diff options
Diffstat (limited to 'drivers/iio/common/st_sensors/st_sensors_buffer.c')
-rw-r--r-- | drivers/iio/common/st_sensors/st_sensors_buffer.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/drivers/iio/common/st_sensors/st_sensors_buffer.c b/drivers/iio/common/st_sensors/st_sensors_buffer.c new file mode 100644 index 000000000000..09b236d6ee89 --- /dev/null +++ b/drivers/iio/common/st_sensors/st_sensors_buffer.c @@ -0,0 +1,116 @@ +/* + * 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) +{ + int i, n = 0, len; + u8 addr[ST_SENSORS_NUMBER_DATA_CHANNELS]; + struct st_sensor_data *sdata = iio_priv(indio_dev); + + for (i = 0; i < ST_SENSORS_NUMBER_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], ST_SENSORS_BYTE_FOR_CHANNEL, buf, + sdata->multiread_bit); + break; + case 2: + if ((addr[1] - addr[0]) == ST_SENSORS_BYTE_FOR_CHANNEL) { + len = sdata->tf->read_multiple_byte(&sdata->tb, + sdata->dev, addr[0], + ST_SENSORS_BYTE_FOR_CHANNEL*n, + buf, sdata->multiread_bit); + } else { + u8 rx_array[ST_SENSORS_BYTE_FOR_CHANNEL* + ST_SENSORS_NUMBER_DATA_CHANNELS]; + len = sdata->tf->read_multiple_byte(&sdata->tb, + sdata->dev, addr[0], + ST_SENSORS_BYTE_FOR_CHANNEL* + ST_SENSORS_NUMBER_DATA_CHANNELS, + rx_array, sdata->multiread_bit); + if (len < 0) + goto read_data_channels_error; + + for (i = 0; i < n * ST_SENSORS_NUMBER_DATA_CHANNELS; + i++) { + if (i < n) + buf[i] = rx_array[i]; + else + buf[i] = rx_array[n + i]; + } + len = ST_SENSORS_BYTE_FOR_CHANNEL*n; + } + break; + case 3: + len = sdata->tf->read_multiple_byte(&sdata->tb, sdata->dev, + addr[0], ST_SENSORS_BYTE_FOR_CHANNEL* + ST_SENSORS_NUMBER_DATA_CHANNELS, + buf, sdata->multiread_bit); + break; + default: + len = -EINVAL; + goto read_data_channels_error; + } + if (len != ST_SENSORS_BYTE_FOR_CHANNEL*n) { + len = -EIO; + goto read_data_channels_error; + } + +read_data_channels_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"); |