]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
pinctrl: devicetree: do not goto err when probing hogs in pinctrl_dt_to_map
authorValentin Caron <valentin.caron@foss.st.com>
Thu, 16 Jan 2025 17:00:09 +0000 (18:00 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 29 May 2025 09:13:20 +0000 (11:13 +0200)
commit250be316fb4c01cbcabd9aa265405705c6dd17b2
tree3bec06de4a08b0239249a535c0edf48232b68631
parent2fc4b956badf57d84c0a955dfc048fe672d1b5e2
pinctrl: devicetree: do not goto err when probing hogs in pinctrl_dt_to_map

[ Upstream commit c98868e816209e568c9d72023ba0bc1e4d96e611 ]

Cross case in pinctrl framework make impossible to an hogged pin and
another, not hogged, used within the same device-tree node. For example
with this simplified device-tree :

  &pinctrl {
    pinctrl_pin_1: pinctrl-pin-1 {
      pins = "dummy-pinctrl-pin";
    };
  };

  &rtc {
    pinctrl-names = "default"
    pinctrl-0 = <&pinctrl_pin_1 &rtc_pin_1>

    rtc_pin_1: rtc-pin-1 {
      pins = "dummy-rtc-pin";
    };
  };

"pinctrl_pin_1" configuration is never set. This produces this path in
the code:

  really_probe()
    pinctrl_bind_pins()
    | devm_pinctrl_get()
    |   pinctrl_get()
    |     create_pinctrl()
    |       pinctrl_dt_to_map()
    |         // Hog pin create an abort for all pins of the node
    |         ret = dt_to_map_one_config()
    |         | /* Do not defer probing of hogs (circular loop) */
    |         | if (np_pctldev == p->dev->of_node)
    |         |   return -ENODEV;
    |         if (ret)
    |           goto err
    |
    call_driver_probe()
      stm32_rtc_probe()
        pinctrl_enable()
          pinctrl_claim_hogs()
            create_pinctrl()
              for_each_maps(maps_node, i, map)
                // Not hog pin is skipped
                if (pctldev && strcmp(dev_name(pctldev->dev),
                                      map->ctrl_dev_name))
                  continue;

At the first call of create_pinctrl() the hogged pin produces an abort to
avoid a defer of hogged pins. All other pin configurations are trashed.

At the second call, create_pinctrl is now called with pctldev parameter to
get hogs, but in this context only hogs are set. And other pins are
skipped.

To handle this, do not produce an abort in the first call of
create_pinctrl(). Classic pin configuration will be set in
pinctrl_bind_pins() context. And the hogged pin configuration will be set
in pinctrl_claim_hogs() context.

Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/20250116170009.2075544-1-valentin.caron@foss.st.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/pinctrl/devicetree.c