Re: [PATCH 00/34] watchdog: Convert to platform remove callback returning void - Uwe Kleine-König

From: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
To: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
	Wim Van Sebroeck <wim@linux-watchdog.org>,
	Guenter Roeck <linux@roeck-us.net>,
	Doug Anderson <dianders@chromium.org>,
	Nicolas Ferre <nicolas.ferre@microchip.com>,
	Alexandre Belloni <alexandre.belloni@bootlin.com>,
	Claudiu Beznea <claudiu.beznea@microchip.com>,
	Florian Fainelli <f.fainelli@gmail.com>,
	Ray Jui <rjui@broadcom.com>,
	Scott Branden <sbranden@broadcom.com>,
	Vladimir Zapolskiy <vz@mleia.com>,
	Patrice Chotard <patrice.chotard@foss.st.com>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: kernel@pengutronix.de, linux-samsung-soc@vger.kernel.org,
	linux-watchdog@vger.kernel.org, patches@opensource.cirrus.com,
	Broadcom internal kernel review list 
	<bcm-kernel-feedback-list@broadcom.com>,
	linux-rpi-kernel@lists.infradead.org,
	Alim Akhtar <alim.akhtar@samsung.com>,
	linux-stm32@st-md-mailman.stormreply.com,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 00/34] watchdog: Convert to platform remove callback returning void
Date: Mon, 6 Mar 2023 18:05:34 +0100	[thread overview]
Message-ID: <20230306170534.vap4z24rbexbjj76@pengutronix.de> (raw)
In-Reply-To: <20230303213716.2123717-1-u.kleine-koenig@pengutronix.de>

[-- Attachment #1: Type: text/plain, Size: 2040 bytes --]

Hello,

[dropping Leela Krishna Amudala from the list of recipents as their
email address bounces]

On Fri, Mar 03, 2023 at 10:36:42PM +0100, Uwe Kleine-König wrote:
> this patch series adapts the platform drivers below drivers/watchdog to
> use the .remove_new() callback. Compared to the traditional .remove()
> callback .remove_new() returns no value. This is a good thing because
> the driver core doesn't (and cannot) cope for errors during remove. The
> only effect of a non-zero return value in .remove() is that the driver
> core emits a warning. The device is removed anyhow and an early return
> from .remove() usually yields a resource leak. One driver suffering from
> this problem (s3c2410) is fixed by the first patch.
> 
> By changing the remove callback to return void driver authors cannot
> reasonably (but wrongly) assume any more that there happens some kind of
> cleanup later.
> 
> All watchdog drivers but the above mentioned one returned zero
> unconditionally in their remove callback, so they could all be converted
> trivially to .remove_new().
> 
> Note that this series depends on commit 5c5a7680e67b ("platform: Provide
> a remove callback that returns no value") that is already in Linus' tree
> but not yet included in a tagged version.

This is fixed now, v6.3-rc1 is suitable as a base for this series.

Guenter pointed out that for some drivers it is possible to make use of
devm_watchdog_register_device() and drop the remove callback completely.
Also there is an alternative series that gets rid of s3c2410's remove
callback.

I'll send out a series converting the three drivers to
devm_watchdog_register_device() as Guenter suggested. To apply the
remainder of this series you might want to do:

	b4 am -l -P 2-7,9-25,27,29-33 20230303213716.2123717-1-u.kleine-koenig@pengutronix.de

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | https://www.pengutronix.de/ |

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]