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This logic fails on certain SoC controllers where open-drain lines in a high-impedance state are physically reported as inputs. This leads to a "deadlock" where the I2C core refuses to assign the recovery hooks because it incorrectly assumes the pins are input-only, even though they are fully capable of driving the bus low for recovery. Update the recovery initialization to use the new gpiod_is_single_ended() helper. If a GPIO is configured as open-drain or open-source in the firmware, it is safe to assume it can be used for bus recovery, even if the current hardware direction is reported as input. Signed-off-by: Jie Li Reviewed-by: Linus Walleij --- drivers/i2c/i2c-core-base.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index ae7e9c8b65a6..11bd801418e8 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -446,7 +446,8 @@ static int i2c_init_recovery(struct i2c_adapter *adap) if (bri->sda_gpiod) { bri->get_sda = get_sda_gpio_value; /* FIXME: add proper flag instead of '0' once available */ - if (gpiod_get_direction(bri->sda_gpiod) == 0) + if (gpiod_get_direction(bri->sda_gpiod) == 0 || + gpiod_is_single_ended(bri->sda_gpiod)) bri->set_sda = set_sda_gpio_value; } } else if (bri->recover_bus == i2c_generic_scl_recovery) { -- 2.43.0