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Commitd1d564ec49("gpio: move hogs into GPIO core") made gpiochip_add_hog() return -EINVAL for hog nodes lacking any of the 'input', 'output-low' or 'output-high' properties. The error is propagated by gpiochip_hog_lines() and fails registration of the whole GPIO chip. The previous OF-specific implementation tolerated such nodes: of_parse_own_gpio() warned "no hogging state specified, bailing out" and of_gpiochip_add_hog() stopped processing the node without failing chip registration. Some boards deliberately ship hog nodes without a hogging state in their base devicetree and supply the state via overlay, e.g. the PCIe slot key selection hogs on the BananaPi R4 Pro added in commite309fa232d("arm64: dts: mediatek: mt7988a-bpi-r4pro: rework pcie gpio-hog handling"), as the polarity set in the base devicetree could not be overridden from an overlay. Booting such a board without an overlay applied now fails to register the gpiochip. On the BananaPi R4 Pro this means the MT7988A pinctrl device fails to probe, all peripherals including the console UART defer forever, and the board finally hangs when clk_disable_unused() gates the clocks of the UART still in use by earlycon: gpiochip_add_data_with_key: GPIOs 512..595 (pinctrl_moore) failed to register, -22 mt7988-pinctrl 1001f000.pinctrl: error -EINVAL: Failed to add gpio_chip ... clk: Disabling unused clocks (hangs) Restore the previous behaviour by warning about hog nodes lacking a hogging state and skipping them instead of failing the registration of the whole GPIO chip. Fixes:d1d564ec49("gpio: move hogs into GPIO core") Cc: stable@vger.kernel.org Signed-off-by: Daniel Golle <daniel@makrotopia.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://patch.msgid.link/4c67cf0839ccf57db35a826df6d8fc779531509a.1783974733.git.daniel@makrotopia.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
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