• Brian Masney's avatar
    gpiolib: ensure that fwnode is properly set · 24c94060
    Brian Masney authored
    Note that this is a RFC patch and not meant to be merged. I looked into
    a problem with linux-next-20221110 on the Qualcomm SA8540P automotive
    board (sc8280xp) where the UFS host controller would fail to probe due
    to repeated probe deferrals when trying to get reset-gpios via
    devm_gpiod_get_optional().
    
    of_get_named_gpiod_flags() returns -EPROBE_DEFER, which is caused by
    of_gpiochip_match_node_and_xlate() returning 0 since the of_xlate function
    pointer is not set for the qcom,sc8280xp-tlmm pinctrl driver. The
    pinctrl driver doesn't define one, so of_gpiochip_add() should
    automatically setup of_gpio_simple_xlate() on it's behalf. This doesn't
    happen since the fwnode member on the struct gpiochip is set to null
    when of_gpiochip_add() is called. Let's work around this by ensuring
    that it's set if available.
    
    Note that this broke sometime within the last few weeks within
    linux-next and I haven't bisected this. I'm posting this in the hopes
    that someone may know offhand which patch(es) may have broken this.
    Signed-off-by: default avatarBrian Masney <bmasney@redhat.com>
    Tested-by: default avatarMarijn Suijten <marijn.suijten@somainline.org>
    Tested-by: default avatarKonrad Dybcio <konrad.dybcio@linaro.org>
    Tested-by: Steev Klimaszewski <steev@kali.org> #Lenovo Thinkpad X13s
    Tested-by: default avatarNeil Armstrong <neil.armstrong@linaro.org>
    Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@linaro.org>
    24c94060
gpiolib.c 123 KB