hw);
if (err < 0)
return err;
iio_dev->modes = INDIO_DIRECT_MODE;
iio_dev->channels = st_uvis25_channels;
iio_dev->num_channels = ARRAY_SIZE(st_uvis25_channels);
iio_dev->name = ST_UVIS25_DEV_NAME;
iio_dev->info = &st_uvis25_info;
err = st_uvis25_init_sensor(hw);
if (err < 0)
return err;
if (hw->irq > 0) {
err = st_uvis25_allocate_buffer(iio_dev);
if (err < 0)
return err;
err = st_uvis25_allocate_trigger(iio_dev);
if (err)
return err;
}
return devm_iio_device_register(dev, iio_dev);
}
EXPORT_SYMBOL_NS(st_uvis25_probe, "IIO_UVIS25");
static int st_uvis25_suspend(struct device *dev)
{
struct iio_dev *iio_dev = dev_get_drvdata(dev);
struct st_uvis25_hw *hw = iio_priv(iio_dev);
return regmap_clear_bits(hw->regmap, ST_UVIS25_REG_CTRL1_ADDR,
ST_UVIS25_REG_ODR_MASK);
}
static int st_uvis25_resume(struct device *dev)
{
struct iio_dev *iio_dev = dev_get_drvdata(dev);
struct st_uvis25_hw *hw = iio_priv(iio_dev);
if (hw->enabled)
return regmap_update_bits(hw->regmap, ST_UVIS25_REG_CTRL1_ADDR,
ST_UVIS25_REG_ODR_MASK, 1);
return 0;
}
EXPORT_NS_SIMPLE_DEV_PM_OPS(st_uvis25_pm_ops, st_uvis25_suspend, st_uvis25_resume, IIO_UVIS25);
MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>");
MODULE_DESCRIPTION("STMicroelectronics uvis25 sensor driver");
MODULE_LICENSE("GPL v2");
|
