On Tue, Jun 13, 2023 at 8:46 AM Kim Seer Paller
<kimseer.paller@xxxxxxxxxx> wrote:
>
> The MAX14001 is a configurable, isolated 10-bit ADC for multi-range
> binary inputs.
...
> +struct max14001_state {
> + struct spi_device *spi;
> + /*
> + * lock protect agains multiple concurrent accesses, RMW sequence, and
against
> + * SPI transfer
> + */
> + struct mutex lock;
> + int vref_mv;
> + /*
> + * DMA (thus cache coherency maintenance) requires the
> + * transfer buffers to live in their own cache lines.
> + */
> + __be16 spi_tx_buffer __aligned(IIO_DMA_MINALIGN);
> + __be16 spi_rx_buffer;
> +};
> +
> +static int max14001_read(void *context, unsigned int reg_addr, unsigned int *data)
> +{
> + struct max14001_state *st = context;
> + int ret;
> +
> + struct spi_transfer xfers[] = {
> + {
> + .tx_buf = &st->spi_tx_buffer,
> + .len = 2,
sizeof()
> + .cs_change = 1,
> + }, {
> + .rx_buf = &st->spi_rx_buffer,
> + .len = 2,
sizeof()
> + },
> + };
> +
> + st->spi_tx_buffer = bitrev16(cpu_to_be16(FIELD_PREP(MAX14001_ADDR_MASK,
> + reg_addr)));
> +
> + ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers));
> + if (ret)
> + return ret;
> +
> + *data = bitrev16(be16_to_cpu(st->spi_rx_buffer)) & MAX14001_DATA_MASK;
> +
> + return 0;
> +}
...
> +static const struct iio_chan_spec max14001_channels[] = {
> + {
> + .type = IIO_VOLTAGE,
> + .channel = 0,
Is it required?
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_SCALE),
> + }
> +};
--
With Best Regards,
Andy Shevchenko
