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Date:   Thu, 13 Apr 2023 10:11:24 +0300
From:   Tony Lindgren <tony@atomide.com>
To:     Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= <u.kleine-koenig@pengutronix.de>
Cc:     Vignesh R <vigneshr@ti.com>,
        "Rafael J. Wysocki" <rafael@kernel.org>, linux-pm@vger.kernel.org,
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        Wolfram Sang <wsa@kernel.org>,
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        linux-i2c@vger.kernel.org, kernel@pengutronix.de,
        Aaro Koskinen <aaro.koskinen@iki.fi>,
        linux-omap@vger.kernel.org
Subject: Re: [PATCH] i2c: omap: Improve error reporting for problems during
 .remove()
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* Uwe Kleine-König <u.kleine-koenig@pengutronix.de> [230413 07:07]:
> On Thu, Apr 13, 2023 at 09:39:15AM +0300, Tony Lindgren wrote:
> > Oh OK. Care to clarify a bit why we are not allowed to return errors
> > on remove though? Are we getting rid of the return value for remove?
> > Sorry if I'm not following the cunning plan here :)
> 
> Yes, that's the plan. If you look at the caller of the remove functions
> (before 5c5a7680e67ba6fbbb5f4d79fa41485450c1985c):
> 
> static void platform_remove(struct device *_dev)
> {
>         struct platform_driver *drv = to_platform_driver(_dev->driver);
>         struct platform_device *dev = to_platform_device(_dev);
> 
>         if (drv->remove) {
>                 int ret = drv->remove(dev);
> 
>                 if (ret)
>                         dev_warn(_dev, "remove callback returned a non-zero value. This will be ignored.\n");
>         }
>         dev_pm_domain_detach(_dev, true);
> }
> 
> you see it's pointless to return an error value. But the prototype
> seduces driver authors to do it yielding to error that can easily
> prevented if .remove returns void. See also
> 5c5a7680e67ba6fbbb5f4d79fa41485450c1985c for some background and details
> of the quest.

OK thanks. So maybe check the pm_runtime_get_sync() and on error do
pm_runtime_put_noidle(), or pm_runtime_resume_and_get(). Both ways
are fine for me, maybe you already figured it out.

Regards,

Tony