1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * STMicroelectronics sensors buffer library driver |
4 | * |
5 | * Copyright 2012-2013 STMicroelectronics Inc. |
6 | * |
7 | * Denis Ciocca <denis.ciocca@st.com> |
8 | */ |
9 | |
10 | #include <linux/kernel.h> |
11 | #include <linux/iio/iio.h> |
12 | #include <linux/iio/trigger.h> |
13 | #include <linux/interrupt.h> |
14 | #include <linux/iio/buffer.h> |
15 | #include <linux/iio/trigger_consumer.h> |
16 | #include <linux/irqreturn.h> |
17 | #include <linux/regmap.h> |
18 | |
19 | #include <linux/iio/common/st_sensors.h> |
20 | |
21 | |
22 | static int st_sensors_get_buffer_element(struct iio_dev *indio_dev, u8 *buf) |
23 | { |
24 | struct st_sensor_data *sdata = iio_priv(indio_dev); |
25 | unsigned int num_data_channels = sdata->num_data_channels; |
26 | int i; |
27 | |
28 | for_each_set_bit(i, indio_dev->active_scan_mask, num_data_channels) { |
29 | const struct iio_chan_spec *channel = &indio_dev->channels[i]; |
30 | unsigned int bytes_to_read = |
31 | DIV_ROUND_UP(channel->scan_type.realbits + |
32 | channel->scan_type.shift, 8); |
33 | unsigned int storage_bytes = |
34 | channel->scan_type.storagebits >> 3; |
35 | |
36 | buf = PTR_ALIGN(buf, storage_bytes); |
37 | if (regmap_bulk_read(map: sdata->regmap, reg: channel->address, |
38 | val: buf, val_count: bytes_to_read) < 0) |
39 | return -EIO; |
40 | |
41 | /* Advance the buffer pointer */ |
42 | buf += storage_bytes; |
43 | } |
44 | |
45 | return 0; |
46 | } |
47 | |
48 | irqreturn_t st_sensors_trigger_handler(int irq, void *p) |
49 | { |
50 | int len; |
51 | struct iio_poll_func *pf = p; |
52 | struct iio_dev *indio_dev = pf->indio_dev; |
53 | struct st_sensor_data *sdata = iio_priv(indio_dev); |
54 | s64 timestamp; |
55 | |
56 | /* |
57 | * If we do timestamping here, do it before reading the values, because |
58 | * once we've read the values, new interrupts can occur (when using |
59 | * the hardware trigger) and the hw_timestamp may get updated. |
60 | * By storing it in a local variable first, we are safe. |
61 | */ |
62 | if (iio_trigger_using_own(indio_dev)) |
63 | timestamp = sdata->hw_timestamp; |
64 | else |
65 | timestamp = iio_get_time_ns(indio_dev); |
66 | |
67 | len = st_sensors_get_buffer_element(indio_dev, buf: sdata->buffer_data); |
68 | if (len < 0) |
69 | goto st_sensors_get_buffer_element_error; |
70 | |
71 | iio_push_to_buffers_with_timestamp(indio_dev, data: sdata->buffer_data, |
72 | timestamp); |
73 | |
74 | st_sensors_get_buffer_element_error: |
75 | iio_trigger_notify_done(trig: indio_dev->trig); |
76 | |
77 | return IRQ_HANDLED; |
78 | } |
79 | EXPORT_SYMBOL_NS(st_sensors_trigger_handler, IIO_ST_SENSORS); |
80 | |