diff options
Diffstat (limited to 'drivers/staging/iio/imu/adis16400_ring.c')
-rw-r--r-- | drivers/staging/iio/imu/adis16400_ring.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/drivers/staging/iio/imu/adis16400_ring.c b/drivers/staging/iio/imu/adis16400_ring.c index 66a91ada954..5d94cdc2ea2 100644 --- a/drivers/staging/iio/imu/adis16400_ring.c +++ b/drivers/staging/iio/imu/adis16400_ring.c @@ -97,6 +97,54 @@ static void adis16400_poll_func_th(struct iio_dev *indio_dev) */ } +/** + * adis16400_spi_read_burst() - read all data registers + * @dev: device associated with child of actual device (iio_dev or iio_trig) + * @rx: somewhere to pass back the value read (min size is 24 bytes) + **/ +static int adis16400_spi_read_burst(struct device *dev, u8 *rx) +{ + struct spi_message msg; + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct adis16400_state *st = iio_dev_get_devdata(indio_dev); + u32 old_speed_hz = st->us->max_speed_hz; + int ret; + + struct spi_transfer xfers[] = { + { + .tx_buf = st->tx, + .bits_per_word = 8, + .len = 2, + .cs_change = 0, + }, { + .rx_buf = rx, + .bits_per_word = 8, + .len = 24, + .cs_change = 1, + }, + }; + + mutex_lock(&st->buf_lock); + st->tx[0] = ADIS16400_READ_REG(ADIS16400_GLOB_CMD); + st->tx[1] = 0; + + spi_message_init(&msg); + spi_message_add_tail(&xfers[0], &msg); + spi_message_add_tail(&xfers[1], &msg); + + st->us->max_speed_hz = min(ADIS16400_SPI_BURST, old_speed_hz); + spi_setup(st->us); + + ret = spi_sync(st->us, &msg); + if (ret) + dev_err(&st->us->dev, "problem when burst reading"); + + st->us->max_speed_hz = old_speed_hz; + spi_setup(st->us); + mutex_unlock(&st->buf_lock); + return ret; +} + /* Whilst this makes a lot of calls to iio_sw_ring functions - it is to device * specific to be rolled into the core. */ |