Subject: Re: [PATCH RFC 19/28] net: dsa: bcm_sf2: make it a real platform driver

From: Florian Fainelli <[email-masked]>
Date: Wed, 23 Dec 2015 12:32:40 -0800

Hi Andrew,

Le 23/12/2015 04:56, Andrew Lunn a écrit :
> diff --git a/Documentation/devicetree/bindings/net/dsa/broadcom.txt b/Documentation/devicetree/bindings/net/dsa/broadcom.txt
> new file mode 100644
> index 000000000000..bd92be0ef2c8
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/dsa/broadcom.txt
> @@ -0,0 +1,48 @@
> +* Broadcom Starfighter 2 integrated switch device
> +
> +Required properties:
> +
> +- compatible: should be "brcm,brcm-sf2"
> +- reg: addresses and length of the register sets for the device, must be 6
> +  pairs of register addresses and lengths
> +- interrupts: interrupts for the devices, must be two interrupts
> +
> +Optional properties:
> +
> +- reg-names: litteral names for the device base register addresses,
> +  when present must be: "core", "reg", "intrl2_0", "intrl2_1", "fcb",
> +  "acb"

These are in fact mandatory properties.

> +
> +- interrupt-names: litternal names for the device interrupt lines,
> +  when present must be: "switch_0" and "switch_1"

Likewise

> +
> +- brcm,num-gphy: specify the maximum number of integrated gigabit PHYs
> +  in the switch

Likewise

> +
> +- brcm,num-rgmii-ports: specify the maximum number of RGMII interfaces
> +  supported by the switch
> +
> +- brcm,fcb-pause-override: boolean property, if present indicates that
> +  the switch supports Failover Control Block pause override capability
> +
> +- brcm,acb-packets-inflight: boolean property, if present indicates
> +  that the switch Admission Control Block supports reporting the
> +  number of packets in-flight in a switch queue

All of these above are indeed optional.

Having to introduce a new binding for this driver to be converted is a
major deal breaker, the platforms I use have a frozen, yet wrongly
specified Device Tree binding, but still, we need to keep backward
compatibility with it.

My initial attempt, if you remove the part where I tried to convert
every switch driver into a PHY device handled that:

https://github.com/ffainelli/linux/commit/287fc1b33cdd6155c507a95531fd820a5c6dbaf4

Since we have dsa_of_probe(), that alone should be enough to allow us to
maintain a dsa_platform_data structure along with the old binding. This
is not a whole lot different from your patch 13.

Thanks!
-- 
Florian