blob: 71a2c5f63b9ced2361c5fb94f255cc3c6430ba23 [file] [log] [blame]
/*
* STMicroelectronics sensors buffer library driver
*
* Copyright 2012-2013 STMicroelectronics Inc.
*
* Denis Ciocca <denis.ciocca@st.com>
*
* Licensed under the GPL-2.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/iio/iio.h>
#include <linux/iio/trigger.h>
#include <linux/interrupt.h>
#include <linux/iio/buffer.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/irqreturn.h>
#include <linux/iio/common/st_sensors.h>
int st_sensors_get_buffer_element(struct iio_dev *indio_dev, u8 *buf)
{
u8 *addr;
int i, n = 0, len;
struct st_sensor_data *sdata = iio_priv(indio_dev);
unsigned int num_data_channels = sdata->num_data_channels;
unsigned int byte_for_channel =
indio_dev->channels[0].scan_type.storagebits >> 3;
addr = kmalloc(num_data_channels, GFP_KERNEL);
if (!addr) {
len = -ENOMEM;
goto st_sensors_get_buffer_element_error;
}
for (i = 0; i < num_data_channels; i++) {
if (test_bit(i, indio_dev->active_scan_mask)) {
addr[n] = indio_dev->channels[i].address;
n++;
}
}
switch (n) {
case 1:
len = sdata->tf->read_multiple_byte(&sdata->tb, sdata->dev,
addr[0], byte_for_channel, buf, sdata->multiread_bit);
break;
case 2:
if ((addr[1] - addr[0]) == byte_for_channel) {
len = sdata->tf->read_multiple_byte(&sdata->tb,
sdata->dev, addr[0], byte_for_channel * n,
buf, sdata->multiread_bit);
} else {
u8 *rx_array;
rx_array = kmalloc(byte_for_channel * num_data_channels,
GFP_KERNEL);
if (!rx_array) {
len = -ENOMEM;
goto st_sensors_free_memory;
}
len = sdata->tf->read_multiple_byte(&sdata->tb,
sdata->dev, addr[0],
byte_for_channel * num_data_channels,
rx_array, sdata->multiread_bit);
if (len < 0) {
kfree(rx_array);
goto st_sensors_free_memory;
}
for (i = 0; i < n * num_data_channels; i++) {
if (i < n)
buf[i] = rx_array[i];
else
buf[i] = rx_array[n + i];
}
kfree(rx_array);
len = byte_for_channel * n;
}
break;
case 3:
len = sdata->tf->read_multiple_byte(&sdata->tb, sdata->dev,
addr[0], byte_for_channel * num_data_channels,
buf, sdata->multiread_bit);
break;
default:
len = -EINVAL;
goto st_sensors_free_memory;
}
if (len != byte_for_channel * n) {
len = -EIO;
goto st_sensors_free_memory;
}
st_sensors_free_memory:
kfree(addr);
st_sensors_get_buffer_element_error:
return len;
}
EXPORT_SYMBOL(st_sensors_get_buffer_element);
irqreturn_t st_sensors_trigger_handler(int irq, void *p)
{
int len;
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct st_sensor_data *sdata = iio_priv(indio_dev);
len = st_sensors_get_buffer_element(indio_dev, sdata->buffer_data);
if (len < 0)
goto st_sensors_get_buffer_element_error;
if (indio_dev->scan_timestamp)
*(s64 *)((u8 *)sdata->buffer_data +
ALIGN(len, sizeof(s64))) = pf->timestamp;
iio_push_to_buffers(indio_dev, sdata->buffer_data);
st_sensors_get_buffer_element_error:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
EXPORT_SYMBOL(st_sensors_trigger_handler);
MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
MODULE_DESCRIPTION("STMicroelectronics ST-sensors buffer");
MODULE_LICENSE("GPL v2");