ARM: shmobile: r8a73a4 dtsi: Add missing "gpio-ranges" to gpio node
authorGeert Uytterhoeven <geert+renesas@glider.be>
Tue, 4 Aug 2015 13:55:14 +0000 (15:55 +0200)
committerSimon Horman <horms+renesas@verge.net.au>
Tue, 4 Aug 2015 21:39:27 +0000 (06:39 +0900)
commit17ccec50cc40bef00b26d506d483e928804cb20e
tree1f13e8eece94e1e84ce883d368f4dbf7cb012c19
parent054531e7a5cb195140bead068b51cc6147c5c8bf
ARM: shmobile: r8a73a4 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 r8a73a4_pfc, offset 28) 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>
arch/arm/boot/dts/r8a73a4.dtsi