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    SubjectRe: [PATCH RFC] modpost: Support I2C Aliases from OF tables
    Hi Javier,

    On Tue, Aug 6, 2019 at 12:25 AM Javier Martinez Canillas
    <javierm@redhat.com> wrote:
    > On 7/31/19 9:44 PM, Wolfram Sang wrote:
    > > Hi Javier,
    > >> The other option is to remove i2c_of_match_device() and don't make OF match
    > >> to fallback to i2c_of_match_device_sysfs(). This is what happens in the ACPI
    > >> case, since i2c_device_match() just calls acpi_driver_match_device() directly
    > >> and doesn't have a wrapper function that fallbacks to sysfs matching.
    > >>
    > >> In this case an I2C device ID table would be required if the devices have to
    > >> be instantiated through sysfs. That way the I2C table would be used both for
    > >> auto-loading and also to match the device when it doesn't have an of_node.
    > >
    > > That would probably mean that only a minority of drivers will not add an I2C
    > > device ID table because it is easy to add an you get the sysfs feature?
    > >
    >
    > I believe so yes.

    > As Masahiro-san mentioned, this approach will still require to add a new macro
    > MODULE_DEVICE_TABLE(i2c_of, bar_of_match) so the OF device table is used twice.
    >
    > One to expose the "of:N*T*Cfoo,bar" and another one to expose it as "i2c:bar".
    >
    > I expect that many developers would miss adding this macro for new drivers that
    > are DT-only and so sysfs instantiation would not work there. So whatever is the
    > approach taken we should clearly document all this so drivers authors are aware.

    You could add a new I2C_MODULE_DEVICE_TABLE() that adds both, right?
    Makes it a little bit easier to check/enforce this.

    Gr{oetje,eeting}s,

    Geert

    --
    Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

    In personal conversations with technical people, I call myself a hacker. But
    when I'm talking to journalists I just say "programmer" or something like that.
    -- Linus Torvalds

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