Re: [PATCH v4 2/5] Documentation: devicetree: Add DT bindings to eeprom_93xx46 driver.

[Vladimir Zapolskiy <vz@mleia.com>]

Hi Cory,

On 10.12.2015 06:00, Cory Tusar wrote:
> This commit documents bindings to be added to the eeprom_93xx46 driver
> which will allow:
> 
>   - Device word size and read-only attributes to be specified.
>   - A device-specific compatible string for use with Atmel AT93C46D
>     EEPROMs.
>   - Specifying a GPIO line to function as a 'select' or 'enable' signal
>     prior to accessing the EEPROM.
> 
> Signed-off-by: Cory Tusar <cory.tusar@pid1solutions.com>
> Acked-by: Rob Herring <robh@kernel.org>
> Tested-by: Chris Healy <chris.healy@zii.aero>
> ---
>  .../devicetree/bindings/misc/eeprom-93xx46.txt     | 25 ++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/misc/eeprom-93xx46.txt b/Documentation/devicetree/bindings/misc/eeprom-93xx46.txt
> new file mode 100644
> index 0000000..a8ebb46
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/misc/eeprom-93xx46.txt
> @@ -0,0 +1,25 @@
> +EEPROMs (SPI) compatible with Microchip Technology 93xx46 family.
> +
> +Required properties:
> +- compatible : shall be one of:
> +    "atmel,at93c46d"
> +    "eeprom-93xx46"

the second compatible property value is not recommended by ePAPR, I would
suggest to remove it from here and from the example below.

But I see that Rob acked this change though...

> +- data-size : number of data bits per word (either 8 or 16)
> +
> +Optional properties:
> +- read-only : parameter-less property which disables writes to the EEPROM
> +- select-gpios : if present, specifies the GPIO that will be asserted prior to
> +  each access to the EEPROM (e.g. for SPI bus multiplexing)
> +
> +Property rules described in Documentation/devicetree/bindings/spi/spi-bus.txt
> +apply.  In particular, "reg" and "spi-max-frequency" properties must be given.
> +
> +Example:
> +	eeprom@0 {
> +		compatible = "eeprom-93xx46";
> +		reg = <0>;
> +		spi-max-frequency = <1000000>;
> +		spi-cs-high;
> +		data-size = <8>;
> +		select-gpios = <&gpio4 4 GPIO_ACTIVE_HIGH>;
> +	};
> 

--
With best wishes,
Vladimir