Re: [PATCH v17 3/7] usb: core: hcd: Create platform devices for onboard hubs in probe()

From: Doug Anderson <dianders@chromium.org>
To: Matthias Kaehlcke <mka@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Alan Stern <stern@rowland.harvard.edu>,
	Rob Herring <robh+dt@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Mathias Nyman <mathias.nyman@intel.com>,
	Felipe Balbi <balbi@kernel.org>,
	linux-kernel@vger.kernel.org,
	Krzysztof Kozlowski <krzk@kernel.org>,
	Stephen Boyd <swboyd@chromium.org>,
	Peter Chen <peter.chen@kernel.org>,
	linux-usb@vger.kernel.org, devicetree@vger.kernel.org,
	Roger Quadros <rogerq@kernel.org>,
	Michal Simek <michal.simek@xilinx.com>,
	Ravi Chandra Sadineni <ravisadineni@chromium.org>,
	Bastien Nocera <hadess@hadess.net>,
	Andrey Konovalov <andreyknvl@gmail.com>,
	Kishon Vijay Abraham I <kishon@ti.com>, Li Jun <jun.li@nxp.com>,
	Peter Chen <peter.chen@nxp.com>, Sasha Levin <sashal@kernel.org>
Subject: Re: [PATCH v17 3/7] usb: core: hcd: Create platform devices for onboard hubs in probe()
Date: Wed, 17 Nov 2021 16:03:25 -0800	[thread overview]
Message-ID: <CAD=FV=VcAdSWWVykGrw2r5BFMe4Esotb+ieggczcrY2TH-4VSA@mail.gmail.com> (raw)
In-Reply-To: <20211116120642.v17.3.I7a3a7d9d2126c34079b1cab87aa0b2ec3030f9b7@changeid>

Hi,

On Tue, Nov 16, 2021 at 12:07 PM Matthias Kaehlcke <mka@chromium.org> wrote:
>
> Call onboard_hub_create/destroy_pdevs() from usb_add/remove_hcd()
> for primary HCDs to create/destroy platform devices for onboard
> USB hubs that may be connected to the root hub of the controller.
> These functions are a NOP unless CONFIG_USB_ONBOARD_HUB=y/m.
>
> Also add a field to struct usb_hcd to keep track of the onboard hub
> platform devices that are owned by the HCD.
>
> Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
> ---
>
> Changes in v17:
> - create the platform devices in the generic HCD code instead of
>   the xhci_platform driver
> - updated subject and commit message to reflect the above change
> - dropped initialization of platform device list, which is now
>   done in onboard_hub_create_pdevs()
>
> Changes in v16:
> - none
>
> Changes in v15:
> - none
>
> Changes in v14:
> - none
>
> Changes in v13:
> - added comment for 'depends on USB_ONBOARD_HUB || !USB_ONBOARD_HUB'
>   construct
>
> Changes in v12:
> - none
>
> Changes in v11:
> - use onboard_hub_create/destroy_pdevs() to support multiple onboard
>   hubs that are connected to the same root hub
> - moved field/list to keep track of platform devices from struct
>   usb_hcd to struct xhci_hcd
> - updated commit message
>
> Changes in v10:
> - none
>
> Changes in v9:
> - added dependency on USB_ONBOARD_HUB (or !!USB_ONBOARD_HUB) to
>   USB_XHCI_PLATFORM
>
> Changes in v8:
> - none
>
> Changes in v7:
> - none
>
> Changes in v6:
> - none
>
> Changes in v5:
> - patch added to the series
>
>  drivers/usb/core/hcd.c  | 6 ++++++
>  include/linux/usb/hcd.h | 1 +
>  2 files changed, 7 insertions(+)

This looks sane to me, so:

Reviewed-by: Douglas Anderson <dianders@chromium.org>

That being said, I don't know these functions and can't say with any
authority that this is the "right" place to put the
onboard_hub_create_pdevs() and onboard_hub_destroy_pdevs(). I'm
assuming that Alan, Greg, or someone else on this CC list will
scrutinize that more closely and make sure where Matthias picked is
OK.

-Doug