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    SubjectRE: [PATCH v2] gpio: mmio: handle "ngpios" properly in bgpio_init()
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    > > bgpio_init() uses "sz" argument to populate ngpio, which is not
    > > accurate. Instead, read the "ngpios" property from the DT and if it
    > > doesn't exist, use the "sz" argument. With this change, drivers no
    > > longer need to overwrite the ngpio variable after calling bgpio_init.
    >
    > ...
    >
    > > + ret = device_property_present(dev, "ngpios");
    > > + if (!ret)
    >
    > ret is not of the correct type for this call.
    >
    > Why not simply
    >
    > if (!device_property_present(dev, "ngpios"))
    >
    > > + gc->ngpio = gc->bgpio_bits;
    >
    > ...
    >
    > The problem with this change is that you need to provide bgpio_bits.
    >
    > So, if there is a property when bgpio_bits will be updated?
    >
    > That's said what you need is something like this:
    > 1) split "ngpios" handling code (lines ~718-744 in gpiolib.c) into a helper
    > function that is available inside drivers/gpio;
    > 2) use it in bgpio_init() by overriding bgpio_bits.
    >
    > ret = new_helper();
    > if (ret)
    > gc->bgpio_bits = sz * 8;
    > else
    > ... = gc->ngpio;

    So this new_helper() which reads the ngpios property, would be called from bgpio_init() and
    From gpiochip_add_data_with_key() correct? Since there are some drivers that don’t use
    bgpio_init().
    Also, shouldn't "gc->bgpio_bits = = sz * 8;" be independent of new_helper() function?
    "bgpio_bits" is described as "number of register bits used for a generic GPIO i.e. <register width> * 8"
    which seems different from "ngpio" described as "the number of GPIOs handled by this controller"



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