lkml.org 
[lkml]   [2010]   [Dec]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 2/2] regulator: Optimise out noop voltage changes
On Thu, Dec 16, 2010 at 05:46:07PM -0800, Saravana Kannan wrote:
>
> 1. With support for multiple consumers, we can further optimize and call
> the producer's set voltage only if the final voltage range changes. So if
> consumer A asks for (2.0 - 5.0) and consumer B keeps changing between (1.0
> - 5.0) and (1.5 - 5.0), then we can completely no-op all of consumer B's
> calls.

Yes, that could be done as a further optimisation - we'd be able to bale
out after the

> 2. When I was trying to do the above this Sunday, I also noticed what
> looks like a bug or at least an unpleasant behavior. A consumer's min_uV
> and max_uV were being updated (for-next around Dec 12th) before calling
> the producer's set voltage. So, in the above example, if consumer C comes
> in and asks for (10 - 15), it will prevent the producer voltage from ever
> changing again. All of consumer A and B's future requests will result in a
> failure since min_uV > max_uV when you do the consumer aggregation.

I'm sorry I can't parse this at all. What is a producer?

If the consumers are all asking for incompatible things there's a system
integration issue and the consumers need to be sorted out; it's
difficult for the regulator API to do anything safely while everything
wants incompatible configurations.


\
 
 \ /
  Last update: 2010-12-17 12:47    [W:0.035 / U:0.576 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site