[PATCH 3/7] ARM: shmobile: sh73a0 dtsi: Add missing "gpio-ranges" to gpio node
Laurent Pinchart
laurent.pinchart at ideasonboard.com
Tue Jun 30 02:48:37 PDT 2015
Hi Geert,
Thank you for the patch.
On Tuesday 30 June 2015 09:45:23 Geert Uytterhoeven wrote:
> If a GPIO driver uses gpiochip_add_pin_range() (which is usually the
> case for GPIO/PFC combos), the GPIO hogging mechanism configured from DT
> doesn't work:
>
> requesting hog GPIO led1-high (chip sh73a0_pfc, offset 20) failed
>
> The actual error code is -517 == -EPROBE_DEFER.
>
> The problem is that PFC+GPIO registration is handled in multiple steps:
> 1. pinctrl_register(),
> 2. gpiochip_add(),
> 3. gpiochip_add_pin_range().
>
> Configuration of the hogs is handled in gpiochip_add():
>
> gpiochip_add
> of_gpiochip_add
> of_gpiochip_scan_hogs
> gpiod_hog
> gpiochip_request_own_desc
> __gpiod_request
> chip->request
> pinctrl_request_gpio
> pinctrl_get_device_gpio_range
>
> However, at this point the GPIO controller hasn't been added to
> pinctrldev_list yet, so the range can't be found, and the operation fails
> with -EPROBE_DEFER.
>
> To fix this, add a "gpio-ranges" property to the gpio device node, so
> the ranges are added by of_gpiochip_add_pin_range(), which is called by
> of_gpiochip_add() before the call to of_gpiochip_scan_hogs().
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas at glider.be>
This looks sane to me, even though referencing the same DT node seems a bit
dodgy. I'll let Linus comment on that, but for the implementation itself,
Acked-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> ---
> arch/arm/boot/dts/sh73a0.dtsi | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/arch/arm/boot/dts/sh73a0.dtsi b/arch/arm/boot/dts/sh73a0.dtsi
> index 11e17c5f26e2cae2..ff7c8f298f30a58d 100644
> --- a/arch/arm/boot/dts/sh73a0.dtsi
> +++ b/arch/arm/boot/dts/sh73a0.dtsi
> @@ -392,6 +392,9 @@
> <0xe605801c 0x1c>;
> gpio-controller;
> #gpio-cells = <2>;
> + gpio-ranges =
> + <&pfc 0 0 119>, <&pfc 128 128 37>, <&pfc 192 192 91>,
> + <&pfc 288 288 22>;
> interrupts-extended =
> <&irqpin0 0 0>, <&irqpin0 1 0>, <&irqpin0 2 0>, <&irqpin0 3 0>,
> <&irqpin0 4 0>, <&irqpin0 5 0>, <&irqpin0 6 0>, <&irqpin0 7 0>,
--
Regards,
Laurent Pinchart
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