PIN_CTRL_BL
hd->pins[PIN_CTRL_BL] = devm_gpiod_get_optional(dev, "backlight",
if (IS_ERR(hd->pins[PIN_CTRL_BL])) {
ret = PTR_ERR(hd->pins[PIN_CTRL_BL]);
if (hd->pins[PIN_CTRL_BL])
gpiod_set_value_cansleep(hd->pins[PIN_CTRL_BL], on);