[PATCH v5 1/2] iio: adc: vf610: implement configurable conversion modes

[Rob Herring]

On Wed, May 27, 2015 at 7:47 AM, Stefan Agner <stefan at agner.ch> wrote:
> Support configurable conversion mode through sysfs. So far, the
> mode used was low-power, which is enabled by default now. Beside
> that, the modes normal and high-speed are selectable as well.
>
> Use the new device tree property which specifies the maximum ADC
> conversion clock frequencies. Depending on the mode used, the
> available resulting conversion frequency are calculated
> dynamically.
>
> Acked-by: Fugang Duan <B38611 at freescale.com>
> Signed-off-by: Stefan Agner <stefan at agner.ch>
> ---
>  Documentation/ABI/testing/sysfs-bus-iio-vf610      |   7 +
>  .../devicetree/bindings/iio/adc/vf610-adc.txt      |   9 ++
>  drivers/iio/adc/vf610_adc.c                        | 146 +++++++++++++++------
>  3 files changed, 120 insertions(+), 42 deletions(-)
>  create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-vf610
>
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-vf610 b/Documentation/ABI/testing/sysfs-bus-iio-vf610
> new file mode 100644
> index 0000000..ecbc1f4
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-bus-iio-vf610
> @@ -0,0 +1,7 @@
> +What:          /sys/bus/iio/devices/iio:deviceX/conversion_mode
> +KernelVersion: 4.2
> +Contact:       linux-iio at vger.kernel.org
> +Description:
> +               Specifies the hardware conversion mode used. The three
> +               available modes are "normal", "high-speed" and "low-power",
> +               where the last is the default mode.
> diff --git a/Documentation/devicetree/bindings/iio/adc/vf610-adc.txt b/Documentation/devicetree/bindings/iio/adc/vf610-adc.txt
> index 1a4a43d..3eb40e2 100644
> --- a/Documentation/devicetree/bindings/iio/adc/vf610-adc.txt
> +++ b/Documentation/devicetree/bindings/iio/adc/vf610-adc.txt
> @@ -11,6 +11,13 @@ Required properties:
>  - clock-names: Must contain "adc", matching entry in the clocks property.
>  - vref-supply: The regulator supply ADC reference voltage.
>
> +Recommended properties:
> +- fsl,adck-max-frequency: Maximum frequencies according to datasheets operating
> +  requirements. Three values are required, depending on conversion mode:
> +  - Frequency in normal mode (ADLPC=0, ADHSC=0)
> +  - Frequency in high-speed mode (ADLPC=0, ADHSC=1)
> +  - Frequency in low-power mode (ADLPC=1, ADHSC=0)

Why is this "adck" rather than "adc"?

How is this related to today's patch adding min-sample-time?

Rob