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
|
/*
* STMicroelectronics hts221 sensor driver
*
* Copyright 2016 STMicroelectronics Inc.
*
* Lorenzo Bianconi <lorenzo.bianconi@st.com>
*
* Licensed under the GPL-2.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/irqreturn.h>
#include <linux/iio/iio.h>
#include <linux/iio/trigger.h>
#include <linux/iio/events.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/buffer.h>
#include "hts221.h"
#define HTS221_REG_STATUS_ADDR 0x27
#define HTS221_RH_DRDY_MASK BIT(1)
#define HTS221_TEMP_DRDY_MASK BIT(0)
static int hts221_trig_set_state(struct iio_trigger *trig, bool state)
{
struct iio_dev *iio_dev = iio_trigger_get_drvdata(trig);
struct hts221_hw *hw = iio_priv(iio_dev);
return hts221_config_drdy(hw, state);
}
static const struct iio_trigger_ops hts221_trigger_ops = {
.owner = THIS_MODULE,
.set_trigger_state = hts221_trig_set_state,
};
static irqreturn_t hts221_trigger_handler_thread(int irq, void *private)
{
struct hts221_hw *hw = private;
u8 status;
int err;
err = hw->tf->read(hw->dev, HTS221_REG_STATUS_ADDR, sizeof(status),
&status);
if (err < 0)
return IRQ_HANDLED;
/*
* H_DA bit (humidity data available) is routed to DRDY line.
* Humidity sample is computed after temperature one.
* Here we can assume data channels are both available if H_DA bit
* is set in status register
*/
if (!(status & HTS221_RH_DRDY_MASK))
return IRQ_NONE;
iio_trigger_poll_chained(hw->trig);
return IRQ_HANDLED;
}
int hts221_allocate_trigger(struct hts221_hw *hw)
{
struct iio_dev *iio_dev = iio_priv_to_dev(hw);
unsigned long irq_type;
int err;
irq_type = irqd_get_trigger_type(irq_get_irq_data(hw->irq));
switch (irq_type) {
case IRQF_TRIGGER_HIGH:
case IRQF_TRIGGER_RISING:
break;
default:
dev_info(hw->dev,
"mode %lx unsupported, using IRQF_TRIGGER_RISING\n",
irq_type);
irq_type = IRQF_TRIGGER_RISING;
break;
}
err = devm_request_threaded_irq(hw->dev, hw->irq, NULL,
hts221_trigger_handler_thread,
irq_type | IRQF_ONESHOT,
hw->name, hw);
if (err) {
dev_err(hw->dev, "failed to request trigger irq %d\n",
hw->irq);
return err;
}
hw->trig = devm_iio_trigger_alloc(hw->dev, "%s-trigger",
iio_dev->name);
if (!hw->trig)
return -ENOMEM;
iio_trigger_set_drvdata(hw->trig, iio_dev);
hw->trig->ops = &hts221_trigger_ops;
hw->trig->dev.parent = hw->dev;
iio_dev->trig = iio_trigger_get(hw->trig);
return devm_iio_trigger_register(hw->dev, hw->trig);
}
static int hts221_buffer_preenable(struct iio_dev *iio_dev)
{
return hts221_power_on(iio_priv(iio_dev));
}
static int hts221_buffer_postdisable(struct iio_dev *iio_dev)
{
return hts221_power_off(iio_priv(iio_dev));
}
static const struct iio_buffer_setup_ops hts221_buffer_ops = {
.preenable = hts221_buffer_preenable,
.postenable = iio_triggered_buffer_postenable,
.predisable = iio_triggered_buffer_predisable,
.postdisable = hts221_buffer_postdisable,
};
static irqreturn_t hts221_buffer_handler_thread(int irq, void *p)
{
u8 buffer[ALIGN(2 * HTS221_DATA_SIZE, sizeof(s64)) + sizeof(s64)];
struct iio_poll_func *pf = p;
struct iio_dev *iio_dev = pf->indio_dev;
struct hts221_hw *hw = iio_priv(iio_dev);
struct iio_chan_spec const *ch;
int err;
/* humidity data */
ch = &iio_dev->channels[HTS221_SENSOR_H];
err = hw->tf->read(hw->dev, ch->address, HTS221_DATA_SIZE,
buffer);
if (err < 0)
goto out;
/* temperature data */
ch = &iio_dev->channels[HTS221_SENSOR_T];
err = hw->tf->read(hw->dev, ch->address, HTS221_DATA_SIZE,
buffer + HTS221_DATA_SIZE);
if (err < 0)
goto out;
iio_push_to_buffers_with_timestamp(iio_dev, buffer,
iio_get_time_ns(iio_dev));
out:
iio_trigger_notify_done(hw->trig);
return IRQ_HANDLED;
}
int hts221_allocate_buffers(struct hts221_hw *hw)
{
return devm_iio_triggered_buffer_setup(hw->dev, iio_priv_to_dev(hw),
NULL, hts221_buffer_handler_thread,
&hts221_buffer_ops);
}
MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi@st.com>");
MODULE_DESCRIPTION("STMicroelectronics hts221 buffer driver");
MODULE_LICENSE("GPL v2");
|
