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Date: Tue, 14 Jul 2009 02:53:26 +0100
From: Matthew Garrett <mjg59@srcf.ucam.org>
To: ykzhao <yakui.zhao@intel.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
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Subject: Re: [PATCH 1/3] backlight: Allow drivers to update the core, and
	generate events on changes
Message-ID: <20090714015326.GA9044@srcf.ucam.org>
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On Tue, Jul 14, 2009 at 08:58:48AM +0800, ykzhao wrote:

> It will be better to send the event to user space only when the
> brightness is updated successfully.

That guarantees that we have to read back the brightness, which may be 
expensive on some hardware.

> It seems that the acpi video driver will send the ACPI event to user
> space when updating the brightness. 
> Is it necessary to send the udev-event again?

Yes. There's no reason to special-case the ACPI driver.

-- 
Matthew Garrett | mjg59@srcf.ucam.org
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