Subject: Re: [PATCH v8 2/7] nfc: pn532: Add uart phy docs and rename it

From: Rob Herring <[email-masked]>
Date: Fri, 27 Sep 2019 10:52:09 -0500

On Thu, Sep 19, 2019 at 11:16:39AM +0200, Lars Poeschel wrote:
> This adds documentation about the uart phy to the pn532 binding doc. As
> the filename "pn533-i2c.txt" is not appropriate any more, rename it to
> the more general "pn532.txt".
> This also documents the deprecation of the compatible strings ending
> with "...-i2c".
> 
> Cc: Johan Hovold <[email-masked]>
> Cc: Simon Horman <[email-masked]>
> Signed-off-by: Lars Poeschel <[email-masked]>
> ---
> Changes in v8:
> - Update existing binding doc instead of adding a new one:
>   - Add uart phy example
>   - Add general "pn532" compatible string
>   - Deprecate "...-i2c" compatible strings
>   - Rename file to a more general filename
> - Intentionally drop Rob's Reviewed-By as I guess this rather big change
>   requires a new review
> 
> Changes in v7:
> - Accidentally lost Rob's Reviewed-By
> 
> Changes in v6:
> - Rebased the patch series on v5.3-rc5
> - Picked up Rob's Reviewed-By
> 
> Changes in v4:
> - Add documentation about reg property in case of i2c
> 
> Changes in v3:
> - seperate binding doc instead of entry in trivial-devices.txt
> 
>  .../devicetree/bindings/net/nfc/pn532.txt     | 46 +++++++++++++++++++
>  .../devicetree/bindings/net/nfc/pn533-i2c.txt | 29 ------------
>  2 files changed, 46 insertions(+), 29 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/net/nfc/pn532.txt
>  delete mode 100644 Documentation/devicetree/bindings/net/nfc/pn533-i2c.txt

In the future, use '-M' option (I recommend making this the default).

> 
> diff --git a/Documentation/devicetree/bindings/net/nfc/pn532.txt b/Documentation/devicetree/bindings/net/nfc/pn532.txt
> new file mode 100644
> index 000000000000..f0591f160bee
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/nfc/pn532.txt
> @@ -0,0 +1,46 @@
> +* NXP Semiconductors PN532 NFC Controller
> +
> +Required properties:
> +- compatible: Should be
> +    - "nxp,pn532" Place a node with this inside the devicetree node of the bus
> +                  where the NFC chip is connected to.
> +                  Currently the kernel has phy bindings for uart and i2c.
> +    - "nxp,pn532-i2c" (DEPRECATED) only works for the i2c binding.
> +    - "nxp,pn533-i2c" (DEPRECATED) only works for the i2c binding.

No more pm533 support?

> +
> +Required properties if connected on i2c:
> +- clock-frequency: I²C work frequency.
> +- reg: for the I²C bus address. This is fixed at 0x24 for the PN532.
> +- interrupts: GPIO interrupt to which the chip is connected

UART attached case has no irq? I guess it could just start sending 
data...

> +
> +Optional SoC Specific Properties:
> +- pinctrl-names: Contains only one value - "default".
> +- pintctrl-0: Specifies the pin control groups used for this controller.
> +
> +Example (for ARM-based BeagleBone with PN532 on I2C2):
> +
> +&i2c2 {
> +
> +
> +	pn532: pn532@24 {

nfc@24

> +
> +		compatible = "nxp,pn532";
> +
> +		reg = <0x24>;
> +		clock-frequency = <400000>;
> +
> +		interrupt-parent = <&gpio1>;
> +		interrupts = <17 IRQ_TYPE_EDGE_FALLING>;
> +
> +	};
> +};
> +
> +Example (for PN532 connected via uart):
> +
> +uart4: serial@49042000 {
> +        compatible = "ti,omap3-uart";
> +
> +        pn532: nfc {
> +                compatible = "nxp,pn532";
> +        };
> +};