]> 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>
Wed, 4 Jun 2025 12:38:02 +0000 (14:38 +0200)
commit8de1d394e31ef686412656ac65493377e42b6b66
tree32e8a09f3ba348b3d4f132d316c51e52709e5ad9
parentb45a50fc1f4eb9992a01da14772b3159ec785f60
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