Re: [RFC PATCH 4/5] ACPI video: support reversed _BCL method

[Matthew Garrett <mjg59@srcf.ucam.org>]

On Wed, Mar 11, 2009 at 09:42:55AM +0800, Zhang Rui wrote:

> The index value returned by _BQC is the index in the PCTG package.
> if the _BCL package is in a reversed order, we can not use this index to
> get the value in device->brightness->levels[].
> For example, if the current brightness is 0x64, _BQC returns 0 in this
> case, but we can not translate this to value 0x14, we need a flag to
> tell us that _BCL is reversed.
> 
> But in the non-indexed case, _BQC always returns a percentage that can
> be used directly by ACPI video driver, i.e. we don't need to parse
> device->brightness->levels to get the real value. so we don't need to
> check the device->brightness->flags._BCL_reversed bit.

Ah, of course. Sorry, I should have got that. Thanks for the 
explanation!

Acked-by: Matthew Garrett <mjg@redhat.com>

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