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From: Rob Herring <robh@kernel.org>
Date: Fri, 12 Apr 2024 07:54:32 -0500
Message-ID: <CAL_JsqKRVVNzgQk6PETfJ9RrDuzT1CTjHWW02Twc_T4C82t__Q@mail.gmail.com>
Subject: Re: [PATCH v3 2/2] of: dynamic: Fix overlayed devices not probing
 because of fw_devlink
To: Saravana Kannan <saravanak@google.com>
Cc: Herve Codina <herve.codina@bootlin.com>, 
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>, "Rafael J. Wysocki" <rafael@kernel.org>, 
	Shawn Guo <shawnguo@kernel.org>, Sascha Hauer <s.hauer@pengutronix.de>, 
	Pengutronix Kernel Team <kernel@pengutronix.de>, Fabio Estevam <festevam@gmail.com>, 
	Wolfram Sang <wsa+renesas@sang-engineering.com>, Mark Brown <broonie@kernel.org>, 
	Len Brown <lenb@kernel.org>, Andy Shevchenko <andriy.shevchenko@linux.intel.com>, 
	Daniel Scally <djrscally@gmail.com>, Heikki Krogerus <heikki.krogerus@linux.intel.com>, 
	Sakari Ailus <sakari.ailus@linux.intel.com>, Geert Uytterhoeven <geert+renesas@glider.be>, 
	kernel-team@android.com, Wolfram Sang <wsa@kernel.org>, linux-kernel@vger.kernel.org, 
	imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, 
	linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, 
	linux-spi@vger.kernel.org, linux-acpi@vger.kernel.org
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On Thu, Apr 11, 2024 at 6:56=E2=80=AFPM Saravana Kannan <saravanak@google.c=
om> wrote:
>
> When an overlay is applied, if the target device has already probed
> successfully and bound to a device, then some of the fw_devlink logic
> that ran when the device was probed needs to be rerun. This allows newly
> created dangling consumers of the overlayed device tree nodes to be
> moved to become consumers of the target device.
>
> Fixes: 1a50d9403fb9 ("treewide: Fix probing of devices in DT overlays")
> Reported-by: Herve Codina <herve.codina@bootlin.com>
> Closes: https://lore.kernel.org/lkml/CAMuHMdXEnSD4rRJ-o90x4OprUacN_rJgyo8=
x6=3D9F9rZ+-KzjOg@mail.gmail.com/
> Closes: https://lore.kernel.org/all/20240221095137.616d2aaa@bootlin.com/
> Closes: https://lore.kernel.org/lkml/20240312151835.29ef62a0@bootlin.com/
> Signed-off-by: Saravana Kannan <saravanak@google.com>
> ---
>  drivers/base/core.c    | 76 +++++++++++++++++++++++++++++++++++++-----
>  drivers/of/overlay.c   | 15 +++++++++
>  include/linux/fwnode.h |  1 +
>  3 files changed, 83 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/base/core.c b/drivers/base/core.c
> index 5f4e03336e68..1a646f393dd7 100644
> --- a/drivers/base/core.c
> +++ b/drivers/base/core.c
> @@ -46,6 +46,8 @@ static bool fw_devlink_drv_reg_done;
>  static bool fw_devlink_best_effort;
>  static struct workqueue_struct *device_link_wq;
>
> +#define get_dev_from_fwnode(fwnode)    get_device((fwnode)->dev)

I think it is better to not have this wrapper. We want it to be clear
when we're acquiring a ref. I know get_device() does that, but I have
to look up what get_dev_from_fwnode() does exactly.

Side note: I didn't know fwnode has a ptr to the struct device. I
wonder if we can kill off of_find_device_by_node() using that. That's
for platform devices though.

Rob