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
|
// SPDX-License-Identifier: GPL-2.0+
/*
* Azoteq IQS624/625 Angular Position Sensors
*
* Copyright (C) 2019 Jeff LaBundy <jeff@labundy.com>
*/
#include <linux/device.h>
#include <linux/iio/events.h>
#include <linux/iio/iio.h>
#include <linux/kernel.h>
#include <linux/mfd/iqs62x.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/notifier.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#define IQS624_POS_DEG_OUT 0x16
#define IQS624_POS_SCALE1 (314159 / 180)
#define IQS624_POS_SCALE2 100000
struct iqs624_pos_private {
struct iqs62x_core *iqs62x;
struct iio_dev *indio_dev;
struct notifier_block notifier;
struct mutex lock;
bool angle_en;
u16 angle;
};
static int iqs624_pos_angle_en(struct iqs62x_core *iqs62x, bool angle_en)
{
unsigned int event_mask = IQS624_HALL_UI_WHL_EVENT;
/*
* The IQS625 reports angular position in the form of coarse intervals,
* so only interval change events are unmasked. Conversely, the IQS624
* reports angular position down to one degree of resolution, so wheel
* movement events are unmasked instead.
*/
if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM)
event_mask = IQS624_HALL_UI_INT_EVENT;
return regmap_update_bits(iqs62x->regmap, IQS624_HALL_UI, event_mask,
angle_en ? 0 : 0xFF);
}
static int iqs624_pos_notifier(struct notifier_block *notifier,
unsigned long event_flags, void *context)
{
struct iqs62x_event_data *event_data = context;
struct iqs624_pos_private *iqs624_pos;
struct iqs62x_core *iqs62x;
struct iio_dev *indio_dev;
u16 angle = event_data->ui_data;
s64 timestamp;
int ret;
iqs624_pos = container_of(notifier, struct iqs624_pos_private,
notifier);
indio_dev = iqs624_pos->indio_dev;
timestamp = iio_get_time_ns(indio_dev);
iqs62x = iqs624_pos->iqs62x;
if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM)
angle = event_data->interval;
mutex_lock(&iqs624_pos->lock);
if (event_flags & BIT(IQS62X_EVENT_SYS_RESET)) {
ret = iqs624_pos_angle_en(iqs62x, iqs624_pos->angle_en);
if (ret) {
dev_err(indio_dev->dev.parent,
"Failed to re-initialize device: %d\n", ret);
ret = NOTIFY_BAD;
} else {
ret = NOTIFY_OK;
}
} else if (iqs624_pos->angle_en && (angle != iqs624_pos->angle)) {
iio_push_event(indio_dev,
IIO_UNMOD_EVENT_CODE(IIO_ANGL, 0,
IIO_EV_TYPE_CHANGE,
IIO_EV_DIR_NONE),
timestamp);
iqs624_pos->angle = angle;
ret = NOTIFY_OK;
} else {
ret = NOTIFY_DONE;
}
mutex_unlock(&iqs624_pos->lock);
return ret;
}
static void iqs624_pos_notifier_unregister(void *context)
{
struct iqs624_pos_private *iqs624_pos = context;
struct iio_dev *indio_dev = iqs624_pos->indio_dev;
int ret;
ret = blocking_notifier_chain_unregister(&iqs624_pos->iqs62x->nh,
&iqs624_pos->notifier);
if (ret)
dev_err(indio_dev->dev.parent,
"Failed to unregister notifier: %d\n", ret);
}
static int iqs624_pos_angle_get(struct iqs62x_core *iqs62x, unsigned int *val)
{
int ret;
__le16 val_buf;
if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM)
return regmap_read(iqs62x->regmap, iqs62x->dev_desc->interval,
val);
ret = regmap_raw_read(iqs62x->regmap, IQS624_POS_DEG_OUT, &val_buf,
sizeof(val_buf));
if (ret)
return ret;
*val = le16_to_cpu(val_buf);
return 0;
}
static int iqs624_pos_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct iqs624_pos_private *iqs624_pos = iio_priv(indio_dev);
struct iqs62x_core *iqs62x = iqs624_pos->iqs62x;
unsigned int scale = 1;
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = iqs624_pos_angle_get(iqs62x, val);
if (ret)
return ret;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
if (iqs62x->dev_desc->prod_num == IQS625_PROD_NUM) {
ret = regmap_read(iqs62x->regmap, IQS624_INTERVAL_DIV,
&scale);
if (ret)
return ret;
}
*val = scale * IQS624_POS_SCALE1;
*val2 = IQS624_POS_SCALE2;
return IIO_VAL_FRACTIONAL;
default:
return -EINVAL;
}
}
static int iqs624_pos_read_event_config(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir)
{
struct iqs624_pos_private *iqs624_pos = iio_priv(indio_dev);
int ret;
mutex_lock(&iqs624_pos->lock);
ret = iqs624_pos->angle_en;
mutex_unlock(&iqs624_pos->lock);
return ret;
}
static int iqs624_pos_write_event_config(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
enum iio_event_type type,
enum iio_event_direction dir,
int state)
{
struct iqs624_pos_private *iqs624_pos = iio_priv(indio_dev);
struct iqs62x_core *iqs62x = iqs624_pos->iqs62x;
unsigned int val;
int ret;
mutex_lock(&iqs624_pos->lock);
ret = iqs624_pos_angle_get(iqs62x, &val);
if (ret)
goto err_mutex;
ret = iqs624_pos_angle_en(iqs62x, state);
if (ret)
goto err_mutex;
iqs624_pos->angle = val;
iqs624_pos->angle_en = state;
err_mutex:
mutex_unlock(&iqs624_pos->lock);
return ret;
}
static const struct iio_info iqs624_pos_info = {
.read_raw = &iqs624_pos_read_raw,
.read_event_config = iqs624_pos_read_event_config,
.write_event_config = iqs624_pos_write_event_config,
};
static const struct iio_event_spec iqs624_pos_events[] = {
{
.type = IIO_EV_TYPE_CHANGE,
.dir = IIO_EV_DIR_NONE,
.mask_separate = BIT(IIO_EV_INFO_ENABLE),
},
};
static const struct iio_chan_spec iqs624_pos_channels[] = {
{
.type = IIO_ANGL,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.event_spec = iqs624_pos_events,
.num_event_specs = ARRAY_SIZE(iqs624_pos_events),
},
};
static int iqs624_pos_probe(struct platform_device *pdev)
{
struct iqs62x_core *iqs62x = dev_get_drvdata(pdev->dev.parent);
struct iqs624_pos_private *iqs624_pos;
struct iio_dev *indio_dev;
int ret;
indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*iqs624_pos));
if (!indio_dev)
return -ENOMEM;
iqs624_pos = iio_priv(indio_dev);
iqs624_pos->iqs62x = iqs62x;
iqs624_pos->indio_dev = indio_dev;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->dev.parent = &pdev->dev;
indio_dev->channels = iqs624_pos_channels;
indio_dev->num_channels = ARRAY_SIZE(iqs624_pos_channels);
indio_dev->name = iqs62x->dev_desc->dev_name;
indio_dev->info = &iqs624_pos_info;
mutex_init(&iqs624_pos->lock);
iqs624_pos->notifier.notifier_call = iqs624_pos_notifier;
ret = blocking_notifier_chain_register(&iqs624_pos->iqs62x->nh,
&iqs624_pos->notifier);
if (ret) {
dev_err(&pdev->dev, "Failed to register notifier: %d\n", ret);
return ret;
}
ret = devm_add_action_or_reset(&pdev->dev,
iqs624_pos_notifier_unregister,
iqs624_pos);
if (ret)
return ret;
return devm_iio_device_register(&pdev->dev, indio_dev);
}
static struct platform_driver iqs624_pos_platform_driver = {
.driver = {
.name = "iqs624-pos",
},
.probe = iqs624_pos_probe,
};
module_platform_driver(iqs624_pos_platform_driver);
MODULE_AUTHOR("Jeff LaBundy <jeff@labundy.com>");
MODULE_DESCRIPTION("Azoteq IQS624/625 Angular Position Sensors");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:iqs624-pos");
|