Re: [PATCH v2 3/5] pinctrl: exynos: Fix GPIO setup failure because domain clock being gated

From: Linus Walleij
Date: Fri Nov 28 2014 - 09:04:55 EST


On Wed, Nov 26, 2014 at 3:24 PM, Krzysztof Kozlowski
<k.kozlowski@xxxxxxxxxxx> wrote:

> The audio subsystem on Exynos 5420 has separate clocks and GPIO. To
> operate properly on GPIOs the main block clock 'mau_epll' must be
> enabled.
>
> This was observed on Peach Pi/Pit and Arndale Octa (after enabling i2s0)
> after introducing runtime PM to pl330 DMA driver. After that commit the
> 'mau_epll' was gated, because the "amba" clock was disabled and there
> were no more users of mau_epll.
>
> The system hang just before probing i2s0 because
> samsung_pinmux_setup() tried to access memory from audss block which was
> gated.
>
> Add a clock property to the pinctrl driver and enable the clock during
> GPIO setup. During normal GPIO operations (set, get, set_direction) the
> clock is not enabled.
>
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>

Waiting for Tomasz to review this.

Can this patch be applied in separation from the others?

Yours,
Linus Walleij
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