Re: [PATCH v3 1/1] add support for Seagate BlackArmor NAS220

From: Sebastian Hesselbarth
Date: Thu Dec 25 2014 - 08:43:23 EST


On 25.12.2014 14:31, Andrew Lunn wrote:
On Thu, Dec 25, 2014 at 02:08:12PM +0100, Sebastian Hesselbarth wrote:
+ status = "okay";
+ };
+
+ sata@80000 {
+ status = "okay";
+ nr-ports = <2>;

I need some update from the other mvebu guys here: Do we have SATA
PHY nodes in v3.19 for Kirkwood already? If so, please update to the
new binding.

Hi Sebastian

I'm not sure what you mean here. The binding Documentation says:

I was hoping that using phys/phy-names would allow us to get rid of
nr-ports property. I haven't checked the corresponding code and likely
will not before next year, but we should try to get rid of the nr-ports
property completely.

Required Properties:
- compatibility : "marvell,orion-sata" or "marvell,armada-370-sata"
- reg : Address range of controller
- interrupts : Interrupt controller is using
- nr-ports : Number of SATA ports in use.

Optional Properties:
- phys : List of phandles to sata phys
- phy-names : Should be "0", "1", etc, one number per phandle

The optional phys/phy-names have just been added to
kirkwood-6192.dtsi.

Yeah, saw that patch after the review.. and my understanding of the
phys/phy-names properties is that
(a) they allow to count the number of _available_ ports
(b) they allow to determine the number of _used_ ports
(c) they allow to e.g. disable port 0 but enable port 1

while nr-ports only allows (a). You can derive (b) only if you use
the first out of two but you cannot do (c) with nr-ports.

Which is why we introduced the phys/phy-names properties.

Sebastian

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