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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * STMicroelectronics sensors buffer library driver4 *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 22static 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(sdata->regmap, channel->address,38 buf, bytes_to_read) < 0)39 return -EIO;40 41 /* Advance the buffer pointer */42 buf += storage_bytes;43 }44 45 return 0;46}47 48irqreturn_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, because58 * once we've read the values, new interrupts can occur (when using59 * 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 else65 timestamp = iio_get_time_ns(indio_dev);66 67 len = st_sensors_get_buffer_element(indio_dev, 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, sdata->buffer_data,72 timestamp);73 74st_sensors_get_buffer_element_error:75 iio_trigger_notify_done(indio_dev->trig);76 77 return IRQ_HANDLED;78}79EXPORT_SYMBOL_NS(st_sensors_trigger_handler, IIO_ST_SENSORS);80