Messages in this thread | | | Date | Fri, 26 Nov 2021 01:01:44 +0900 | From | "Hector Martin \"marcan\"" <> | Subject | Re: [PATCH v3 3/4] arm64: dts: apple: t8103: Add i2c nodes |
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On 2021年11月26日 0:50:28 JST, Linus Walleij <linus.walleij@linaro.org> wrote: >On Wed, Nov 24, 2021 at 6:42 AM Hector Martin <marcan@marcan.st> wrote: > >> Pulling down an I2C bus between transactions is not legal; the idle >> state has to be high. > >Oh right. > >> Apple are actually not very good at configuring GPIOs for power saving; >> e.g. the I/Os for that unused i2c bus still have their input buffers >> turned on, which is a waste of power. If they wanted to save the >> smallest drop of power they'd turn that off. But the effect of this is >> so trivial it probably makes no difference in the context of a laptop, >> nevermind a desktop like the Mac Mini. > >Hm that's true. The saying is that 99% is the backlight, the remaining 1% isn't >so significant after that.
From watching a USB power meter plugged into the MacBook Air, I can say the backlight is about 70% :-)
Then again, the new MBPs have LED matrix backlit screens... so suddenly dark themes are more efficient again! I should measure that one, see how much power changing themes saves.
-- Hector Martin "marcan" (marcan@marcan.st) Public key: https://mrcn.st/pub
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