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ARM: shmobile: sh73a0 dtsi: Add missing "gpio-ranges" to gpio node 

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@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
This commit is contained in:
Geert Uytterhoeven 2015-08-04 15:55:16 +02:00 committed by Simon Horman
parent 09d1c7b4ba
commit 94bdc48d55
1 changed files with 3 additions and 0 deletions
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3
arch/arm/boot/dts/sh73a0.dtsi
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@ -392,6 +392,9 @@ pfc: pfc@e6050000 {
<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>,