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Date:   Wed, 27 Oct 2021 11:58:57 -0500
From:   Bjorn Helgaas <helgaas@kernel.org>
To:     Jim Quinlan <james.quinlan@broadcom.com>
Cc:     Rob Herring <robh@kernel.org>, Jim Quinlan <jim2101024@gmail.com>,
        "open list:PCI NATIVE HOST BRIDGE AND ENDPOINT DRIVERS" 
        <linux-pci@vger.kernel.org>,
        Nicolas Saenz Julienne <nsaenz@kernel.org>,
        Mark Brown <broonie@kernel.org>,
        "maintainer:BROADCOM BCM7XXX ARM ARCHITECTURE" 
        <bcm-kernel-feedback-list@broadcom.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Saenz Julienne <nsaenzjulienne@suse.de>,
        "moderated list:BROADCOM BCM7XXX ARM ARCHITECTURE" 
        <linux-arm-kernel@lists.infradead.org>,
        "moderated list:BROADCOM BCM2711/BCM2835 ARM ARCHITECTURE" 
        <linux-rpi-kernel@lists.infradead.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v5 1/6] dt-bindings: PCI: Add bindings for Brcmstb EP
 voltage regulators
Message-ID: <20211027165857.GA229979@bhelgaas>
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On Tue, Oct 26, 2021 at 05:27:32PM -0400, Jim Quinlan wrote:

> I don't think it matters but our PCIe controllers only have a single
> root port.

Just to kibitz, and I don't know anything about the DT binding under
discussion here, but I would prefer if DTs and drivers did not have
the "single root port" assumption baked deeply in them.

I expect some controllers to support multiple root ports, and it would
be really nice if the DTs and drivers all had similar structures with
the single-root-port controllers just being the N=1 case.

For example, some drivers put their per-root port stuff in
*_add_pcie_port() functions, which I think is a nice way to do it
because it leaves the door open for calling *_add_pcie_port() in a
loop.

Ironically, the only driver I see that looks like it currently
supports multiple root ports is pci-mvebu.c, and it doesn't have an
_add_pcie_port() function.

Having this sort of consistent structure and naming across drivers is
a huge help for ongoing maintenance.

Bjorn