diff options
Diffstat (limited to 'drivers/iio/dac/ad5504.c')
| -rw-r--r-- | drivers/iio/dac/ad5504.c | 40 |
1 files changed, 20 insertions, 20 deletions
diff --git a/drivers/iio/dac/ad5504.c b/drivers/iio/dac/ad5504.c index 6cd0dd60c17..d44c8f5fade 100644 --- a/drivers/iio/dac/ad5504.c +++ b/drivers/iio/dac/ad5504.c @@ -47,14 +47,16 @@ * @vref_mv: actual reference voltage used * @pwr_down_mask power down mask * @pwr_down_mode current power down mode + * @data: transfer buffer */ - struct ad5504_state { struct spi_device *spi; struct regulator *reg; unsigned short vref_mv; unsigned pwr_down_mask; unsigned pwr_down_mode; + + __be16 data[2] ____cacheline_aligned; }; /** @@ -66,31 +68,29 @@ enum ad5504_supported_device_ids { ID_AD5501, }; -static int ad5504_spi_write(struct spi_device *spi, u8 addr, u16 val) +static int ad5504_spi_write(struct ad5504_state *st, u8 addr, u16 val) { - __be16 tmp = cpu_to_be16(AD5504_CMD_WRITE | - AD5504_ADDR(addr) | + st->data[0] = cpu_to_be16(AD5504_CMD_WRITE | AD5504_ADDR(addr) | (val & AD5504_RES_MASK)); - return spi_write(spi, (u8 *)&tmp, 2); + return spi_write(st->spi, &st->data[0], 2); } -static int ad5504_spi_read(struct spi_device *spi, u8 addr) +static int ad5504_spi_read(struct ad5504_state *st, u8 addr) { - __be16 tmp = cpu_to_be16(AD5504_CMD_READ | AD5504_ADDR(addr)); - __be16 val; int ret; - struct spi_transfer t = { - .tx_buf = &tmp, - .rx_buf = &val, - .len = 2, - }; - ret = spi_sync_transfer(spi, &t, 1); - + struct spi_transfer t = { + .tx_buf = &st->data[0], + .rx_buf = &st->data[1], + .len = 2, + }; + + st->data[0] = cpu_to_be16(AD5504_CMD_READ | AD5504_ADDR(addr)); + ret = spi_sync_transfer(st->spi, &t, 1); if (ret < 0) return ret; - return be16_to_cpu(val) & AD5504_RES_MASK; + return be16_to_cpu(st->data[1]) & AD5504_RES_MASK; } static int ad5504_read_raw(struct iio_dev *indio_dev, @@ -104,7 +104,7 @@ static int ad5504_read_raw(struct iio_dev *indio_dev, switch (m) { case IIO_CHAN_INFO_RAW: - ret = ad5504_spi_read(st->spi, chan->address); + ret = ad5504_spi_read(st, chan->address); if (ret < 0) return ret; @@ -133,7 +133,7 @@ static int ad5504_write_raw(struct iio_dev *indio_dev, if (val >= (1 << chan->scan_type.realbits) || val < 0) return -EINVAL; - return ad5504_spi_write(st->spi, chan->address, val); + return ad5504_spi_write(st, chan->address, val); default: ret = -EINVAL; } @@ -197,12 +197,12 @@ static ssize_t ad5504_write_dac_powerdown(struct iio_dev *indio_dev, else st->pwr_down_mask &= ~(1 << chan->channel); - ret = ad5504_spi_write(st->spi, AD5504_ADDR_CTRL, + ret = ad5504_spi_write(st, AD5504_ADDR_CTRL, AD5504_DAC_PWRDWN_MODE(st->pwr_down_mode) | AD5504_DAC_PWR(st->pwr_down_mask)); /* writes to the CTRL register must be followed by a NOOP */ - ad5504_spi_write(st->spi, AD5504_ADDR_NOOP, 0); + ad5504_spi_write(st, AD5504_ADDR_NOOP, 0); return ret ? ret : len; } |