[PATCH] pinctrl: bcm2835: reduce GPPUD set-up time

Linus Walleij linus.walleij at linaro.org
Fri Nov 4 08:29:22 PDT 2016

On Mon, Oct 31, 2016 at 2:21 PM, Stefan Wahren <stefan.wahren at i2se.com> wrote:

> Since the BCM2835 datasheet doesn't exactly specify the set-up time for
> the GPIO Pull-up/down Clock Registers there was an assumption of 150 cycles
> at a clock rate of 1 MHz. During a discussion [1] in the Raspberry Pi forum
> it turns out that clock rate refers to the VPU which has a rate of 250 MHz.
> So we can reduce the delay to a sensible value and update the comment above.
> I tested this optimization with a Raspberry Pi B and a multimeter.
> [1] - https://www.raspberrypi.org/forums/viewtopic.php?f=72&t=163352
> Signed-off-by: Stefan Wahren <stefan.wahren at i2se.com>

Patch applied with Eric's review tag.

Linus Walleij

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