From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marek Szyprowski <m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
Subject: Re: [PATCH 04/29] drivers: base: add notifier for failed driver bind
Date: Tue, 26 Aug 2014 08:30:04 +0200
Message-ID: <53FC296C.1030202@samsung.com>
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To: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
Cc: Thierry Reding <treding-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>, linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Shaik Ameer Basha <shaik.ameer-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>, Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Inki Dae <inki.dae-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, Greg Kroah-Hartman <gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>, "Rafael J. Wysocki" <rjw-LthD3rsA81gm4RdzfppkhA@public.gmane.org>, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Tomasz Figa <tomasz.figa-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, linaro-mm-sig-cunTk1MwBs8s++Sfvej+rw@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Kukjin Kim <kgene.kim-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, Laurent Pinchart <laurent.pinchart-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org>, Sylwester Nawrocki <s.nawrocki-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, Kyungmin Park <kyungmin.park-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, Cho KyongHo <pullip.cho-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
List-Id: iommu@lists.linux-foundation.org

Hello,

On 2014-08-25 23:18, Joerg Roedel wrote:
> On Tue, Aug 05, 2014 at 12:47:32PM +0200, Marek Szyprowski wrote:
>> +	if (failed && dev->bus)
>> +		blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
>> +					     BUS_NOTIFY_DRVBIND_FAILED, dev);
>> +
> Why can't you just use the notifier for BUS_NOTIFY_UNBIND_DRIVER or
> BUS_NOTIFY_UNBOUND_DRIVER when something goes wrong in driver
> initialization?

Hmmm, you might be right. BUS_NOTIFY_UNBIND_DRIVER event happens before 
unbinding
the driver, but BUS_NOTIFY_UNBOUND_DRIVER is called when driver remove 
has been
finished, so it can be considered as a symmetrical pair for 
BUS_NOTIFY_BIND_DRIVER.
Driver which registered bus notifiers is mainly interested in doing 
right cleanup,
so the code executed for IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER and
IOMMU_GROUP_NOTIFY_DRVBIND_FAILED is same.

I will remove this additional event and simply add a call to
BUS_NOTIFY_UNBOUND_DRIVER event when driver probe fails.

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland