[PATCH v4 2/3] pinctrl: exynos: Fix GPIO setup failure because domain clock being gated

Linus Walleij linus.walleij at linaro.org
Mon Jan 5 06:05:46 PST 2015

On Fri, Dec 5, 2014 at 12:00 PM, Krzysztof Kozlowski
<k.kozlowski at samsung.com> 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 at samsung.com>
> Tested-by: Javier Martinez Canillas <javier.martinez at collabora.co.uk>

Tomasz, is this OK and should I apply it for fixes or next?

Linus Walleij

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