Re: [REGRESSION] "bind" a device to a driver doesn't not work anymore

From: Greg KH <gregkh@suse.de>
To: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: ?ric Piel <eric.piel@tremplin-utc.net>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	linux-input@vger.kernel.org
Subject: Re: [REGRESSION] "bind" a device to a driver doesn't not work anymore
Date: Mon, 26 Oct 2009 13:59:53 -0700	[thread overview]
Message-ID: <20091026205953.GB11665@suse.de> (raw)
In-Reply-To: <20091023020150.GA26723@core.coreip.homeip.net>

On Thu, Oct 22, 2009 at 07:01:50PM -0700, Dmitry Torokhov wrote:
> On Sun, Oct 18, 2009 at 01:02:38AM -0700, Greg KH wrote:
> > On Sun, Oct 18, 2009 at 12:51:27AM -0700, Dmitry Torokhov wrote:
> > > On Mon, Oct 12, 2009 at 08:17:41PM -0700, Dmitry Torokhov wrote:
> > > > On Mon, Oct 12, 2009 at 11:54:17AM -0700, Greg KH wrote:
> > > > > On Mon, Oct 12, 2009 at 11:33:13AM -0700, Dmitry Torokhov wrote:
> > > > > > On Mon, Oct 12, 2009 at 10:35:51AM -0700, Greg KH wrote:
> > > > > > > On Mon, Oct 12, 2009 at 08:48:46AM -0700, Dmitry Torokhov wrote:
> > > > > > > > > So at least, unbind should fail as well as bind.
> > > > > > > > >
> > > > > > > > 
> > > > > > > > That would be Greg's domain s it is driver core decision whether to
> > > > > > > > allow unbinding platform devices registered with
> > > > > > > > platform_driver_probe().
> > > > > > > 
> > > > > > > No, I do not see why that should not be allowed.
> > > > > > > 
> > > > > > 
> > > > > > Because once you did unbind the device you are stuck (unless the driver
> > > > > > is compiled as a module, but then you could just unload the module
> > > > > > instead of unbinding). Disallowing unbind would allow discarding not
> > > > > > only __devinit but __devexit sections when driver is built in which
> > > > > > would make ebedded people happy[^Hier].
> > > > > 
> > > > > Yeah, good point.
> > > > > 
> > > > > Does anyone do bind/unbind with platform devices today?
> > > > > 
> > > > > If not, a patch changing this would be welcome.
> > > > > 
> > > > 
> > > > How about this one?
> > > > 
> > > 
> > > *ping* We need to resolve this, otherwise everyone who likes to rebind
> > > i8042 in couse of STR/STD will be in trouble.
> > 
> > Sorry, am in Tokyo right now.
> > 
> > I like this patch, and will queue it up, but it's too late for .32, it
> > will have to wait for .33.
> > 
> 
> Greg,
> 
> I hope you will reconsider. The patch is extremely small but without it
> I am afraid many people whose distributions blindly rebind i8042 on
> suspend/resume will lose their keyboards and mice now that i8042 uses
> platform_driver_probe()...

What distros do something like that automatically?  And this patch will
not solve that problem, just forbid it from happening, right?

thanks,

greg k-h